glucanase

Glucanase is a generic term for enzymes that catalyze the hydrolysis of glucans, polysaccharides composed of glucose units linked by various glycosidic bonds. They belong to the glycoside hydrolase family and occur in plants, fungi, bacteria, and some other organisms. Glucanases differ in substrate preference (alpha- versus beta-glucans) and in their mode of action (endo-acting, cutting within the polymer, or exo-acting, removing units from the ends).

Common subtypes include beta-1,3-glucanases and beta-1,4-glucanases, which degrade beta-linked glucans such as those found in fungal cell walls and in plant cell walls, respectively. Some glucanases also act on alpha-glucans, though these activities are less common and may overlap with activities of other enzyme families. Endoglucanases tend to generate shorter fragments internally, while exoglucanases release defined oligosaccharides from chain ends, including monosaccharides in some cases.

Biological roles of glucanases vary: in plants, glucanases contribute to defense against fungal pathogens by weakening their cell walls; in microorganisms, they assist in nutrient acquisition by breaking down environmental glucans; in ecosystems, they participate in carbon cycling and saprophytic processes.

Industrial and research applications are diverse. In baking and brewing, glucanases reduce viscosity and improve filtration and process efficiency by breaking down glucans in doughs and worts. In animal nutrition, they enhance feed digestibility. They are also used in pulp and paper processing, textile treatment, and crop protection research as biocontrol agents.

Production and regulation: glucanases are produced by microbes, plants, and some animals, and are available as purified enzymes or within commercial processing aids. Regulatory status and labeling vary by jurisdiction and application.

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