PHARMACOLOGICAL SCREENING AND ISOLATION OF BIOACTIVE 
COMPOUNDS FROM PLANTS USED AGAINST ELEPHANTIASIS IN 

THE EASTERN CAPE, 
SOUTH AFRICA   

By 

Zanele Adams 

2016203149 

 

A thesis submitted in fulfilment of the requirements for the degree  
Philosophiae Doctor in Botany in the Faculty of Natural and 

Agricultural Sciences, Department of Plant Sciences, University of 
the Free State Qwaqwa, South Africa.  

 

  
 

 
 

March 2023 
 
 
 
 

    Promoter (Internal): Dr P.J. Mojau 
 

                          Co-Promoter (Internal):  Prof L.V. Komoreng 
   

                   Co-Promoter (External) Prof M.M.O. Thekisoe 
  

 



i 
 

DECLARATION 
 
 
I, Zanele Adams, declare that the Master’s Degree research dissertation or 

interrelated, publishable manuscripts/published articles, or course work Master’s 

Degree mini-dissertation that I herewith submit for the PhD Degree qualification in 

Botany at the University of the Free State Qwaqwa Campus is my independent work, 

and that I have not previously submitted it for a qualification at another institution of 

higher education. 

 

 

I, Zanele Adams, hereby declare that I am aware that the copyright is vested in the 

University of the Free State. 

 

 

I, Zanele Adams, hereby declare that all royalties as regards intellectual property that 

was developed during the course of and/ or in connection with the study at the University 

of the Free State, will accrue to the University. 

 

 

 

 

 

 

                                                                                

 

 

 
  

Zanele Adams 



ii 
 

ACKNOWLEDGEMENTS 
 

I wish to extend my sincere gratitude to God almighty for the precious gift of life and 

endowing me with the strength, faith to work through my project after granting me the 

opportunity to enrol for my Ph.D. My gratitude also goes to Prof Komoreng for believing 

in me and granting me the opportunity to work with her as a research student, to Dr 

Mojau for his supervision and mentoring through the study and to Prof Thekisoe my 

co-supervisor for all the support he showed.  

 

To all the traditional healers and herbalists from the OR Tambo District Municipality, 

Eastern Cape who took part in the ethnobotanical survey, thank you for the help you 

provided in collection of plant material and knowledge shared during the survey. 

 

I also wish to extend my gratitude to Dr. Suranie Horn and Prof. Rialet Pieters from 

the North-West University for letting us use their lab and helping with the cytotoxicity 

experiments. We appreciate Prof. Nomngongo and her research group's assistance 

with the nuclear magnetic resonance (NMR) spectroscopy from the University of 

Johannesburg. 

 

My acknowledgments also go to my dear family and my dear friends Olwethu Kutta 

and Thandeka Dabata for the love, encouragement and support they showed me. For 

their emotional support and help with lab supplies, I would also want to thank the 

personnel at the University of the Free-Botany State's Department at the QwaQwa 

campus, particularly Prof. Ashafa, Dr. Sandy Steenhuisen, Dr. Rudo Ngara, and Mr. 

Mzizi Ngaka. My beloved colleagues Mrs. Laetitia Voua Otomo, Mr. Victor Mandla 

Hlongwane, Miss. Thumeka Tiwani, Miss. Sellwane Moloi, Miss. Gloria Lehasa, and 

Miss. Grace Mochologi deserve a heartfelt thank you for being the best colleagues for 

the love and support they showed me during this study. I am also very grateful and 

thankful for the financial support received from the National Research Foundation 

(NRF) and the UFS tuition fee bursary.  

 
 
 



iii 
 

DEDICATION 
 

This dissertation is in honor of my beloved parents. Julian Thembekile Adams and 

Freedom Nkululeko Adams; my dear brothers and sisters, Vuyiswa, Vuyelwa, 

Siphelele and the late Phakamile Adams; my beloved nieces and nephews; my 

beloved daughter Unathi Oratilwe Adams and my late cousin Velile Adams who once 

said I should be a doctor one day.  

 
 

  



iv 
 

ABSTRACT 
 

Elephantiasis, also known as lymphatic filariasis, is a medical condition brought on by 

parasitic worms that invade the lymphatic system causing obstructions of lymph fluid 

in the passaged that is associated with excessive swelling of the lower and upper limbs 

resulting in disability, swelling of genitalia and breasts. The condition is also associated 

with non-filarial causes including certain sexually transmitted diseases, tuberculosis, 

leishmaniasis, leprosy and podoconsiasis. The World Health Organization lists the 

illness as one of the neglected tropical diseases that primarily affects developing 

nations. Although no precise figures have been provided, South Africa is one of the 

African nations where incidences of the illness have been reported. 

 

Plants are reported in treating several medical conditions that affect human kind. 

Traditional medicine has been considered as an alternative to Western medicine as it 

is easily accessible and the latter being more expansive. The continued use of plant 

medicine creates the need to identify those substances that are responsible for the 

biological activity or the healing properties found in plant extracts through scientific 

validation. Plants are used by indigenous people and traditional healers in different 

areas to treat the similar or different conditions. South Africa has a wide variety of 

plants, and traditional plant studies is reported in literature. 

 

In three municipalities of the OR Tambo District Municipality in the Eastern Cape of 

South Africa, an ethnobotanical survey on medicinal plants used in the management 

and treatment of lymphatic filariasis was carried out. A total of 29 therapeutic plants 

from 25 different Angiosperm families were recorded. Acokanthera oblongifolia 

Curtisia dentata, Dioscorea sylvatica, Elephantorrhiza elephantina, Gunnera 

perpensa, Hypoxis hemerocallidea, Pentanisia prunellloides and R. melanophloeos 

were reported as the most used plants in the study to treat elephantiasis and various 

ailments. The roots followed by the leaves and stem bark were the most used plant 

parts with infusions and decoctions being reported as the most frequently methods of 

administration.  

 
 



v 
 

In vitro studies such as antimicrobial activity, antioxidant activity, phytochemical 

analysis, anti-inflammatory activity and cytotoxicity activity on mammalian cells were 

investigated. Bioactive compounds were also isolated and identified from K. 

drepanophylla. 

 

Antimicrobial screening from the ethnobotanical survey took into consideration the 

plants which were the most cited in the study and ones which were not studied before 

for the treatment of lymphatic filariasis.   Eight different plant species were evaluated 

in relation to aqueous and organic extracts (32) for antimicrobial properties using the 

micro -titre plate dilution plate method. Gram-positive bacteria Staphylococcus aureus, 

Staphylococcus epidermidis and Enterococcus faecalis as well as Gram-negative 

bacteria Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Shigella 

flexneri and Proteus vulgaris were tested for minimum inhibitory concentration (MIC) 

and minimum bactericidal concentration (MBC).  A. oblongifolia, C. dentata, D. 

sylvatica, G. perpensa, K. drepanophylla, and R. melanophloeos were among the 

plants whose acetone and ethanol extracts had good MIC and MBC activity against 

both Gram-positive and Gram-negative bacteria with MIC values ranging from 0.098 

to 0.78 mg/ml. C. dentata acetone and ethanol extracts dispalyed poor MBC activity 

against P. vulgaris, S. flexneri, K. pneumoniae, and E. faecalis. G. perpensa water 

extract demonstrated higher MBC efficacy to the ethanol extract against P. vulgaris, 

S. flexneri, K. pneumoniae, and E. faecalis at 6.25 mg/ml and 12.5 mg/ml respectively. 

At 0.098/ml, 0.098/ml, and 0.39/ml, respectively, the aqueous extracts of G. perpensa 

demonstrated good MICs and MBCs against E. coli, P. aeruginosa and P. vulgaris. At 

concentrations of 0.098/0.098 mg/ml, 0.195/3.125 mg/ml, and 0.78/0.78 mg/ml, 

respectively, K. drepanophylla water extracts demonstrated MICs and MBCs efficacy 

against the 3 strains. According to the findings, the effectiveness of the plant extracts 

against bacteria varied depending on the type of solvent employed. Different bacterial 

strains are susceptible to the effects of plant extracts and their essential oils in various 

ways, including by disrupting the phospholipid bilayer of the cell membrane, which 

makes it more permeable, causing the membrane to lose some of its cellular 

components, damaging certain cellular enzymes, and destroying or inactivating 

genetic material (Doughari, 2012).  
 
 



vi 
 

The microdilution assay was used to assess the plant extracts for antifungal activity 

against Candida albicans, Candida vulgaris, and Trichophyton mucoides. The acetone 

extracts of G. perpensa, K. drepanophylla and R. melanophloeos among the studied 

plant extracts demonstrated outstanding MIC and MFC (minimum fungicidal activity) 

against all three microorganisms between 0.098 and 0.78 mg/ml. While the MFC 

values against the three fungi strains were at 3.125 mg/ml, C. dentata ethanol extracts 

inhibited C. albicans, C. vulgaris, and T. mucoides at 0.195 mg/ml, 0.195 mg/ml, and 

0.78 mg/ml, respectively. Aqueous extracts of A. oblongifolia, C. dentata, G. perpensa 

and K. drepanophylla displayed favorable MIC and MFC activities. 

 

Concerning antimycobacterial activity, M. tuberculosis was used as the test strain. 

Among the plant species tested A. oblongifolia, C. dentata, H. albiflos and K. 

drepanopyhlla exhibited the best activity. The excellent MIC values for the acetone 

extracts ranged from 0.098 to 0.39 mg/ml. The ethanol extract's MIC ranged from 

0.098 to 0.78 mg/ml. Extracts of ethyl acetate exhibited efficacy ranging from 0.39 to 

0.78 mg/ml. H. albiflos demonstrated the best MIC and MFC activity for the water 

extracts at 0.098 and 0.195 mg/ml, respectively. 

 

Since phytochemical substances are known to be involved in biological processes 

such as antibacterial activity and other biological functions, their existence in certain 

plant species was examined using qualitative and quantitative techniques. All of the 

studied plant species tested positive for saponins, flavonoids, anthraquinones, and 

terpenoids, according to the findings of the qualitative analysis. A. oblongifolia is the 

only plant that tested positive for all phytochemicals including alkaloids, tannins, 

cardiac glycosides and steroids. Cardiac glycosides and steroids were the least 

present compounds. Quantitative analysis results showed that the tested 

phytochemicals existed in varying quantities. The most prevalent phytochemicals 

discovered in the plants were determined to be flavonoids and phenols. The largest 

concentrations of phenols were found in the acetone, ethanol, and aqueous extracts 

of G. perpensa and C. dendata, while the highest concentrations of flavonoids were 

found in the extracts of K. drepanophylla and G. perpensa. The acetone extract of R. 

melanophloeos (1.867 mg/g GAE g -1), the ethanolic extract (1.627 mg/g GAE g -1), 

and the water extract (1.045 mg/g GAE g -1) were found to contain the highest 



vii 
 

concentrations of tannins. The extracts of K. drepanophylla in acetone (0.364 mg/g 

QE g-1) and ethanol (0.249 mg/g QE g-1) contained the most flavonols.   

 

The antimicrobial qualities of the analysed plant extracts are thought to be caused by 

phytochemicals. 

 

The DPPH and ABTS tests were used to evaluate the antioxidant activity. The 

acetone, ethanol, and water extracts of K. drepanophylla, followed by the ethanol and 

water extracts of C. dentata, demonstrated the strongest antioxidant activity, according 

to the results of the DPPH experiment. K. drepanophylla and C. dentata demonstrated 

the best anti-DPPH activity and the best anti-ABTS activity, respectively, for the water 

extracts. R. melanophloeos acetone extract demonstrated the highest level of activity, 

with an IC50 value of 27.40 µg/ml ± 13.73. 

 

Concerning anti-inflammatory activity using 5- Lipoxygenase assay, C. dentata, K. 

drepanophylla and R. melanophloeos water extracts displayed higher anti-

inflammatory activity than that of NDGA and inhibited 5-LOX. C. dentata and K. 

drepanophylla water extracts displayed the best activity at (0.05 ± 0.02 and 0.05 ± 

1.10 μg/ml). For ethanol extract, K. drepanophylla and G. perpensa also exhibited 

good activity at 0.10 ± 0.11 μg/ml and 0.11 ± 0.07 respectively. The extracts inhibited 

5-LOX by showing higher anti-inflammatory activities than NDGA (0.29 ± 0.11 μg/ml).  

 

Cytotoxicity of plant extracts was tested using human duodenum cancer (Hutu-80) 

cells and rat hepatoma (H4IIE-luc) cells. C. dentata water extract displayed non-

toxicity when administered against Hutu-80 cells at the highest concentration and the 

H4IIE-luc cells managed to proliferate at the lowest concentration. Acetone extract of 

K. drepanophylla revealed that the cells proliferate at high concentrations and the 

water extract revealed that the plant is non-toxic after a period of 48 h when 

administered starting at 0.5 mg/ml to 0.03125 mg/ml. 

 

The goal of the study was to separate the active components from the highly active 

plant extract and then isolate, characterise, and identify the compound using 

spectroscopic methods, which revealed its structure. Following extraction, column 

chromatography, thin layer chromatography, and bioautography, isolation was carried 



viii 
 

out. An active substance that demonstrated antibacterial activity by preventing the 

growth of S. aureus was identified after the bioautography assay indicated it. Utilising 

1H-NMR, the isolate was characterised. The dimeric anthraquinone 10-hydroxy-10,7-

(chrysophanolanthrone)chrysophanol, which was isolated from the roots of K. 

isoetifolia, showed a proton structure in the spectrum that was 75% comparable to it. 

 

Keywords: elephantiasis, lymphatic filariasis, plant extracts, antimicrobial, 

phytochemical, antioxidant, anti-inflammatory and cytotoxicity. 

 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 



ix 
 

PAPERS PUBLISHED FROM THIS THESIS 
 
 

Adams, Z., Thekisoe, O., & Buwa‑Komoreng, L. (2021). An ethnobotanical survey of 

traditional medicinal plants used against elephantiasis in the OR Tambo district, 

Eastern Cape, South Africa. Pharmacognosy Magazine, 17, 915-22. 

 

 
CONFERENCE CONTRIBUTIONS  

 
Poster: Adams, Z., Thekisoe, O., & Buwa‑Komoreng, L. An ethnobotanical survey of 

traditional medicinal plants used against elephantiasis in the OR Tambo district, 

Eastern Cape, South Africa. 45th Annual SAAB Conference, University of 
Johannesburg, South Africa. 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 



x 
 

TABLE OF CONTENTS 
 

DECLARATION ……………..................................................................................... i 

ACKNOWLEDGEMENTS ….................................................................................... ii  

DEDICATION ……................................................................................................... iii  

ABSTRACT ……...................................................................................................... iv   

LIST OF TABLES .................................................................................................... xv  

LIST OF FIGURES ……………………………………………...………………………. xvi 

LIST OF ABBREVIATIONS .................................................................................... xxi 

 

 
CHAPTER 1 ……………………………………………………………………………….. 1 
LITERATURE REVIEW ………………………………………………………………….. 1 
1.1 Introduction ………………………………………………………………………… 1 

1.2 Aetiology of elephantiasis ………………………………………………………… 3  

1.2.1 Filarial elephantiasis …………………………………………………………3 

1.2.2 Wolbachia as a symbiont ……………………………………………………5  

1.2.3 Non-filarial elephantiasis …………………………………………………… 6 

1.3 Transmission of elephantiasis ……………………………………………………. 7 

1.4 Prevalence of elephantiasis ……………………………………………………… 8 

1.5 Management and treatment of elephantiasis (LF) …………………………….. 13 

1.6 Medicinal plants in the treatment of elephantiasis ………………….............. 13 

1.7 Use of medicinal plants in South Africa …………………………………….…. 14 

1.8 Major groups of plant secondary metabolites ………………………………… 15 

1.8.1 Phenolic compounds ……………………………………………………... 16 

1.8.2 Flavonoids …………………………………………………………………. 16 

1.8.3 Tannins ………………………………………………………………….…. 18  

1.8.4 Alkaloids ……………………………………………………………………. 19 

1.8.5 Saponins …………………………………………………………………… 20 

1.8.5 Terpenes …………………………………………………………………..  21 

1.9 Phytochemicals as antioxidants and their free radical scavenging ability …. 21 



xi 
 

1.10 Inflammation and diseases …………………………………………………. 23 

1.10.1 Oxidative species as inflammation mediators ………………………. 25 

           1.10.2 Lymphoedema and inflammation …………………………………….. 26 

1.10.3 Medicinal plants as alternatives for inflammatory diseases ….…..... 27  

1.10.4 Non-steroidal anti-inflammatory drugs (NSAIDs) ……………………. 28 

1.11 Problem Statement …………………………………………………………….. 29 

1.12 Aim and objectives …………………………………………………………….. 30  

1.12.1 Aim …………………………………………………………………….…. 30 

1.12.2 Objectives of the study …………………………………………………. 30 

References ………………………………………………………………………………. 31 

  

 

 
CHAPTER 2 ……………………………………………………………………………… 45 
AN ETHNOBOTANICL SURVEY TRADITIONAL MEDICINAL PLANTS USED 
AGAINST ELEPHANTIASIS IN THE OR TAMBO DISTRICT, EASTERN CAPE, 
SOUTH AFRICA ………………………………………………………………………… 45  
Abstract …………………………………………………………………………………… 47 

Introduction ………………………………………………………………………………. 47 

Materials and methods ………………………………………………………………….. 48 

Study area ………………………………………………………………………... 48 

Data collection ………………………………………………………………….... 49 

Data analysis …………………………………………………………………….. 49 

Intellectual property agreement/ethical approval …………………………….. 49 

Results and discussion …………………………………………………………………. 52 

Conclusion ……………………………………………………………………………….. 52 

References ……………………………………………………………………………….. 52 

 

 

CHAPTER 3 ……………………………………………………………………………… 55  
SCREENING PLANT EXTRACTS FOR ANTIMIRCROBIAL ACTIVITY …………. 55 
3.1 Introduction …………………………………………………………………………... 55 

3.1.1 Antibacterial activity ………………………………………………………….  55 

3.1.2 Antifungal activity …………………………………………………………… 56 



xii 
 

3.1.3 Antimycobacterial activity ……………………………………………………. 57 

3.1.4 Aim of the study ………………………………………………………………. 58  

3.2 Materials and methods ……………………………………………………………… 58 

3.2.1 Preparation of extracts ………………………………………………………. 58 

3.2.2 Screening for antibacterial activity …………………………………………. 60 

3.2.3 Antifungal screening …………………………………………………………. 61  

3.2.4 Antimycobacterial screening ………………………………………………… 62 

3.3 Results and discussion ………………………………………………………………63 

3.3.1 Antibacterial screening …………............................................................. 63 

3.3.2 Antifungal screening …………………………………………………………. 72 

3.3.3 Antimycobacterial screening ……………………………………………....... 77 

3.4 Conclusion …………………………………………………………………………… 80 

References ……………………………………………………………………………….  81 

 

 

CHAPTER 4 ……………………………………………………………………………… 85  
QUALITATATIVE AND QUANTITATIVE PHYTOCHEMICAL ANALYSIS ………. 85 
4.1 Introduction ……………………………………………………………………………85 

4.2 Aim of the study ……………………………………………………………………… 86 

4.3 Materials and methods ……………………………………………………………… 86 

4.3.1 Plant collection and extraction ………………………………………………. 86 

4.3.2 Qualitative phytochemical analysis …………………………………………. 87 

 4.3.2.1 Test for alkaloids …………………………………………………………. 87 

 4.3.2.2 Test for flavonoids ………………………………………………………. 88 

 4.3.2.3 Test for tannins…………………………………………………………..  88 

 4.3.2.4 Test for anthraquinones …………………………………………………. 88 

 4.3.2.5 Test for saponins ……………………………………………………….... 88 

 4.3.2.6 Test for terpenoids ………………………………………………………. 88 

 4.3.2.7 Test for cardiac glycosides (Keller-killani test) ………………………... 89 

 4.3.2.8 Test for steroids …………………………………………………………. 89 

4.3.3 Quantitative phytochemical analysis ………………………………………. 89 

 4.3.3.1 Preparation of plant extracts ……………………………………………. 89 

 4.3.3.2 Determination of total phenolic content …………………………….…. 89 

 4.3.3.3 Determination of total flavonoid content ………………………………. 90 



xiii 
 

 4.3.3.4 Determination of total tannin content …………………………………... 90 

 4.3.3.5 Determination of total flavonol content ………………………………….91 

4.4 Statistical analysis …………………………………………………………………... 91 

4.5 Results and discussion ………………………………………………………………91 

4.5.1 Qualitative analysis ……………………………………………………………91 

4.5.2 Quantitative analysis ………………………………………………………… 97 

Conclusions………………………………………………………………………………100 

References ……………………………………………………………………………… 100 

 

 

CHAPTER 5 ……………………………………………………………………………. 109 
IN -VITRO ANTIOXIDANT ACTIVITY OF THE PLANT EXTRACTS …………… 109 
5.1 Introduction ………………………………………………………………………… 109 

5.1.1 Plant products as a source of antioxidants ………………………………. 110 

5.2 Aim of the study ……………………………………………………………………. 111  

5.3 Materials and methods ……………………………………………………………. 112 

5.3.1 DPPH radical scavenging activity …………………………………………. 112 

5.3.2 ABTS radical scavenging activity …………………………………………. 112  

5.4 Results and discussion ……………………………………………………………. 113  

5.4.1 DPPH radical scavenging activity …………………………………………. 113 

5.4.2 ABTS radical scavenging activity …………………………………………. 117 

5.5 Conclusions ………………………………………………………………………… 120 

References ………………………………………………………………………………120 

 
 
CHAPTER 6 ……………………………………………………………………………. 123 
ANTI-INFLAMMATORY ACTIVITY OF MEDICINAL PLANTS EXTRACTS USING 
5-LIPOXYGENASE ASSAY …………………………………………………………. 123 
6.1 Introduction ………………………………………………………………………… 123 

6.1.1 Role of arachidonic acid …………………………………………………….124 

6.2 Aim of the study …………………………………………………………………….125 

6.3 Materials and methods …………………………………………………………….125 

6.3.1. 5-Lipoxygenase assay ……………………………………………………. 125  

6.4 Results and discussion …………………………………………………………… 126 



xiv 
 

6.5 Conclusions …………………………………………………………………………130 

References ………………………………………………………………………………131 

 

 

CHAPTER 7 …………………………………………………………………………….135 

IN VITRO CYTOTOXICITY ACTIVITY OF MEDICINAL PLANTS EXTRACTS…135 
7.1 Introduction ………………………………………………………………………….135 

7.2 Aim of the study …………………………………………………………………….137 

7.3 Materials and methods …………………………………………………………… 138 

7.3.1 Plant collection and extraction ……………………………………………. 138 

7.3.2 Plant extracts serial dilution ...……………………………………………...138 

7.3.3 The maintenance of tissue cultures ………………………………………138 

7.3.4 Bio-assay ……………………………………………………………………. 139 

7.3.5 The MTT cell viability test ……………………………………………....... 139 

7.3.6 Statistical analysis …………………………………………………………..140 

7.4 Results and discussion …………………………………………………………... 141 

7.5 Conclusions …………………………………………………………………………162  

References ………………………………………………………………………………162 

 

 

CHAPTER 8 ……………………………………………………………………………. 166 
ISOLATION AND IDENTIFICATION OF BIOACTIVE COMPOUNDS FROM 
KNIPHOFIA DREPANOPHYLLA …………………………………………………… 166 
8.1 Introduction ………………………………………………………………………… 166 

8.2 Materials and methods …………………………………………………………… 168 

8.2.1 Plant collection and bulk extraction ……………………………………….168 

8.2.2 Solvent-solvent extraction ………………………………………………… 168 

8.2.3 Column chromatography ………………………………………………....   171 

8.2.4 Preparative TLC ……………………………………………………………. 171                 

8.2.5 Bioautography ……………………………………………………………… 171 

8.2.6 NMR Spectroscopy ………………………………………………………….172 

8.3 Results and discussion …………………………………………………………….172 

8.3.1 Bulk extraction ……………………………………………………………….172 

8.3.2 Solvent-solvent extraction ………………………………………………….172 



xv 
 

8.3.3 Column chromatography …………………………………………………...173 

8.3.4 Preparative TLC ……………………………………………………………. 173 

8.3.5 NMR analysis ………………………………………………………………. 179 

8.4 Conclusions …………………………………………………………………………178 

References ………………………………………………………………………………181 

 

 
CHAPTER 9 …………………………………………………………………………… 183 
GENERAL DISCUSSION, CONCLUSION AND RECOMMENDATIONS ……… 183 
9.1 General discussion ………………………………………………………………...183 

9.2 Conclusion and recommendations ……………………………………………….187 

References ………………………………………………………………………………188 

 
 
 

  

 

 

 

 

 
 
 
 
 
 

 

 

 

 

 

 

 

 



xvi 
 

LIST OF TABLES 
 
Table 1:     Medicinal plants used for the treatment of elephantiasis in the Eastern    

                  Cape, South Africa …………………………………………………………. 50 

Table 3.1:  Antibacterial activity of traditional medicinal plant extracts used against  

                   elephantiasis in the Eastern Cape (MIC and MBC values in mg/ml)  

                   ………………………………………………………………………………… 69 

Table 3.2:  Antifungal activity of traditional medicinal plants used against 

elephantiasis in the Eastern Cape (MIC and MFC values mg/ml) 

……………………………………………………………………….............. 74 

Table 3.3: Antimycobacterial activity of traditional medicinal plants used against 

elephantiasis in the Eastern Cape (MIC and MBC values in mg/ml) …. 79 

Table 4.1:  Qualitative analysis of the phytochemical constituents of the plants used 

against elephantiasis in the Eastern Cape Province, South Africa ……. 96 

Table 4.2: Phytochemical constituents identified in the extracts of the selected 

medicinal plants ……………………………………………………………. 99 

Table 5.1:   DPPH and ABTS scavenging activity of the medicinal plants ………… 113 
Table 6.1:  The inhibitory activity against the 5-lipoxygenase enzyme of water and                                         

                   ethanol extracts represented by IC50 values ……………………………. 127 
 

 
 
 
 

 

 

 

 

 

 

 

 

 



xvii 
 

LIST OF FIGURES 
 

Figure 1.1: Lymphedema ..........................................................................................1 

Figure 1.2: Manifestation of elephantiasis ................................................................ 2  

Figure 1.3: Hydrocele ............................................................................................... 2 

Figure 1.4: Transmission of elephantiasis……………………………………………… 5 

Figure 1.5: Treatment of elephantiasis …………………………………………………11 

Figure 1.6:  The 5-lipoxygenase pathway and therapeutic potential of 5-

lipoxygenase inhibitors in GI cancers ………………………………….. 24 

Figure 1:    Map of OR Tambo District Municipality showing the study areas .….. 48  

Figure 2:    Plant parts used in the treatment of elephantiasis ………………………51  
Figure 3:    Methods of preparation of the herbal extracts ………………………….. 52 

Figure 3.1: Dried plants were ground into a fine powder using a blender ………….59 

Figure 3.2: Extraction of powdered plant material in the respective solvents was 

performed for 24 hours ….………………………………………………. 60 

Figure 3.3: Water extracts of C. dentata show the lowest inhibition against P. 

aeruginosa at 0.098 mg/ml. The orange circle indicates minimum 

inhibitory concentrations ……………………………………………….…. 64 

Figure 3.4: Figure showing water extracts of G. perpensa active against C. vulgaris 

with the lowest MIC value at 0.098 mg/ml and the arrow shows ethyl 

acetate extract showing the MIC value for all the fungal strains (C. 

albicans, C. vulgaris, T. mucoides) at 0.78 mg/ml ………………………. 77 

Figure 4.1:  Qualitative phytochemical analysis showing test tubes with different 

plant extracts ……………………………………………………………….. 87  

Figure 5.1: DPPH scavenging activity of the water extracts of the medicinal plants 

 ……………………………………………………………………………… 114 

Figure 5.2:  DPPH scavenging activity of the ethanol extracts of the medicinal plants  

…………………………………………………………………………….  

Figure 5.3:  ABTS scavenging activity of the water extracts of the medicinal plants 

                     …………………………………………………………………………….. 118 

Figure 5.4:  ABTS scavenging activity of the ethanol extracts of the medicinal plants  

……………………………………………………………………………. 119 

Figure 6.1:  The percentage inhibition (%) of the 5-lipoxygenase enzyme by the  



xviii 
 

                     water extracts and the reference drug Nordihydroguaiaretic acid  

(NDGA. The error bars represent the standard deviation ………….. 128 
Figure 6.2:   The percentage inhibition (%) of the 5-lipoxygenase enzyme by the 

ethanol extracts and the reference drug Nordihydroguaiaretic acid 

(NDGA. The error bars represent the standard deviation ………….. 129  

Figure 7.1:  Illustration of in vitro and in vivo toxicity ………………………………..136 

Figure 7.2:  Cytotoxicity effects of C. dentata water extract on Hutu-80 cells after (a) 

12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the same letter 

superscript indicates a statistically significant difference between the 

control and the treated cells (Mann-Whitney, p≤0.05) ……………… 144 

Figure 7.3:  Cytotoxicity effects of K. drepanophylla water extract on Hutu-80 cells 

after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05) ..145 

Figure 7.4:  Cytotoxicity effects of R. melanophloeoes water extract on Hutu-80 cells 

after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05 ...146 

Figure 7.5:  Cytotoxicity effects of C. dentata acetone extract on Hutu-80 cells after 

(a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the same 

letter superscript indicates a statistically significant difference between 

the control and the treated cells (Mann-Whitney, p≤0.05 ……………147 

Figure 7.6:   Cytotoxicity effects of K. drepanophylla acetone extract on Hutu-80 cells 

after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the same 

letter superscript indicates a statistically significant difference between 

the control and the treated cells (Mann-Whitney, p≤0.05) 

……………………….……………………………………………………... 148 

Figure 7.7:   Cytotoxicity effects of R. melanophloeos acetone extract on Hutu-80 

cells after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05)   

………….………………………………………………………………….149 
Figure 7.8:  Cytotoxicity effects of C. dentata ethanol extract on Hutu-80 cells after 

(a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the same 



xix 
 

letter superscript indicates a statistically significant difference between 

the control and the treated cells (Mann-Whitney, p≤0.05) …………150 
Figure 7.9:   Cytotoxicity effects of K. drepanophylla ethanol extract on Hutu-80 cells 

after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05)    

……………….……………………………………………………………. 151 
Figure 7.10: Cytotoxicity effects of R. melanophloeos ethanol extract on Hutu-80 

cells after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05) 

……………………………………………………………………………...152 
Figure 7.11: Cytotoxicity effects of C. dentata water extract on H4IIE-luc cells after 

(a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the same 

letter superscript indicates a statistically significant difference between 

the control and the treated cells (Mann-Whitney, p≤0.05) …………. 153 
Figure 7.12: Cytotoxicity effects of K. drepanophylla water extract on H4IIE-luc cells 

after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05) 

…………………………………………………………………………….. 154 
Figure 7.13: Cytotoxicity effects of R. melanophloeos water extract on H4IIE-luc 

cells after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05) 

………………………………………………………………………………155 
Figure 7.14: Cytotoxicity effects of C. dentata acetone extract on H4IIE-luc cells 

after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05) 

…………….………………………………………………………………. 156 
Figure 7.15: Cytotoxicity effects of K. drepanophylla acetone extract on H4IIE-luc 

cells after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 



xx 
 

between the control and the treated cells (Mann-Whitney, p≤0.05) 

……………………………………………………………………………...157 
Figure 7.16: Cytotoxicity effects of R. melanophloeos acetone extract on H4IIE-luc 

cells after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05) 

……………………………………………………………………………. 158 
Figure 7.17: Cytotoxicity effects of C. dentata ethanol extract on H4IIE-luc cells after 

(a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the same 

letter superscript indicates a statistically significant difference between 

the control and the treated cells (Mann-Whitney, p≤0.05) …………159 
Figure 7.18: Cytotoxicity effects of K. drepanophylla ethanol extract on H4IIE-luc 

cells after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05) 

…………………………………………………………………………….160 
Figure 7.19: Cytotoxicity effects of R. melanophloeos ethanol extract on H4IIE-luc 

cells after (a) 12 h; (b) 24 h and (c) 48 h. Bars are means (n=3) and the 

same letter superscript indicates a statistically significant difference 

between the control and the treated cells (Mann-Whitney, p≤0.05) 

………………………………………………………………………………161 
Figure 8.1: A summary of the general approaches in extraction, isolation and  

                   characterization of bioactive compounds from plant extracts………….169 

Figure 8.2: Bio-activity guided isolation process (fractions which showed    

                   antimicrobial activity on the bio-autography assay was further purified       

                   ……………………………………………………………………………….170 

Figure 8.3: TLC chromatogram of K. drepanophylla n-hexane fractions from rhizome 

           under UV. The n-hexane fractions were collected from the column   

                     chromatography and spotted on a TLC plate and developed with n-  

                     hexane: ethyl acetate (8:2) solvent system …………………………….174 

Figure 8.4: The n-hexane combined fractions from the column chromatography were 

                    spotted on a TLC plate and developed with n-hexane: ethyl acetate                             

                     (8:2) solvent system after spraying with anisaldehyde reage………. 175 

Figure 8.5: The n-hexane combined fractions (1-34) from column chromatography                 



xxi 
 

                   were spotted on a TLC plate and developed with n-hexane: ethyl acetate                             

                   (8:2) solvent system. (A) Reference TLC plate under UV light and (B)    
                   TLC plate ……………………………………………………………………176 

Figure 8.6: The preparative TLC chromatogram from the combined fractions (1-34)   

                    potted as a long band onto a TLC plate. An arrow pointing to the scraped   

                      zone. The plate was developed with an n-hexane: ethyl acetate (8:2)  

                    solvent system …………………………………………………………….177 

Figure 8.7: TLC plates of K. drepanophylla rhizome n- hexane fraction. Fractions 1-   

                    34 collected from the silica column chromatography were spotted on TLC   

                    plate and developed with n-hexane: ethyl acetate (8:2) solvent system.   

(A) reference plate under UV-light and (B) TLC plate with S. aureus           

                    bacterial overlay. The arrow shows a clear zone or spot……………….178 

 

 

 

 
 

 

 

 

 

 

 

 

 

 

 

 

 

 
 
 
 
 



xxii 
 

LIST OF ABBREVIATIONS 
 
AIDS- Acquired Immunodeficiency syndrome 

ATTC- American Type Culture Collection  

ABTS - 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid  

Acet - Acetone 

AlCl3 - Aluminium chloride 

CDCl3 - Duarated chloroform 

CHF – Congestive heart failure 

COX – Cyclogenase   

DEC - Diethylcarbamazine 

DMEM- Dubelcco’s modified eagle’s medium  

DMSO – Dimethylsolfoxide 

DNA - Deoxyribonucleic acid 

DPBS - Dulbecco’s phosphate buffered saline 

DPPH- 2,2-diphenyl-1-picryl-hydrazyl  

EtAH – Ethyl acetate 

EtOH – Ethanol 

FBS - Foetal bovine serum  

FTIR – Fourier-Transform Infared Spectroscopy 

GC – Gas Chromatography 

GC-MS – Gas Chromatography Mass Spectroscopy 

GPELF- Global Program to Eliminate Lymphatic Filariasis  

H4IIE-luc - Carcinogenic rat haepatoma cells  

H1NMR - Proton nuclear magnetic resonance  

HPLC - High Performance Liquid Chromatography 

H2SO4 – Sulphuric acid 

Hutu-80 - Human duodenum cancer cells  

IBD – Inflammatory bowel disease 

INT - p-Iodonitrotetrazolium violet  

LC-MS – Liquid Chromatography Mass Spectroscopy 

LF – Lymphatic filariasis 

LOX - Lipoxygenase 

MBC - Minimum bactericidal concentration  



xxiii 
 

MIC – Minimum inhibitory concentration  

MDA – Mass drug administration  

MDR – Multidrug-resistant 

MFC - Minimum fungicidal concentration 

MTT - 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide  

Na2CO3 – Sodium bicarbonate  

NADPH – Nicotinamide adenine dinucleotide phosphate 

NCCLS – National Committee for Clinical Laboratory Standards 

NDGA - Nordihydroguaiaretic acid  

NMR - Nuclear Magnetic Resonance  

NORD – National Organization for Rare Diseases 

NSAIDs- Non-steroidal anti-inflammatory drugs 

OADC - Oleic Albumin Dextrose Catalase  

OR – Oliver Reginald  

QE - Quercetin equivalent  

Rf - Retention factor  

RNA – Ribonucleic acid 

RNS – Reactive nitrogen species 

ROS – Reactive oxygen species 

SC – Solvent control 

TB - Tuberculosis 

UV – Ultraviolet 

WHO - World Health Organisation 

XDR – Extremely drug resistant 

 

 

 
  



1 
 

CHAPTER 1 

 

LITERATURE REVIEW 

 

1.1 Introduction  
Lymphatic filariasis (LF), which has the common name elephantiasis, one of the 

tropical diseases that are of less concern, usually referred to as Neglected Tropical 

Diseases (NTDs) due to infection from parasitic worms and transmitted to humans by 

mosquitoes (WHO, 2010). A condition is characterised by swelling of the lower limbs. 

WHO (2021) states that lymphatic filariasis impairs the lymphatic system, which results 

in aberrant body part growth, pain, severe disability, and social shame. Lymphatic 

filariasis may be asymptomatic, acute or chronic.   

 

 

             Fig 1.1: Lymphoedema (youtube.com). 

 

https://en.wikipedia.org/wiki/Elephantiasis_tropica


2 
 

 
                    Fig 1.2: Manifestation of elephantiasis (daily post. ng). 

 

 

 

                        Fig 1.3: Hydrocele (omicsonline.org). 

 

The asymptomatic infection alters the body's immune system by impairing the 

lymphatic system and kidneys. Acute infection is associated with fever, pain and 

tenderness of the affected area corresponding to the inflamed lymphatic channel.  A 

blockage in lymph flow causes increases more fluid around the tissue spaces, 

resulting in swelling of the part (WHO, 2013). Lymphatic filariasis infections are 



3 
 

classisifed as chronic conditions when there is swelling or skin thickening of the limbs 

and scrotum (WHO, 2021). The affected body parts include the limbs, breasts, and 

genitalia. Lymphoedema occurs after progressive oedema and repeated acute 

attacks. Elephantiasis does not only lead to great personal suffering from its 

debilitating and disfiguring lesions, but it is also a significant factor in socioeconomic 

advancement, both locally and nationally (Ottessen et al., 1997). The most common 

type of elephantiasis is characterised by hydrocele and chronic lymphoedema or 

swelling of the lower and upper limbs and it affects marginalised persons, in particular 

those who reside in places with subpar housing and sanitation, are more susceptible 

to contracting the illness.  

 

South-East Asia has a high prevalence of the disease, therefore strong political 

initiatives and excellent programs led to the eradication in certain areas. Despite the 

disease's modest fatality rate, it poses a substantial threat to global public health since 

it results in significant socioeconomic consequences (WHO, 2005). Neglected tropical 

disease distribution is due to socio-economic factors, great exposure to vectors, 

unclean food and water, reservoir hosts and climate.  

 

Lymphatic filariasis is amongst nine infectious diseases aimed to be eliminated 

globally (Cano et al., 2014). It includes tropical diseases that the World Health 

Organization had set a target to achieve elimination by the year 2020 which led to 

increased vaccine and drug innovations and other alternatives for vector control.    

 

 

1.2 Aetiology of elephantiasis  

The disease is classified into filarial and non-filarial elephantiasis. Where no cause 

has been found, such cases are regarded as idiopathic.   

 

1.2.1 Filarial elephantiasis 

Elephantiasis due to lymphatic filariasis may be referred to as "true" elephantiasis in 

most areas. The three parasitic roundworms Wuchereria bancrofti, Brugia malayi, and 



4 
 

B. timori are the culprits (WHO, 2010; Simonsen, 2009; Simonsen, 2013; Slatko et al., 

2014). According to a report by the World Health Organization (2010), W. 

bancrofti and B. timori differ from B. malayi in structure, symptoms and in regional 

extent. 90% of lymphatic filariasis cases are believed to be caused by W. bancrofti, 

whereas the remaining 10% are brought on by Brugian parasites (WHO, 1992). These 

nematode parasites are spread through various mosquito vector species of the 

following genera: Aedes, Mansonia, Culex, Anopheles, and Ochlerotatus 

(Chakraborty et al., 2013; Cano et al., 2014).  

 

These various mosquito species that bite people act as vectors in various places of 

the world, and biological research into how these vectors interact with their 

surroundings is crucial for identifying the kinds of environments that can sustain the 

spread of parasites (Simonsen, 2013).  

 

Lymphatic filariasis is brought on by W. bancrofti and spread by Anopheles and Culex 

mosquitoes in Africa. Southeast Asia is the only region where brugia malayi may be 

found (WHO, 2013). The huge numbers of minute microfilariae (mf) released by 

mature, fertilized female worms circulate in the blood and, when consumed by a vector 

during a blood meal, grow into infectious larvae in about 10–14 days (Simonsen, 

2013). These move to the mosquito's proboscis where they may spread to humans 

during a later blood meal.  Throughout their stay in the lymphatic system, adult worms 

produce millions of microfilariae that move around the blood (Feasy et al., 2009). Thus, 

the mosquito vectors are crucial to the development and spread of filarial diseases 

(Simonsen, 2013).  

 

https://en.wikipedia.org/wiki/Wuchereria_bancrofti
https://en.wikipedia.org/wiki/Wuchereria_bancrofti
https://en.wikipedia.org/wiki/Brugia_timori


5 
 

 
               
Fig 1.4: Transmission of elephantiasis (The Carter Center).  
 

 
1.2.2 Wolbachia as an endosymbiont  
Wolbachia is an intracellular bacterium that has reportedly been found around the 

tissues of numerous filarial species in its early stages using electron microscopy 

(Kozek et al., 1977; McCall et al., 1999; Slatko et al., 2014) was then identified as 

Wolbachia by molecular methods (Sironi et al., 1995; Slatko et al., 2014).  Wolbachia, 

which was first identified in the sexual organs of Culex mosquitoes, is a member of the 

Rickettsiales order and is closely linked to Anaplasma, Ehrlichia, and Rickettsia. 

(Hertig and Wolbach, 1924; Slatko et al., 2014). These endobacteria that are inherited 

from mothers are obligate mutualists that have coexisted with their filarial hosts 

throughout evolution. If the Wolbachia bacteria discovered in various hosts or various 

invertebrate phyla constitute distinct bacterial species or strains, it is still unknown (Lo 

et al., 2007; Pfarr et al., 2007; Slatko et al., 2014). Wolbachia are present through the 

life cycle of the filarial worms by rapidly increasing once the nematode is introduced 

from the insect vector to the mammalian host. The laboratory studies and human trials 



6 
 

together with evidence that Wolbachia is essential for its filarial hosts and prospective 

novel therapeutic approaches for controlling filarial disease are provided by promising 

anti-Wolbachia antibiotic therapies in in-vitro and in-vivo clinical trials. (Slatko et al., 

2014).  

 

1.2.3 Non-filarial elephantiasis 

In a report by Casteillani (1933), “elephantiasis nostras” is used to desctibe a condition 

that is clinically not different from filarial elephantiasis, but the filarial pathogenesis can 

be certainly not be included as patients showed no microfilariae in the blood. The 

author showed that the condition was from bacteria through the examination of the 

affected inguinal glands arising from lymphangitis and lymphadenitis attacks. The 

detected organisms were separated into Gram-positive cocci of the staphylococcus 

type (Staphylococcus aureus, S. albus, S. viscidus); Gram-positive cocci of the 

streptococcus group, most strains of Streptococcus haemolyticus type; Gram-negative 

cocci of the Micrococcus (coccobacillus) metamyceticus type; and Cocci of the 

Micrococcus myceticus type, which at times manifest to be completely Gram-positive, 

at other times completely Gram-negative, and most times partially Gram-positive 

(Casteillani, 1933). According to a report by National Organization for Rare Disorders 

(NORD) (2009), elephantiasis of the sexual organs can also be the result of sexually 

transmitted diseases, particularly lymphogranuloma venereum and donovanosis. 

Lymphogranuloma venereum is caused by Chlamydia trachomatis whereas the 

bacterium Calymmatobacterium (Klebsiella) granulomatosis is responsible for 

donovanosis. Due to the body's immune system's reaction to the bacterium during 

donovanosis, the lymphatic channels become inflamed and constricted, which results 

in genital elephantiasis. 

 

Non-filarial elephantiasis is also associated with podoconiosis, which is caused by 

factors in the environment such as contact with certain minerals in the soil such as 

silica through barefeet. The growth of inflammatory tissues and nodules in the lymph 

vessels of the feet and legs is thought to be a result of the immune system's reaction 

to the mineral compounds (NORD, 2009). Non-filarial elephantiasis also includes a 



7 
 

protozoan condition called leishmaniasis, tuberculosis, leprosy and repeated 

streptococcal infections. It might also happen following radiation, surgery, or trauma. 

 

 

1.3 Transmission of elephantiasis  

Nematodes carried by insect vectors like W.  bancrofti, B. malayi, and B. timori are the 

causes of lymphatic filariasis. (Simonsen, 2009; Simonsen, 2013; Slatko et al., 2014). 

W. bancrofti causes Bancroftian filariasis and is responsible for ninety percent those 

affected by lymphatic filariasis whilst the rest are caused by Brugian parasites (WHO, 

1992). These two; W. bancrofti and B. timori distinguish B. malayi from both of them 

in terms of structure, symptomology, and geographic distribution. (WHO, 2010). By 

depositing infected larvae on human skin, these parasitic organisms spread to people 

via mosquito vectors, where the larvae then enter the skin and move to the lymphatic 

arteries, where they finally mature into male and female adult worms over several 

months. (Simonsen et al., 2013). These nematode species are spread via a variety of 

mosquito vector species belonging to the following genera; Aedes, Culex, Mansonia, 

Anopheles and Ochlerotatus (Cano et al., 2014; Chakraborty et al, 2013). When 

mature female worms are fertilized, a huge number of minute microfilariae (mf) are 

released into the bloodstream. When a vector consumes the microfilariae during a 

meal, they develop into infectious larvae in around 10 to 14 days (Simonsen, 2013). 

Millions of microfilariae that circulate in the blood are produced viviparously by adult 

worms that lodge in the lymphatic system, where they live for years (Feasy et al., 

2009).  

 

 

 
1.4 Prevalence of elephantiasis  
Elephantiasis, a major public health concern amongst several warm countries having 

warm climates (Simonsen et al., 2013). Also, it takes second place in causes of 

disabilities worlwide as about 40 million people who suffer from issues that prevent 

people from engaging in their jobs, pursuing their education, finding work, and moving 

around (WHO, 2013a). More than 100 million people in the Americas, Asia, Africa, and 



8 
 

the Pacific are infected with W. bancrofti, the most prevalent lymphatic filarial parasite 

of humans (Simonsen, 2009). The World Health Organization calculated that more 

than 1.25 billion individuals in 72 countries and territories are at risk in 2013. It was 

estimated that around 40 million people had pathologic symptoms from filarial 

parasites, including the displeasing elephantiasis, and that about 120 million people 

were affected (Babu and Nutman, 2014). This includes 25 million men with urogenital 

swelling, including scrotal hydrocele, and 15 million persons with lymphoedema 

(elephantiasis) (WHO, 2010). A major step that was taken towards the elimination of 

lymphatic filariasis with only a few implementation units (IUs) having remained in Côte 

d'Ivoire, Ethiopia, Nigeria, and Zambia, all implementation units (IUs) in the African 

area had their mapping completed. By the end of 2013, 655 IUs in 17 countries 

targeted for mapping to determine the need for mass drug administration (WHO, 

2013a).  
 

According to research done by Cano et al. (2014), 66 out of 72 countries are said to 

be currently endemic to lymphatic filariasis. It is in 17 countries where lymphatic 

filariasis no longer exists but is now found mainly in coastal areas of east and southern 

Africa (Cano et al., 2014).  

 

Transmission of lymphatic filariasis occurs throughout the Americas region, primarily 

in north and north-east of South America, Central America, the major Caribbean 

islands (Haiti and the Dominican Republic), and sporadically in the southern United 

States (Cano et al., 2014).  Twenty countries in the Americas have eliminated 

lymphatic filariasis, and the only remaining endemic areas are Brazil, Guyana, and 

Hispaniola (the Dominican Republic and Haiti) (Addiss and Chuke, 2002; Cano et al., 

2014).  Transmission is anticipated to occur in eastern India, Sri Lanka, much of 

southeast Asia, southeast China, Papua New Guinea, the northern coast of Australia, 

and southern Japan in Asia and the western Pacific. LF has been eliminated in China 

(2007), Japan (the 1980s), and South Korea (2008), but the predicted environmental 

factors correspond with the known historical and pre-control distribution (Sasa, 1976; 

Kimura et al., 2005; Tada, 2011; Cano et al., 2014). 

 



9 
 

In Arica, lymphatic filariasis is also distributed across countries such as Tanzania with 

an estimation of 6 million people with disabilities because of the disease (Lupenza et 

al., 2021).  

 

According to immunochromatographic card tests (ICT) and microfilaria (Mf) results, 

the number of people in Nigeria with lymphatic filariasis was previously believed to be 

8.7 million and 3.3 million, respectively. (Eneanya, et al., 2019).   

 

Thirty million individuals in Ethiopia were considered to be at risk for lymphatic 

filariasis, placing Ethiopia in fourth place (7.8%) among sub-Saharan African 

countries (Deribe et al., 2012).   

 

The largest prevalence of podoconiosi or  non-filarial elephantiasis, is seen in tropical 

African nations, with 500,000 more individuals living with the disease in Cameroon 

and about 1 million in Ethiopia. (Deribe et al., 2016). High prevalences of 

podoconiosis are found in the highlands of Uganda, Tanzania, Kenya, Rwanda, 

Burundi, Sudan, and Ethiopia (Pietro et al., 2010).  

 

 

 

1.4  Management and treatment of elephantiasis (LF) 
In order to eradicate lymphatic filariasis, minimize morbidity, and prevent related 

disabilities, the Global Program to Eliminate Lymphatic Filariasis (GPELF) was 

established in the year 2000 (WHO, 2010). The GPELF's main goal was giving access 

to hydrocele surgery, stop the growth of lymphedema and elephantiasis, as well as 

debilitating and painful episodes of acute adenolymphangitis or acute 

dermatolymphangioadenitis in areas where lymphatic filariasis is common (WHO, 

2010). By using preventive chemotherapy, such as mass drug administration, the 

provision of anti-filarial medications assisted in the elimination of any remaining worms 

and microfilariae (WHO, 2013b).  

 

By the year 2014, 73 countries were listed as regions where to lymphatic filariasis is 

found and 18 countries entered the monitoring phase and only 11 countries had not 

yet commenced mass drug administration programmes (Molyneux et al., 2016). An 



10 
 

estimate of the year 2014 assessin mass drug administration had suggested that more 

than 96.71 million cases of the disease had been prevented or treated, yet about 36 

million files belonging to hydrocoele and lymphoedema infection had remained 

(Ramaiah and Ottessen, 2014). 

 

The discovery that Wolbachia species play a substantial role in the life cycles of B. 

malayi and other nematodes has inspired the development of brand-new medications 

that target the endobacterium. By preventing larvae from moulting and microfilariae 

from developing, tetracyclines, rifampicin and chloramphenicol demonstrated their 

efficiency in vitro. Tetracyclines have been shown to produce anomalies in adult 

worms' embryogenesis and reproduction, which causes the worms to become infertile. 

Clinical trials have successfully reduced Wolbachia and microfilariae in onchocerciasis 

and W. bancrofti infected patients, and although antibiotics act in a somewhat indirect 

manner, they represent a source of promising antifilarial medicines (Ottesen et al., 

1997). The length of treatment and population-specific contraindications of 

doxycycline offer obstacles to its application in mass medication administration, 

necessitating the development of novel anti-Wolbachia medicines (Slatko et al., 2014; 

Taylor et al., 2014). 

 

Lymphatic filariasis control took a turn-around in the 1990s when advances were made 

in diagnositic studies about of lasting effective drugs in one-dose administrations 

which led to the development of a yearly bi-drug, one-dose mass treatment for 

controlling or elimination of lymphatic filariasis (Ottessen et al., 1997 and Ottessen 

2000). The medications chosen for the management of filariasis include ivermectin, 

albendazole (ALB), and diethylcarbamazine (DEC), which are currently administered 

in large quantities through national programmes (Ottessen, 2000; Gayen et al., 2013; 

Ramaiah and Ottessen, 2014). In most endemic locations, DEC and ALB are 

employed; however, in some parts of Africa, where onchocerciasis and bancroftian 

filariasis are both present, ivermectin and ALB are combined (Molyneux, 2003; 

Ichimori and Ottesen, 2011).   The program's primary approach has been two-fold: to 

begin mass drug administration tactics in endemic areas in order to completely 

interfere with transmission, and to provide effective morbidity management in order to 

lessen suffering in those who have already contracted lymphatic filariasis (Ramaiah 

and Ottessen, 2014).  



11 
 

 

 
 

                     Fig 1.5: Treatment for elephantiasis (who. int). 

 

The programme to implement mass drug administration targeting lymphatic filariasis 

by the GPELF had run a period of 13 years operation by 2012 and it has had a big aim 

of LF elimination by 2020. Furthermore, the GPELF provides mass drug administration 

using albendazole + either ivermectin or diethylcarbamazine to whole endemic 

populations at yearly periods of 4 to 6 years. According to Stolk et al. (2006), if 

programms like this are conducted in a good way by treating at least 65% of the total 

population, each MDA could create the possibility of interrupting transmission and 

eliminating lymphatic filariasis (Stolk et al., 2006).  

 

For microfilaremia, 2 of the main antifilarial medicines in mass drug administration 

efforts which are DEC and ivermectin were recognised to display significant and more 

responses against increasing microfilaremia. The anti-microfilarial effect of these 

drugs is further strengthened when they are taken in combination with ALB, a multi 

spectrum antihelminth medicine that acts by affecting both adult worm survival and 

production of microfilariae (Gyapong et al., 2005). 

   

de Kraker et al. (2006) stated that 4 to 6 times of one dose of DEC can can result in a 

reduction of microfilaremia numbers by up to 86% (Bockarie et al., 2002; Ramaiah et 

al., 2002).  When two principal anti-filarial drugs used in GPELF are combined, (ALB+ 

DEC) or (ALB+ ivermectin), LF infection levels are highly reduced (Ramaiah and 

Ottessen, 2014).  



12 
 

 

However, the main consequences of treatment through anti-filarial drugs are less 

significant against chronic conditions symptoms than on microfilaremia. Many studies 

have proven that treatment has a remarkable impact on chronic disease 

manifestations, starting from the curing of early disease signs and symptoms to the 

actual curing of some chronic lesions. The presence of adult worms alone is sufficient 

to cause hydrocele (Dreyer et al., 2000). Reducing adult worm burden alone can lead 

to reducing hydrocele condition numbers. The anti-filarial drugs used in the MDA 

programme, ALB + ivermectin, as well as DEC alone or with ALB can partially act 

against adult worms and lessening adult worm problem (Ottessen, 1985; Ismail et al., 

1998). Ottesen et al. (1997) and Sashidhara et al. (2012) also reported that drugs used 

may reduce microfilariae numbers but show no effect in killing adult worms. Therefore, 

these drugs provide only partial benefit to infected patients and usually are associated 

with adverse reactions. 

 

Regardless of the success of these programs, no doubt that a need exists to develop 

better and innovative methods for the longer control of adult worms as they are primary 

causes disease pathogenesis in lymphatic filariasis.  New compounds are to be 

discovered agents that will kill the adult worms (microfilariae), replacing current drugs 

that might not work in drug resistant worms as reported in onchocerciasis patients 

against in vitro maturation. The discovery of anti-filarial drugs followed by validation 

through standard experiments is of high importance for the development of screening 

systems that will lead to new anti-filarial compounds. The gene-sequence encoding 

for filarial nematodes and application of RNA interference (RNAi) is also of impotance 

in investigating various gene functions (Singh et al., 2010).   

 

DEC has been reported to cause side effects such as fever, gastrointestinal 

disturbance, headache, malaise, and a skin rash that reduce patient compliance 

(Sharma, 1990; Babu et al., 2006). Adverse reactions following treatment with 

ivermectin usually are not manifestations of direct drug toxicity but result from host 

inflammatory responses to the very rapid clearance of microfilariae from the blood. 

The most common side-effects include fever, light-headedness, malaise, and, in 

extreme cases, postural hypotension which develops between 12-24 h post-treatment 

and lasts for an additional 24-36 h in approximately half of the microfilaremia patients 



13 
 

treated (Ottesen and Campbell, 1994). Other reported side effects of ivermectin 

include itching after early administration, acute toxicities such as convulsions after 

overdosage and deaths that have been reported in patients that were treated for 

filariasis (Fujimoto et al., 2014).  

 

Treating bancroftian filariasis with a 4 to 6, or 8-week course of 200 mg per day dose 

of doxycycline will result in long-term sterility and eventual death of the adult worms 

(Hoerauf, 2008; Bockarie et al., 2009). Furthermore, lab and human trials demonstrate 

that depletion of Wolbachia in filarial parasites by antibiotics like doxycycline and 

tetracycline work to kill the adult worms in addition to blocking embryogenesis, 

microfilariae production and worm development (Foster et al., 2013; Slatko; Taylor et 

al., 2014).  

 

  

 
1.6 Medicinal plants in the treatment of elephantiasis 

The demand and scarcity of medicine that can prevent disease and the problem of 

drug-resistant worms has put pressure on an urgent need for cheaper novel anti-filarial 

drugs with long-term antimicrofilarial or macrofilaricidal activity and less side-effects 

(Srivastrava et al., 2000; Dharma et al., 2005). Some medicinal products have been 

discovered from plants which are utilised in traditional medicine. Many medicinal 

plants containing pentacyclic triterpenes and oleanolic acids have been reported to 

possess anti-filarial activity (Misra et al., 2007). Plant drugs which can act against 

filariasis were discovered from plants that are used in traditional medicine.  

 
In the Americas, Piper aduncum and P. elongatum are in the list of plants used in 

Brazil for  lymphatic filariasis management by acting against filarial worms (Ndjonka 

et al., 2013). In India, Butea monosperma, Lantana camara and Vitex negundo have 

been reported to act against filarial worms (Anil and Talluri, 2015). Andrographis 

paniculata has been reported to be used in greater Asia including China, India and Sri 

Lanka (Al-abd et al., 2013). In West Africa, Acacia nilotica and Bombax buopozense 

are used in Central Nigeria, and Spathodea campanulate and Newbouldia leavis are 

used in Ghana (Ndjonka et al., 2013; Twumasi et al., 2020); in East Africa, Warburgia 

salutaris is used in Tanzania (Ndjonka et al., 2013). Azadirachta indica is used in India 



14 
 

and West Africa; and Cardiospermum halicacabum is used around tropical and 

subtropical regions of Africa and Asia (Al-abd et al., 2013).   

 

Studies by Al-and et al. (2013) and Komoreng et al. (2017) and reported the use of 

Ricinus communis in South Africa and India for the treatment of the disease.  

Euphorbia clavarioides, Euphorbia gorgonis, Rumex obtusifolius, Rhoicissus 

tomentosa and Rhoicissus tridentata are also used to treat conditions associated with 

lymphatic filariasis in South Africa (Komoreng et al., 2017).  

 
 
 
1.7 Use of medicinal plants in South Africa 
Plants have been used as medicine for thousands of years (Samuelsson, 2004; 

Balunas and Kinghorn 2005). These natural products medicines were in the form of 

crude extracts such as tinctures, teas, poultices, powders and other herbal 

formulations (Balick and Cox, 1997; Samuelsson, 2004). South Africa has a long 

history of traditional plant use for the treatment and mangement of various diseases 

and conditions (Cunningham, 1993; Van Wyk et al., 1997; Amoo et al., 2009). Large 

numbers of populations in second world countries use traditional medicine as a 

primary healthcare are resource due to the value of Western medicine and healthcare, 

and because traditional medicines are generally more acceptable from a cultural and 

spiritual point of view (Addae-Mensah, 1992; Amoo et al., 2009).  

 

80% and more of the world’s population are estimated to use use plants as their main 

source of medicine (Cordell, 1995; Taylor et al., 2003;). In South Africa, 60%–80% of 

the population mainly or partially use traditional herbal medicines to treat a variety of 

animal and human diseases (Dausdart, 1990; Shai et al., 2008). Up to 60% of the 

population consults traditional healers, especially in rural areas where traditional 

doctors are many and more easily accessible than Western healthcare (van Wyk et 

al., 1997; Taylor et al, 2003).  Large numbers of medicines used on a daily basis in 

South Africa are derived from plants where large volumes of plants, or their extracts, 

are so found in both the informal and commercial sectors of the economy (Taylor et 

al., 2009).  With the increasing use of traditional medicine by indigenous people, 

investigating biologically active agents based on traditional use relevant as these 



15 
 

plants possess the potential to provide pharmacologically active compounds (Cragg 

et al., 1997; Eldeen and van Staden, 2007; Amoo et al, 2009).  

 

Drugs found in plants are an important source of new chemical prroducts with 

therapeutic effects against pain (Farnsworth, 1889; Gupta et al., 2006; Nkomo et al., 

2010). Several studies documented over 3000 plant materials which added to the 

knowledge that includes current ways adaptations and mechanisms with indigenous 

materials in South African traditional medicine (van Wyk et al., 2009; Philander, 2011). 

Our country possesses various types of ethnomedicine with medicinal plant having 

been been documented in various cultures (Philander, 2011). KwaZulu-Natal Province 

has 1032 plant species recorded as Zulu medicinal plants, and studies from the 

Eastern Cape discovered that Xhosa people frequently use plants that are of 

medicinal, cultural or spiritual importance (Hutchings et al., 1996; Cocks and Dold, 

2002; Dold and Cocks, 2006; Philander, 2011).  

 

 

 
1.8 Major groups of plant secondary metabolites 
Plants are stationary autotrophs having to adapt to several environmental factors 

which include manufacturing pollination and seed dispersal, localised fluctuations in 

nutrient supply they need for food synthesis and their coexistence with herbivores and 

pathogens in their immediate environment. Plants, therefore evolved secondary 

biochemical pathways giving them the ability to produce structures of chemicals, often 

in response to specific environmental stimuli, such as herbivore-induced damage, 

pathogen attacks or nutrient deprivation (Hermsmeier et al., 2011; Kennedy and 

Wightman, 2011; Reymond et al., 2000). As a result of these response mechanisms 

to external stimuli, plants have become a source of natural products that possess the 

potential to produce new types of drugs that are of great benefit to humans (Karimi et 

al., 2011) Highly important of these bioactive constituents, which are mainly secondary 

metabolites, are alkaloids, saponin, flavonoids, tannins, and phenolic compounds, 

Plant by-products are chemically and taxonomically extremely diverse compounds 

whose function has not yet been discovered. These compounds are widely used in 

human therapy, veterinary, agriculture, scientific research, and countless other areas 

(Yadav and Agarwala, 2011; Vasu et al., 2009). A large number of phytochemicals 



16 
 

belonging to several chemical classes have been shown to have inhibitory effects on 

all types of microorganisms in vitro (Cowan, 2009; Yadav and Agarwala, 2011). The 

sub-groups of these phytochemicals include phenols, phenolic acids, 

phenylpropanoids, flavonoids, flavones, glycoflavonones and biflavonols, minor 

flavonoids, aurones, flavonones, isoflavones, xanthones and stilbenes, hydrolysable 

and condensed (proanthocyanidins) tannins and quinines (Muchuweti et al., 2007 

Strack, 1997; Harbone 1998). 

 
 
 
 
1.8.1 Phenolic compounds 
 
Phenolic compounds are secondary plant metabolites that structurally share leastly 1 

aromatic hydrocarbon ring with 1 or more hydroxyl groups attached (Kennedy and 

Wightman, 2011).  Phenolic compounds dissolve in water and may occur attached 

with a sugar molecule, as glycosides (Harborne, 1998; Muchuweti et al., 2007). They 

have a diverse biological activity including toxicity to hormonal mimicry and act as part 

of cell wall material, colourful attractants for birds and insects helping seed dispersal 

and pollination, and their compounds also act as defense mechanisms of plants under 

different environmental stress conditions such as wounding, infection, excessive light 

or UV irradiation (Harbone, 1998). Phenolics startbfrom simple low-molecular-weight 

compounds such as the simple phenylpropanoids, coumarins and benzoic acid 

derivatives, to more complex structures such as flavonoids, stilbenes and tannins. The 

biological potency of phenolic compounds includes important pharmacological 

compounds (Ingold, 1960; Muchuweti, 2007). Phenolic compounds at large have long 

been recognised to possess antiallergenic, anti-inflammatory, antiviral and 

antiproliferative activities (Muchuweti et al., 2007). About 12 000 phenolic compounds 

have been isolated, a number estimated to be just less than 10 % of the total number 

(Borris, 1996; Cowan, 1999). The phenolic acids  as primary antioxidants having a 

single or more aromatic rings bearing one or more hydroxyl groups can quench free 

radicals by forming stabilized phenoxyl radicals ( (Takaidza et al., 2018).  

 

 

   



17 
 

1.8.2 Flavonoids 
The flavonoids represent the largest and most diverse group of phenols, with about 

6000 compounds sharing a common unique structure of two 6-carbon rings. They 

have low molecular weight. Flavane is an example of a flavonoid and it contains two 

benzene rings within its chemical composition (Altemimi et al., 2017). Flavones, 

isoflavones, flavonoids, flavonols, flavanones, anthocyanins and proanthocyanidins 

are part of flavonoids according to the flavonoid classification. Flavonoids were found 

to possess several pharmacological properties, including antioxidant, free radical 

scavenging abilities, anti-inflammatory and anti-carcinogens (Scalbert and Williamson, 

2000; Manach et al., 2004 & Wulandari et al., 2016).  

 

Flavones are phenolic structures containing one carbonyl group (as opposed to the 

two carbonyls in quinones); the addition of a 3-hydroxyl group yields a flavonol 

(Fessenden and Fessenden, 1982). Flavonoids are also hydroxylated phenolic 

substances but occur as a C6-C3 unit linked to an aromatic ring. Since they are known 

to be synthesized by plants in response to microbial infection it should not be surprising 

how they can be effective against antimicrobial substances against a wide range of 

microorganisms (Dixon et al., 1983; Cowan, 1999). Activity is probably due to their 

ability to complex with extracellular and soluble proteins and to complex with bacterial 

cell walls (Cowan, 1999). More lipophilic flavonoids may also disrupt microbial 

membranes (Tsuchiya et al., 1996). Catechins, which are the most reduced form of 

the C3 unit in flavonoid compounds, are very relevant in the flavonoid group. These 

flavonoids were extensively investigated for their presence in green tea, and it was 

found that teas possessed antimicrobial activity because they have a mixture of 

catechin compounds (Toda et al., 1989; Cowan, 1999;). The catechins were also 

reported to have acted against cholera toxin in Vibrio and also inhibited isolated 

bacterial glucosyltransferases in S. mutans possibly due to complexing activities 

described for quinones (Nkahara, 1993; Borris, 1996; Cowan, 1999). Flavonoid 

compounds have inhibitory effects against multiple viruses and numerous studies 

have documented the effectiveness of flavonoids such as swertifrancheside, 

glycyrrhizin (from liquorice) and chrysin against human immunodeficiency virus 

(Pengsuparp, 1995; Critchfield et al, 1996, and Watanbe, 1996). Studies discovered 

flavone derivatives are inhibitory to the respiratory syncytial virus (RSV) (Kaul et al., 

1985; Barnard et al., 1993). A summary of the antiviral effects and modes of action of 



18 
 

quercetin, naringin, hesperetin and catechin in in-vitro cell culture monolayers were 

also reported by Kaul et al (1985). 

      
 
 
1.8.3 Tannins  
Tannins are natural products found in many plant families, possessing large numbers 

of phenolic rings in their structure. Being polymeric substances, they can tann leather 

or precipitate gelatine from solution, a property known as astringency (Cowan, 1999; 

Altemimi et al., 2017). They represent the major groups of antioxidant polyphenols 

found in food and beverages which have drawn a lot of attention in recent years 

because of their multifunctional properties that are beneficial to human health (Kumari 

and Jain, 2012). Tannins have earned a lot of attention in recent years as it was 

suggested that the consumption of tannin-containing beverages, especially green teas 

and red wines, can cure or prevent a number of diseases (Serafini et al., 1994). Many 

human physiological processes, such as stimulation of phagocytic cells, host-

mediated tumour activity and a wide range of anti-infective actions have been 

associated with tannins (Haslam, 1996). A part of their molecular actions is to combine 

with proteins through so-called non-specific forces such as hydrogen bonding and 

hydrophobic effects, as well as by covalent bond formation (Haslam, 1966; Stern et 

al., 1996; Cowan, 1999). Thus, their mode of antimicrobial action may be attributed to 

their ability to inactivate microbial adhesins, enzymes, cell envelope transport proteins 

and many other activities (Cowan, 1999). They also form a complex with 

polysaccharides (Ya et al., 1988).  Scalbert (1991) reviewed the antimicrobial 

properties of tannins and he listed 33 studies that had documented the inhibitory 

activities of tannins. According to these studies, tannins were reported as toxic to 

filamentous fungi, yeasts, and bacteria. 

 

They are classified into two groups, hydrolysable and condensed or proanthocyandins. 

Hydrolysable tannins are a mix of simple phenols with ester linkages in structure based 

on gallic acid, usually as multiple esters with D-glucose, while the more numerous 

condensed tannins are derived from flavonoid monomers (Cowan, 1999; Altemini et 

al., 2017). According to Kumar and Jain (2012), hydrolysable tannins are molecules 

with a polyol (D-glucose) as a central core. The hydroxyl groups of these 



19 
 

carbohydrates are partially or esterified with phenolic groups like gallic acid 

(gallotannin) or ellagic acid (ellagitannin) and are usually present in low amounts in 

plants and can also be easily hydrolysed by mild acids and bases to yield carbohydrate 

and phenolic acids. Condensed tannins possess flavonoid monomers with several 

degrees of condensation. In nature they occurr as polyphenolic bioflavonoids, 

specificallly taking the form of oligomers or polymers of polyhydroxy flavan-3-of units, 

such as (+)-catechin and (-)-epicatechin and flavan-3,4-diols, such as 

leucoanthocyanidins or a mixture of the two (Porter, 1986; Kumar & Jain, 2012).  

 

Alkaline compounds, mineral acids, and enzymes are some of the factors that can 

hydrolyse tannins (Altemimi et al., 2017). Plant part such as bark, wood, leaves, fruits, 

and roots possess tannins (Scalbert, 1991; Cowan, 1999 Kumar and Jain, 2012). 

Condensed tannins can bind cell walls of ruminal bacteria, preventing growth and 

protease activity (Jones et al., 1994). Condensed tannins are widely distributed in 

fruits, vegetables, forage, plants, cocoa, red wine, and certain food grains, such as 

sorghum, finger millets, and legume, possessing cardio-protective, anti-inflammatory, 

anti-carcinogenic, and antimutagenic, among others. These protective properties are 

related to their antioxidant capacity to act as free radical scavengers by activating 

antioxidant enzymes (Kumar and Jain, 2012).  

 
 
 
1.8.4 Alkaloids 
Alkaloids are heterocyclic nitrogen compounds that are diverse in structure. Over 12 

000 cyclic nitrogen-containing compounds are found in over 20% of plant species 

(Zulak et al., 2006; Kennedy and Wightman, 2011). Although a single classification 

does not exist, structural similarity distinguishes them i.e., indole alkaloids or a 

common precursor and benzylisoquinoline, tropane, pyrrolizidine, or purine alkaloids 

(Kennedy and Wightman, 2011).  

 

Morphine was recorded first in medicinal use as an alkaloid isolated in 1805 from the 

opium poppy Papaver somniferum (Fessenden and Fessenden, 1982; Cowan, 1999). 

Diterpenoid alkaloids, commonly isolated from the plants of the Ranunculaceae family, 

are commonly found to have antimicrobial properties (Rahman and Choudary, 1995; 



20 
 

Omulokoli et al., 1997; Cowan; 1999). Berberine as an important example of the 

alkaloid grouppotenti was discovered to be effective against trypanosomes and 

plasmodia (Freiburghaus et al., 1996; Omulokoli et al., 1997).   

 

The recorded use of alkaloids for medicinal purposes stretches back some 5000 years 

ago (Kennedy and Wightman, 2011; Goldman, 2001). This chemical group has 

contributed to the majority of the poisons, neurotoxins and traditional psychedelics 

(e.g., atropine, scopolamine, and hyoscyamine, from the plant Atropa Belladonna and 

social drugs e.g., nicotine, caffeine, methamphetamine (ephedrine), cocaine and 

opiates that are consumed by humans (Zenk and Juenger, 2007; Kennedy and 

Wightman, 2011). Some herbivorous species evolved to adapt to either tolerate or 

sequester alkaloids from their host plant. Plant-based alkaloids are however toxic to 

mammals by their function and chemical nature (Rattan, 2010). 

 
Alkaloids such as isoquinoline, quinolone, and β-carboline type possess several 

antiviral compounds e.g., sanguinarine and berberine are strong DNA intercalators 

that have antibacterial, antiviral and cytotoxic properties (Wink, 2020).  

 

 

1.8.5 Saponins 
Saponins are a diverse group of phytochemicals whose chemical structures are 

composed of a fat-soluble nucleus (aglycone) which is either a triterpenoid (C-30) or 

a neutral or alkaloid steroid (C-27) attached to one or more water-soluble sugars 

(glycone) side chains through ester linkages to the aglycone nucleus at different 

carbon sites (Haralampidis et al., 2002; Karimi et al., 2011. Saponins with one sugar 

molecule attached at the C-3 position are called monodesmoside saponins, and those 

that have a minimum of two sugars, one attached to the C-3 and one at C-22, are 

called bidesmoside saponins (Laziszity et al., 1998; Adams, 2014). While steroid 

saponins are more prevalent in yucca, tomato, and oats, triterpenoid saponins are 

more prevalent in soybean, alfalfa, and quillaja While steroid saponins are more 

prevalent in yucca, tomato, and oats, triterpenoid saponins are more prevalent in 

soybean, alfalfa, and quillaja (Haralampidis et al., 2002; Karimi et al., 2011).  

 



21 
 

Some biological properties of saponins include haemolytic and antibacterial activities 

(Sparg et al., 2004). As the most popular member of the Araliaceae family, Panax 

ginseng root preparations have a lengthy medical history (Yun, 2001). The putative 

major active components comprise 40 or more species-specific triterpene saponins 

known as ginsenosides (Lu et al., 2009). The ginsenosides in plants possess 

antifungal, viral, bacterial, insecticidal and molluscicidal activity and exert allelopathic 

and antifeeding effects (Osbourn, 1996; Sparg et al., 2004; Kennedy and Wightman, 

2011). 

 
 
1.8.6 Terpenes 
Terpenes are a diverse group of more than 30,000 lipid-soluble compounds. Their 

structure includes 1 or more 5-carbon isoprene units. They are classified according to 

the number of isoprene units they contain. Isoprene itself is synthesized and released 

by plants and if it comprises 1 unit it is classified as a hemiterpene, monoterpenes 

incorporate 2 isoprene units, sesquiterpenes incorporate 3 units, diterpenes comprise 

4 units, sesterpenes include 5 units, triterpenes incorporate 6 units and tetraterpenes 

8 units (Kennedy and Wightman, 2011).  Terpenes exhibit a level of toxicity that ranges 

from lethal to entirely edible, and this is in keeping with their wide range of ecological 

functions, which include pollination, seed dispersal, and secondary protective roles 

(Kennedy and Wightman, 2011). Terpenoids also exhibit a number of noteworthy 

pharmacological properties, including anti-inflammatory, anti-cancer, anti-malarial, 

cholesterol synthesis inhibition, antiviral, and antibacterial properties (Mahato and 

Sen, 1997; Wadood et al., 2013).  

 

 

1.9 Phytochemicals as antioxidants and their free radical scavenging ability  
Free radicals are defined atoms or molecules possessing unpaired electrons. The 

reactive oxygen species are oxygen-derived free radicals such as superoxide anion 

(O2), hydroxyl (OH), hydroperoxyl (ROOH), peroxyl (ROO), alkoxyl (RO) radicals, and 

non-free radicals such as hydrogen peroxide (H2O2), hypochlorous acid (HOCl), ozone 

(O3) and by singlet oxygen (O2) (Halliwell and Gutteridge, 1999; Paulsamy et al., 

2016).  They are formed in living organisms endogenously by respiration, peroxisomes 

stimulation of polymorphonuclear leucocytes and macrophages, and exogenously by 



22 
 

ionizing radiation, tobacco smoke, pollutants, pesticides and organic solvents (Irshad 

and Chaudhuri, 2002; Paulsamy et al., 2014). Free radicals are produced by our 

bodies to stabilize the body’s natural function, but the problem is that the excess 

amount can cause cell and tissue damage (Sen et al., 2010). Additionally, they can 

result in oxidative damage to proteins, lipids, and DNA as well as chronic human 

disorders like cancer, diabetes, aging, and other degenerative conditions (Aiyegoro 

and Okoh, 2010).  

  

Antioxidants can further be defined as any chemical that prevents or reduces oxidative 

damage to a target molecule. defined as any substance that delays or inhibits oxidative 

damage to a target molecule (Yamagishi and Matsui, 2010). Due to their redox 

hydrogen donors and singlet oxygen quenchers, antioxidants have the potential to 

scavenge free radicals, which is a defining attribute of an antioxidant (Anokwuru et al, 

2011; Wu et al., 2011; Paulsamy et al, 2014).  Both natural antioxidants and plants 

can scavenge free radicals (butylated hydroxyl toluene, butylated hydroxyl anisol and 

tetra butyl hydro quinone) (Mbaebe et al., 2012). Chemical antioxidants are now being 

currently replaced by natural antioxidants since the natural ones are considered to 

have the potential of being safer with less or no side effects (Meenakshi et al., 2011; 

Paulsamy et al., 2014). Plants include advantageous phytochemicals that can act as 

natural antioxidants to complement the body's needs (Boots et al., 2008). Many 

researchers through the years have been interested in the investigation of medicinal 

plants' phytochemicals for their antioxidant potential to scavenge free radicals that 

cause human disease.  

 

Many antioxidant compounds are known to be found in fruits and vegetables and these 

include vitamins A and C, phenolics such as flavonoids, tannins and lignins, 

carotenoids, anthocyanins and tocopherols (Jakubowski and Bartosz, 1997; Suffredini 

et al., 2004; Altemimi et al., 2017). Therefore, eating fruits and vegetables has been 

linked to health advantages due to their therapeutic characteristics and high nutritional 

content (Valko et al., 2006). 

   

Demand for non-toxic, natural preservatives, many of which are expected to have 

either antioxidant or antibacterial activity, has increased as awareness of the 

detrimental effects of synthetic preservatives has grown (Negi et al., 2005; Baharlouei 



23 
 

et al., 2010 and Altemini et al., 2017). Several disorders associated with oxidative 

stress can be treated with plant-derived antioxidants with free-radical scavenging 

abilities (Ramchoun et al., 2009). Ascorbic acid, beta carotene, and numerous other 

phenolics have vital roles in lowering inflammation, slowing the aging process, and 

avoiding some malignancies (Duthie et al., 1996; Altemini et al., 2017). Plant extracts 

have been shown in studies to have the ability to scavenge free radicals (Agati et al., 

2012; Mbaebie et al., 2012; Adebayo et al., 2015; Tshikalange et al., 2016; Olaokun 

et al., 2017).  

 

 

 
1.10 Inflammation and diseases 
An organism's physiological response to injury, microbial infections, particulate debris, 

and malignant cancer cells is inflammation. Prolonged inflammation can cause certain 

diseases or exacerbate ones that already exist. Acute inflammation arises from an 

immediate response to the foreign body or microorganism, whereas a delayed, 

prolonged response typically leads to a chronic disease. The major steps in an 

inflammatory reaction are initiation of the reaction, progression and termination. 

Inflammation has been found to further the progression of existing disease conditions. 

Therefore, understanding the role played by inflammation in these diseases is 

significant in designing newer therapeutic strategies and disease management in 

patients (Krishnamoorthy and Honn., 2006).  

 
Acute inflammation occurs quickly and lasts only a short time whereby fluids and 

plasma proteins are released and leukocytes and neutrophils migrate around the 

injured area. The acute inflammatory response aims to destroy bacteria, viruses, and 

parasites while speeding up the healing of wounds (Iwalewa et al., 2007).   

 

When lymphocytes and macrophages are present, chronic inflammation lasts longer 

and manifests in cell tissues, leading to fibrosis and tissue necrosis. Degenerative 

diseases like cancer, congestive heart failure (CHF), rheumatoid arthritis, 

atherosclerosis, heart disease, Alzheimer's, asthma, multiple sclerosis (MS), diabetes, 

infections (bacteria, fungi, parasites), gout, IBD-inflammatory bowel disease, aging, 



24 
 

and other neurodegenerative disorders are brought on by ongoing chronic 

inflammation (Dalgleish and Byrne, 2002; Iwalewa et al., 2007).  

 

 

 
 
Figure 1.6: The 5-lipoxygenase pathway and therapeutic potential of 5-lipoxygenase inhibitors 

in GI cancers (www.researchgate.net, 2021). 

 

 

In a review done by Iwalewa et al (2007), elevated IL-6, ROS and myeloperoxidase in 

chronic infections served as indicators in viral and bacterial infections. These 

processes are responsible for injury to the cells through a number of ways including 

peroxidation of the cell membrane lipids and oxidative damage of proteins or DNA. 

 

These chronic conditions and diseases have been associated with the increased 

expression of pro-inflammatory mediators, which trigger the production of pro-

inflammatory cytokines, NF kappa B, NADPH oxidase, phospholipase A2, COX-1 and 

-2, 5-LOX, myeloperoxidase, and iNOS, as well as an increase in oxygen consumption 

and oxygen-free radical production, can eventually result in certain degenerative 

diseases (Iwalewa et al., 2007).  

http://www.researchgate.net/


25 
 

 

When the neutrophils are stimulated appropriately, they facilitate the splitting of 

arachidonic acid from membrane phospholipids and arachidonic acid metabolism 

takes place via cyclooxygenase (COX) enzyme which is the isoforms, COX-1 and 

COX-2 either through the LOX route, which results in the production of leukotrienes 

and hydroperoxy-eicosatetraenoic acids, and prostaglandins and thromboxane A2 

(Bouriche et al., 2005; Akula & Odhav, 2008; Adebayo et al., 2015). Inhibiting the COX 

enzyme is thought to have played a significant role in the development of anti-

inflammatory and anti-nociceptive medications. (Karim, et al., 2019).  

 

 
1.10.1 Oxidative species as inflammation mediators 
When the inflammatory cells are stimulated, they go through a respiratory burst, and 

ROS such as hydrogen peroxide, superoxide anion and other secondary oxidants are 

released as well as products of the arachidonic acid cascade. A hypothesis that DNA 

damage is induced in tissues during inflammatory reactions was developed and that 

activated neutrophils are responsible for inflammatory diseases (Ward et al., 1994).  

ROS and RNS, such as nitric oxide, (NO) are produced by the enzyme NO synthase 

(NOS) and NADPH oxidase isoform. ROS and RNS have physiological roles and 

occur at low or moderate concentrations, they have positive impacts in the cells in the 

cells such as defense against infectious and cellular signalling pathways but excessive 

stimulation of NADPH or the mitochondrial electron transport chain can lead to 

oxidative stress, which can be harmful to the cell's structural components, including 

proteins, DNA, and lipids in cell membranes (Sari et al., 2017). These 

oxidising substances are produced by neutrophils, monocytes, macrophages, and 

eosinophils, which invade the tissues (Conner and Grisham, 1996). Mitochondria also 

produce ROS (Closa and Folch-puy, 2004).  

Phagocytes are activated when proinflammatory mediators or bacterial products with 

specific receptors on the leucocyte plasma membrane interact, resulting in the 

formation of NADPH oxidase. This enzyme catalyses the production of large amounts 

of the superoxide anion radical (NADPH + O2→  NADP+ O2- ) (Klebanoff, 1992; Conner 

and Grisham, 1996). Superoxide is relatively unreactive toward most biological 

substrates and will reacy very rapidly and spontaneously or by attaching to an enzyme 



26 
 

dismutase to yield hydrogen peroxide (H202) and oxygen (02): O2-+ O2- + 2H+ → H202 

+ O2. Hydroxyl radicals have been shown to peroxidise lipids, oxidize proteins and 

promote DNA strand splitting (Grisham,1992; Conner and Grisham, 1996). The 

reaction of the hydroxyl radical with the DNA base deoxyguanosine results in the 

formation of 8- hydroxydeoxyguanosine which in turn causes an increase in the 

frequency of misincorporation of DNA bases, suggesting that these mutations in the 

cells induced by oxygen radicals could play a part in the induction of autoimmunity 

and, possibly, carcinogenesis (Merry, et al, 1989). 

 

Besides promoting toxicity, reactive oxygen products may also worsen inflammation 

via the upregulation of several different genes involved in the inflammatory response 

which may occur by the activation of certain transcription factors, such as nuclear 

transcription factor-kB (NFkB) (Conner & Grisham, 1996; Closa & Folch-puy, 2004). 

NF kappaB (NFkB) is made up of proteins and it binds to DNA to activate gene 

transcription. The transcription factor NFkB controls the expression of numerous 

proteins involved in inflammation, including all pro-inflammatory cytokines, 

chemokines, and enzymes of the arachidonic acid cascade (Iwalewa et al., 2007).       

Closa and Folch-puy (2004), reported on the beneficial effects of antioxidants such as 

N-acetylcysteine and pyrrolidine dithiocarbamate on their ability to inhibit NFkB 

activation.   

 

 
1.10.2 Lymphoedema and inflammation 
Lymphoedema is a chronic condition marked by the buildup of interstitial fluid in 

tissues as a result of damaged lymphatic vessels, which causes swelling and limb 

dysfunction. Primary or hereditary lymphoedema is caused by intrinsic abnormalities 

of the lymphatic system brought on by gene abnormalities involved in the growth and 

development of the lymphatic vessels. Secondary lymphoedema occurs slowly but 

progressively resulting from injury, infection, and inflammation. Lymphatic vessels of 

people in developed countries can also be disrupted by surgical procedures like 

lymphadenectomy or radiotherapy for cancers such as breast cancer and cancer that 

require lymph node dissection and radiotherapy for melanoma, sarcoma, neck, and 

gynaecological cancers (Ly et al., 2017; Yuan et al., 2019). Secondary lymphoedema 



27 
 

pathological features include inflammation, oedema, dermal fibrosis, the development 

of adipose tissue, and immune system dysfunction, which makes patients more 

susceptible to infections (Zampell et al.,2012; Yaun et al, 2019). Experimental and 

clinical studies have associated inflammation with the pathophysiology of 

lymphedema and rats were used in a study that led to a conclusion to say 

lymphoedema results in a chronic inflammatory reaction  (Ly, et al., 2017). In another 

study, it was found that genetic variations in some sick patients revealed that 

inflammatory genes were associated with more symptoms of lymphoedema (Ly, et al., 

2017). Increased fluid flow serves as an early sign of inflammation that prompts 

surrounding fibroblasts to initiate rapid matrix repair through autocrine upregulation of 

transforming growth factor-1 (TGF-1) and differentiation into myofibroblasts. When 

fluid accumulation in the interstitial space persists, it contributes to an ongoing cycle 

of inflammation that eventually results in symptoms of lymphoedema  (Ly, et al., 2017). 

 
 
 
1.10.3 Medicinal plants as alternatives for inflammatory diseases  
Since several epidemiological studies have shown a link between the consumption of 

fruits and vegetables high in polyphenols like flavonoids and the development of 

chronic diseases like cancer, cardiovascular disease, and inflammation, the search for 

natural remedies and phytochemicals with anti-inflammatory activity has significantly 

increased (Gunathilake et al.,  2018).  Sari and Katrin (2017), reported on the 

properties of the flavonoids baicalein and apigenin as inhibitors of lipoxygenase in 

vitro. The antioxidant properties of alkaloids, phenolics, and triterpenoids have also 

been shown to have anti-inflammatory effects by decreasing the production of O2- and 

malondialdehyde (MDA), plasma extravasations, and leukocyte cell migration during 

radical damage. Lastly, they increase the likelihood of superoxide dismutase (SOD) 

activity in radical scavenging activity (Nardi et al., 2007). Numerous chemicals having 

antioxidant capabilities that can combat radical species in vivo, including fatty acids, 

terpenes, phytosterols, esters, and alcohols, have also been discovered to be present 

in plants (Oso and Karigidi, 2019).   Using herbal drugs with less toxicity and adverse 

effects from the use of allopathic medications have increased the popularity of certain 

medications, which has contributed significantly to the development of potential 



28 
 

pharmaceuticals. Additionally, more than 1.5 million practitioners now practice 

traditional medicine, making it more widely used (Ondua et al., 2016). 

 

 

1.10.4 Non-steroidal anti-inflammatory drugs (NSAIDs) 
The most popular medications used to treat inflammatory and pain diseases are non-

steroidal anti-inflammatory medicines (NSAIDs). This comprises the medication 

families that contain ibuprofen, celecoxib, rofecoxib, meloxicam, indomethacin, and 

diclofenac (Ong et al., 2007; Karim et al., 2019). NSAIDs' pharmacological effect 

involves blocking the enzyme cyclooxygenase, which prevents prostaglandin 

formation (Karim et al., 2019). Without altering the activity of the 5-LOX enzyme, the 

selective inhibitors prevent prostaglandin production (Mogana, et al., 2013). However, 

it has been observed that these medications have a number of undesirable side 

effects, including stomach inflammation that causes gastric ulcers (Gunathilake et al., 

2018). The detrimental effects on the cardiovascular system are caused by COX-2 

enzyme inhibition, while the gastrointestinal side effects of long-term NSAID use are 

caused by COX-1 inhibition (Sostress et al., 2010; Karim et al., 2019). Long-term 

NSAID use has been linked to the development of gastric ulcers because these drugs 

have large levels of LTB4 in their walls, which draw leukocytes to the stomach and 

may hasten the development of ulcers. Recently, compounds known as "double 

inhibitors," which inhibit not only COX-1 and COX-2 but also 5-LOX, have been 

reported. They have antioxidant properties that may be useful for managing the 

metabolic processes that cause inflammatory conditions and can lessen adverse 

effects on the stomach and cardiovascular system by balancing the body's arachidonic 

acid metabolism. (Mogana, et al., 2013).  

 

Celecoxib is the only coxib that is currently approved by the US Food and Drug 

Administration (FDA) as it has less COX-2 selectivity than other medications in the 

same class and has some COX-1 inhibitory effects. Rofecoxib and valdecoxib are two 

selective inhibitors that were taken off the market because they had relatively high 

specificity for the COX-2 enzyme and subsequent cardiovascular adverse effects (Sun 

et al., 2007; Karim et al., 2019).  

 
 



29 
 

 
1.11 Problem Statement 
Elephantiasis is a disease that affects many countries, including South Africa. 

According to a report by Dlamini and eNCA (2013), patients have been turned away 

from several public hospitals in South Africa because there is no therapy available 

there or because the illness requires a specialist. The patients can, therefore only lie 

on their beds watching their legs getting bigger and becoming more and more inactive. 

Cox (2012) reported that people suffering from elephantiasis are usually bedridden 

and confined to bleak and dingy surroundings in rundown houses, and they are 

struggling to get treatment. The patients experience not only physical infirmity but also 

mental, social, and financial losses that exacerbate poverty and shame. 
 

All of this accounts for the need to give the disease special research that will focus on 

treatment strategies available in South Africa on how to manage the disease and an 

assessment of reported cases, especially those people that have been affected been 

severe lymphoedema.  

 

In collaboration with Dr. Dirk le Roux and his team of physiotherapists, the Netcare 

Foundation has assisted in the treatment of some of the disease-stricken patients at 

Netcare Sunninghill Hospital. A few of the severely disabled patients have received 

therapy with the help of money from the Netcare Foundation, but because treatment 

takes so long, only a select few patients are eligible because of the program's stringent 

admission requirements. The patients are typically immobile and severely disabled, 

with little future prospects unless they can receive therapy. (Netcare Limited, 2013).  

 

There is a tremendous need for coordinated and accessible programs that will help