摘要:以银杏粉为原料，以高效液相色谱(HPLC)测定分配系数的方法优选高速逆流色谱(HSCCC)分离银杏黄酮的最佳溶剂体系，探讨高速逆流色谱仪的流动相流速、转速、分离温度等因素对银杏黄酮成分分离的影响。最终方案确定了最佳的HSCCC分离条件：溶剂体系为正己烷-乙酸乙酯-甲醇-水(4.5:5.5:5:5，v/v)，流速2 mL/min、转速800 r/min、分离温度25 °C，经HSCCC，在银杏叶提取物中分离得到三种黄酮类化合物，经HPLC分析为槲皮素、山奈酚、异鼠李素，纯度都达到90%以上。
对分离得到的槲皮素、山奈酚和异鼠李素进行抗氧化性分析，结果表明具有一定的清除羟基自由基和DPPH自由基能力，清除能力与浓度呈较明显的量效关系；稳定性分析实验表明，银杏黄酮类化合物对温度、时间和光照等具有较好的稳定性，适用于食品生产。
关键词 银杏黄酮；高速逆流色谱分离；槲皮素；山奈酚；异鼠李素；抗氧化性；稳定性
Abstract:Ginkgo powder as raw material, measured by high performance liquid chromatography (HPLC) method of distribution coefficient is preferably high-speed countercurrent chromatography (HSCCC) separation solvent system to explore the high-speed counter-current chromatography mobile phase flow rate, speed, separation temperature and other factors of Ginkgo flavonoids isolated. Determining the optimum HSCCC separating conditions: solvent system of n-hexane - ethyl acetate - methanol - water (4.5:5.5:5:5, v/v), flow rate of 2 mL/min, the rotational speed of 800r/min, separation temperature 25 °C, HSCCC, Ginkgo biloba extract isolated components of three flavonoids, quercetin, kaempferol, isorhamnetin, purity by HPLC analysis was more than 90%.
Isolated quercetin, kaempferol and isorhamnetin oxidation resistance analysis results show that the scavenging DPPH radical scavenging ability and concentration showed an obvious dose-effect relationship; stability The experiments show that, the Ginkgo flavonoids has good stability under alkaline conditions of temperature, time and light, suitable for food production.
Keywords Ginkgo flavonoids High-speed counter current chromatography Quercetin Kaempferol Isorhamnetin Antioxidant activity Stability
