酶解辅助提取山药多糖的研究

ENZYMOLYSIS-ASSISTED EXTRACTION OF POLYSACCHARIDES IN CHINESE YAM

采用α-淀粉酶、糖化酶辅助提取山药多糖,通过试验优化酶解辅助提取工艺,并从产物得率、纯度两方面将该工艺与温水浸提工艺进行对比.试验中分别对α-淀粉酶、糖化酶各自的添加量和酶解时间4个单因素进行优化,根据粗多糖含量、粗多糖纯度以及淀粉的定性检测结果,判断得出各单因素的最优条件,并对比温水浸提工艺.结果表明,经过优化后的酶解辅助提取工艺,山药多糖的得率为温水浸提的3.5倍左右,纯度比温水浸提的提高1倍左右,既避免了大量淀粉混入所引起的多糖值虚高,又破除了淀粉颗粒对多糖的包裹阻碍,使山药多糖得率得到了有效提高.

Polysaccharides are believed to be one of the active ingredients in the Chinese yam. The main extraction method of polysaccharides from yam is the water extraction at the present time, however, the yield and purity are not high because of the limitations of water temperature and starch interference. The present study was to use the a -amylase and saccharifying enzyme to optimize the extraction of polysaccharides from Chinese yam. The dosage and the enzymatic hydrolysis time of the two enzymes were optimized by detecting the extraction yield and purity of polysaccharides. Result showed that the extraction with 0.16% a -amylase and 0.12% saccharifying enzyme for 60 min could improve the yield and purity of yam polysaccharides by 3.5 and 1 times, respectively, compared with the normal immersing extraction. The starch granules structurally present together with polysaccharides and may interfere the extraction process. The multi-level structure of the yam polysaccharides may be crossed with the starch granules in the space, which may form a package of yam polysaccharide. Through the enzymolysis of the amylase and saccharifying enzyme, starch granules dissolution was promoted and the starch mixed in the extraction solution was also removed effectively. The present enzymolysis-assitant method could avoid the false high extraction yield and assist the extraction by helping polysaccharides extricate from starch granules.