目的:通过建立测定龙胆中多糖含量的方法,考察贵阳乌当水田、龙里洗马河不同采收期龙胆根中多糖含量的变化,为确定龙胆药材最佳采收期提供依据。方法:采用硫酸—苯酚法显色后用分光光度计测定吸收度,测定波长为491nm,通过计算测出龙胆根中多糖的含量。结果:龙胆根中多糖浓度在2.11~14.08μg/ml范围内呈现良好的线性关系,回收率平均值=99.58%,RSD=1.26%。两产地龙胆根中多糖的含量均以10月份最高。结论:方法简便,准确,重复性好。 OBJECTIVE: To establish a method for determination of polysaccharide in Gentiana scabra by investigating the changes of polysaccharide content in Gentiana macrophylla roots collected from Wudang paddy field and Longliema river in Guiyang for the purpose of determining the optimal harvest time. Methods: The absorbance was determined by spectrophotometer with sulfuric acid - phenol method. The measured wavelength was 491 nm. The content of polysaccharides in gentian roots was calculated. Results: The polysaccharide concentration of gentian roots showed a good linear relationship in the range of 2.11-14.08 μg / ml. The average recovery was 99.58% and RSD was 1.26%. Two gentian root polysaccharide content in October were the highest. Conclusion: The method is simple, accurate and reproducible.