A-type procyanidins from Litchi chinensis pericarp with antioxidant activity
- 作者：Liang Liu ; Bijun Xie ; Shaoqian Cao ; Erning Yang ; Xiaoyun Xu ; Shanshan Guo
- 关键词：Litchi ; Procyanidins ; Identification ; Antioxidant activity
- 刊名：Food Chemistry
- 出版年：2007
- 期刊代码：48_03088146
- 类别：abs
- 出版时间：2007
- 卷：105
- 期：4
- 页码：1446-1451
- 文件大小：168 K
摘要
The main oligomeric procyanidins from litchi pericarp (Litchi chinensis) were isolated and identified. Complete assignment of epicatechin-(4β→8, 2β→O→7)-epicatechin-(4β→8)-epicatechin structure was obtained using CD, NMR and ESI-MS techniques. The known (−)-epicatechin and procyanidin A2 were also isolated from litchi pericarp. The effects of oligomeric procyanidins, A2 and epicatechin-(4β→8, 2β→O→7)-epicatechin-(4β→8)-epicatechin from litchi pericarp on free radical-scavenging were determined by using a chemiluminescent method. The results showed that all of them had a strong scavenging effect on 
OH, and the IC50 values were 2.60 μg/ml, 1.75 μg/ml and 1.65 μg/ml for oligomeric procyanidins, A2 and the trimeric procyanidins, respectively. The antioxidant activities of A-type dimeric and trimeric procyanidins seemed to be related to the number of hydroxyls in their molecular structures.