摘要
Two methods were used to produce chitosan by deacetylation of chitin which was extracted from Agaricus bisporus stipes.The first one gives chitosan 1 with low yield of 2.5%,degree of acetylation(DA)of 4%,molecular weight(MW)of 2.973×10^(5)(g/mol).The second route produces chitosan 2 with higher yield of 41%,degree of acetylation(DA)of 17.23%,molecular weight(MW)of 2.939×10^(5)(g/mol).Both chitosans were characterized by XRD,FTIR,^(1)H-NMR spectroscopy nuclear magnetic resonance of proton.The molecular weight(MW)was determined by size exclusion chromatography(SEC).Thermal analysis shows that both chitosans have moisture content lower than 10%.However chitosan 2 has the less ash%which is the quality grade for chitosan medical applications.Accordingly,fungal chitosan 2 could have potential medical and agricultural applications.