Ondersoekinge oor die afbraak van aromatiese verbindings deur mikro-organismes

Loading...
Thumbnail Image
Date
1960-01
Authors
Scott, De B.
Journal Title
Journal ISSN
Volume Title
Publisher
University of the Free State
Abstract
English: 1. In a survey of the relevant literature the methods of investigation, the systematic and biochemical aspects and the significance of microbial degradation of aromatic compounds has been discussed. 2. In a preliminary investigation it was found that nonselectivily isolated strains of streptomycetes dit not grow on a mineral salt medium with a simple aromatic compound as sole source of carbon. 3. Bacteria, fungi and one Nocardia strain able to use aromatic compounds as sole source of carbon and energy, were isolated from enrichment cultures. 4. From turbidimetric growth measurements it was found that optimum cell development of the bacteria and actinomycete investigated in a medium with a low concentration of aromatic substrate in most cases took place within two days. 5. The oxidation of a number of aromatic compounds by the bacteria and actinomycete isolated, was studied with the aid of the direct method of Warburg. 6. The method used for the calibration of manometers and Warburg flasks is described. 7. The technique of sequential induction was applied to determine the pathway of microbial degradation of the aromatic compounds investigated. With this technique the following hitherto unpublished reactions of bacteria have been found: (i) Salicylic acid - gentisic acid. (ii) Saligenin - salicylic aldehyde - salicylic acid - catechol and gentisic acid. (iii) Syringic acid - gallic acid. (iv) Guaiacol - catechol. (v) Vanillin - vanillic acid - protocatechuic acid. (vi) Veratric aldehyde - veratric acid - vanillic acid - protocatechuic acid. The degradation of phenol, benzoic acid, mandelic acid, p-cresol, m-hydroxybenzoic acid and anisic acid by bacteria, and of toluene by Nocardia sp., as studied with manometrical methods, was found to be identical with the pathway already described for bacteria and fungi. The degradation pathway of o- and m-cresol could not be established with certainty with the method used.
Afrikaans: 1. In die literatuuroorsig is die ondersoekingsmetodes, die sistematiese en biochemiese aspekte en die betekenis van die mikrobiale afbraak van aromatiese verbindings bespreek. 2. In 'n voorlopige ondersoek is vasgestel dat 'n aantal nieselektief geïsoleerde streptomyceet-stamme nie op 'n minerale voedingsmedium met 'n eenvoudige aromatiese verbinding as enigste koolstofbron groei nie. 3. Bakterie, fungi en 'n Nocardia-soort wat aromatiese verbindings as enigste koolstof- en energiebron gebruik, is uit ophopingskulture geïsoleere 4. Het turbidimetriese groeibepalings is vasgestel dat die optimale selontwikkeling van die ondersogte bakterieë en aktinomyceet in 'n medium met 'n lae konsentrasie aromatiese koolstofbron in die meeste gevalle binne twee dae plaasgevind het. 5. Met behulp van die direkte metode van Warburg is die oksidasie van 'n aantal aromatiese verbindings deur die geïsoleerde bakterie- en aktinomyceet-starame bestudeer. 6. Die metode gebruik vir die yking van die manometers en manometerflessies is beskryf. 7. Die opeenvolgende induksietegniek is toegepas om die mikrobiale afbraakpad van die ondersogte aromatiese verbindings vas te stel, Met hierdie tegniek is die volgende onbeskrewe reaksies vir bakterieë vasgestel. (i) Salisielsuur - 2,5-dihidroksibensoësuur. (ii) Saligenien - salisielaldehied - salisielsuur - katechol en 2,5-dihidroksibensoënsuur. (iii) Syringasuur - gallussuur. (iv) Guaiakol - katechol. (v) Vanillien - vanilliensuur - 3,4-dihidroksibensoësuur. (vi) Veratrumaldehied - veratrumsuur - vanilliensuur - 3,4- dihidroksibensoësuur. Die afbraakpad van fenol, bensoëlsuur, amandelsuur, p-kresol, m-hidroksibensoësuur en anyssuur deur bakterieë en van tolueen deur Nocardia sp. soos manometries vasgestel, was in ooreenstemming met dié wat reeds uit die literatuur bekend was vir fungi en bakterieëo Die afbraak van o- en m-kresol kon met die gebruikte metode nie met sekerheid vasgestel word nie.
Description
Keywords
Dissertation (M.Sc. (Microbiology))--University of the Free State, 1960, Aromatic compounds
Citation