Abstract
Polysaccharides are biopolymers made up of a large number of monosaccharides joined together by glycosidic bonds. Polysaccharides are widely distributed in nature: Some, such as peptidoglycan and cellulose, are the components that make up the cell walls of bacteria and plants, and some, such as starch and glycogen, are used as carbohydrate storage in plants and animals. Fungi exist in a variety of natural environments and can exploit a wide range of carbon sources. They play a crucial role in the global carbon cycle because of their ability to break down plant biomass, which is composed primarily of cell wall polysaccharides, including cellulose, hemicellulose, and pectin. Fungi produce a variety of enzymes that in combination degrade cell wall polysaccharides into different monosaccharides. Starch, the main component of grain, is also a polysaccharide that can be broken down into monosaccharides by fungi. These monosaccharides can be used for energy or as precursors for the biosynthesis of biomolecules through a series of enzymatic reactions. Industrial fermentation by microbes has been widely used to produce traditional foods, beverages, and biofuels from starch and to a lesser extent plant biomass. This review focuses on the degradation and utilization of plant homopolysaccharides, cellulose and starch; summarizes the activities of the enzymes involved and the regulation of the induction of the enzymes in well-studied filamentous fungi.
Highlights
Polysaccharides are relatively complex carbohydrates that are widely distributed in nature.They are biopolymers made up of a variety of monosaccharides joined together by glycosidic bonds.Plant polysaccharides are the most abundant carbon source and can be divided into plant cell wall polysaccharides and storage polysaccharides [1,2,3].All plant cells are surrounded by complex cell walls, and secondary cell walls form the architecture of plant biomass
Cellulose fibrils are synthesized at the plasma membrane, while hemicelluloses and other matrix polysaccharides are produced in the Golgi apparatus [4]
AceII is a transcriptional activator of all major cellulolytic enzyme genes, including cbh1, cbh2, egl1, egl2, and xylanolytic gene xyn2, whereas AceI is an inhibitor of cellulase and xylanase expression [86]
Summary
Polysaccharides are relatively complex carbohydrates that are widely distributed in nature. The cellulosic polymer has been described by a two-phase model, consisting of crystalline and amorphous phases often interrupted by a series of semicrystalline structures, which makes it difficult to be utilized by active carbohydrate enzymes [9] Compared with cellulose, another major component of plant cell wall polysaccharides, hemicelluloses, are more diverse and complex heterosaccharides, which are derived from a heterogeneous group of sugars including D-xylose, D-galactose, and D-mannose. The gradually increasing global energy crisis requires us to further develop and explore new bioenergy and other renewable energy sources, such as the use of lignocellulose biomass resources by microbial anaerobic fermentation [27] Another application of cellulose is nanocellulose materials, which are nontoxic, biodegradable, and biocompatible and have no adverse effect on the environment and human health. We aimed to better understand the degradation of plant polysaccharides and the regulatory mechanisms of related enzymes that can help us to acquire better strains that are more suitable for industrial fermentation utilization
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
