Evaluation of Antibacterial and Antifungal Activity of Chitosan in Integument of Cockroaches

Introduction: Due to drug resistance and toxic side effects observed following administration of many antibacterial drugs, novel strategies are highly needed for treatment of bacterial diseases. Chitosan, as an important immune system stimulator, is found in cockroaches that are living in contaminated sites. The aim of this study was to extract the chitosan from nymph and adult stage of both Blattella germanica and Periplaneta americana and to evaluate its antibacterial and antifungal activities. Methods: The mature form of B. germanica and the nymph and adult forms of P. americana were killed by CO2 gas, and washed and dried at 60ºC. Then, they were mechanically ground in a mixer and passed through 20 mesh size. Finally, chitosan was extracted from shrimp processing discards. Chitosan was dissolved in lactic acid 1% and its effects against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Vibrio cholerae, methicillinresistant S. aureus, Candida albicans, and Aspergillus were evaluated. Results: Chitosan extracted from cockroaches showed antibacterial effects on grampositive bacteria especially S. aureus and E. coli. However, it had no impact on fungi. Conclusion: The findings of the current study revealed that chitosan had excellent antibacterial activities.