摘    要通过对比市场上销售的不同品种不同价格的苹果的多酚、黄酮和VC含量及其抗氧化活性，希望为消费者选择优良的苹果品种提供一定的科学依据。采用Folin-Ciocalteu法、亚硝酸钠-硝酸铝-氢氧化钠比色法及2,6-二氯靛酚法测定7种苹果的多酚、黄酮及VC含量，从DPPH清除率、羟基自由基清除率及还原能力三个方面对抗氧化活性进行比较研究。结果显示，花牛和Gala的总酚和总黄酮含量最高，乔纳金、红富士和金帅的总酚和总黄酮含量较低；Gala的VC含量明显高于其他品种，金帅和红蛇果的VC含量最低，且不同品种间VC含量差异较大；青蛇果和Gala的抗氧化活性较强；抗氧化活性与部分抗氧化物质含量存在一定相关性；VC含量与价格相关性较大，能为消费者选购苹果提供依据。88929

Abstract The guidance for the production and consumption of good quality apple variety was presented through the comparison of the polyphenol, flavonoid and VC contents and antioxidant activity among different apple varieties and prices。 The contents of polyphenol, flavonoid and VC in seven species of apples were determined with the method of Folin-Ciocalteu, sodium nitrite-aluminum nitrate-sodium hydroxide colorimetry and 2,6-dichloroindophenol。 The antioxidant activity was compared from three aspects: DPPH clearance rate, hydroxyl radical scavenging rate and reducing ability。 The results showed that total phenolic content and total flavonoid content were the highest in Hua Niu and Gala, lower in Jonah Gold, Red Fuji and Golden Delicious; The content of VC in Gala was much higher than other cultivars and was lowest in Golden Delicious and Red Delicious, and it was different among different cultivars; Green Delicious and Gala showed higher antioxidant activity; There was some correlation between antioxidant substances and antioxidant activity, but not significant; The content of VC had significant correlation with the price, and it can provide suggestion for consumers to buy apples。

毕业论文关键词：苹果；多酚；黄酮；VC；抗氧化活性

Keyword: Apple；Polyphenol；Flavonoid；VC；Antioxidant activity

目    录

1引言 3

2材料与方法 4

2。1材料与源Y于U优I尔O论P文W网wwW.yOueRw.com 原文+QQ75201-8766 试剂 4

2。2苹果原料的预处理 5

2。3苹果中总酚含量的测定 5

2。3。1标准曲线的建立 5

2。3。2总酚含量的测定 5

2。4苹果中黄酮的含量测定 5

2。4。1标准曲线的建立 5

2。4。2总黄酮含量的测定 6

2。5 苹果中VC含量的测定 6

2。5。1 2,6-二氯靛酚染料滴定度的测定 6

2。5。2 VC含量的测定 6

2。6 苹果抗氧化指标的测定 7

2。6。1 DPPH清除率的测定 7

2。6。2羟基自由基清除率的测定 7

2。6。3还原能力的测定 7

2。7 数据统计与分析 8

3结果与分析 8

3。1苹果中多酚、黄酮和VC含量的比较 8

3。2苹果抗氧化活性的比较 10