木薯叶片中黄酮醇类物质的提取与检测

Extraction and Detection of Flavonols from Cassava Leaves

【目的】以木薯叶片为试材,对木薯叶中芦丁、烟花苷、槲皮素和山奈酚的提取和检测方法进行了探索和优化。【方法】在70℃条件下,以40%(芦丁、烟花苷)和80%(槲皮素、山柰酚)的乙醇水溶液,料液比1/75(g/mL)超声提取30 min;HPLC分析四种黄酮醇时,流动相以甲醇0.2%的磷酸水溶液进行二元梯度洗脱,检测波长为360 nm,流速为0.8 mL/min,柱温为40℃。【结果】可有效提取和分离木薯叶片中芦丁、烟花苷、槲皮素;4种黄酮醇类物质线性关系良好,相关系数(R^2)>0.9992,检出限为0.02~0.10μg/mL;方法的精密度、重复性和稳定性的标准偏差(RSD)都低于4.00%;样品的加标平均回收率为90.81%~99.83%,方法的准确度较好,RSD<2.84%。对三个木薯品种不同生育期的叶片中4个黄酮醇含量进行测定,其含量呈现嫩叶期>幼叶期>成熟叶的趋势。【结论】该提取和检测方法简单、准确,重复性好,能实现不同生育期和不同品种木薯叶中4种黄酮醇类物质的同时测定。

【Objective】The objective of the study was to develop a method to extract and detect rutin,kaempferol-3-O-rutinoside,quercetin,and kaempferol from cassava leaves.【Method】The extraction was conducted at 70℃with 40%(rutin,kaempferol-3-O-rutinoside)and 80%(quercetin and kaempferol)ethanol aqueous solution.The liquid/solid ratio was 1/75(g/mL)and ultrasonic extraction time was 30min.The mobile phase was eluted with methanol 0.2%phosphoric acid aqueous solution.The detection wavelength was 360 nm,the flow rate was 0.8 mL/min and the column temperature was 40℃.【Result】The results showed that the method could effectively extract and isolate rutin,fireworks glycosides,and quercetin.The linear relationship of the four flavanols(rutin,kaempferol-3-O-rutinoside,quercetin and kaempferol)was good(R 2>0.9992),and the detection limit were 0.02-0.10μg/mL.The accuracy of the method is good:the standard deviation(RSD)of precision,repeatability and stability of the method is less than 4.00%;the average recovery of the sample is 90.81%-99.83%,and RSD<2.84%.By applying this method,the contents of flavonols in different growth stages and different varieties of cassava leaves were determined.The flavonols contents order were unfolded young leaves>young leaves>mature leaves.【Conclusion】The extraction and detection method is simple,accurate and reproducible,and can simultaneously determine four flavonols in different growth stages and different varieties of cassava leaves.