摘要
目的:对冬枣中的黄酮类物质进行分析及抗氧化活性研究。方法:粉碎冬枣用60%乙醇提取,提取物经过大孔树脂初步分离后得到黄酮粗提物(FW-1),将FW-1采用硅胶柱进一步分离得到黄酮含量较高的组分(FW-2),再采用液相色谱-质谱联用(LC-MS)系统对该组分进行分析,并测定所得FW-1、FW-2对超氧阴离子自由基(O2-·)、羟自由基(·OH)、DPPH自由基的清除能力。结果:冬枣黄酮提取物FW-1总黄酮含量为55%,FW-2中总黄酮含量为94%;FW-2的液相色谱图中的主要峰为E峰,从E峰的质谱图可以推断其为一种双黄酮类物质,相对分子质量约为790。冬枣黄酮对·OH的清除作用,随着质量浓度的增大清除率也增高,且在低质量浓度时高于VC;对O2-·的清除作用低于VC;在质量浓度为200μg/mL对DPPH自由基的清除率时可达85%以上,并且呈现剂量效应关系。结论:从冬枣中提取的黄酮类物质主要成分为双黄酮类,具有很好的抗氧化效果,并存在剂量效应关系。
This study was aimed to analyze the flavonoids from winter jujube and the antioxidant activity was also assessed. Winter Jujube was extracted with 60% ethanol and separated by macroporous resin chromatography to obtain crude flavonoids （FW-1）. FW-1 was further purified on silica gel column into FW-2. The composition and chemical structure of FW-1 and FW-2 was analyzed by LC-MS, and their radical scavenging activity against ·OH and O2 -· and DPPH radicals was measured. Results showed that total flavonoid contents in FW-1 and FW-2 were 55% and 94%, respectively. The HPLC chromatogram of FW-2 showed that the main peak was E and based on mass spectra, it was identified as bisflavonoid with a relative molecular weight of 790. Flavonoids at low concentration showed higher radical scavenging capacity against ·OH than VC but less effective in scavenging superoxide anion radical than VC. The DPPH radical scavenging rate of flavonoids at 200 μg/mL was higher than 85%, and the effect was dose-dependent. In conclusion, the main component of the flavonoids extracted from winter jujube was bis-flavonoid and it demonstrated higher antioxidant activity.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2013年第17期70-73,共4页
Food Science
基金
天津市科技支撑计划项目(11ZCKFNC01600)
