蓝莓花青素的抗氧化活性对比及其稳定性分析

本文研究不同提取工艺对蓝莓花青素抗氧化活性的影响,以及对微波波辅助提取得到的蓝莓花青素的稳定性进行了分析。通过1,1-二苯基-2-苦肼基(DPPH·)、羟基自由基(·OH)、超氧自由基(O2-·)等体外抗氧化实验评价不同提取工艺所提取的蓝莓花青素抗氧化活性,并分析光照、pH、温度、葡萄糖以及有机酸对蓝莓花青素保存率的影响。结果显示,乙醇浸取法、丙酮浸取法和微波辅助提取法的蓝莓花青素的得率分别为4.46%、4.41%和4.92%。蓝莓花青素的体外抗氧化活性在0.25~4.0 mg/mL范围内有浓度依赖性,微波辅助提取法获得的蓝莓花青素浓度为4.0 mg/mL时,DPPH·清除率、·OH清除率和O2-·清除率分别为86.59%、56.85%和88.65%,均显著高于乙醇浸提法、丙酮浸提法(p<0.05)。蓝莓花青素在强光、碱性、高温及抗坏血酸存在的环境下较为不稳定,而葡萄糖和柠檬酸则对蓝莓花青素的稳定性有一定的保护作用。

Antioxidant Activity Comparison and Stability Analysis of Anthocyanin from Blueberry

The effects of different extraction processes on the antioxidant properties of blueberry anthocyanin and the stability analysis of microwave-assisted extraction of blueberry anthocyanin were investigated. The antioxidant activities of blueberry anthocyanin extracted by different extraction processes were evaluated by 1,1-diphenyl-2-bitter hydrazine(DPPH·), hydroxyl free radical(· OH), superoxide free radical(O2-·). The stability of blueberry anthocyanin obtained by microwave-assisted extraction was tested, and the light, pH, temperature, glucose and organic acid were detected to analyze the effect of anthocyanin preservation rate of blueberry. The results showed that the yield rate of blueberry anthocyanin extracted by ethanol, acetone and microwave-assisted were 4.46%, 4.41% and 4.92%, respectively. The antioxidant activity of blueberry anthocyanin in vitro was concentration dependent in the range of 0.25~4.0 mg/mL. When the concentration of blueberry anthocyanin extracted by microwave-assisted was 4.0 mg/mL, the clearance rate of DPPH··OH and O2-· were 86.59%, 56.85% and 88.65%, respectively, which were significantly higher than that by ethanol extraction and acetone extraction(p<0.05). Blueberry anthocyanin was unstable in the environment of strong light, alkaline, high temperature and ascorbic acid, but glucose and citric acid could protect the stability of blueberry anthocyanin.