REVIEW: Chitin/Chitosan and Its Derivatives: Fundamental Problems and Practical Approaches

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V. P. Varlamov^1,a*, A. V. Il’ina¹, B. Ts. Shagdarova¹, A. P. Lunkov¹, and I. S. Mysyakina²

¹Laboratory of Biopolymer Engineering, Institute of Bioengineering, Federal Research Center “Fundamentals of Biotechnology”, Russian Academy of Sciences, 117312 Moscow, Russia

²Winogradsky Institute of Microbiology, Federal Research Center “Fundamentals of Biotechnology”, Russian Academy of Sciences, 117312 Moscow, Russia

^* To whom correspondence should be addressed.

Received June 19, 2019; Revised July 15, 2019; Accepted July 19, 2019

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In this review, we present the data on the natural occurrence of chitin and its partially or fully deacetylated derivative chitosan, as well as their properties, methods of modification, and potential applications of derivatives with bactericidal, fungicidal, and antioxidant activities. The structure and physicochemical characteristics of the polymers, their functions, and features of chitin microbial synthesis and degradation, including the processes occurring in nature, are described. New data on the hydrolytic microorganisms capable of chitin degradation under extreme conditions are presented. Special attention is focused on the effect of physicochemical characteristics of chitosan, including molecular weight, degree of deacetylation, polydispersity index, and number of amino group derivatives (quaternized, succinyl, etc.) on the antimicrobial and antioxidant properties of modified polymers that can be of particular interest for biotechnology, medicine, and agriculture. Analysis of the available literature data confirms the importance of fundamental research to broaden our knowledge on the occurrence of chitin and chitosan in nature, their role in global biosphere cycles, and prospects of applied research aimed at using chitin, chitosan, and their derivatives in various aspects of human activity.

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KEY WORDS: chitin, chitosan, chitosan derivatives, chitosan depolymerization, bactericidal, fungicidal, and antioxidative activity

DOI: 10.1134/S0006297920140084

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