已有研究表明蓝莓花青素具有较强抗氧化作用，但花青素以何种结构形式存在会具备更强的抗氧化活性国内外尚无系统报道。本文运用组合的浸提、萃取、柱色谱等技术手段研究了蓝莓花青素糖苷及苷元的制备技术，采用紫外光谱、高效液相色谱进行了纯度分析及结构鉴定，并通过考察花青素样品对DPPH和ABTS自由基的清除能力来比较两种样品中抗氧化能力强弱。结果如下：蓝莓花青素糖苷经酸化乙醇浸提、乙酸乙脂萃取、Amberlite XAD-7HP大孔树脂层析分离后，制得了纯度达59.46%的花青素糖苷，并从中鉴定出14种糖苷单体；在此基础上，将糖苷纯化物进行酸水解、层析分离后，制得了纯度为50.58%的蓝莓花青素苷元，从中鉴定出5种苷元单体；得出蓝莓花青素苷元的抗氧化能力显著高于糖苷形式（p<0.05），且为Trolox对照品抗氧化能力的1.31~1.72倍。本研究结果表明，将蓝莓花青素糖苷转化为苷元形式能增强花青素的抗氧化活性。

Several studies have noted the high antioxidant activity of anthocyanins in blueberry fruits. However, there have been no studies on the structural form (glycosides or aglycones) of anthocyanins providing the highest antioxidant activity. In the present study, a combination of extraction (solid-liquid and liquid-liquid) and column chromatography was used for preparing blueberry anthocyanin glycosides and aglycones, and ultraviolet-visible (UV-vis) spectroscopy and high-performance liquid chromatography (HPLC) were used to determine the purity and structure of anthocyanin extracts. The antioxidant activities of two anthocyanin samples were evaluated by the hydroxyl radical (?OH), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging activities. After acid-ethanol solid-liquid extraction, ethyl acetate liquid-liquid extraction, and chromatographic separation on macroporous resins, the anthocyanin glycoside extract was obtained with a purity of 59.46%, and 14 glycoside monomers were identified. Based on this finding, the purified anthocyanin glycoside extract underwent acid hydrolysis and chromatographic separation to yield blueberry anthocyanin aglycone extract with a purity of 50.58%, and five aglycone monomers were identified. The antioxidant capacity of anthocyanin aglycones was significantly higher (p<0.05) than that of glycosides, and was 1.31 to 1.72 times that of the Trolox reference. The results of the present study indicate that transforming anthocyanin glycosides into aglycone forms improve their antioxidant activity.

国家自然科学基金面上项目(31271907)