生物转化法合成葡萄糖基抗坏血酸的产酶菌株筛选及发酵条件优化

Screening of α-glucosidase-producing Strain and Optimization of Its Fermentation Conditions to Produce Glucopyranosyl-L-ascorbic Acid by Biotransformation

从土壤中筛选到1株产α-葡萄糖苷酶(EC 3.2.1.20,α-glucosidase)的菌株WPD2,通过对其进行形态学和18S rDNA序列分析及系统发育研究,该菌株初步鉴定为黑曲霉(Aspergillus nigerEU366904),该菌经产酶、转化反应后葡萄糖基抗坏血酸产量达到370 mg/L左右。摇瓶实验确定了优化后的产酶条件为:培养温度34℃,培养时间60 h,以110 g/L的麦芽糖为碳源、10 g/L的(NH4)2SO4为氮源,优化后葡萄糖基抗坏血酸产量达到410 mg/L左右。

An α-glucosidase-producing strain WPD2 was isolated from the soil, and was identified as As- pergillus niger based on morphology and phylogenetic analysis of 18S rDNA sequence. The content of ascorbic acid glucoside came to 370mg/L after biotransformation. The conditions for enzyme formation of strain WPD2 following the optimization phase were maltose 110g/L , ammonium sulphate 10g/L, culture time 60h,temperature 34℃ and the content of ascorbic acid glucoside reached 410mg/L.