高效液相色谱-荧光检测法测定桑叶中1-脱氧野尻霉素(DNJ)含量

目的:建立桑叶药材中1脱氧野尻霉素(DNJ)的高效液相色谱荧光检测法的含量测定方法。并对不同生长季节和生长环境桑叶药材的DNJ含量进行测定。方法:桑叶经0.05mol·L^-1盐酸提取,在pH8.5的硼酸盐缓冲液条件下,用芴甲氧酰氯(FMOC Cl)与DNJ反应生成荧光产物,然后用高效液相色谱荧光检测器测定。液相条件为HiQSiLC₁₈分析柱(4.6mm×250mm,5μm),流动相为乙腈0.1%醋酸(55∶45),流速1.0mL·min^-1,柱温25℃,荧光检测器激发波长254nm,发射波长322nm。结果:DNJ与其他组分分离效果较好,线性范围为0.567～34μg·mL^-1(r=0.9998),加样回收率为97.2%。结论:桑叶中DNJ含量与环境因素、温度及生长季节有关,该方法可作为桑叶药材的质量控制方法。

Determination of 1-deoxynojirimycin in leaves of Morus alba by high performance liquid chromatography with fluorescence detection

OBJECTIVE: To develop a high performance liquid chromatographic method for the determination of DNJ in Morus alba leaves with fluorimetric detection after precolumn derivatization with 9-fluorenylmnethyl chlorformate (FMOC-Cl). METHOD: DNJ in Morus alba leaves was extracted with 0.05 mol x L(-1) HCl, reacted with FMOC-Cl, and separated on a HiQSiL C18 column at 250 degrees C. Mobile phase consisted of acetonitrile-0.1% aqueous acetic acid (55:45) with a flow rate of 1.0 mL x min. The fluorescence detector was operated at lambdaEX = 254 nm, lambdaEM = 322 nm. RESULT: A satisfactory separation between DNJ and impurity was obtained. The calibration curve was linear over the concentration range from 0.567 microg x mL(-1) to 34 microg mL(-1), r = 0.9998. The average recovery was 97.2%. The contents of DNJ in M. alba collected in different seasons and grown in different environment were determined. CONCLUSION: The quantity of DNJ in leaves of M. alba is related to the environment factor, temperature and growing period. The method can be used for qualioy control of the medicinal material.