Isolation and Characterization of Chitosans from Different Fungi with Special Emphasis on Zygomycetous Dimorphic Fungus Benjaminiella poitrasii: Evaluation of Its Chitosan Nanoparticles for the Inhibition of Human Pathogenic Fungi

The cell wall chitosan was extracted from fungi belonging to different taxonomic classes, namely, Benjaminiella poitrasii (Zygomycetes, dimorphic), Hanseniaspora guilliermondii, Issatchenkia orientalis, Pichia membranifaciens, and Saccharomyces cerevisiae (Ascomycetes, yeasts), and Agaricus bisporus and Pleurotus sajor-caju (Basidiomycetes). The maximum yield of chitosan was 60.89 ± 2.30 mg/g of dry mycelial biomass of B. poitrasii. The degree of deacetylation (DDA) of chitosan extracted from different fungi, as observed with 1H NMR, was in the range of 70–93%. B. poitrasii chitosan exhibited the highest DDA (92.78%). The characteristic absorption bands were observed at 3450, 1650, 1420, 1320, and 1035 cm–1 by FTIR. Compared to chitosan from marine sources (molecular weight, MW, 585 kDa), fungal chitosans showed lower MW (6.21–46.33 kDa). Further, to improve the efficacy of B. poitrasii chitosan (Bp), nanoparticles (Np) were synthesized using the ionic gelation method and characterized by dynamic light scattering (DLS). For yeast and hyphal chitosan nanoparticles (BpYCNp and BpHCNp), the average particle size was