两步法制备大豆异黄酮操作单元研究

Study on Combined Operations of Soybean Isoflavones with Two Steps Method

麸皮、玉米粉等成分,按1:1加矿泉水,灭菌后接种3%菌种,30℃发酵5d,用缓冲液提取β-葡糖糖苷酶。常用氮源和2.5%乳酸对菌种产酶无影响。纯化的β-葡糖糖苷酶最适pH为4.4～4.8,最适催化温度60℃,最适催化时间30min。用含2%CaCO3的60%乙醇在50℃提取豆粕中苷类物质,用石油醚、氯仿去除杂后,再用正丁醇精提豆粕中苷类。用特制硅胶柱分离正丁醇液,用丙酮等洗脱获高纯度大豆异黄酮糖苷。用β-葡糖糖苷酶水解异黄酮糖苷,经超滤、固定化细胞等处理,制备高纯度大豆异黄酮甙元。

Wheat bran, maze flour and water（l： 1）were mixed into the solid medium, and then sterilized （121 ℃,30min）. The solid medium was inoculated in 3% WD201 strain, fermented at 30℃ for 5days, while β-glucosidase in the fermented medium was extracted with buffer liquid. The common nitrogen elements and 2.5% lactate had no effect on metabolism of WD201 strain which secreted β-glucosidase. The purified β -glucosidase showed the optimum catalysis conditions were： 30℃ and pH4.4- 4.8 for 30min. The soybean isoflavone glucoside in soybean bran was extracted with 60% alcohol contained 2% CaCO3 at 50℃ then the interferential constitutents were extracted with petroleum ether and chloroform, and the isoflaovne glucoside in water phase were extracted with butanol. The isoflavone glucoside in butanol in special silica gel column were eluated again with acetone The isoflavone glucoside was hydrolyed into pure isoflavones with β -glucosidase at the optimum enzyme conditions, and protein and glucose were extracted through superfilter and processed by immobilized cell fermentation.