银杏叶黄酮类成分体外及经肠吸收后抗氧化活性比较

Comparing the antioxidant activity of the in vitro and intestinal absorption of Ginkgo biloba flavonoids

关键词:  银杏黄酮  DPPH自由基  肠吸收  抗氧化活性

Key words:  Flavonoids  DPPH radical  intestinal absorption  antioxidant activity

摘要:

[目的] 比较银杏叶提取物中三个主要的银杏黄酮苷元体外及经肠吸收后抗氧化活性.[方法] 采用1,1-二苯基-2-三硝基苯肼(DPPH)法(1,1-二苯基-2-三硝基苯肼法)测定模型药物体外及肠吸收液对自由基的清除作用,测定药物的抗氧化活性.[结果] 槲皮素、异鼠李素、山奈酚体外清除DPPH自由基的EC50分别为78.6 μm,203.2 μm,222.0 μm;药物肠吸收液DPPH清除率趋势为:槲皮素>异鼠李素>山奈酚,其清除率较体外相比有所降低;3个单体不同配比的肠吸收液DPPH清除率显示以提取物中所含比例混合清除率数据高于其他两组.[结论] 3个单体体外及肠吸收液均能够清除DPPH自由基,且清除能力为:槲皮素>异鼠李素>山奈酚;肠吸收后药物清除率下降,可能与单体在肠道中产生分解有关,其原因还需进一步探讨,3个单体以提取物所含比例混合后抗氧化活性要好.

Abstract:

[Objective] To compare the antioxidant activity of three main flavonoids aglycone from Ginkgo biloba extract in vitro and intestinal absorption. [Methods] Using DPPH (2, 2-diphenyl-1-picryl-hydrazyl-hydrate) radical method and measuring the antioxidant activity of the drugs in vitro and after intestinal absorption. [Results] DPPH radical scavenging capacity: Its EC50 were 78.6, 203.2, 222.0 μm, respectively. The trend of intestinal absorption was: Quercetin> Isorhamnetin> Kaempferol, its clearance rate decreased compared to the data in vitro; three different ratios of intestinal absorption displayed the DPPH clearance of the extract mixing ratio was higher than the others. [Conclusion] Three monomers in vitro and fluid of intestinal absorption are able to scavenge DPPH radical and the ability is: Quercetin> Isorhamnetin> Kaempferol; the reason of intestinal absorption clearance rate decrease may be the monomers break down in the gut and reasons need to further investigate. The intestinal absorption of antioxidant capacity of monomer mixed by the extract ratio shows higher than other proportions.