加拿大一枝黄花黄酮类成分及抗氧化与自由基消除活性的研究

 目的研究外来植物加拿大一枝黄花中黄酮类成分及其抗氧化和自由基消除活性。方法应用多种色谱技术进行分离纯化,应用MS和NMR技术鉴定化合物的结构,采用1,1-二苯基苦味基苯肼(DPPH)自由基消除实验进行抗氧化和自由基消除活性的研究。结果从加拿大一枝黄花的甲醇提取物中分离鉴定出9个黄酮类化合物,分别鉴定为:槲皮素(1)、3-甲氧基槲皮素(2)、槲皮素-3-O-β-D-葡萄糖苷(3)、槲皮素-3-O-α-L-鼠李糖苷(4)、芦丁(5)、山柰酚(6)、山柰酚-3-O-β-D-葡萄糖苷(7)、山柰酚-3-O-α-L-鼠李糖苷(8)、山柰酚-3-O-芦丁糖苷(9);自由基消除实验发现,与维生素C相比,化合物1的抗氧化和自由基消除活性最强,化合物2和3显示出中等活性,化合物4~9的活性较弱。结论化合物2,4,8和9首次从该植物中得到,加拿大一枝黄花中的黄酮类成分具有较强的抗氧化和自由基消除活性,其活性强弱与分子结构相关。

Antioxidant and Radical-Scavenging Activity of Flavonoids From Solidago canadensis

OBJECTIVE To investigate the flavonoids of an exotic herb,Solidago canadensis.METHODS The compounds were separated by different chromatographies and the structures were determined mainly by means of MS and NMR techniques;antioxidant and radical-scaveging activity of all the isolated compounds were evaluated by DPPH radical-scavenging assay.RESULTS Nine flavonoids were obtained from the methyl extract of S.canadensis and determined as quercetin(1),3-methoxy-quercetin(2),quercetin-3-O-β-D-glucopyranoside(3),quercetin-3-O-α-L-rhamopyranoside(4),rutin(5),kaempferol(6),kaempferol-3-O-β-D-glucopranoside(7),kaempferol-3-O-α-L-rhamopyranoside(8) and kaempferol-3-O-rutinnoside(9),respectively.DPPH radical-scavenging assay displayed that compound(1) owned the most strong activity,compared to the positive control of Vit C.Compound(2) and(3) showed moderate activity while compound(4～9) exhibited more weaker activity than that of Vit C.CONCLUSION Compound 2,4,8 and 9 are isolated in this plant for the first time.The flavonoids from S.canadensis possesses pretty strong activity of antioxidant and radical-scavenging and the relationships between the molecular structures and activity are also discussed.