Different concentrations of chitosan affect the growth and development of Aspergillus carbonarius and Fusarium sulphureum

Abstract:

[Background] Chitosan (CTS) is a polysaccharide ubiquitous in crustaceans. CTS has broad-spectrum antifungal activities, while whether CTS affects the growth and development of Aspergillus carbonarius and Fusarium sulphureum remains unknown. [Objective] To determine the effects of different concentrations of CTS on the growth and development of A. carbonarius and F. sulphureum. [Methods] The colony diameters, biomass, and mycelial dry weights of the two fungal species cultured in the potato dextrose agar (PDA) media with different concentrations of CTS were determined. The inhibitory effects of CTS on the two fungal species were evaluated by comparison of the sporulation, spore germination, and germ tube length. [Results] CTS treatment significantly altered the colony morphology of both fungal species. Higher concentrations of CTS resulted in more obvious colony shrinkage and deformation. CTS reduced colony diameter, mycelial dry weight, and mycelial biomass of both fungal species in a concentration-dependent manner, with stronger inhibitory effect on F. sulphureum. Similarly, CTS inhibited the sporulation, spore germination, and germ tube elongation in a concentration-dependent manner, which was more significant on F. sulphureum. The EC₅₀ values of CTS on A. carbonarius and F. sulphureum were 0.12 mg/mL and 0.075 mg/mL, respectively. [Conclusion] CTS inhibited the growth and development of A. carbonarius and F. sulphureum in a concentration-dependent manner, with stronger effect on F. sulphureum.