ALPHA-GLUCOSIDASE ACCOMPANYING EXTRACELLULAR AMYLOLYTIC ENZYMES OF SACCHAROMYCOPSIS-FIBULIGERA

An alpha-glucosidase was isolated from the culture medium of the dimorphic yeast Saccharomycopsis fibuligera where it accompanied the amylolytic enzymes alpha-amylase and glucoamylase. The physicochemical properties of the enzyme purified to apparent homogeneity by column chromatography on Superose 6 and Mono Q were: pH optimum 4.6-5.8, temperature optimum 40-degrees-C and relative molecular mass 250 000. The alpha-glucosidase had highest activity on maltose [100] with relative rates of activity on maltotriose, maltotetraose and maltopentaose of 50, 48 and 42, respectively. Starch was hydrolyzed very slowly at about 3 % of the rate obtained for maltose. Sucrose, phenyl- and methyl-alpha-D-glucopyranoside were resistant to hydrolysis.