Hemicellulose and lignin are two major components of plant cell walls, each with distinct chemical structures and properties that require specialized microorganisms for their degradation. Hemicellulose is a heterogeneous polysaccharide composed of various sugar monomers, such as xylose, mannose, glucose, and arabinose, arranged in a branched structure. Its amorphous nature and solubility in water make it relatively easier to hydrolyze compared to cellulose. Lignin, on the other hand, is a complex aromatic polymer composed of phenylpropanoid units linked by diverse bonds, such as β-O-4, α-O-4, and C–C linkages. Its highly recalcitrant, hydrophobic, and irregular three-dimensional structure makes it resistant to chemical and biological attack, posing a major challenge in biomass degradation. Environmental biotechnology focuses on employing specialized microorganisms and enzymatic processes to break down these components, thereby facilitating biomass utilization, waste management, and soil carbon cycling. Microorganisms capable of degrading hemicellulose include various bacteria and fungi. Fungal species, particularly from the genera *Aspergillus*, *Trichoderma*, and *Penicillium*, are well-known hemicellulolytic organisms. These fungi secrete a range of extracellular enzymes, collectively termed hemicellulases, which include xylanases, mannanases, β-xylosidases, α-arabinofuranosidases, and acetyl esterases. These enzymes act synergistically to cleave the backbone of hemicellulose and remove side-chain decorations, producing soluble sugars that microorganisms can metabolize for energy and growth. Bacterial species, including members of *Bacillus*, *Clostridium*, and *Paenibacillus*, also exhibit hemicellulose-degrading abilities. Bacteria often demonstrate faster growth rates and can operate under a wider range of environmental conditions compared to fungi, making them suitable for industrial applications such as bioethanol production from lignocellulosic biomass. Hemicellulose degradation typically begins with the adsorption of enzymes to the polysaccharide surface, followed by endo-acting cleavage of internal bonds and exo-acting removal of terminal sugars, ultimately releasing monosaccharides and oligosaccharides. Lignin-degrading microorganisms are predominantly fungi, particularly white-rot and brown-rot basidiomycetes. White-rot fungi, such as *Phanerochaete