Enzymatic Cocktail Formulation for Xylan Hydrolysis into Xylose and Xylooligosaccharides

Abstract

In the context of a biorefinery, lignocellulosic materials represent an important source of raw material for the bioconversion of cellulose, hemicellulose, and lignin into value-added products, such as xylose for fermentation, oligosaccharides, and bioplastics for packaging. Among the most abundant lignocellulosic materials in Brazil, sugarcane bagasse biomass stands out, as it is rich in cellulose and hemicellulose. In this context, through an experimental design, this study developed a robust enzyme cocktail containing xylanases and accessory enzymes to complete the hydrolysis of xylan from sugarcane bagasse, obtaining a low xylose yield and concentration (9% and 1.8 g/L, respectively, observed in experiment number 16 from the complete hydrolysis of a xylan assay), a fermentable sugar that is important in the production of second-generation ethanol, and a high xylooligosaccharides (XOS) yield and concentration (93.1% and 19.6 g/L, respectively, obtained from a xylooligosaccharides production assay); in general, xylan has prebiotic activities that favor an improvement in intestinal functions, with immunological and antimicrobial actions and other benefits to human health. In addition to completely hydrolyzing the sugarcane bagasse xylan, this enzymatic cocktail has great potential to be applied in other sources of lignocellulosic biomass for the conversion of xylan into xylose and XOS due to its enzymes content, involving both main chain and pendant groups hydrolysis of hemicelluloses.

A 28-Day Repeated Oral Administration Study of Mechanically Fibrillated Cellulose Nanofibers According to OECD TG407

“…It is possible that the effect of fib-CNF on intestinal bacteria led to weight loss. Numerous studies and review articles discuss the degradation of cellulose and other dietary fibers by intestinal bacteria [24][25][26][27][28][29][30][31][32][33][34]. Although cellulose is a central component of plant fiber and is abundant in diets with plant-derived foods, humans, like other mammals, rely on gut microbiota to break down cellulose.…”

Xylooligosaccharides from Biomass Lignocellulose: Properties, Sources and Production Methods

“…The described structure of xylan determines the complexity of its complete enzymatic hydrolysis; therefore, for this purpose, the complex action of various enzymes is often used. α-L-arabinofuranosidases, α-D-glucuronidases, acetylxylanesterases, ferulic acid esterases and p-coumaric acid esterases act on various substituents of the branched xylan molecule, thereby increasing the availability of the xylose backbone for the action of xylanases [24,25,26]. It was shown that the yield of XOS during the combined destruction of lignocellulosic biomass by xylanase and arabinofuranosidase was 95.03% versus 30% when using single enzymes [9].…”