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研究了微生物Aspergillus oryzaec42菌株产特异的柴胡皂苷糖苷酶的分离纯化及其酶学性质.结果表明,该酶能够水解柴胡皂苷A或柴胡皂苷B2侧链的3-O-β-(1→3)-Glc和3-O-β-Fuc,其分子量约为58000.柴胡皂苷糖苷酶首先水解柴胡皂苷A或B2侧链的3-O-β-(1→3)-Glc生成3-O-β-Fuc-柴胡皂苷元A或B2,然后进一步水解3-O-β-Fuc-柴胡皂苷元A或B2的3-O-β-Fuc生成柴胡皂苷元A或B2.柴胡皂苷糖苷酶的最适反应温度为4℃,最适pH值为5.0;Na+和K+对酶活力的影响不明显;Cu2+,Hg2+和Ag+对酶活力有显著的抑制作用;Ca2+和Mg2+对酶活力有轻微的激活作用.
The isolation, purification and enzymatic properties of the saikosaponins from Aspergillus oryzaec42 were studied.The results showed that the enzyme could hydrolyze 3-O-β- (1 → 3) -Glc and 3-O-β-Fuc with a molecular weight of about 58000. Saikosaponin glucosidase first hydrolyzes 3-O-β- (1 → 3) -Glc in the side chains of saikosaponin A or B2 3-O-β-Fuc-Saikosaponin A or B2 and then further hydrolyzing 3-O-β-Fuc of safranin A or B2 of 3-O-β- The optimal reaction temperature of saikosaponin glycosidase was 4 ℃, and the optimum pH value was 5.0. The effect of Na + and K + on enzyme activity was insignificant. Cu2 +, Hg2 + and Ag + significantly inhibited the activity of Ca2 +, Mg2 + Slight activation of enzyme activity.