ANTIOXIDANT ACTIVITY OF CHIA (Salvia hispanica L.) PROTEIN FRACTION HYDROLYZED WITH ALCALASE AND FLAVOURZYME.

Abstract

The variety of proteins of plant origin that can be hydrolyzed to produce bioactive proteins is ample. However, from a sustainable perspective, a feasible and economic way to produce them is using their byproducts. The objective of this study was to obtain protein enzymatic hydrolysates from a byproduct of chia (Salvia hispanica L.) oil extraction. The experimental design was completely randomized in a two-factor factorial arrangement (enzyme and time). The antioxidant activity was evaluated in a food matrix. The hydrolysis reactions were performed under controlled conditions of pH, temperature and time with the enzymes Alcalase® (ALC) and Flavourzyme® (FLA) separately and in a sequential system. The hydrolysis degree (HD) was estimated with the determination of free amino groups (FAG). The phenolic compounds were defined with the Folin-Ciocalteu reaction. The antioxidant activity was obtained with the ABTS and DPPH methods. The HD depended on the reaction time and on the nature of the enzyme preparation. FLA was more effective in the breakage of peptide bonds (25.44 %, 30 min) than ALC (19.88 %, 150 min). The antioxidant activity with FLA was lower than with ALC. The increase in HD (37.16 %) during the digestion with the sequential system ALC-FLA in 90 min showed higher ABTS antioxidant activity (12.56 mmol L-1 mg-1 protein) and higher DPPH radical sweep (77.47 %), compared to the individual enzymatic treatments. This result was probably due to the production of peptides of low molecular weight and from the synergetic effect of phenolic compounds. The incorporation of chia protein hydrolysates increased the antioxidant potential of the food matrix, could favor the development of a functional food, and contribute to the revaluation of the byproducts derived from agroindustry