BETA-GLYCOSIDASE AS A SIDE ACTIVITY IN COMMERCIAL PECTINASE PREPARATIONS OF FUNGAL ORIGIN - THE HYDROLYSIS OF CYANOGENIC GLYCOSIDES

摘要

The enzymatic activities of beta-glycosidase, polygalacturonase, pectin lyase, pectin esterase and reduction in viscosity of pectin solutions were determined in a number of commercial pectinases. The cyanogenic glycosides, amygdalin, prunasin, linamarin, gynocardin, and lucumin, and p-nitro-phenyl-beta-D-glucopyranoside (PNPG) were used as substrates for the beta-glycosidase(s). For all preparations, the glycosidase activities ranged as follows: prunase > amygdalase > linamarase. All preparations had low activity on lucumin. The activities on linamarin and gynocardin were of the the same order of magnitude, about 15 to 25 times lower than that for prunasin. No relationship was found between the levels of pectinolytic activities and the levels of beta-glycosidases. The present knowledge concerning microbial beta-glycosidases with activity on cyanogenic glycosides is briefly discussed.