INCDO-INOE 2000, Research Institute for Analytical Instrumentation, ICIA, 400293 Cluj-Napoca, Romania.
Molecules. 2020 Sep 14;25(18):4209. doi: 10.3390/molecules25184209.
Circular economy principles are based on the use of by-products from one operation as the raw materials in another. The aim of this work is to obtain extracts with high antioxidant capacity and resveratrol content for the superior capitalization of the biomass of leaves obtained during vineyard horticultural operations in spring. In order to obtain a high-quality extract at an industrial level, an optimal extraction process is needed. Central composite design (CCD) was used for the experiment design, which contained three independent variables: the ratio of extraction solvent to solid matter, temperature (°C) and time (minutes). The evaluation of extracts was done by measuring the total antioxidant capacity of the extracts using photo-chemiluminescent techniques, and the resveratrol content using liquid chromatography. Process optimization was done using response surface methodology (RSM). Minitab software version 17.0 was used for the design of experiments and data analysis. Regression analysis showed that the model predicts 87.5% of the variation for resveratrol and 96% for total antioxidant capacity (TAC). The temperature had the biggest influence on the extraction yield. The optimal operational conditions for the extraction method applied had the following conditions: ratio e/m 2.92; 43.23 °C and 55.4 min. A maximum value of 34,623 µg ascorbic acid equivalent (AAE) /mL total antioxidant capacity and 182.4 µg/mL resveratrol content were obtained when the optimal extraction parameters where used. The values obtained in experiments proved that by using RSM an accurate model can be obtained for extraction of leaves.
循环经济原则基于将一个操作的副产品用作另一个操作的原材料。本工作的目的是获得具有高抗氧化能力和白藜芦醇含量的提取物，以实现春季葡萄园园艺作业中获得的叶子生物质的超额资本化。为了在工业水平上获得高质量的提取物，需要优化提取工艺。采用中心组合设计（CCD）进行实验设计，其中包含三个独立变量：提取溶剂与固体物质的比例、温度（°C）和时间（分钟）。通过使用光化学发光技术测量提取物的总抗氧化能力和使用液相色谱法测量白藜芦醇含量来评估提取物。使用响应面法（RSM）进行工艺优化。Minitab 软件版本 17.0 用于实验设计和数据分析。回归分析表明，该模型对白藜芦醇的预测变异为 87.5%，对总抗氧化能力（TAC）的预测变异为 96%。温度对提取产率的影响最大。应用的提取方法的最佳操作条件如下：比例 e/m 2.92；43.23°C 和 55.4 分钟。当使用最佳提取参数时，可获得 34,623 µg 抗坏血酸当量（AAE）/mL 总抗氧化能力和 182.4 µg/mL 白藜芦醇含量的最大值。实验中获得的值证明，通过使用 RSM 可以获得准确的提取模型。
