Efficient Production of Mano/Xylo-Oligosaccharides with Excellent Probiotic Activity through Coupling Catalysis

This study develops a catalytic system using pyruvic acid (PYA) and Fe2+ to efficiently coproduce xylo-oligosaccharides (XOS) and (manno-oligosaccharides) MOS from food material (Gleditsia sinensis Lam. fruit.) and its waste peel, respectively. The system achieved maximum yields of 67.12% XOS and 57.32% MOS without toxic byproducts such as furfural and 5-hydroxymethylfurfural (5-HMF) below 130 °C. The process employs a two-stage mechanism, where PYA cleaves galactose side chains and xylan backbones, while Fe2+ stabilizes β-1,4-glycosidic bonds, resulting in polymerization degree ratios of X2–3/X4–5 at 0.975 and M2–3/M4–5 at 0.96. The composite oligosaccharides, PFMX, showed significant prebiotic effects, enhancing Bifidobacterium adolescentis growth to 3.4 × 108 CFU/mL─144% higher than commercial fructooligosaccharides (FOS). The concentration of short-chain fatty acids (SCFAs) was 15.09 g/L, with specific products propionic acid (1.44 g/L) and butyric acid (0.15 g/L). PFMX effectively regulates substrate utilization and SCFA metabolism, offering a promising strategy for developing functional foods that target gut inflammation.