银杏叶总黄酮正交提取工艺优化及其抗氧化能力与抑制亚硝化反应研究

Optimization of Flavonoid Extraction Technology of Orthogonal from Ginkgo Folium and its Antioxidation Ability

目的:测定银杏叶总黄酮抗氧化能力、对亚硝酸盐的清除能力及对亚硝胺合成的抑制能力。并考察各指标相关性。方法:正交设计试验确定从银杏叶中提取黄酮类物质的最佳条件,测定0.1,0.2,0.4,0.6,0.8,1.0,2.0 g·m-1银杏叶总黄酮总抗氧化能力血浆铁还原能力(FRAP),二苯代苦味酰基自由基(DPPH·自由基)清除率,亚硝酸盐清除率及对二甲基亚硝胺(NDMA)阻断作用。结果:浸提温度80℃,浸提1 h,乙醇浓度75%,料液比1∶15是提取银杏叶总黄酮的最佳条件,提取率为8.86%。总抗氧化能力和DPPH·清除率随总黄酮质量浓度增高而增强;对亚硝酸盐有很强的清除作用并能阻断亚硝胺的合成,和总黄酮质量浓度成正相关。结论:银杏叶总黄酮有很强的抗氧化及清除亚硝酸盐及阻断亚硝胺合成的能力。

Objective： To define the optimum flavonoid extract program from Ginkgo Folium leaf and its antioxidant activity.Method： Orthogonal experiment was applied to define the optimum extract program.The ability of oxygen radical absorbance capacity was determined by 2,2-diphenyl-1-picrylhydrazyl（DPPH·） method,Total antioxidant capacity was evaluated by Ferric reducing antioxidant power（FRAP） value.Inhibition of nitrosation reaction was predicated by the cleaning of nitrite and the blocking rate of nitrosodimethylamine（NDMA）.Result： The optimum extraction program（8.65%） could be obtained under the condition of 80 ℃,material ratio 1∶ 15 by the 75% alcohol for 1 h.The ablility of total antioxidant capacity and DPPH·clearance is enhanced at a dose-dependent manner with the concentration of the extract.Conclusion： The flavonoid extract from Ginkgo Folium have strong antioxidation ability and could block nitrosamine synthetise.