Evaluation of antioxidant and ‎antimicrobial properties of hydrolyzed ‎protein of Saurida tumbil

Todays, with the clarifying of the toxicity and side effects of synthetic preservatives, consumers are looking for natural compounds with anti-oxidant and antimicrobial effects. In the present study, lizardfish (Saurida tumbil) muscle was hydrolyzed by Alcalase at two concentrations of 2 and 4% and two times of 90 and 180 min. Then the antioxidant activity of fish protein hydrolysates (FPH) was evaluated by measuring DPPH, ABTS and OH free radical scavenging activity, and reducing power and ferrous ion-chelating assays. Antimicrobial activity was determined by disc diffusion and mic test. Alcalase enzymes hydrolyzed proteins showed remarkable activity in removing DPPH (37.92%), ABTS (77.34%) and hydroxyl (21.79%), as well as ferrous ion (26.95%) and poor activity in ion ferric degradation (Optical absorption of 0.001 ± 0.00 at a wavelength of 700). In the present study, the most inhibitory activity of DPPH and OH radicals was observed by hydrolyzed samples with 4% enzyme for 180 minutes. The most protein recovery yield was observed by the above sample. FPH showed no antibacterial activity against the studied bacterial strains. FPH of lizard fish with potential antioxidant activity can be recommended as an inexpensive antioxidant for use in the food industry, functional foods and animal feed.