Current perspective on production and applications of microbial cellulases: a review

Abstract

The potential of cellulolytic enzymes has been widely studied and explored for bioconversion processes and plays a key role in various industrial applications. Cellulase, a key enzyme for cellulose-rich waste feedstock-based biorefinery, has increasing demand in various industries, e.g., paper and pulp, juice clarification, etc. Also, there has been constant progress in developing new strategies to enhance its production, such as the application of waste feedstock as the substrate for the production of individual or enzyme cocktails, process parameters control, and genetic manipulations for enzyme production with enhanced yield, efficiency, and specificity. Further, an insight into immobilization techniques has also been presented for improved reusability of cellulase, a critical factor that controls the cost of the enzyme at an industrial scale. In addition, the review also gives an insight into the status of the significant application of cellulase in the industrial sector, with its techno-economic analysis for future applications. The present review gives a complete overview of current perspectives on the production of microbial cellulases as a promising tool to develop a sustainable and greener concept for industrial applications.

Cellulolytic and Xylanolytic Enzymes from Yeasts: Properties and Industrial Applications

“…EG is reportedly active towards amorphous and crystalline cellulose [33]. Besides these, some other accessory enzymes are also produced, including cellobiose phosphorylase or cellobiase, cellodextrin phosphorylase and cellobiose epimerase [34]. Swollenin and lytic polysaccharide monooxygenases are the other accessory enzymes with broad specificity [35].…”

Genome Analysis of Celeribacter sp. PS-C1 Isolated from Sekinchan Beach in Selangor, Malaysia, Reveals Its β-Glucosidase and Licheninase Activities

“…In terms of COG class for '(G)-carbohydrate transport and metabolism,' a comparable amount of protein-encoding genes were grouped under this category for genomes of strain PS-C1 (219 genes, 5.86%), as well as C. naphthalenivorans EaN35-2 (211 genes, 5.02%). Some of these proteins (β-glucosidase, licheninase, and α-glucosidase) are known to be involved in the degradation of cellulose and starch [35,36,65,66].…”

“…For example, β-glucosidase is the key enzyme that converts cello-oligosaccharides and cellobiose to glucose, which is used as feedstock for bioethanol production [4]. In the food industry, β-glucosidase has been applied as a flavour catalyst to remove aromatic compounds that impart an unpleasant taste to fruit juice, tea, and soy-based products [66]. Moreover, β-glucosidase may be used in the baking process to reduce dough viscosity, thus improving bread texture and quality [67].…”

Plasma Promotes Fungal Cellulase Production by Regulating the Levels of Intracellular NO and Ca2+

“…Currently, biodegradation using cellulases has received great attention due to its effectiveness. However, the production process of cellulases is relatively expensive and contributes to 50% of the total hydrolysis cost [ 4 ]. Therefore, finding a feasible method to increase the yield of cellulases and reduce its production costs is necessary.…”

“…Finally, cellobiose is decomposed into glucose by β-glucosidase, while β-glucosidase can also degrade some cello-oligosaccharides into cellobiose and glucose [ 6 ]. Recently, cellulase became the third most important industrial enzyme in the global enzyme market, according to statistics from 2020, and this is expected to be the case at least until 2027 [ 4 ].…”