Synthesis of potential prebiotic oligosaccharides with diverse glycosidic linkages from corn stover via simultaneous hydrolysis and glycosylation

This study presents the synthesis of potential prebiotic oligosaccharides directly from corn stover using concentrated sulfuric acid as both solvent and catalyst under mild conditions. The process involves dissolving corn stover at 20 °C for 1 h, followed by simultaneous hydrolysis of cellulose and hemicellulose and glycosylation of the resulting mono- and oligo-saccharides at 50 °C for 10 min in 80 wt% H₂SO₄. A yield of 48.8 % of corn stover-derived oligosaccharides (CS-OS) was achieved, nearing the theoretical yield. Structural analysis revealed that CS-OS were primarily gluco-oligosaccharides (average degree of polymerization (DP) 4.3) and xylo-oligosaccharides (average DP 3.6) with diverse α/β-(1→6/4/3/2/1) glycosidic bonds. Preliminary in vitro evaluation demonstrated that CS-OS effectively supported the growth of three probiotic strains (Lactobacillus and Pediococcus), outperforming commercial prebiotic isomalto-oligosaccharides and matching commercial prebiotic xylo-oligosaccharides. This study offers a valuable method to convert agricultural waste lignocellulosic biomass into valuable prebiotic oligosaccharides.