Duan Xuewu, Wu Genfu, Jiang Yueming
South China Botanical Garden, The Chinese Academy of Sciences, Guangzhou Leyiju 510650, PR China.
Molecules. 2007 Apr 11;12(4):759-71. doi: 10.3390/12040759.
Phenolics were extracted from litchi fruit pericarp (LFP) tissues, purified and their antioxidant properties analyzed. LFP phenolics strongly inhibited linoleic acid oxidation and exhibited a dose-dependent free-radical scavenging activity against alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH*) and hydroxyl radicals and superoxide anions. The degradation of deoxyribose by hydroxyl radicals was inhibited by phenolics acting mainly as iron ion chelators, rather than by directly scavenging the radicals. Phenolics from litchi fruit pericarp were found to display similar reducing power activity as ascorbic acid. The effect of phenolic compound treatment on pericarp browning and electrolyte leakage of litchi fruit was also evaluated and it was observed that application of exogenous litchi phenolics to harvested litchi fruit significantly prevented pericarp browning and delayed increases in electrolyte leakage. These results suggest that litchi pericarp tissue phenolics could be beneficial in scavenging free radicals, maintaining membrane integrity and, thereby inhibiting pericarp browning of litchi fruit.
从荔枝果皮(LFP)组织中提取酚类物质,进行纯化并分析其抗氧化特性。LFP酚类物质强烈抑制亚油酸氧化,并对α,α-二苯基-β-苦味酰基自由基(DPPH*)、羟基自由基和超氧阴离子表现出剂量依赖性的自由基清除活性。酚类物质主要作为铁离子螯合剂,而非直接清除自由基,从而抑制了羟基自由基对脱氧核糖的降解。发现荔枝果皮中的酚类物质具有与抗坏血酸相似的还原能力活性。还评估了酚类化合物处理对荔枝果实果皮褐变和电解质渗漏的影响,观察到将外源荔枝酚类物质应用于采收后的荔枝果实可显著防止果皮褐变并延缓电解质渗漏的增加。这些结果表明,荔枝果皮组织中的酚类物质可能有助于清除自由基、维持膜完整性,从而抑制荔枝果实的果皮褐变。