Isolation of Clostridium bifermentans from oil mill wastewaters convertingcinnamic 3-phenylpropionic acid and emendation of acid to the species

A strictly anaerobic, Gram-positive, motile and spore-forming bacterium, de signated strain TYR6, was isolated from olive mill wastewaters on cinnamic acid. Cells were straight rods and occurred singly, in pairs or in short ch ains. Strain TYR6 utilized a number of carbohydrates (glucose, fructose, ma nnose, maltose, sorbitol, myo-inositol, and ribose) and peptides (yeast ext ract, Casamino acids, Biotrypcase, peptone, and gelatin), grew optimally at 37 degreesC and at pH7, and had a G + C content of 29.1 mol%. Strain TYR6 was phylogenetically related to Clostridium bifermentans (similarity of 99% ) with which it bears a high phenotypic similarity and DNA homology (80%). In addition, strain TYR6 shares with C. bifermentans ATCC 638(T) and DSM 63 0 the ability to metabolize cinnamic acid (but not any of its derivatives), with or without glucose supplementation, via the reduction of the double b ond of the C-3-aliphatic side chain to 3-phenylpropionic (hydrocinnamic) ac id. Addition of glucose accelerated the rate of growth and increased marked ly the conversion yield of cinnamic acid to 3-phenylpropionic acid. Based o n the results, we propose to emend the description of C. bifermentans. (C) 2001 Academic Press.