萝果壳蛋白提取工艺的优化及其抗氧化活性研究

采用碱提酸沉法对萝藦果壳蛋白的提取条件进行研究,以蛋白提取率为指标,在单因素实验的基础上,进行正交实验。结果表明在料液比1∶20(g/m L)、提取液p H11.5、浸提温度60℃、提取时间1.0 h的条件下,蛋白提取率最高,为89.18%。并对最佳条件下提取的蛋白进行体外抗氧化实验。结果显示,提取蛋白对DPPH·、·OH的清除率分别为79.45%(8 mg/m L)、55.35%(8 mg/m L),且清除DPPH·、·OH的半抑制浓度(IC50)分别为4.19、3.30 mg/m L,并具有还原能力,但弱于VC。 

Optimization of extraction process of protein from Metaplexis Japonica Makino nutshell and evaluation of its antioxidative activity

The theory of alkali extraction and acid precipitation was employed to optimize the extraction conditions of protein from Metastasis Japonica Makino nutshell ( MJNP) , and protein extraction rate as index, by means of the single factor experiments and orthogonal experiment.The results showed that the optimum conditions were as follows: ratio of solid to liquid of1∶ 20 ( g/m L) , solution p H11.5, temperature of 60 ℃ and extraction time of 1.0 h, and the average extraction yield was 89.18%.Antioxidant experiments were primarily evaluated, under the condition of the optimized process, the protein had the scavenging capacity against DPPH· and ·OH with the scavenging rate of 79.45% ( 8 mg/m L) and 55.35% ( 8 mg/m L) , the IC50 value of DPPH·, and ·OH was 4.19 mg/m L and 3.30 mg/m L, respectively. Moreover, the protein extracted from Metastasis Japonica Makino nutshell possessed weaker reducing power than VC.