MICROBIAL DECOMPOSITION OF PECTIC SUBSTANCES 1. Role of Soil Streptomycetes in the Process

Abstract

One hundred and fifty streptomycete cultures, representing several species, were screened for their pectolytic activity of these as many as one hundred and forty-five were observed to be pectolytic i.e. possessing the ability to bring about either demethylation, glycosidic hydrolysis or both types of breakdown of the pectin molecule. That demethylation was enzymatic was confirmed by testing for pectin methyl esterase activity by Kertesz's method in the case of a few species. The favourable effect of calcium carbonate in the test medium on the growth and rate of decomposition of pectin as determined by the calcium pectate method was also shown. The pectin glycosidase elabora ted by a strain of S. viridochromogenes was obtained as an acetone powder. This enzyme was shown to be active at pH 7.6but not at pH 4.5.