Detection of Hippurate Hydrolase among Bacillus Species by Thin Layer Chromatography and other Methods

S ummary . The ability of 111 isolates of 33 species of Bacillus to hydrolyze hippurate into benzoic acid and glycine was tested. All, other than the strains classified as B. badius, B. cereus var. mycoides, B. cereus var. thuringiensis, B. macquariensis, B. medusa, B. pacificus, B. psychrosaccharolyticus and some B. macerans and B. polymyxa strains, were positive by thin layer chromatography (TLC). Of the 4 methods compared (hippurate agar, the sulphuric acid method, precipitation with ferric chloride and TLC), only the TLC procedure allowed a rapid and definite detection of the hydrolytic product, benzoic acid. The use of hippurate hydrolase as an additional diagnostic aid in the differentiation of aerobic spore-forming bacilli is discussed. Other characters were used to compare some recently described Bacillus spp. The combination B. cereus subsp. medusa n. subsp. is proposed.