不同处理野木瓜的水提物清除DPPH自由基能力的分析

Analysis of DPPH Free Radical Scavenging Ability of Water Extracts of Chaenomeles cathayensis by Different Treatments

利用超声波、漂烫和微波处理技术分别对野木瓜鲜切片进行处理,以DPPH实际清除量为评价指标,分析不同处理的冻干样品的水提液对DPPH自由基的清除能力。结果表明,用酸性缓冲体系(pH 4.51 NaAc-HAc)来测定其水溶液对DPPH的清除作用,DPPH在浓度12~36μg/mL范围内与吸光度具有良好的线性关系,R^2=0.999 9;各处理在较优条件下微波(低火力、80 s)、漂烫(90℃、105 s)、超声波(240 W、35℃、55 min)和未处理组样品对DPPH的清除能力分别相当于VC的5.65%、5.55%、5.41%和5.00%;3种处理技术在一定程度上均可以提高样品对DPPH的清除能力,且微波组>漂烫组>超声波组。其增强效应的作用机制有待进一步研究。

Fresh-cut slices of Chaenomeles cathayensis were respectively treated by ultrasound, blanching and microwave technology. The DPPH scavenging ability of water extracts of freeze-dried samples with different treatments were analyzed using the actual removal mass of DPPH as evaluation index. The results showed that DPPH had a good linear relationship（R^2=0.999 9） with absorbance in the range of 12 μg/mL to 36 μg/mL by using the acidic buffer system（pH 4.51 NaAc-HAc） to determine the DPPH scavenging ability of water extracts of samples. According to the experimental optimization results, the DPPH scavenging abilities of microwave-treated samples（low firepower, 80 s）, blanching-treated samples（90 ℃,105 s）, ultrasound-treated samples（240 W, 35 ℃ and 55 min） and untreated groups were 5.65%, 5.55%, 5.41% and 5.00% of VC, respectively. To some extent, the DPPH scavenging abilities of samples by all the three treatments were improved, and microwave treated group blanching treated groupultrasound treated group, but the mechanism of enhancement effect of the three kinds of treatment technology on the DPPH scavenging ability needs to be further studied.