利用电子顺磁波谱技术研究红参对羟自由基的清除作用

目的 探索电子顺磁波谱（electron paramagnetic resonance,EPR）技术检测红参清除自由基活性的适合产生体系,并研究红参对羟自由基（?OH）的清除作用及其物质基础。方法 采用电子顺磁共振波谱仪检测不同浓度的红参提取液对?OH的体外清除作用,并用液质联用技术（LC-MS）分析红参中的主要皂苷成分,然后研究这些人参皂苷成分对?OH的清除作用。结果 确定了羟自由基的生成体系为：Fe²⁺ 0.1 mmol?L^-1、H₂O₂ 500 mmol?L^-1、DMPO 225 mmol?L^-1;不同浓度的红参提取液对?OH具有明显的清除作用,且其清除?OH的效力与浓度成正相关;LC-MS分析显示该红参提取液中主要含有Rh1、Rf、Rb3、F1、F2、Rg3、Rg5等成分,其中人参皂苷Rg5的清除自由基活性最强。结论 本研究建立了用EPR技术研究红参清除自由基活性的适合产生体系,红参具有明显的清除?OH的能力,且人参皂苷Rg5是其清除自由基的活性成分之一,确定了红参抗自由基的主要物质基础,为红参及人参皂苷Rg5的开发、应用提供了科学依据和理论基础。

Exploring the Substances of Scavenging Hydroxyl Radical in Red Ginseng by EPR Determination

Objective To establish a suitable free radicals generation system for exploring the effects of scavenging free radical activity of red ginseng by electron paramagnetic spectroscopy (EPR) technology, and to study the scavenging effect of red ginseng on hydroxyl radical (?OH) and find the active substances in ginseng.Methods The scavenging effects of red ginseng extract in different concentrations hydroxyl radical in vitro were detected by EPR. Then the identified ginsenosides in red ginseng screened by the LC-MS method were also analyzed by EPR.Results The established hydroxyl radical generation system was as following: Fe²⁺ 0.1 mmol?L^-1, H₂O₂ 500 mmol?L^-1, DMPO 225 mmol?L^-1. Red ginseng extracts have obvious scavenging effect on?OH, and the scavenging effect were raised with the concentrations of red ginseng. LC-MS analysis showed that the red ginseng extract mainly contained Rb1, Rf, Rb3, F1, F2, Rg3, Rg5 and other components. Ginsenoside Rg5 showed the strongest scavenging activity among these components.Conclusion This study established a suitable free radicals generation system for the study of scavenging effect of red ginseng on hydroxyl radical by EPR determination. Red ginseng could scavenge ?OH obviously, and ginsenoside Rg5 is one of the active components for scavenging free radicals. It provides scientific and theoretical basis for the development and application of ginsenoside Rg5.