Xylitol production from lignocellulosic biowastes

Abstract

Xylitol is an increasingly popular sugar substitute in food, pharmaceutical, and personal care products. It is a pentitol-type polyol, exhibiting broad OH stretching bands at 3200–3600 cm⁻¹ indicating multiple hydroxyl groups and distinct structural characteristics. Traditionally produced through chemical processes, xylitol production has shifted towards more sustainable biotechnological methods using lignocellulosic biowaste like sugarcane bagasse, corn cobs, and wheat and rice straw. Xylose Reductase (XR) and Xylitol Dehydrogenase (XDH), are instrumental in biotechnological production, and metabolic engineering advances have improved xylitol yield by optimizing these pathways and enabling co-utilization of sugars in mixed hydrolysates. Techno-Economic Analysis (TEA) and Life Cycle Assessment (LCA) reveal that biotechnological methods, while eco-friendly and adaptable, are currently more feasible at smaller scales compared to the capital-intensive chemical methods preferred for large-scale biorefineries. This review emphasizes the potential of lignocellulosic biowaste as feedstock for xylitol production, underscoring the importance of metabolic engineering, process optimization, and sustainability.