白茶中茶多酚提取工艺及抗氧化活性的研究

Studies on Extraction Technology and Antioxidant Activity of Tea Polyphenols from White Tea

采用水提法研究白茶中茶多酚的提取工艺及其抗氧化活性。先分别研究浸提时间、浸提温度和液料比3个单因素对白茶中茶多酚提取率的影响,然后在单因素试验的基础上以响应面分析优化提取工艺条件;以白茶中茶多酚的总抗氧化能力、清除DPPH自由基和清除·OH自由基能力来评价其抗氧化活性。结果表明:适宜的工艺条件是:时间2.5 h,温度60℃,液料比40 m L/g。在该条件下白茶中茶多酚的提取率为5.65%。白茶中茶多酚具有很强的抗氧化能力,对DPPH、·OH有清除能力,自由基的IC50为0.181,6.20μg/m L。

The extraction technology and antioxidant activity of white tea polyphenols using water extraction were studied in this paper. The effects of extraction time, extraction temperature and liquid-solid ratio on extraction rate of tea polyphenols were investigated by water extraction. Based on single factor experiments, Response Surface Methodology was used to optimize the extraction conditions. The antioxidant activity of tea polyphenols were evaluated using total antioxi- dant capacity and clear DPPH and ·OH radical ability. Results showed that the optimum process parameters are extrac- tion time is 2.5 h, extraction temperature is 60 %, liquid-solid ratio is 40：1. Under this conditions, extraction rate of white tea polyphenols is 5,65%. The white tea polyphenols has an obvious antioxidant activity, the IC_50 values of DPPH and .OH scavenging abilities was 0.181 μg/mL and 6.20 μg/mL respectively.