不同时期梨枣叶茶抗氧化成分组成及活性差异的分析  

Differences in Antioxidant Components and Activity of Pear Jujube (Zizyphus jujube Mill. cv. Lizao) Leaf Tea among Different Growth Stages

作　　者：徐变娜[1] 王敏[1] 曹静[1] 汪有科[2] 

机构地区：[1]西北农林科技大学食品科学与工程学院,陕西杨凌712100 [2]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《食品科学》2013年第13期34-38,共5页Food Science

基　　金："十二五"国家科技支撑计划项目(2011BAD29B04);陕西省科技统筹创新工程项目(2011KTCL02-02)

摘　　要：目的:探讨不同采收时期梨枣叶茶抗氧化成分的含量、组成及其活性的差异,揭示梨枣叶茶抗氧化功能品质随采收时期的变化规律。方法:以陕北地区5—8月份矮化密植枣园生长的梨枣嫩叶制成的梨枣叶茶为研究材料,比较总酚、黄酮和VC含量及酚类物质的组成及抗氧化能力(总还原力、DPPH自由基清除率和ABTS+.清除率)的差异性。结果:7月、8月加工的梨枣叶茶抗氧化物质含量及抗氧化能力高于5月和6月加工的梨枣叶茶。梨枣叶茶的酚类和黄酮类物质以及VC含量在不同时期呈现出显著性差异(P<0.05),其中总酚含量变化范围为(29.94±0.28)～(42.65±0.56)mg/g(以没食子酸计),黄酮含量变化范围为(16.61±0.39)～(25.21±1.53)mg/g(以芦丁计),VC含量变化范围为136.5～324.6mg/100g。梨枣叶茶检出的酚类物质主要为没食子酸、儿茶素、芦丁和槲皮素,它们的含量在不同时期也存在显著性差异(P<0.05),其中芦丁是含量最高的酚类物质,最高含量达到60.11mg/100g。梨枣叶茶抗氧化能力与总酚和黄酮含量分别呈现显著(P<0.05)和极显著(P<0.01)相关性,与VC含量相关性不大。结论:夏季采收的梨枣叶茶抗氧化活性强,芦丁是构成梨枣叶茶酚类物质最主要的成分。Objective： To investigate the changing patterns of antioxidant components and activity of pear jujube（Zizyphus jujube Mill.cv.Lizao） leaf tea during different growth stages.Methods： The tender leaves of pear jujube trees were selected in five growth stages from May to August followed by pan-firing to produce the tea,and the contents of total phenols,total flavonoids and vitamin C,phenolic compositions,and antioxidant properties including the capability to scavenge DPPH and ABTS free radicals and reducing power were investigated.Results： Antioxidant components and activity of pear jujube leaf tea in July and August were better than in May and June.The contents of total phenols,total flavonoids and vitamin C significantly varied among the different stages（P 0.05）,from（29.94 ± 0.28） to（42.65 ± 0.56） mg galic acid eq./g FW（fresh weight）,from（16.61 ± 0.39） to（25.21 ± 1.53） mg rutin eq./g FW and from 136.5 to 324.6 mg/100 g,respectively.Gallic acid,catechin,rutin and quercetin were detected as major phenolics,and their contents had significant differences among different stages（P 0.05）;rutin was the most abundant among these phenolics,reaching maximum content of 60.11 mg/100 g.Oxidation resistance were significantly correlated with total phenols（P 0.05） and total flavonoids（P 0.01）,but not correlated with vitamin C content.Conclusion： The antioxidant performance of pear jujube leaf tea harvested in summer is better than that in spring,and rutin is the most dominant component of phenolic compounds.

关 键 词：梨枣叶茶 采收时期 抗氧化能力 酚类组成 

分 类 号：TS201.2[轻工技术与工程—食品科学]