葡萄酒中顺反式白藜芦醇异构体的反相高效液相色谱法测定

Measurements of Resveratrol Isomers in Grape Wine with Reverse-phase High Performance Liquid Chromatography

建立了一种同时检测葡萄酒中功能成分白藜芦醇及其糖苷的4种异构体含量的RP -HPLC方法。通过紫外照射促使白藜芦醇及其糖苷的反式异构体转化 ,以获得顺式异构体标准样品 ,以葡萄酒直接进样方式及水 -乙腈二元梯度洗脱同时测定葡萄酒中白藜芦醇4种异构体含量。4种异构体回收率在92.4%～98.6%之间 ,相对标准偏差在3.06%～5.42%之间。采用本方法测定国产“龙徽”干红葡萄酒中白藜芦醇总量达到6.64mg·L -1,其中80 %以上为反式异构体成分。葡萄酒开启4h和8h后白藜芦醇总量分别减少了18%和38 %,其中反式白藜芦醇糖苷的损失尤为严重。本实验建立的RP -HPLC方法能够简便。

A reverse-phase high-performance liquid chromatographic(RP-HPLC)method for the simultaneˉous determination of four isomers of resveratrol glucoside and resveratrol in grape wine with PDA detection was developed.A sample solution of50μL was directly injected and the water-acetonitrile gradient elution was used.The separated isomers were determined with UVdetector at306nm.The cis-isomers for quantitative deˉtermination were converted fromthe trans-isomers byUVirradiation at366nm.The range of conversion recovˉery was92.4%～98.6%,and the range of RSD was3.06%～5.42%.By using the developed method,the concentration of the total resveratrol isomers in Cabernet Sauvignon grape wine(produced in China)was6.64mg·L -1 ,and over80%of themwere trans-isomers.It was found that the concentrations of the total resveraˉtrol isomers and their glucosides in grape wine decreased significantly upon exposure to atmosphere.