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BioMed Research International
Volume 2013, Article ID 408491, 11 pages
http://dx.doi.org/10.1155/2013/408491
Research Article

Fractionation and Purification of Bioactive Compounds Obtained from a Brewery Waste Stream

1Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Pharmacy, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
2GAIKER Technological Centre, 48170 Zamudio, Spain
3Department of Chemical Engineering, Industrial Engineering School, University of Vigo, 36310 Vigo, Spain

Received 7 February 2013; Accepted 28 March 2013

Academic Editor: Ana Moldes

Copyright © 2013 Letricia Barbosa-Pereira et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

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.