Paper ID 012: Extraction and Evaluation of Antimicrobial Activity of Chitosan from Fungal Species Aspergillus niger and Saccharomyces cerevisiae
Mizanul Hoque, Shaafique Chowdhury, Parisa Farzeen, Md. Masirul Afroz and Nafisa Islam*
- Abstract
- Chitosan is a biopolymer having a broad range of applications in different fields, such as medical, agricultural, water treatment etc. due to its multifunctional properties. Fungal cell wall containing chitosan can be more advantageous than other sources of chitosan (crustaceans etc.) because of its high degree of deacetylation (DD%), antimicrobial activity and homogeneity in polymer. In previous studies, sporulated Saccharomyces cerevisiae and A.niger was investigated as a potential sources of chitosan. The objective of this study is to characterize the extracted fungal chitosan and investigate their antibacterial activity. S. cerevisiae was obtained from the local market and, the effect of ammonium acetate and sodium acetate on the sporulation of yeast was observed. The S. cerevisiae was cultured in nutrition starvation condition with sodium acetate as a non-fermentable carbon source and ammonium acetate was used to investigate its action as a sporulation medium on chitosan. The sporulation was performed for 3 and 5 days to investigate the effect of cultivation duration. The data obtained from the study show the potentiality of sodium acetate to get a higher yield of chitosan (36 mg/g for 5 days’ cultivation) and sporulation inhibiting action of ammonium acetate was observed. A. niger was cultured in potato dextrose broth, then chitosan was extracted from the mycelia of A. niger through treatment with sodium hydroxide and acetic acid. The extracted fungal chitosan were characterized using FTIR (Fourier Transform Infrared Spectroscopy) and DD% obtained for chitosan from both fungal sources were between 65% to 66%. Antibacterial property for chitosan from A niger was checked on E.coli and for chitosan from S cerevisiae was checked on Staphylococcus aureus. At 1% (10g/L) concentration, A niger based fungal chitosan had a good inhibition zone, with an average diameter of 11.5 mm. At a concentration of 3 g/L, S cerevisiae chitosan had shown the maximum inhibition zone diameter of 15.38 mm. Commercially available (shrimp) chitosan was used to compare the antibacterial activity of chitosan, which gave a zone of inhibition of 9.2mm. Thus the fungal chitosan showed comparatively better antimicrobial properties against two types of bacteria.
- Presented by
- Mizanul Hoque
- Institution
- Bangladesh University of Engineering and Technology
- Keywords
- Paper No. 12, Fungal Chitosan, Antimicrobial Properties, Zone of Inhibtion




























