ANAEROBIC DECOMPOSITION OF ORGANIC MATTER BY THE MICROFLORA OF POLLUTED RIVER WATERS : III. THE FORMATION OF FATTY ACIDS FROM AMINO ACIDS, PROTEINS AND SEVERAL OTHER COMPOUNDS

Abstract

TEZUKA, Yasuhiko (Tokyo Metropoli. Univ., Tokyo) Anaerobic decomposition of organic matter by the microflora of polluted river-waters. III. The formation of fatty acids from amino acids, proteins and several other compounds. Jap. J. Ecol. 14. 91 -97 (1964). Anaerobic degradation of amino acids, proteins and several other compounds were investigated on media enriched with a single organic substrate or mixed substrates and inoculated with the microflora of the polluted water of the Sumida River, Tokyo. Of ten amino acids tested, which were added individually to the basal medium, glycine, β-alanine, L-proline, L-valine and L-phenylalanine were difficult to be attacked during the incubation time of five days at 35℃. On the other hand, L-cysteine, L-aspartate, L-glutamate, L-lysine and L-serine were metabolized almost completely under the same incubation conditions, and 43 to 75 per cent of the carbon added as substrates was recovered into that of the volatile fatty acids, of which acetate was predominant. In the case of these amino acids, except L-cysteine, the production of volatile fatty acids was coupled with sulfate reduction. L-cysteine gave rise to sulfide and acetate, though it was not utilized directly or indirectly as the substrate for sulfate reduction. Peptone, sodium caseinate, glycerol and citrate were all fermented with the formation of volatile fatty acids accompanied with sulfate reduction. Degradation of succinate, in which the formation of fatty acids and sulfate reduction were also recognized, was unique in that propionate was produced predominantly as the result of decarboxylation. Palmitate was metabolized slightly. Judging from their fermentation balance, glucose and peptone, being added to the mixture at various concentration ratios, seemed to be decomposed independently of each other.