蒽酮-硫酸比色法测定三叶虫茶中总糖的含量

Determination of total sugars in Sanyechong tea with anthrone-sulfuric colorimetric method

目的测定三叶虫茶的水提液和丙酮提取物中的总糖含量。方法采用蒽酮-硫酸比色法,以供试品空白为参比、葡萄糖为观测指标进行测定。结果在620 nm波长下,葡萄糖对照品在7.0～42μg/mL范围内,吸光度与浓度的线性关系良好,用水和80%乙醇配制对照品时,其回归直线方程分别为Y=0.027 6X-0.047(r=0.998,n=6)和Y=0.037 9X+0.024(r=0.996,n=6);三叶虫茶水溶性总糖含量为9.51%(总固体中总糖含量为30.6%),平均回收率为98.4%,RSD=1.5%(n=6),丙酮总固体中总糖的含量为13.4%,平均回收率97.9%,RSD=1.2%(n=6)。结论此法利用差示光谱法(ΔA法)消除了试样基体有色的干扰,使显色后的吸收峰明显改善,结果可靠,重复性好;也为非水提样品提供了一种可行的总糖含量测定方法,且灵敏度更高。

Objective To determine the total sugars in water extract and acetone extract from Sanyechong tea.Methods The sample was taken as blank fiduciary object and the glucose as index,the total sugars were determined with the anthrone-sulfuric colorimetry.Results The concentration of glucose showed a good linearity with absorbance in the range of 7.0～42 g/mL under 620 nm.The linear regression equation are Y =0.0276X-0.047（r =0.998,n =6） and Y = 0.0379X＋0.024（r=0.996,n=6） by different solvents-water and 80% ethanol respectively;the water-soluble total sugars of Sanye insect tea was 9.52% and the average recovery was 98.4%,RSD =1.5%（n=6） and the total sugars of solids in aqueous extract was 30.6% while it was 13.4% in acetone extract and the average recovery was 97.9%,RSD =1.2%（n=6）.Conclusions The method can improve the absorption peak remarkablywith differential spectrophotometry（ΔA method）to eliminate the colored matrix interference,which can prove a reliable and repeatable method for determination of total sugars in organic solvent extractions.