Synthesis of chitosan nanoparticles from Tasar silkworm, Antheraea mylitta pupae and its antioxidant efficacy and antibacterial activity against fish pathogens

Aim: To synthesize and characterize chitosan nanoparticles (CNPs) from the pupae of tasar silkworm, Antheraea mylitta. The antioxidant and antibacterial activities of CNPs against different strains of selected bacterial fish pathogens were also evaluated. Methodology: CNPs were prepared using sodium tripolyphosphate anions. Characterization of nanoparticles was done by FTIR, Zeta potential analysis and Particle size distribution analysis. The antibacterial activity of chitosan and CNPs against Aeromonas hydrophila (ATCC-7966), Escherichia coli (ATCC-25922), and Staphylococcus aureus (ATCC-25923) was evaluated by disc diffusion method. Results: CNPs inhibited the growth of selected bacteria and the maximum zone of inhibition (14 mm) was observed against E. coli and A. hydrophila. Chitosan and CNPs had free radical scavenging effects on hydrogen peroxide (H2O2) and 2,2-diphenyl-1-picrylhydrazyl (DPPH). Interpretation: CNPs obtained from silkworm pupae have potential antibacterial as well as antioxidant activities and can be incorporated in aquafeed to prevent fish diseases. Key words: Aeromonas hydrophila, Antheraea mylitta, Antibacterial activity, Antioxidant activity, Chitosan nanoparticles