Antibacterial Activity of Different Extracts of Prawn Shell (Macrobrachium nipponense) Against Human Bacterial Pathogens

Aims: Bioactive compounds existing in crustacean shells have the potential to inhibit the growth of some pathogenic microorganism. The purpose of this study is to evaluate the antibacterial effects of different extracts of prawn shells (Macrobrachium nipponense) on some human pathogenic bacteria. Materials and Methods: Sampling (prawn) was conducted in summer 2014 from Anzali wetland in southern coast of Caspian Sea. Then, the hydroalcoholic, methanolic, and acetone extracts of prawn shells were applied for this purpose. Two Gram‑positive (Bacillus subtilis Staphylococcus aureus) and three Gram‑negative (Klebsiella pneumoniae, Vibrio cholerae, and Escherichia coli) were used as test organisms. The antibacterial activity was determined by paper disk diffusion. Results: The prawn shell extracts showed activity against pathogenic bacteria. The highest antibacterial activities were measured in B. subtilis, S. aureus, and V. cholerae with the zone of inhibition being 12.12 ± 0.32 mm, 12.51 ± 0.14 mm, and 12.35 ± 0.27 mm, respectively. Among all the strains, S. aureus exhibits a significant zone of inhibition against all extracts (P < 0.05). Conclusion: The findings of this research showed that different prawn shell extracts, particularly hydroalcoholic, have bactericidal effect on B. subtilis, S. aureus, and V. cholerae species.