Antibacterial studies of fish mucus from two marketed air-breathing fishes - Channa striatus and Heteropneustes fossilis

Abstract

The purpose behind the current investigation was to understand the role of antibacterial activity of mucus in marketed air breathing fishes viz : against the selected human and fish pathogenic bacteria. In the current study, efforts have been made to screen the antimicrobial efficacy of the mucus harvested from two marketed air-breathing fishes namely Channa striatus and Heteropneustes fossilis. The antimicrobial effect of mucus was tested at 30ul concentration by well diffusion method against ten bacteria such as Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, Streptococcus pyogens (Gram Positive), Escherichia coli , Proteus vulgaris , Pseudomonas aeruginosa , Salmonella typhimurium and Vibrio cholera (Gram Negative) and Mycobacterium smegmatis (Acid-fast bacilli). The activity was measured in terms of zone of the inhibition in mm. Ciprofloxacin was used as a positive control. The antibacterial effect was noted in the mucus collected from both the fishes. Even though the effect of mucus was found to be lesser when compared to the antibiotic – ciprofloxacin, considerable effect against all the bacteria was noted irrespective of their type and species. Higher antibacterial zones were noted against Gram positive bacteria than Gram negative and acid fast bacilli. Maximum zonation was noted against Staphylococcus sp and Streptococcus sp (12 mm) with C.striatus mucus. Except M.smegmatis , the effect of mucus from C.striatus for presented a better activity than that of H.fossilis . The findings of the current investigation candidly revealed that the mucus of air breathing fish may be a potential source of antibacterial agent towards the management of bacterial ailments among fish and human.