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Chitin is a homopolymer of N-acetly-D-glucosamine (Glc-NAc) residue linked by β-1-4 bonds and is the most widespread renewable natural biopolymer. Chitosan is deacetylated derivative of chitin and is an amino polysaccharide. In the present study, an effort is made to extract the chitin and chitosan of low molecular weight from fungi. The standard fungal strains Trichoderma reesei (NCIM 1052) and Aspergillus awamori (NCIM 861) were selected for the extensive study. The two way method of extraction using dilute sulfuric acid was used to extract chitin and chitosan from the cell wall of the fungi. The yield of chitin from Trichoderma reesei and Aspergillus awamori was 903 mg/L and 1010 mg/L respectively. Similarly, the yield of chitosan from Trichoderma reesei and Aspergillus awamori was 130 mg/L and 136 mg/L respectively. Profiling of growth parameters such as dry cell biomass, utilization of carbon source (dextrose) and pH was studied. FTIR of chitin and chitosan was evaluated for wavelength bands with respect to the–OH,-NH, C= O,-CN groups for the identification of material nature.

Using FTIR data, molecular properties of chitin and chitosan such as degree of deacetylation (DD%), molecular weight and viscosity were evaluated. The degree of deacetylation of chitin and chitosan extracted from Trichoderma reesei and Aspergillus awamori was 16.76%, 17.12%, 69.69% and 72.45% respectively indicating maximum conversion of chitin to chitosan. Molecular weights of chitin and chitosan from the fungi were 10.35× 106 Da, 4.23× 106 Da and 8.5× 105 Da, 3.3× 105 Da respectively. The specific viscosities measured were 7.01 cP, 5.06 cP …