蓝莓叶多酚减压提取工艺优化

采用减压提取蓝莓叶多酚,在单因素基础上采用正交实验对pH、提取时间、料液比、粒度进行优化,得到最佳提取条件为:真空度-0.07MPa,乙醇浓度60%,pH3.5,提取时间60min,料液比1∶50,物料粒度80～100目,在此条件下多酚提取率为81.47%,多酚纯度为45.32%,其中多酚纯度比常压提取高6.57%。采用ORAC法、TEAC法、DPPH法、亚硝酸盐法对蓝莓叶多酚抗氧化能力进行评价,结果表明:蓝莓叶多酚有很强的抗氧化能力,减压提取的蓝莓叶多酚比常压提取的蓝莓叶多酚具有更强的抗氧化能力。

Optimization of vacuum extraction of polyphenols from blueberry leaves

Polyphenols was extracted from blueberry leaves by vacuum extraction process. On the basis of single-factor test,orthogonal design was used on the optimum extracting process to determine the effect of pH,extraction times,solid-liquid ratio,and granularity with the productivity of polyphenols as maker. The optimal parameters of vacuum extraction process was as follows∶-0.07MPa vacuum,ethanol concentration 60%,pH 3.5,extraction time 60min,solid-liquid ratio 1∶50,granularity 80～100 mesh. Under the optimized condition,the productivity and purity of polyphenols was 45.32%,81.47% respectively,among them,the purity of polyphenols was 6.57% higher than that from normal pressure extraction process. The antioxidant capacity of polyphenols was evaluated by ORAC assay,TEAC assay,DPPH assay and nitrite assay. Statistics showed that polyphenols from blueberry had strong antioxidant activity. Furthermore,when compared with normal pressure extraction process,polyphenols from vacuum extraction process had stronger antioxidant capacity.