不同品种苹果非浓缩还原汁的多酚组成及与抗氧化能力的关系

目的:通过分析15种非浓缩还原(NFC)苹果汁的多酚组成、抗氧化能力及二者相关性,研究多酚组成对抗氧化能力的贡献,为果汁生产企业在原料果选择方面提供借鉴。方法:制备15个品种的NFC苹果汁,利用超高效液相色谱(UPLC)和体外抗氧化试验分析多酚组成和抗氧化能力(DPPH和ABTS自由基清除能力),通过单因素方差和相关性分析处理试验结果。结果:NFC苹果汁中,单体酚以绿原酸含量最高,表儿茶素没食子酸酯含量最低;大类多酚有原花青素、酚酸和黄酮类3种,其中酚酸含量最高(102~331μg/mL),黄酮含量最低(5~30μg/mL)。不同品种苹果中,“乔纳金”苹果的DPPH自由基清除能力最高为89.1%,“秋香”苹果的ABTS自由基清除能力最强为92.6%。结论:原花青素大类物质是NFC苹果汁体外抗氧化能力的主要贡献者,原花青素B2、表儿茶素和表儿茶素没食子酸酯3种单体酚有较强的DPPH自由基清除能力,而ABTS自由基清除能力更多地依赖于总酚含量。

Analyses of Phenolic Composition and Antioxidant Activities of NFC Apple Juices from Different Cultivars

Objective:By analyzing the polyphenol composition,antioxidant capacity and their correlation of 15 not from concentrate(NFC)apple juice,the contribution of polyphenol composition to antioxidant capacity is studied,providing reference for the juice industry in the selection of raw fruit.Method:Fifteen varieties of NFC apple juice were prepared,and the composition and antioxidant capacity of polyphenols(DPPH and ABTS free radical scavenging capacity)were analyzed by ultra-high performance liquid chromatography and antioxidant experiment in vitro,and the results were obtained by one-way ANOVA and correlation analysis.Results:Among the 15 kinds of monomer phenols in NFC apple juice,chlorogenic acid content was the highest and epicatechin gallate content was the lowest.The main polyphenols were proanthocyanidins,phenolic acids and flavonoids.The content of phenolic acids was the highest(102-331 g/mL)and the flavonoids were the lowest(5-30μg/mL).Among the 15 apple varieties,the DPPH free radical scavenging ability of Jonagold was the highest at 89.1%,and the ABTS free radical scavenging ability of Qiuxiang was the highest at 92.6%.Conclusion:Procyanidines are major contributors to the antioxidant capacity of NFC apple juice in vitro.Three monomeric phenols,procyanidins B2,epicatechin and epicatechin gallate,have strong DPPH radical scavenging ability,while ABTS radical scavenging ability is more dependent on the total phenol content.