Advances in β-mannanase research: from structural insights to biotechnological applications

β-Mannanases are important hemicellulases that cleave β-1,4-mannosidic bonds in mannan-rich polysaccharides, a common building block of plant cell walls. β-Mannanases are broadly distributed across bacteria, fungi, and plants and exhibit diverse structural frameworks and catalytic mechanisms that enable their functional diversity. Molecular biology, recombinant expression, and bioprocess optimization have enabled the efficient production of these enzymes, whereas structural and mechanistic studies provide insights for protein engineering. Due to their capacity for mannan modification and degradation, β-mannanases have been utilized in animal feed, food processing, paper and textile industries, oil recovery, and biorefinery. This review examines existing information on the structure, origin, production strategy, and industrial applications of β-mannanases, as well as their potential for future use in sustainable biotechnological processes.