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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
India is endowed with an extensive network of fisheries resources; a long coast line of 1100 km along the Arabian Sea, supports a wide range of fish species with economic value and nutritional importance. Approximately 180 species of fish are found in fresh waters of India, majority of which are edible Antimicrobial proteins and peptides had been found from a wide variety of organisms in the last few years. These molecules have attracted much research interest because of their biochemical diversity, broad specificity on anti-viral, anti-bacterial, anti-fungi, anti-protozoan parasites, anti-tumoural, and wound-healing effects. Antimicrobial proteins and peptides play key roles in innate immunity. They interact directly with bacteria and kill them. The present study was performed in order to isolate and purify the protein from skin and muscles homogenate of Labeo rohita (Rohu). Different studies are already performed which showed that bacteria and virus have caused high mortality in Labeo rohita cultures, but the endogenous antimicrobial peptides and proteins have not been explored till yet or less evidences are reported. As per the results observed, an antimicrobial component was obtained from the skin and muscles homogenate of L. rohita. It was observed that when the skin and muscles homogenate was digested with trypsin (proteolytic enzyme), its antimicrobial activity was lost, which confirmed that the antimicrobial component is a protein. The antimicrobial protein was further purified from the skin and muscles homogenate of Labeo rohita by successive ion-exchange and gel filtration chromatography. The protein isolated was demonstrated to be single protein band by SDS-PAGE, with the apparent molecular weight of 46 KDa. The crude protein content in the mixed homogenate of the fish was found to be 20.5%. Although different feed content may also vary the nutritional significance of different biomolecules in the fish which is also another part of study. The protein fraction isolated was evaluated for antimicrobial activity. The protein fraction exhibited antimicrobial activity both for the Gram-positive bacteria, Staphylococcus aureus, Micrococcus luteus and Bacillus subtilis, and for the Gram-negative bacteria, Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio fluvialis, Pasteurella multocida, Aeromonas hydrophila, Escherichia coli, and Pseudomonas aeruginosa. Except A. hydrophila, P. aeruginosa, and E. coli (MIC>19 mol/L), most of the tested Gram-negative bacteria were sensitive to protein fraction (MIC<18 mol/L). Interestingly, the protein fraction showed potent antimicrobial activity against Gram-positive bacteria, S. aureus (MIC 5-10 mol/L) but comparatively weak antimicrobial activity against M. luteus and B. subtilis. The study thus suggests the presence of antimicrobial amino acids in the protein fraction which are needed to be isolated and characterization for further studies.