pH、温度对笃斯越橘花色苷粗提物抗氧化活性的影响

以大兴安岭地区野生笃斯越橘成果为原料,通过清除DPPH·能力、清除OH·能力、清除ABTS+·能力以及FRAP法测定总还原能力,对笃斯越桔粗提物在不同条件下的抗氧活性进行分析,实验结果表明,笃斯越橘花色苷提取物在pH1时表现出较好的抗氧化能力,其后随pH升高,各指标抗氧化活性有明显下降,但在清除DPPH·能力中,pH5时抗氧化活性出现明显升高,大于8后无法判断;在清除OH·能力中,pH5、10处出现峰值;清除ABTS+·能力中,pH8、10处有明显升高;在FRAP法测定总还原能力中,pH7、9处有明显峰值出现。笃斯越橘花色苷粗提物随温度的升高,抗氧化活性均有一定的下降,但在FRAP法测总还原能力中,当pH大于7后,随pH的升高,经过100℃水浴后的粗提物抗氧化活性逐渐升高,高于60℃及80℃。 

Effect of pH value and temperature on antioxidant activity of crude anthocyanins from Vaccinium vliginosum L.

In this study, anthocyanins were extracted from Daxing’anling wild Vaccinium vliginosum L. fruit. The antioxidant activities of crude anthocyanins from Vaccinium vliginosum L.were evaluated under different conditions by the abilities to scavenge ·OH, ABTS+, DPPH free radical and the total reduction capacity. The result indicated that the crude anthocyanins from Vaccinium vliginosum L. showed better antioxidant activity with the initial pH=1, then decreased with pHthe increase. DPPH radical scavenging activity was greatly improved under pH=5 and unable to be determined beyond pHexceeded 8.The activity of scavenging ·OH free radical reached a peak value in pH=5 and pH=10. ABTS+free radical scavenging activity obviously increased with the pH=8, 10. The total reduction capacity reached a maximum in pH=7, 9.The antioxidant activity of crude anthocyanins from Vaccinium vliginosum L. decreased with the increasing of temperature. However, it was found that the antioxidant activity of crude anthocyanins water bathed at 100℃ increased gradually with the increasing of pHafter the pHvalue exceeded 8. Finally, the antioxidant activity of crude anthocyanins water bathed at 100℃ were found to be more effective than water bathed at 60℃ and 80℃.