PRODUCTION OF BETA-APIOSIDASE BY ASPERGILLUS-NIGER - PARTIAL-PURIFICATION, PROPERTIES, AND EFFECT ON TERPENYL APIOSYLGLUCOSIDES FROM GRAPE

Various aspects of fungus-originated beta-apiosidase were studied. The production of the enzyme on various carbon sources by fungi appeared to be inducible as it was only produced when apiin, an apiosylglucsoide, was present in the culture medium. The influence of apiin concentration, nitrogen source, and surfactants on enzyme production was studied. The enzyme was partially purified by filtration chromatography on Ultrogel AcA44 and ion-exchange chromatography on DEAE-Sepharose CL6B. The molecular weight of this enzyme was 38 000; K(m) and V(max) values for p-nitrophenyl beta-D-apiofuranoside were, respectively, 16 mM and 0.192 nkat/mg of protein. With regard to activity, the optimum pH and temperature were, respectively, 5.6 and 50-degrees-C. The optimum pH of stability was 7. Na+, Mg2+, Mn2+, Cu+, CU2+ have an inhibitor effect on beta-apiosidase activity. Conversely, the enzyme was inhibited neither by glucose nor by ethanol. The effect of beta-apiosidase toward apiosylglucosides of terpenols, grape flavor precursors, was tested.