The main goal of this study was to valorize Thymus serpyllum L., the by-product of filter-tea production, for extraction of polyphenols with high antioxidant capacity by ultrasound-assisted extraction (UAE). Herbal dust is formed during the preparation of raw material for tea packaging, it is separated as a fraction which is unusable in the tea industry and distinguished as an industrial waste. In order to optimize the process, three levels, three variables, face-centered central composite experimental design within the response surface methodology (RSM) was applied. Temperature (50, 65 and 80 °C), extraction time (40, 55 and 70 min) and ethanol concentration (45, 60 and 75%) were used as independent variables. Selected responses were total extraction yield (Y) and total phenols yield (TP), as well as antioxidant activity parameters obtained by DPPH, ABTS and FRAP assays. Results were fitted to a second-order polynomial model and goodness of fit was determined by regression analysis and analysis of variance (ANOVA). Good accordance between experimental and predicted values was achieved, which suggested that obtained models could be used for multi-response optimization in order to maximize yields of target responses and improve antioxidant potential of T. serpyllum liquid extracts. Furthermore, UAE provided advantages comparing to conventional solid-liquid extraction in terms of antioxidant activity and total extraction and total phenols yield. Therefore, it could be concluded that T. serpyllum herbal dust could be used as raw material for production of antioxidant-rich extracts.

本研究的主要目标是提高百里香L.，滤茶生产的副产品，用于通过超声辅助提取 (UAE) 提取具有高抗氧化能力的多酚。草本粉尘是在茶叶包装原料的制备过程中形成的，它被分离为茶工业中无法使用的部分，并被视为工业废物。为了优化该过程，应用响应面方法 (RSM) 内的三个水平、三个变量、以面为中心的中心复合实验设计。温度（50、65 和 80 °C）、提取时间（40、55 和 70 分钟）和乙醇浓度（45、60 和 75%）用作自变量。选定的反应是总提取产量 (Y) 和总酚产量 (TP)，以及通过 DPPH、ABTS 和 FRAP 测定获得的抗氧化活性参数。结果拟合到二阶多项式模型，拟合优度通过回归分析和方差分析 (ANOVA) 确定。实验值和预测值之间取得了很好的一致性，这表明所获得的模型可用于多响应优化，以最大限度地提高目标响应的产量并提高抗氧化潜力。T. serpyllum液体提取物。此外，在抗氧化活性、总提取量和总酚产量方面，UAE 与传统的固液提取相比具有优势。因此，可以得出结论，T. serpyllum草本粉尘可用作生产富含抗氧化剂的提取物的原料。