生物法合成AA-2G的菌种产酶条件及转化方法研究

采用生物转化的方法,以L-抗坏血酸和糖基供体为底物,采用保藏菌种反硝化利斯特氏菌SHⅢA为环麦芽糊精聚糖糖基转移酶产酶菌种,并设计实验,以期对生产AA-2G的各影响因素进行考察.研究结果表明:菌种的最佳产酶条件为:麦芽糖为碳源,蛋白胨作为氮源,金属离子为Cu2+,pH值为10,培养温度为35℃,接种量为10%.AA-2G的最佳合成条件为:以质量分数为33%的β-环糊精作为糖基供体,以质量分数为22%的L-抗坏血酸作为底物,温度20℃下反应30 h,AA-2G产量可达8.60 g/L.

Studys on Production Conditions of CGTase and Biotransformation of AA-2G

L-ascorbic acid and donors of glycosyl were employed in this article to study synthesis of 2-0-glucopyranosyl-L-ascorbic acid（AA-2G）.Strain of SHⅢA was using for producing cyclodextringlu canotransferase（CGTase）.Results shows that the best condition for CGTase production is using maltose as carbon source,peptone as nitrogen source and Cu2＋ as metal ion,pH 10,reacting under 35 ℃ with 10 % inoculum.The best condition of AA-2G compound is that using 33 % β-cyclodextrin as donor of glycosyl and 22 % L-ascorbic acid as substrate,reacting under 20 ℃ for 30 hours,and the output of AA-2G could reach 8.60 g/L.