配位法对银杏叶初提物脱除银杏酚酸的效果

Effects of coordination method on removing ginkgolic acids from extracts of Ginkgo biloba(EGb)

银杏叶提取物(extracts of ginkgo biloba,EGb)具有诸多生物活性,但是其中含有少量具有毒副作用的银杏酚酸,限制了EGb的应用。目前,国内外去除EGb中银杏酚酸的方法主要有有机溶剂法和大孔树脂法。配位法是根据配位化学提出的新方法,即向银杏叶初提物溶液中加入不同金属盐,考查金属盐对银杏酚酸含量的影响。为研究配位法与大孔树脂法、有机溶剂法联合使用的效果,本试验连续采用有机溶剂法(正己烷溶剂洗涤)、大孔树脂法和配位法脱除银杏叶初提物中的酚酸,并以HPLC法监测试验过程中银杏酚酸含量的变化。结果表明,醋酸锰和氯化锌可以有效降低酚酸含量,其机理可能是银杏酚酸能够与金属盐形成配合物。配位法有助于大孔树脂法、有机溶剂法去除银杏叶初提物中的银杏酚酸,可以得到酚酸含量小于5mg/kg的银杏叶提取物。

Extracts of Ginkgo biloba（ EGb） has many biological activities. However,the toxic ginkgolic acids in EGb limit its application. Currently,organic solvent method and column chromatography method were the mainstream ways to remove ginkgolic acids from EGb. Coordination method was a new method based on the theory of coordination chemistry,with which different metal salts were put into EGb solution to examine the effects on the content of ginkgolic acids. In order to study the combined effects of coordination method,organic solvent method and column chromatography method,organic solvent method（ using n-hexane）,column chromatography method（ macroporous resin） and coordination method were continuously used to remove ginkgolic acids from EGb. The content of ginkgolic acids was quantified by high performance liquid chromatography（ HPLC）. The experimental results indicated that the content of ginkgolic acids was decreased by forming complexes with Mn（ Ac）2and Zn Cl2. It could be concluded that coordination method was effective to remove ginkgolic acids from EGb combined with organic solvent method and column chromatography method. The ginkgolic acids content of the obtained EGb was less than 5 mg / kg.