Antioxidation and phenolic constituents in Xinjiang wild apple[Malus sieversii (Lebed.) Roem.] leaf

Chino. 为探讨新疆野苹果的遗传多样性提供基本资料，并为揭示新疆野苹果抗氧化作用的物质基础提供科学依据。以35株野生新疆野苹果的叶片为试材，DPPH、FRAP和TEAC法测定总抗氧化能力，并测定清除羟自由基和超氧自由基能力，Folin-Ciocalteau法测总酚，HPLC测多酚组分，相关系数法分析抗氧化能力与多酚含量的相关性。参试的新疆野苹果单株之间抗氧化能力存在明显差异，5种方法抗氧化能力变异系数为16%～35%，极值比为1.61～7.33；HPLC鉴定出没食子酸、绿原酸、儿茶酚、香豆酸、阿魏酸、咖啡酸、根皮苷、杨梅黄酮、槲皮素和肉桂酸等10种成分，其中根皮苷和杨梅黄酮含量较高，且这些组分含量及总酚含量单株之间存在差异；新疆野苹果总抗氧化能力与其总酚和原花青素含量极显著正相关。参试的新疆野苹果单株抗氧化能力及酚类物质组分含量存在明显差异，新疆野苹果抗氧化作用与其酚类物质关系密切。

Inglés. To provide data base for genetic diversity in Malus sieversii (Lebed.) Roem. and basic information for substance bases of antioxidant capacity in the species. The leaves collected from 35 wild M. sieversii trees were used as materials, and FRAP, TEAC, DPPH radical-scavenging, hydroxyl radical-scavenging and superoxide radical radical-scavenging assay were conducted. Total phenolic content was measured using the Folin-Ciocalteau method. Phenolic constituents were identified by HPLC and the correlation between antioxidant capacity and phenolic content was measured with Pearson correlation coefficient. There were remarkable differences in antioxidant capacities between the examined M. sieversii seedlings because the coefficient of variations of the antioxidant capacity estimated by the five methods were between 16% to 35% and the extremal value rates of those were between 1.61-7.33. Gallic acid, chlorogenic acid, cinnamic acid, coumaric acid, ferulic acid, caffeic acid, phlorizin glucoside, myricetin, quercetin and catechin were identified by HPLC, in which phlorizin glucoside and myricetin existed in high concentraions, respectively. There were extensive variations in contents of these phenolic compounds and in total phenolic content between the examined seedlings. Extremely significant correlations were found between antioxidant capacity and total phenolic content, between antioxidant capacity and proanthocyanidin content, respectively. There were significant differences in antioxidant capacities and in phenolic constituent contents between examined M. sieversii seedlings. There is an intimate relation between antioxidant capacity and phenolics in M. sieversii.