Chemical and antibacterial properties of chitosan derived from Mucor spp., Rhizopus. Oryzae and Hermetia illucens

Abstract

At present, commercial chitosan is mainly produced from crustacean shell. However, there are still other potential natural sources for production of chitosan, such as fungi and insects. In this study, chemical characteristic and antibacterial activity of chitosan derived from Mucor spp., Rhizopus oryzae, and black soldier fly (Hermetia illucens) larvae were examined and compared with a commercial chitosan from shrimp. Chitosan recovery obtained from Mucor spp., R. oryzae, and H. illucens was 157.3 mg/g biomass, 133.1 mg/g biomass, 4.28 mg/g biomass, respectively. The deacetylation degree (DD) of chitosan from Mucor spp., R. oryzae, and H. illucens was 80.09%, 80.92%, and 84.18%, respectively. The values resemble the DD of chitosan from commercial shrimp, 79.14%. The results of this study showed that chemical properties in chitosan influence its antibacterial activity. The chitosan from Mucor spp., R. oryzae, and H. illucens inhibits the growth of Staphylococcus aureus with an inhibition diameter of 16.8 ± 0.4 mm, 20.9 ± 0.1 mm, and 28.5 ± 2.8 mm. In addition, the chitosan from Mucor spp., R. oryzae, and H. illucens also inhibits the growth of Escherichia coli with an inhibition diameter of 12.8 ± 0.5 mm, 14.9 ± 0.5 mm, and 25.2 ± 1.9 mm, respectively. The findings of this study clearly show that Mucor spp., R. oryzae, and H. illucens have great potential as alternative sources of bioactive material applied in the field of food and medicine.