响应面优化机械化学法辅助提取茶末总黄酮工艺

Optimization of mechanochemical assisted extraction process of total flavonoids from tea dust by response surface methodology

以制茶副产物——茶末为原料,采用机械化学法辅助提取茶末总黄酮。在研究了碱助剂含量、乙醇浓度、料液比、提取次数、提取温度和溶液pH等单因素对总黄酮提取率影响的基础上,采用Box-Behnken试验设计原理和响应面分析法研究了碱助剂含量、乙醇浓度和料液比对茶末总黄酮提取率的影响,并建立该工艺的二次多项式模型。结果表明,回归模型具有高度显著性,可以对茶末总黄酮得率进行很好地分析和预测;确定了茶末总黄酮提取工艺的最佳条件为:提取3次、提取温度为50℃、溶液pH为4.0、乙醇浓度为40%、料液比1 g/53 mL、碱助剂含量6.3%,总黄酮提取率为9.08%。在此条件下,溶剂换用20%乙醇提取,总黄酮提取率最高达8.902%,而换用水提取,总黄酮的提取率也能达到7.858%。综合比较,用醇提取比水提取的提取率增加不到1.3%。因此,在实际生产中,从生产成本和可持续发展的角度,用水提取具有更大的工业生产优势。与热回流提取方法相比,机械化学辅助提取法需要的时间更少,更节约能源,提取率更高。

The mechanochemical assisted extraction was adopted to extract total flavonoids from tea dusttea by products in this paper. Based on effect of alkali additives content, ethanol concentration, materialto-solvent ratio and extraction times, extraction temperature and solution pH on the extraction efficiency of total flavonoids in the single factor experiment, the effects of alkali additives content, ethanol concentration and solid-to-solvent ratio and extraction time on the extraction efficiency of total flavonoids were investigated by the Box-Behnken experiment design principle and the response surface analysis and a quadratic polynomial model was established and validated to be highly significant and allow the prediction of the extraction efficiency of total flavonoids. The optimum conditions for the extraction of total flavonoids were 40% ethanol as the extraction solvent at a solid-to-solvent ratio of 1：53 （g/mL）, alkali agent content of 6.3%, pH of 4.0, 50 % and extracting 3 times. The extraction efficiency of total flavonoids was 9.08% under these conditions. The extraction efficiency of total flavonoids up to 8.902% and 7.858% when the solvent was 20% ethanol and distilled water, respectively. Comprehensive comparison, the extraction efficiency of total flavonoids increased less than 1.3% with alcohol than water. Therefore, the extraction with water as the extraction solvent is more industrial production advantage in the actual production from the raw material costs and the sustainable development. The mechanochemical assisted extraction have less time, more saving energy and higher extraction efficiency than hot reflux extraction.