?莓茶代用茶总黄酮检测方法优化
2020-12-21张学英



摘 要:为了建立准确、简便、灵敏、重现性好的莓茶代用茶中总黄酮(以二氢杨梅素计,下同)的检测方法,特对检测试剂、检测波长、显色反应条件等进行优化。结果表明:用70%乙醇50℃超声提取4次(提取率达99.814%),以三氯化铝和醋酸钾进行显色反应,在294 nm波长处检测吸光度值,获得标准曲线方程Abs =0.043 74 C×0.012 36,相关系数为0.999 94,线性范围2.48~19.84 μg/mL。经验证,该检测方法重现性良好,相对标准偏差RSD(n=5)为0.980 7%;精密度良好,相对标准偏差RSD(n=5)为0.092 9%~0.415 5%;显色反应1 h内稳定性良好,吸光度值及检测浓度值相对标准偏差RSD(n=5)为0.565%~1.178%。该方法最低检测浓度为0.35 μg/mL。
关键词:莓茶代用茶;总黄酮;二氢杨梅素;检测方法;优化
中图分类号:S567; O652 文献标识码:A文章编号:1006-060X(2020)10-0098-05
Abstract: To develop an accurate, simple, sensitive and repeatable method for the detection of total flavones (calculated in dihydromyricetin) in Ampelopsis grossedentata tea-like drink (one of tea substitutes), the optimization for test reagents, detection wavelength selection and color reaction was made. Ultrasonic extraction was conducted with 70% ethanol at 50 °C for 4 times (the extraction rate was 99.814%), color reaction was performed with aluminum trichloride and potassium acetate, the absorbance value was measured at 294 nm, then a standard curve equation Abs =0.043 74×C-0.012 36 was constructed where the correlation coefficient was 0.999 94, and the linear range was 2.48~19.84 μg/mL. The results have proved that the method is of a good repeatability with the relative standard deviation RSD (n=5) of 0.980 7% , and high accuracy with the RSD (n=5) of 0.092 9%~0.415 5%. The color reaction is stable within 1h, and the RSD (n=5) is 0.565%~1.178% for the absorbance value and the detected concentration value. The minimum detection concentration of this method is 0.35 μg/mL.
Key words: Ampelopsis grossedentata tea-like drink; total flavones; dihydromyricetin; detection method; condition optimization
葡萄科蛇葡萄属显齿蛇葡萄(Ampelopsis grossed-entata),俗名莓茶,又称为藤茶、茅岩莓等。莓茶是一种野生藤本植物,广泛分布于我国湖南、湖北、贵州、江西等省份,其鲜叶可加工成莓茶代用茶,故被广泛人工种植。湖南省湘西州种植莓茶历史悠久,有“溪洲莓茶”、“永顺莓茶”(国家农产品地理标志登记,己通过评审)等标志或品牌[1]。2013年12月24日原国家卫生和计划生育委员会,将莓茶叶纳入可用于食品生产加工的新食品原料管理[2],从此,莓茶代用茶纳入我国食品生产许可发证范围。2019年国家卫健委将莓茶叶列入最新版食药同源目录[3],由此开启莓茶叶食药两用新用途的广阔发展空间。近年来莓茶代用茶产业己成为湘西自治州永顺县和凤凰县脱贫攻坚及乡村振兴的政府扶持项目。同时莓茶食用药用价值研究成为广大科研工作者的研究方向,张红忠等[4]综述了藤茶的植物学研究与加工、化学成分和药理作用;刘慧颖等[5]总结了莓茶的化学成分及药理作用的研究进展;冯涵林等[6]对藤茶中黄酮类成分的功效进行了综述。……
