壳聚糖固定化木瓜蛋白酶提取牛蒡多糖的研究

以壳聚糖为载体、戊二醛为交联剂固定化木瓜蛋白酶,从牛蒡中提取多糖,考察固定化工艺的选择、固定化酶提取牛蒡多糖的优化条件及固定化酶的稳定性。结果表明:壳聚糖固定化木瓜蛋白酶的最佳条件为:壳聚糖浓度2.5%,加酶量0.3g/g载体,时间6h,温度15℃,pH7.5,酶活力回收率38.98%。提取牛蒡多糖的最佳条件为:固液比1:20,pH6.5,温度60℃,时间8h,加酶量1.8g/g载体,多糖提取率11.04%。固定化酶重复使用五次,酶活力仍保持50%以上。

Study on Extraction of Burdock Polysaccharide Using Immobilized Papain by Chitosan

Chitosan was used as carrier and glutaraldehyde was used as cross-linking agent for the immobilization of papain.The immobilized conditions and stability of immobilized papain as well as its application in extraction of burdock polysaccha-ride were studied.The results showed that optimal conditions of immobilization of papain were 2.5% chitosan concentrations,0.3 g papain/g carrier,6 h times,15 ℃ temperature,pH7.5.The recovery activity of immobilized papain was 38.98%.The optimal conditions of extraction of burdock polysaccharide were 1:20 ratios of solid to liquid(W/V),pH6.5,60 ℃temperature,8h hydrolyzed times,added 1.8g immobilized papain/g carrier.The extracting ratio of burdock polysaccharide was 11.04%.The activity of immobilized papain remained more than 50% after repeated 5 times.