Inhibition of β-Fructofuranosidases and α-Glucosidases by Synthetic Thio-fructofuranoside

A synthetic β-thio-fructofuranoside of mercaptoethanol inhibited not only β-fructofuranosidases but also α-glucosidases. The compound was hardly hydrolyzed by the glycosidases. The thio-fructoside competitively inhibited β-fructofuranosidases from Aspergillus niger, Candida sp., and Saccharomyces cerevisiae, but not Arthrobacter β-fructofuranosidase at all. Sucrase activity of rat intestinal sucrase/isomaltase complex was also suppressed in the presence of the thio-fructoside. The thio-fructoside showed noncompetitive inhibition toward maltase activity of the rat intestinal enzyme complex and Saccharomyces sp. α-glucosidase. Inhibition against the Bacillus stearothermophilus α-glucosidase, Rhizopus glucoamylase, and porcine kidney trehalase were more slight than that against these two α-glucosidases.