薏苡仁油的质量分析

目的：建立薏苡仁油的总酯量测定和薄层色谱鉴别以及气相色谱含量测定法。方法采用容量滴定法测定薏苡仁油的总酯量；采用薄层色谱法鉴别薏苡仁油中的特征成分；采用气相色谱法，经油酸和亚油酸经衍生化处理，以水杨酸甲酯为内标物按内标法计算油酸及亚油酸含量。结果薏苡仁油中总酯量以甘油三酯计，均不低于95％；薄层色谱鉴别斑点清晰，专属性强；气相色谱法定量分析油酸甲酯在0．0544～1．0872 mg／mL范围内呈良好的线性关系，平均回收率为97．92％（RSD＝1．24％，n＝6），亚油酸甲酯在0．0415～1．0508 mg／mL范围内呈良好的线性关系，平均回收率为100．4％（RSD＝2．23％，n＝6），3批薏苡仁油中油酸含量分别为59．59％，58．29％和58．67％，亚油酸含量分别为25．17％，24．31％和24．77％。结论建立的薏苡仁油总酯量测定法、薄层色谱鉴别法及气相色谱（内标法）含量测定方法操作简便，结果准确，可有效用于薏苡仁油的质量控制。

Study on Quality Analysis of Coix Seed Oil

Objective To study triglyceride content in the coix seed oil and to establish a qualita‐tive and quantitative analysis method of coix seed oil . Methods Titration was used to study triglyceride content in the coix seed oil . TLC was applied to identify the characteristic components in the coix seed oil . After derivatization ,gas chromatography was used to determine the content of oleic acid and linoleic acid ,through internal standard method with methyl salicylate as the internal standard substance . Results Total esters content based on triglyceride content in the coix seed oil was not less than 95% . The qual‐itative identification with TLC was specific . Under the GC ,methyl oleate had a good linearity in the range of 0 .054 4~1 .087 2 mg/mL ,and the average recovery was 97 .92% (RSD=1 .24% ,n=6) . The methyl linoleate content was in the range of 0 .041 5~1 .050 8 mg/mL ,while its average recovery was 100 .4% (RSD=2 .23% ,n=6) . In the 3 batches of coix seed oil ,the content of oleic acid were 59 .59% , 58 .29% and 58 .67% ;and the content of linoleic acid were 25 .17% ,24 .31% and 24 .77% . Conclusion T he established method for triglyceride content ,T LC and GC are simple ,accurate and reliable ,w hich can be well used in quality control of coix seed oil .