诃子粗提物及不同极性部位抑制低密度脂蛋白氧化修饰的研究

Anti-low density lipoprotein oxidation of the crude extract and different fractions of Terminalia chebuLa Retz

为了研究诃子抑制低密度脂蛋(Low density lipoprotein,LDL)氧化修饰活性,采用Cu2+体外诱导LDL氧化,以硫代巴比妥酸反应物(thiobarbituric acid reactive substance,TBARS)含量为指标评价氧化修饰程度。运用生物活性追踪法确定诃子抗LDL氧化修饰有效部位,并对其抗LDL氧化修饰活性进行了研究。结果表明,不同浓度诃子粗提物(0.5、0.9、2.7mg/mL)抗LDL修饰抑制率分别为64.31%、77.22%和82.66%。相同浓度(0.5mg/mL)的不同极性部位中,乙酸乙酯相抗LDL氧化修饰能力显著高于其他3个极性部位(p<0.05),为有效部位。不同浓度有效部位(0.5、0.9、2.7mg/mL)抗LDL修饰的抑制率分别达73.19%、81.85%和86.29%。有效部位能明显延长LDL氧化反应潜伏期并能延缓和降低LDL氧化修饰程度。诃子抗LDL氧化修饰与其所含的总黄酮和总多酚有关。结果显示,诃子具有很强的抗LDL氧化修饰能力,为后期开发抗LDL氧化及抗动脉粥样硬化功能食品奠定基础。

The property of anti-low density lipoprotein oxidation of Terminalia chebuLa Retz（TCR） was studied in vitro Cu 2 ＋ induction on LDL. The effective fraction of TCR on the anti -LDL oxidation was determined by thiobarbituric acid reactive substance（TBARS） guided method. All these results were showed as follows：The inhibition rates of the TCR crude extracts on LDL oxidation were 64.31%,77.22% and 82.66%,respectively. The ethyl acetate fraction possessed the most strong inhibition activity on LDL than other three fractions（p＆lt;0.05）, and was the effective fraction with the same concentrations. The inhibition rates of the effective fraction（0.5,0.9 and 2.7mg/mL） were 73.19% ,81.85% and 86.29% ,respectively. The incubation periods of oxidation were delayed and degrees of oxidation were reduced by the effective fraction with different concentrations. The property of anti-low density lipoprotein oxidation of TCR was related to the total flavonoids and polyphenols in it. This study showed that TCR possessed strong anti-LDL oxidation activity and lay the foundation for further exploration on anti-atherosclerotic functional foods.