Chitosan: An in-Depth Analysis of Its Extraction, Applications, Constraints, and Future Prospects

The primary focus of this review is an eco-friendly biopolymer chitosan which is mainly produced by the conversion of environmental wastes into useful applications. Chitosan has drawn much interest due to its unusual characteristics, including anti-microbial, biodegradability, and non-toxicity. This study explores numerous approaches available for the production and extraction of chitosan from various sources, including crustaceans, fungi, and insects. The available techniques are classified into chemical and biological methods and further divided into enzymatic and fermentation methods. This review also covers the steps in the upstream and downstream processes that are involved in the production of chitosan. Additionally, a few techniques available for the characterization of chitosan are covered, including Fourier transform infrared spectroscopy, potentiometric titration, differential scanning calorimetry, thermogravimetric analysis, X-ray powder diffraction, and emission scanning electron microscopy. Comparisons are also made between the characteristics of chitosan derived from sources like insects and fungal strains. Characteristics of chitosan obtained from sources such as fungal strains and insects are compared with those of commercial chitosan. This study also focuses on the most recent applications of chitosan in the medical sector, wastewater treatment plant, agricultural sector, food packaging industry, and cosmetic industry. A few patents related to chitosan in the health sector are also discussed. Finally, it concludes that further research on chitosan and its derivatives is necessary to fully understand the advantages of this polymer. It also emphasizes the difficulties involved in extracting chitosan from crustaceans, insects, and fungi. To fully explore the advantages of this polymer, it is concluded that further research into chitosan and its derivatives is necessary.