酶法测定黄芪含片中黄芪多糖的研究

Determination of Astragalus Polysaccharide of Astragalus Tablet by Enzyme Method

建立排除黄芪片剂中辅料干扰多糖含量测定的方法。采用苯酚-硫酸比色法测定黄芪多糖含量,糖化酶水解麦芽糊精,80%乙醇溶液进行醇沉分离,考察反应温度、p H、酶与底物比例及反应时间对酶解反应的影响,验证糖化酶能否水解黄芪多糖。反应温度58℃、p H4.5、酶与底物比例1∶5、反应时间28 min时麦芽糊精完全水解,80%醇沉后在490 nm处测定无明显吸收。采用酶解法可以准确测定黄芪片剂中多糖的含量,测定结果与加入量无差异(P>0.05)。糖化酶水解麦芽糊精,不水解黄芪多糖,对黄芪多糖含量的测定不存在干扰,可用于片剂中多糖含量测定。

To develop a method for excludeing the interfere of adjuvant on determination of polysaccharide in tablets. A phenol sulfuric acid method was used to determine the content of polysaccharide. Maltodextrin was hydrolyzed with saccharifying enzyme, precipitatede with 80 % ethanol. The effects of temperature, p H,enzyme dosage and reaction time on the hydrolysis were investigated. Morever, the hydrolysis effect of saccharifying enzyme on Astragalus polysaccharide was inspected. Results showed that saccharifying enzyme could fully hydrolyze maltodextrin at the condition of ： temperature of 58 ℃, p H4.5, enzyme to substrate ratio was 1 ∶ 5, reaction time 28 min, as well as not hydrolyze Astragalus polysaccharides. The saccharifying enzyme could excluded the interference of maltodextrin on determination of polysaccharide, the method was simple,accurate, reproducible, and could be used for determination of Astragalus polysaccharides in buccal tablets.