Extraction of Chitin and Chitosan from the Exoskeleton of the Cockroach (Periplaneta americana L.)

Chitin and chitosan from the exoskeleton of the cockroach (Periplaneta americana L.) were extracted using the following chemical treatment with an acid and alkali: For chitin extraction, 2 N HCl and 1.25 N NaOH solutions were used to achieve demineralization and deproteinization, respectively. To obtain chitosan, chitin particles from cockroaches were boiled at different NaOH concentrations and temperatures. The relative average yields of chitin and chitosan from cockroaches were 3.36% and 2.08%, respectively, on a fresh-weight basis. The relative average yield of chitin and chitosan was 12.17% and 7.28%, respectively, on a dry-weight basis. The deacetylation percentage of chitosan from exoskeletons of cockroaches were 90.03%, 91.86%, and 89.4% in Procedures B, C, and D, respectively. The viscosity of chitosan extracted from exoskeletons in Procedures B, C, and D was 48.0, 69.6, and 36.0 cP, respectively. The molecular weight of the obtained chitosan was 230,300 Da in Procedure C and 212,100 Da in Procedure D. Our results indicate that exoskeletons of cockroaches may serve as a source of chitin and chitosan for livestock and cultured fish industry and for preparation of elicitors for improvement of resistance to phytopathogens in agriculture.