Chemical and physical Chitosan modification for designing enzymatic industrial biocatalysts: How to choose the best strategy?

Chitosan is one of the most abundant natural polymer worldwide, and due to its inherent characteristics, its use in industrial processes has been extensively explored. Because it is biodegradable, biocompatible, non-toxic, hy-drophilic, cheap, and has good physical-chemical stability, it is seen as an excellent alternative for the replace-ment of synthetic materials in the search for more sustainable production methodologies. Thus being, a possible biotechnological application of Chitosan is as a direct support for enzyme immobilization. However, its applicability is quite specific, and to overcome this issue, alternative pretreatments are required, such as chem-ical and physical modifications to its structure, enabling its use in a wider array of applications. This review aims to present the topic in detail, by exploring and discussing methods of employment of Chitosan in enzymatic im-mobilization processes with various enzymes, presenting its advantages and disadvantages, as well as listing pos-sible chemical modifications and combinations with other compounds for formulating an ideal support for this purpose. First, we will present Chitosan emphasizing its characteristics that allow its use as enzyme support. Fur-thermore, we will discuss possible physicochemical modifications that can be made to Chitosan, mentioning the improvements obtained in each process. These discussions will enable a comprehensive comparison between, and an informed choice of, the best technologies concerning enzyme immobilization and the application condi-tions of the biocatalyst. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

Chitosan is a natural polymer widely used in industrial processes due to its biodegradability, biocompatibility, and other advantageous characteristics. However, to expand its applicability, chemical and physical modifications are required to adapt to different applications.