人参皂苷Re与精氨酸美拉德反应产物的抗氧化性研究

摘要

为了研究人参皂苷Re与精氨酸美拉德反应产物的抗氧化活性,采用人参皂苷Re与精氨酸在100℃反应4h制备得到美拉德反应产物.HPLC分析产物中人参皂苷Re的结构变化,考察了反应体系的褐变程度,并测试了体系的总多酚含量、Cu2+螯合能力、DPPH自由基清除能力,以及对Cu2+诱导的HepG2细胞的抗氧化作用.结果显示,美拉德反应产物中人参皂苷Re部分转化为Rg2、Rg6和F4,美拉德反应产物的褐变程度、总多酚含量显著增加,与对照相比,美拉德反应产物对Cu2螯合能力和DPPH自由基清除能力显著提高,100～ 300 μg/mL美拉德反应产物对Cu2诱导的HepG2细胞氧化应激具有显著的抑制能力.%The aim of the present study was to evaluate the important role of ginsenoside Re-arginine Maillard reaction products (MRPs) in the free radical scavenging and against Cu2 +-induced oxidative stress in HepG2 cells.Ginsenoside Re with arginine was heated at 100 ℃ for 4 h to prepare the MRPs.The MRPs was analyzed by HPLC,the browning level was assayed at 420 nm,total phenol content was assayed by the Folin-Ciocalteu method and the result was illustrated as milligrams of GAE per gram of each sample tested.The change of Cu2+ chelating activities and the scavenging effect on DPPH radical were also evaluated.Meanwhile,the antioxidant ability was also assayed in HepG2 cells by using the Cu2+-induced oxidative stress model.The results indicate that the ginsenoside Re is transformed into less-polar ginsenosides such as Rg2,Rg6 and F4 during Maillard reaction,and the glucose molecule at carbon-20 is separated,the browning level and the total phenol increase obviously,the Cu2+ chelating activity and DPPH radical scavenging activity are enhanced significantly.Comparing to the control,there is a 3.16-fold increase of oxidative stress of HepG2 cells under the influence of Cu2 +.The oxidative stress induced by Cu2 + is only marginally inhibited by the treatment of ginsenoside Re or Re-arginine mixture (not significant,p ＞ 0.05) but significantly reduced by the treatment with Re-arginine MRPs in the concentration range of 100 to 300 μg/mL.Because of their high cell-membrane permeability,the ginsenoside Rearginine MRPs increase the free radical-scavenging acivity in HepG2 cells,showing cellular antioxidant activity against Cu2+-induced oxidative stress higher than that of Re.