离子液体提取分离鹿藿中异黄酮化合物

Extraction and Separation of Isoflavonoids from Rhynchosia volubilis Lour Using Ionic Liquid

以1-丁基-3-甲基咪唑四氟硼酸盐([Bmim]BF4)离子液体取代天然产物研究中的溶剂,对具有抗雄性生育活性和抑菌作用的鹿藿根中的异黄酮成分进行提取和分离。从鹿藿根的70%乙醇粗提物中,成功分离纯化得到3种异黄酮类化合物,它们均是首次从植物鹿藿中分离得到。经过波谱分析鉴定,3种化合物的结构被确定为木豆酮(Cajanone)、鸡豆黄素A(Biochanin A)和1种新的异黄酮类化合物,被命名为3-[4'-(1″-甲氧基)-丙基氧代]-苯基-5,7-二羟基异黄酮(3-[4'-(1″-methoxy)-propoxy]-phenyl-5,7-dihydroxy-isoflavone)。建立了植物鹿藿中异黄酮含量的测定方法:以木豆酮化合物为标准品,在其紫外最大吸收峰270 nm处,测得生药中总异黄酮的含量为0.73%;测得平均加样回收率99.94%,相对标准偏差3.66%,离子液体回收率76.7%。

The ionic liquids have been known as ＂green＂ or ＂environmentally friendly＂ solvents and show potentials to replace traditional solvents.A new approach was set up for the extraction and separation of isoflavonoids from the Rhynchosia volubilis Lour using the 1-butyl-3-methyl tetrafluoroborate（BF4） ionic liquid.Three isoflavonoids were obtained from the 70% alcohol extract of Rhynchosia volubilis.Based on the spectra analysis,their structures have been confirmed to be cajanone,3-[4′-（1″-methoxy）-propoxy]-phenyl-5,7-dihydroxy-isoflavone and Biochanin A,in which the 3-[4′-（1″-methoxy）-propoxy]-phenyl-5,7-dihydroxy-isoflavone is a novel compound.The result had shown that the BF4 could extract isoflavones effectively and selectively.A protocol for determining the content of each component in the isoflavonoid was established.The overall pharmacognosical content of isoflavone was 0.73% using cajanone as the standard and its maximum absorption（270 nm） as the determination wavelength.The average recovery rate and relative standard deviation was 99.94% and 3.66%,respectively.The recycling rate of the ionic liquid was 76.7%.