ISOLATION, CHARACTERIZATION, AND DETERMINATION OF ANTIOXIDATIVE PROPERTIES OF PROTEIN EXTRACTED FROM ROHU (LABEO ROHITA) FISH SKIN

Objective: Isolation, characterization and analysis of antioxidant activity of protein extracted from Labeo rohita skin. Methods: The present work aimed to characterize protein isolated from Indian major carp L. rohita skin. Protein isolation was carried out by the salting-out method and the protein content was estimated with bovine serum albumin. Isolated protein was subjected to Fourier-transform infrared analyzer to identify the presence of –NH3 group to be claimed as protein. It was also subjected to high-performance liquid chromatography (HPLC) analyzer and run against standard collagen (Sigma), the molecular weight of the protein was determined through mass spectroscopy (MS) to know the protein structure more precisely the protein isolate was studied under a scanning electron microscope (SEM). Antioxidative activity of the crude protein sample was studied through 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant potential (FRAP) assay, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay. Results: The protein isolated was 23% of the dry weight of fish skin. In HPLC analysis, the isolated protein gives peaks that are similar to that of standard collagen, and in MS, its molecular weight was near about 300 kDa, which is the molecular weight of collagen type 1. The SEM image shows a crystal structure of protein isolates. Results of antioxidative property show that fish skin protein isolates have good antioxidative activity also. Conclusion: The isolated protein was collagen and it can be used as a replacer of the renowned market available collagen.