Comparison of extraction methods and characterisation of chitin and chitosan with antimicrobial and antioxidant properties from black soldier fly (Hermetia illucens) meal

Abstract

Chitin/chitosan is a natural biopolymer that has many applications in agriculture, medicine and biotechnology. Although synthesized by different organisms, crustacean shells dominate the production. The present study focused on the extraction of chitin from an insect source using conventional and alternative extraction methods; enzyme-, microwave- and ultrasound-assisted extraction, and compared the physicochemical characteristics of the end products. The biological activities of chitosan from three sources was also investigated. The conventional extraction method from BSFM resulted in 9.7% chitin yield, while the enzyme-, microwave- and ultrasound-assisted extractions gave 42.3%, 11.4% and 13.7% chitin on dry weight basis, respectively. FTIR patterns displayed bands corresponding to the stretching and vibration of OH, NH and CO bonds, confirming the presence of α-chitin/chitosan. Chitosan samples from three different sources displayed both antioxidant and antimicrobial activity. Chitosan MW and DD both had effects on biological activities; high MW chitosan showed better antimicrobial activity lower MW chitosan.