Functionalities and antioxidant properties of protein hydrolysates from muscle of zebra blenny (Salaria basilisca) obtained with different crude protease extracts

The objective of this work was to evaluate the composition, functional properties and in vitro antioxidative activities of zebra blenny (Salaria basilisca) protein hydrolysates prepared using crude alkaline protease extracts from zebra blenny, sardinelle and smooth hound viscera. Zebra protein hydrolysates (ZPHs) obtained by treatment with crude enzyme from the same species (ZPH-Z), crude enzyme from sardinelle (ZPH-S) and crude enzyme from smooth hound (ZPH-SH) contained high protein content 85.77%, 85.51% and 85.2%, respectively. All protein hydrolysates had an excellent solubility and possessed interfacial properties, which were governed by their concentrations. The antioxidant activities of ZPHs were evaluated using various in vitro antioxidant assays: 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, reducing power, ferrous chelating activity, hydroxyl radical-scavenging activity and DNA nicking assay. All hydrolysates showed varying degrees of antioxidant activity and almost the same strongest protection against hydroxyl radical induced DNA breakage. (C) 2012 Elsevier Ltd. All rights reserved.