RP-HPLC法测定不同采收期贼小豆中9种有机酸含量

Content of nine organic acids in Vigna minima(Roxb.) in different harvest periods by reversed phase high performance liquid chromatography

为充分利用野生贼小豆资源,建立利用反相高效液相色谱同时测定贼小豆中9种有机酸含量的方法,了解不同采收期贼小豆中有机酸的动态变化,以郑州市区同一位置的野生贼小豆为样品,采用SunfireTM-C18色谱柱,pH=2.7的磷酸盐缓冲溶液为流动相,在紫外光210 nm处检测。结果表明:25 min内可完成9种有机酸的基线分离,检测限为0.12～6.00 mg/L。各有机酸标准曲线的相关系数为0.9965～0.9998,加标回收率均值为96.01%～101.10%,相对标准偏差为0.56%～1.9%(n=6)。贼小豆样品含有所测定9种有机酸中的7种,其中,酒石酸、柠檬酸、琥珀酸和顺丁烯二酸含量较高。8月下旬和9月下旬采集样品中所测有机酸的总含量相对较高,9月下旬采集样品中柠檬酸和琥珀酸含量较高。该方法分析速度快、灵敏度高、分离效果和重现性好,可用于贼小豆中有机酸含量的测定。

In order to develop and utilize Vigna minima（Roxb.） Ohwi et Ohashi resources, and to understand the dynamic changes of organic acids in different harvest period, a method of simultaneous determination of 9 organic acids content by reversed phase-high performance liquid chromatography （RP-HPLC） was established with wild Vigna minima （Roxb.） at the same location of Zhengzhou as samples, which used SunfireTM-C18 column, pH=2.7 phosphate buffer solution as mobile phase, the 210 nm ultraviolet detection. The results showed that the baseline separation of 9 kind of organic acids could be finished within 25 min; the detection limit was 0.12-6.00 mg/L, the correlation coefficient was 0.9965-0.9998 on standard curves of organic acids, average recovery rate was 96.01%-101.10%, the relative standard deviation （RSD） was 0.56%-1.9%（n=6）. The samples contained 7 kinds of organic acids, in which tartaric acid, citric acid, succinic acid and maleic acid content were higher. The total content of organic acid in the late August and late September collected samples were higher relatively, the content citric acid and succinic acid were higher in late September samples. This method was validated to be fast, high sensitivity, good separation and reproducibility for the determination of organic acid content in Vigna minima（Roxb.） samples with satisfactory results.