黑曲霉B0201生料发酵产单宁酶的提取及酶学性质研究

对黑曲霉B0201利用五倍子为诱导物生料发酵产胞外单宁酶的提取及酶学性质进行了研究.结果表明:硫酸铵两步沉淀的饱和度为40%和90%;该酶的最适温度为40℃,最适pH为5.0,低于60%时的热稳定性高,60℃以上迅速失活.Zn~(2+)、Mg~(2+)、吐温80、EDTA等对酶活力无明显影响,Fe~(3+)、Cu~(2+)、Fe~(2+)、Ba~(2+)、Mn~(2+)、Ca~(2+)、Al~(3+)等对酶有抑制作用.以没食子酸丙酯(PG)为底物,单宁酶的米氏常数Km为0.514mmol/L,Vmax为71.8μmol/L·min.

Study on extraction and enzymatic properties of tannase produced by Aspergillus niger B0201 under uncooked material fermentation

The extraction and enzymatic properties of extracellular tannase produced by Aspergillus niger B0201 under uncooked material fermentation was studied. The concentration of ammonium sulphate for enzyme precipitation was 40% and 90%.The optimum temperature of tannase activities was 40℃ and the optimum pH was 5.0.Tannase was stable under 60℃ and it would be rapidly inactivated if the temperature went above 60℃.The effect of ZR2~(2+) , Mg~(2+) , Tween80 and EDTA weren' t notable. Fe~(3+) , Cu~(2+) , Fe~(2+) , Ba~(2+), Mn~(2+), Ca~(2+)and Al~(3+) inhibited tannase activity. By using the PG as the substrate, the Km and Vmax of tannase were 0.514mmol/L and 71.8μmol/L· min.