Green fabrication of chitosan from marine crustaceans and mushroom waste: Toward sustainable resource utilization

Abstract The exoskeletons of crabs, shrimp, and fish are major waste. These wastes contain chitin, an abundant natural polymer found next to cellulose. Thus, disposal of this waste becomes a huge problem for the environment; besides this, reutilization boosts the circular economy. Chitin is partially deacetylated to yield the economically useful product of chitosan and is a heteropolymer. The current study isolated chitosan from mushrooms and various marine crustaceans, i.e., crabs, shrimp, and fish. Chitosan was extracted from marine crustaceans by demineralization, deproteination, and deacetylation. Later, extracted chitosan was characterized by physicochemical characteristics like deacetylation degree, ash content, protein, color, fat-binding capacity (FBC), water-binding capacity (WBC), pH, and moisture content. The result showed that chitosan yield ranges from 13.0% to 17.0%, the degree of deacetylation range from 82.0% to 85.0%, ash content range from 0.8% to 3.0%, and protein content is below 1.0%. The FBC and WBC range between 320% and 444% and 535% and 602%, respectively. The pH and moisture content range from 7.4 to 8.0 and from 2.0% to 4.0%, respectively. Overall, results specified that crustacean waste was an exceptional chitosan source with availability and production consistency.