薄荷酚类对照提取物HPLC含量测定研究及其在薄荷药材质量控制中的应用

目的：制备薄荷酚类对照提取物，探讨选择对照提取物替代单体成分对照品对薄荷药材质量控制的可行性。方法：采用色谱分离技术制备薄荷酚类对照提取物，建立以对照提取物为对照的薄荷药材HPLC含量测定方法，使用C₁₈色谱柱（4.6 mm×150 mm，5 μm），流动相为乙腈（A）-0.5%甲酸水溶液（B），梯度洗脱（0~15 min，10% A→21% A；15~20 min，21% A→24% A；20~23 min，24% A→25% A；23~29 min，25% A→26% A；29~40 min，26% A→28% A；40~50 min，28% A→30% A；50~60 min，30% A），流速1 mL·min^-1，检测波长296 nm；同时以橙皮苷、香叶木苷、香蜂草苷、蒙花苷及迷迭香酸对照品为对照，对不同批次的酚类对照提取物进行标定，并分别采用对照提取物法和对照品法对薄荷药材进行HPLC含量测定。结果：以对照提取物为对照，橙皮苷、香叶木苷、香蜂草苷、蒙花苷、迷迭香酸的量分别在0.003 45~0.345、0.007 52~0.752、0.001 59~0.159、0.006 74~0.674、0.006 19~0.619 μg范围内线性关系良好；10批对照提取物中上述5个指标性成分的含量分别为5.35%~8.84%、17.09%~25.44%、3.23%~5.41%、12.87%~20.31%、10.72%~20.09%，且不同方法的薄荷药材HPLC含量测得结果基本一致。结论：薄荷酚类对照提取物可用于薄荷药材质量控制，替代单体对照品对药材进行质量控制。

Objective: To prepare phenolic reference extract (PRE) of mint,and explore its feasibility to replace in reference substances in quality control of traditional Chinese medicine.Methods: PRE of mint was obtained by chromatographic separation as the reference for the assay of the herb.The analysis was performed on a C₁₈ column(250 mm×4.6 mm,5 μm) using acetonitrile(A) and 0.5% acetic acid(B) as the mobile phase with gradient elution(0-15 min,10%A→21%A;15-20 min,21%A→24%A;20-23 min,24%A→25%A;23-29 min,25%A→26%A;29-40 min,26%A→28%A;40-50 min,28%A→30%A;50-60 min,30%A).The flow rate was 1.0 mL·min^-1 and the detection wavelength was 296 nm.In the meantime,an HPLC analytical method-based on the PRE was developed to determinate the content of the makers.Results: Based on the PRE,the method had a good linearity in the ranges of 0.003 45-0.345 μg for hesperidin,0.007 52-0.752 μg for diosmin,0.001 59-0.159 μg for didymin,0.006 74-0.674 μg for linarin,0.006 19-0.619 μg for rosmarinic acid,and the quantitative method was validated and the content ranges were 5.35%-8.84% for hesperidin,17.09%-25.44% for diosmin,3.23%-5.41% for didymin,12.87%-20.31% for linarin and 10.72%-20.09% for rosmarinic acid,respectively.The determination results of three methods were compared(reference substances and PRE as reference,respectively),and the results demonstrated that there was no significant difference among the three methods.Conclusion: The presented method which has been proved can be used for the quality control of mint,and will also replace the reference substance to control the quality of traditional Chinese medicine.