Enhancing Antioxidants Extraction from Agro-Industrial By-Products by Enzymatic Treatment

Abstract

Nowadays, agro-industrial by-products are of increasing interest as a source of antioxidant compounds. Thus, alternative green techniques to extract antioxidant compounds have been pursued. The use of enzymes to release bioactive compounds through antioxidant activity reduces the environmental impact caused by traditional extraction systems using organic solvents. A crude enzymatic extract containing carbohydrolases was produced by solid-state fermentation (SSF) of an olive pomace and brewery spent-grain combination. The crude extract was evaluated at different temperatures and pH values and its thermostability was studied. Results showed that β-glucosidase and cellulase were more stable than xylanase, particularly cellulase, which kept 91% of its activity for 72 h at 45 °C. The extract was also applied in enzymatic treatments (ET) to liberate antioxidant compounds from winery, olive mill and brewery by-products under optimal conditions for enzymatic activities. The highest antioxidant activity was found in extracts obtained after enzymatic treatment of exhausted olive pomace (EOP). Enzymatic crude extract produced by SSF was successfully applied in the extraction of antioxidant compounds from winery, olive mill and brewery by-products. Thus, integrating SSF and enzymatic technologies is a valuable approach to implement circular economy practices in the agro-food industry.

Rice Husk, Brewer’s Spent Grain, and Vine Shoot Trimmings as Raw Materials for Sustainable Enzyme Production

“…The hyphal mode of fungal growth that allows them to penetrate the spaces between substrate particles and their tolerance to lower water activities and high osmotic pressure are the main advantages in the colonization of solid substrates and the obtention of available nutrients [22]. Moreover, filamentous fungi are efficient producers of several biomolecules of interest such as enzymes, single-cell proteins, aromatics, pigments, phenolics, and other compounds [23][24][25][26][27].…”