3,5-二硝基水杨酸法测定灵芝多糖的含量

目的 建立3,5-二硝基水杨酸法（简称DNS法）测定灵芝多糖的含量.方法 在氢氧化钠和丙三醇的存在下,还原糖能将3,5-二硝基水杨酸（DNS）中的硝基还原成氨基,生成氨基化合物,此化合物在过量的氢氧化钠碱性溶液中呈橘红色,在一定波长下具有最大吸收,吸光度与还原糖含量有线性关系.因此可利用吸光度测定多糖含量.结果 半乳糖浓度在0.15～0.41mg/ml范围内,与吸收度值呈良好的线性关系,灵芝总糖供试液和单糖供试液平均回收率分别为97.3％和99.4％,精密度、回收率RSD％均小于3％.结论 DNS法测定灵芝多糖的含量结果准确、可靠,重现性好.

Determination of ganoderma lucidum polysaccharide content by 3,5-dinitrosalicylic acid method

Objective To establish a 3,5 - dinitrosalicylic acid method （ DNS method） for determining the content of ganoderma lucidum polysaccharides. Methods Under the existence of sodium hydroxide and glycerol,reducing sugar could reduce the nitryl in 3,5 -dinitrosalicylic acid （DNS） to azyl,and generate amino -compounds. This compound would be orange red in the liquid of ex- ceed sodium hydroxide, had the maximum absorption under some special wavelength, and its absorbance had a linear relation with the amount of reducing sugar. Thus, the content of polysaccharides could be detected by absorbance. Results The galactose concentra- tion in the range of O. 15 -0. 41mg/ml had better linear relation with absorbance value~ The average recovery rates of total and single sugars in lucid ganoderma were 97.3 % and 99.4% , respectively, and their precision and accuracy RSD% were all less than 3% ~ Conclusion DNS method is an accurate and reliable method to detect the content of ganoderma lucidum polysaccharides, with good reproducibility.