山楂叶中多元酚类成分抗超氧阴离子活性研究及构效关系分析

 目的研究山楂叶中多元酚类成分对超氧阴离子(O₂^-)的清除能力,探讨其抗氧化活性与结构的关系。方法分别对德国单子山楂(Crataegus monogyna Jaeq.)叶和中国山楂(Crataegus pinnatifida Bge.var.major N.E.Br.)叶中多元酚类成分进行分离;通过化学发光法测定这些成分对邻苯三酚-鲁米诺-碳酸缓冲液(pH 10.2)体系产生的O₂^-的清除能力。结果从2种山楂叶中共分离得到12个多元酚类化合物,经鉴定分别为牡荆素(vitexin,Ⅰ)、2″-O-鼠李糖牡荆素(2″-O-rhamnosylvitexin,Ⅱ)、芦丁(rutin,Ⅲ)、金丝桃苷(hyperoside,Ⅳ)、3-O-β-D-葡萄糖槲皮素(3-O-β-D-glucosylquercetin,Ⅴ)、4″-O-乙酰基-鼠李糖牡荆素(4(?)- O-acetyl-2″-O-rhamnosylvitexin,Ⅵ)、槲皮素(quercetin,Ⅶ)、4″-O-葡萄糖牡荆素(4″-O-glucosylvitexin,Ⅷ)、4(?)-O-鼠李糖芦丁(4(?)-O-rhamnosylrutin,Ⅸ)、6″-乙酰牡荆素(6″-O-acetyl-vitexin,Ⅹ)、绿原酸(chlomgenic acid,Ⅺ)和咖啡酸(caffeic acid,Ⅻ)。抗氧化实验结果表明,12种多元酚类成分中Ⅰ,Ⅱ,Ⅵ,Ⅷ,Ⅹ清除超氧阴离子(O₂^-)活性与维生素C相当,其他成分均比维生素C强。所有成分在一定范围内(清除率在10%～90%之间),量效呈对数关系(y=alogx+b)。构效关系分析显示,其清除超氧阴离子(O₂^-)的活性取决于分子结构,具有明显的结构依赖性。结论山楂叶中多元酚类成分具有明显的清除超氧阴离子活性,是山楂叶抗氧化作用的主要活性成分。

Study on scavenging activities for superoxide anion radicals (O2-) and structure-activity relationship of polyphenolic compounds from leaves of Crataegus

OBJECTIVE To study the scavenging activities of the polyphenolic compounds for superoxide anion (O₂^-) radicals from the leaves of Crataegus L. and to analyze the structure-activity relationship of the compounds.METHODS The polyphenolic compounds were isolated from the leaves of Crataegus pinnatifida Bge.var.major N.E.Br. And Crataegus monogyna Jacq. Their antioxidant activities were compared by scavenging the superoxide anion (O₂^-) radicals generated by the Pyrogallic acid 3-Amino-phthalhydrazid (Luminol)-Na₂CO₃/NaH-CO₃ buffer (pH 10.2) system. RESULTS Twelve polyphenolic compounds were isolated from the leaves of the two species. They were vitexin (Ⅰ), 2″-O-rhamnosylvitexin(Ⅱ), rutin (Ⅲ), hyperoside (Ⅳ), 3-O-β-D-glucosylquercetin (Ⅴ), 4(?)-O-acetyl-2″-O-rhamnosylvitexin (Ⅵ), quercetin (Ⅶ), 4″-O-glucosylvitexin (Ⅷ), 4(?)-O-rhamnosylrutin (Ⅸ), 6″-Oy=alogx + b)over the range of 10% -90% of the scavenging activities. Their scavenging activities for superoxide anion were decided by their structures. CONCLUSION The polyphenolic compounds from the leaves of Crataegus L. possess strong scavenging activities for super-oxide anion(O₂^-), and are the main antioxidants in the leaves of Crataegus L.