HPLC-UV法测定植物甾醇中3种甾醇单体的含量

本文建立了一种利用紫外高效液相法(HPLC-UV)测定植物甾醇中菜油甾醇、豆甾醇和β-谷甾醇的方法。采用 Waters Symmetry C₁₈柱(4.6 mm×250 mm,5 μm),以乙腈和水为流动相等度洗脱,柱温30 ℃,流速1.0 mL/min,紫外检测波长为208 nm。实验结果表明:菜油甾醇、豆甾醇和β-谷甾醇在38 min内均能实现基线分离,线性范围分别为2.52~50.30、5.08~101.60、5.10~102.00 μg/mL时,甾醇单体的线性关系良好,相关系数r分别为0.9971、0.9989、0.9991,检测限为2.5 μg/mL;日内精密度在0.06%~3.06%范围内,日间精密度介于1.56%~6.61%;加样回收率介于92.74%~106.25%之间。本方法能够准确测定4种植物甾醇中3种甾醇单体的含量,其中大豆甾醇和木甾醇中3种甾醇单体的含量组成差异较大,大豆甾醇中菜油甾醇和豆甾醇的含量分别为163.80~251.23 mg/g和134.89~235.04 mg/g,远高于木甾醇中的菜油甾醇和豆甾醇含量,而木甾醇中β-谷甾醇含量为(685.10±7.55) mg/g,则明显高于β-谷甾醇在大豆甾醇中的含量。相对现有的高效液相方法,本方法实现了对混合甾醇中菜油甾醇、豆甾醇和β-谷甾醇3种甾醇单体的精确定量分析。

Quantitative Analysis of Three Individual Sterols in Phytosterol by HPLC-UV

This study was aimed to establish a HPLC approach for the quantitative analysis of campesterol, stigmasterol and β-sitosterol in phytosterol. In HPLC analysis, the chromatographic separation was achieved on a Waters Symmetry C₁₈column (4.6 mm×250 mm, 5 μm) with a mobile phase composed of acetonitrile and water at a flow rate of 1.0 mL/min. In addition, detection wavelength and column temperature were set at 208 nm and 30℃, respectively. The results showed that three sterols reached the baseline separation and the concentration ranges of campsterol, stigmasterol and β-sitosterol were 2.52~50.30, 5.08~101.60 and 5.10~102.00 μg/mL respectively. It indicated a good linear relationship and the correlation coefficients of three sterols was 0.9971, 0.9989, 0.9991.The limit of detection was 2.5 μg/mL, the intra-day precision was between 0.06%~3.06% and the inter-day precision was between 1.56%~6.61%, the recovery of the three components was 92.74%~106.25%. This method could accurately measure campesterol, stigmasterol and β-sitosterol in phytosterols from 4 kinds of production places, the content of 3 individual phytosterols from deodorizer distillate and tall oil had great differences. The content of campesterol and stigmasterol in phytosterol was 163.80~251.23 mg/g and 134.89~235.04 mg/g, much higher than content in wood sterol. The content of β-sitosterol in wood sterol was (685.10±7.55) mg/g, which was higer than phytosterol. It could be concluded that this was a better method for quality assessment of campesterol, stigmasterol and β-sitosterol in phytosterol.