[Beta-glycosidase system of sunflowers. Isolation of enzyme and study of their substrate specificity].

: The beta-glucosidase, beta-galactosidase, beta-xylosidase and alpha-L-arabinosidase activities of a partially purified preparation from sunflower seeds were studied by chromatography, polyacrylamide gel electrophoresis and isoelectrofocusing. beta-Glucosidase was isolated as two fractions with high molecular weights. One form of beta-glucosidase does not possess strict specificity to stereochemistry of hexosides C-4 and C-6 and pentosides C-5, whereas the second form exhibits a narrow specificity for C-4 and is low specific towards substituents of C-5. The sunflower seeds also contain acid beta-galactosidase, which possesses a narrow specificity and is not coupled with the beta-glucosidase activity. The molecular weight of beta-galactosidase is 62000.