Effect of extraction method on the Yield and Quality of Chitosan from Crickets (Acheta Domesticus) and Grasshoppers ( Ruspolia Differens)

Abstract

Chitin is a commonly known polymer found in a complex matrix with other biomolecules in crustaceans, fungi and widely in insect exo-skeleton. A number of research studies have been conducted to extract this next-gen material from the above sources mainly from crustaceans. This present report focusses on the extraction and characterization of chitosan from Ruspolia differens and Acheta domesticus, using chemical methods at room temperature and a cold extraction procedure. A chemical process involving deproteination and demineralization was used to extract chitin from both insect species while chitosan was prepared from the chitin by deacetylation. The processes were carried out using sodium hydroxide and hydrochloric acid as solvents at room temperature. The chitosan extracted was characterised and the results revealed that the percentage yield for chitin was 8.28% and 10.9%; chitosan was 3.89% and 4.21% for A. domesticus and R. differens respectively. For chitosan, degree of deacetylation was 37.34% and 28.13%; solubility was 56.28% and 46.24%; viscosity ratios of 1.78 and 1.39 for A. domesticus and R. differens respectively. The insects compare favourably with other sources of chitosan (Ibitoye et al., 2018) and the results of the cold extraction procedure can be maximized by optimising the extraction parameters in the procedure.