Ionic liquid pretreatment modulates the composition of individual corn bran feruloylated oligosaccharide and the mucin O-glycanases regulation activity

[Bmim]Cl-assisted xylanase hydrolysis enriches FAX 3 to 258.39 mg/g FOs. • FOs increased sialidase activity but suppressed that of α-N-acetylglucosaminidase and β-galactosidase vs control ( p < 0.05). • FOs with higher FAX 3 /FAX 2 ratio showed significantly stronger inhibition of exo -α-L-fucosidase ( p < 0.05). Feruloylated oligosaccharides (FOs) are bioactive conjugates that exhibit promising synergistic effects on gut microbiota modulation and intestinal barrier protection, yet their efficacy is highly structure-dependent. This study developed a synergistic strategy combining ionic liquid (IL, 1-butyl-3-methylimidazolium chloride) pretreatment with xylanase hydrolysis to selectively produce feruloylated arabinoxylobiose (FAX 2 ) and feruloylated arabinoxylotriose (FAX 3 ) from corn bran. The IL-pretreated FOs (FOsA) achieved a FAX 3 /FAX 2 ratio of 4.86, which was 2.16-fold higher than that of the non-pretreated group (FOsB). Although in vitro assays confirmed that FOs were not directly utilized as a carbon source by Akkermansia muciniphila ( A. muciniphila ), both FOsA and FOsB significantly modulated its mucin-degrading enzyme activities ( p  < 0.05). Specifically, both fractions increased sialidase activity while reducing α- N -acetylglucosaminidase and β-galactosidase activities. Notably, FOsA, with a higher FAX 3 /FAX 2 ratio, exhibited significantly stronger inhibition of exo -α-L-fucosidase activity than FOsB ( p < 0.05 ). These findings demonstrate that FOs act as effective modulators of A. muciniphila enzymatic functions rather than metabolic substrates, and that their fine structural composition critically influences their regulatory potency on mucin-degrading enzymes, with potential implications for maintaining intestinal mucus barrier integrity. Download: Download high-res image (320KB) Download: Download full-size image