Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Pharmacy, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Biomed Res Int. 2013;2013:408491. doi: 10.1155/2013/408491. Epub 2013 May 12.
The brewery industry generates waste that could be used to yield a natural extract containing bioactive phenolic compounds. We compared two methods of purifying the crude extract-solid-phase extraction (SPE) and supercritical fluid extraction (SFE)--with the aim of improving the quality of the final extract for potential use as safe food additive, functional food ingredient, or nutraceutical. The predominant fractions yielded by SPE were the most active, and the fraction eluted with 30% (v/v) of methanol displayed the highest antioxidant activity (0.20 g L(-1)), similar to that of BHA. The most active fraction yielded by SFE (EC50 of 0.23 g L(-1)) was obtained under the following conditions: temperature 40 °C, pressure 140 bar, extraction time 30 minutes, ethanol (6%) as a modifier, and modifier flow 0.2 mL min(-1). Finally, we found that SFE is the most suitable procedure for purifying the crude extracts and improves the organoleptic characteristics of the product: the final extract was odourless, did not contain solvent residues, and was not strongly coloured. Therefore, natural extracts obtained from the residual stream and purified by SFE can be used as natural antioxidants with potential applications in the food, cosmetic, and pharmaceutical industries.
啤酒厂产生的废物可以用来提取含有生物活性酚类化合物的天然提取物。我们比较了两种纯化粗提取物的方法——固相萃取（SPE）和超临界流体萃取（SFE）——旨在提高最终提取物的质量，使其有可能用作安全的食品添加剂、功能性食品成分或营养保健品。SPE 产生的主要馏分最活跃，用 30%（v/v）甲醇洗脱的馏分显示出最高的抗氧化活性（0.20 g L(-1)），与 BHA 相似。SFE 产生的最活跃馏分（EC50 为 0.23 g L(-1)）的条件为：温度 40°C，压力 140 巴，萃取时间 30 分钟，乙醇（6%）为改性剂，改性剂流量 0.2 mL min(-1)。最后，我们发现 SFE 是纯化粗提取物最适宜的方法，并改善了产品的感官特性：最终提取物无气味，不含溶剂残留，且颜色不深。因此，从残余物流中获得的天然提取物，并通过 SFE 纯化后，可用作天然抗氧化剂，具有在食品、化妆品和制药行业中的潜在应用。
