虎杖根茎中蒽醌类成分的体外抗氧化活性

摘要

采用超声波提取法用体积分数80%乙醇对虎杖(Reynoutriajaponica Houtt.)根茎中的蒽醌类成分进行粗提,并利用D101大孔吸附树脂对粗提液进行纯化.以Vc为阳性对照,采用体外动物实验研究了虎杖根茎中蒽醌类成分对小白鼠肝组织匀浆中谷胱甘肽过氧化物酶(GSH-px)活力及对H2O2诱导的MDA含量和红细胞氧化溶血的影响,并采用化学模拟体系分析了其对DPPH·自由基的清除能力、对Fe3+的还原能力以及与Fe2+的螯合能力.结果表明:虎杖根茎中蒽醌类成分含量丰富,粗提物含量达到55.86 mg·g-1,纯化后含量达到44.77 mg·g-1.质量浓度l0、20、30和40μg·mL-1的蒽醌类成分可显著增强GSH-px活力、降低由H2O2诱导产生的MDA含量,并对H2O2诱导产生的红细胞氧化溶血有较强的抑制作用;质量浓度2、4、6和8μg·mL-1的蒽醌类成分对DPPH·自由基具有良好的清除能力,质量浓度6、8、12和16μg·mL-1蒽醌类成分对Fe3+具有较强的还原能力,而质量浓度5、10、15和20μg·mL-1蒽醌类成分对Fe2+则具有很强的螯合能力.随质量浓度的提高,虎杖蒽醌类成分及阳性对照Vc的各项抗氧化活性指标均逐渐增强,呈现出明显的量效关系,且虎杖根茎中蒽醌类成分的各项抗氧化指标均优于相同质量浓度的Vc.研究结果显示:虎杖根茎中的蒽醌类成分具有较强的抗氧化活性,不仅能够直接清除过量的自由基,也可以通过增强体内的抗氧化系统以抑制自由基的产生.结合他人研究结果,对虎杖资源的开发利用提出了一些建议.%Anthraquinones were extracted crudely from rhizome of Reynoutria japonica Houtt. by ultrasonic extraction method with 80％ ethanol, and crude extract solution was purified with D101 macroporous resin. Using Vc as positive control, the effects of the anthraquinones on GSH-px activity in liver tissue homogenate of mouse and MDA content and oxidative hemolysis of red blood cells induced by H2O2 were studied by in vitro animal experiment, and its scavenging ability to DPPH· free radical, reduction ability to Fe3+ and chelating ability to Fe2+ were analyzed by chemical simulated system. The results show that anthraquinones are rich in rhizome of R. japonica, the content of crude extracts is 55.86 mg · g-1 and the content is 44.77 mg· g-1 after purified. Anthraquinones with concentrations of 10, 20, 30 and 40 μg · mL-1 can obviously enhance GSH-px activity, decrease MDA content induced by H2O2 and have strongly inhibition on oxidative hemolysis of red blood cells induced by H2O2. Anthraquinones with concentrations of 2, 4, 6 and 8 μg · mL-1 have better scavenging ability to DPPH· free radical, those with 6, 8, 12 and 16 μg · mL-1 have stronger reduction ability to Fe3+ and those with 5, 10, 15 and 20 μg · mL-1 have stronger chelating ability to Fe2+. With enhancing of concentration, the antioxidant activity indexes of anthraquinones and the positive control Vc all are enhanced gradually and appear obvious dose-effect relationship, and those of anthraquinones all are better than those of Vc in the same concentration level. It is concluded that anthraquinones from rhizome of R. japonica have strongerantioxidant activity, not only can directly remove excess free radicals, but also inhibit free radical production by enhancing antioxidant systems in vivo. Combining with other research results, some suggestions are put forward for exploitation and utilization of R. japonica resources.