Anaerobic biodegradation of crotonic acid by a bacterial population specialized in the degradation of butyric acid.
Biodégradation anaérobie de l'acide crotonique par une biomasse bactérienne spécialisée dans la dégradation de l'acide butyrique.
Résumé
Volatile Fatty Acids (MFAs) are Intermediate metabolites formed in the process of anaerobic biodegradation of organic matter. They are commonly found in sewage, municipal sanitary landfill leachates and effluents from agricultural and food-processing industries. A good knowledge of the microorganisms involved in VFA biodegradation is necessary to operate the bioreactors. The objective of the present study was to better understand the metabolism of the anaerobic bacteria responsible for the degradation of butyric acid and one its metabolites, crotonic acid. Syntophomonas voltei is one of the butyrate-degrading acetogenic bacteria that has been documented. First studies have shown that this microorganism was not capable of degrading crotonic acid (MCINERNEY et al., 1979. 1981). This is surprising since crotony1-Coenzyme A, in its activated form, is an intermediate metabolite of a-butyrate 8-oxldatlon, which Is the most common mechanism of butyrate biodegradation. In addition, -oxidation of crotoanate is thermodynamically possible, even under standard conditions. These observations are at the origin of the present study, which Investigates the anaerobic biodegradation of crotonate. outer Investigators have followed a similar approach and Isolated S. In pure culture on crotonate. The degradation of crotonate vas studied la a bench-scale up-flow anaerobic filter of 10 Liters, operated in the dark at 35 'C. A first set of experiments was carried out with a biomass exclusively adapted to the biodegradation of butyrate. Heat-expanded vermiculite was as a packing medium. Various experimental protocols were successively followed.
Origine : Fichiers produits par l'(les) auteur(s)
Loading...