Terrestrial insects as a promising source of chitosan and recent developments in its application for various industries.

Chitosan is a deacetylated form of chitin and increasingly important amino-polysaccharide used in many various sectors including agriculture, food, and biomedicine. However, chitosan from marine sources has several adverse effects, including allergenic components harmful to human health. Furthermore, marine resources are seasonal, and availability is limited due to dependency on environmental conditions and climate change. In addition, shell infection in crustaceans and environmental contamination make the harvesting of chitin and chitosan problematic. In recent years, chitosan from terrestrial insects has attracted considerable interest. The discoveries show insect chitosan is more advantageous compared to crustacean chitosan. In addition, we were unable to find any literature about the adverse effects of insect chitosan thus far. This review aims to reveal information regarding crustacean and terrestrial insect chitosan and recent advances in chitosan sources. Applications from specific insect orders and perspectives for further study will also be highlighted, including medical and sensing applications.