ABSTRACT
Recently, epidermal mucus of fish has been identified as a rich biological source of various bioactive substances,particularly antibacterial peptides. This study was conducted to identify the potential of epidermal mucosa of Clariasbatrachus as a source of antibacterial material. Mucosal samples were collected from C. batrachus epidermis and extractedusing an aqueous extraction method. Antibacterial activity of the crude epidermal mucus extract was determined byusing spectrophotometric method. As a result there was antibacterial activity by the mucus extract against Escherichiacoli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853). The results of this study supports the role of mucus asa part of body immune system with antibacterial peptide as a component of innate body immune system. Hence, thesefindings can be used as one of the first steps towards the development of new class antibiotics.
ABSTRACT
Objective:To determine the antibacterial, antifungal, minimum inhibitory concentration (MIC) and the protease activity of the stingray mucus Dasyatis sephen (D. sephen) and Himantura gerrardi (H. gerrardi). Methods: Antimicrobial activity of crude aqueous, acidic and organic mucus extract was evaluated by disc diffusion method against human pathogens, MIC of the active samples were determined by spectrophotometric method and the protease activity which is responsible for the antimicrobial activity was determined by using zymogram method. Results:The crude acidic extracts of both the species showed antibacterial activity against Salmonella typhi (S. typhi), Klebsiella pneumoniae, Streptococcus aureus, Escherichia coli (E. coli), Vibrio cholerae (V. cholerae) and the acidic extracts of both the species exhibit antifungal activity against all the tested pathogens. Remaining extracts didn't show any inhibitory activity. The acidic extracts of H. gerrardi is significantly active against S. typhi, E. coli, V. cholerae, Trichophyton mentagrophytes (T. mentagrophytes), Alternaria alternaria (A. alternaria), Trichophyton rubrum (T. rubrum), Candida tropicalis (C. tropicalis) at the minimum concentration of 16μg/mL, but the acidic extract of D. sephen required 32μg/mL of protein to inhibit S.typhi, E. coli, Aspergillus niger (A. niger), penicillium sp, T. mentagrophytes, A. alternaria. Both the D. sephen and H. gerrardi shows the proteolytic activity above the molecular mass of> 66 KDa. The characterization of protease class using inhibitors showed the presence of both serine and metallo protease in the the samples. Conclusions:Protease activity present in the sting ray mucus is one of the key factor responsible for the antimicrobial activity and the results proved the role of mucus in the innate immunity.