HPLC-ELSD测定白花丹药材中的β-谷甾醇

Determination of β-sitosterol in Plumbago zeylanica L. by HPLCELSD

目的建立测定白花丹药材中β-谷甾醇含量的方法,并比较白花丹药材不同药用部位、不同产地和不同采收期中β-谷甾醇的含量。方法采用高效液相色谱-蒸发光散射检测法,色谱柱为Kromasil C18柱(250mm×4.6mm,5μm),流动相为甲醇,流速为1.0mL·min-1,柱温为30℃,漂移管温度为40℃,载气(N2)压力3.5bar。结果β-谷甾醇1.080～4.860μg与峰面积的自然对数呈良好的线性关系(r=0.9995),平均回收率为99.80%。白花丹根、茎中β-谷甾醇的含量分别为0.2074、0.4064mg·g-1,叶中未测到;测得广西产白花丹中的含量普遍低于云南所产,西双版纳南药园的白花丹中β-谷甾醇含量最高;不同采收期白花丹茎中β-谷甾醇的含量较高。结论所建方法简便、准确、重复性好,可以作为控制白花丹药材质量的方法之一。

OBJECTIVE To establish an RP - HPLC method to determine β- sitosterol in different medical parts, different habitats and collection time of Plumbago zeylanica L. METHODS Samples were determined by HPLC - ELSD. Kromasil C18 column was used with a mobile phase of pure methanol with the flow rate of 1.0 mL·min^-1 and the column temperature of 30℃. The temperature in drift tube of was 40℃ and the pressure of N2 was 3.5 bar. RESULTS The method displayed a good linearity within the concentration ranges of 1.08 0 - 4. 860μg （ r = 0. 9995 ）. The average recovery was 99.80%. The contents of β- sitosterol in Plumbago zeylanica L. was as following ：in different medical parts, root was 0. 2074 mg·g ^- 1 with stem 0. 4064 mg·g ^-1, but was not found in leaf. The stems, among different habitats, the content of β-sitosterol in Yunnan province was 0. 4092 and 0. 3785 mg·g ^-1, which were higher than those of Guangxi province. As for the content in different collection time of Plumbago zeylanica L. ,there was no significant differences. CONCLUSION This method is simple, accurate, replicate and suitable for the determination of β- sitosterol in Plumbago zeylanica L.