Sugarcane polyphenols modulate gut microbiota and odor-associated metabolites during in vitro fecal fermentation of elderly

Gut microbial metabolism generates odor-active compounds that contribute to systemic malodor, particularly in the elderly. However, gut-targeted strategies to mitigate odor remain underexplored. This study evaluated the potential of in vitro gastrointestinal digested sugarcane polyphenols (SP) to suppress odor formation via microbial regulation using an in vitro fecal fermentation model. A combination of 16S rDNA sequencing, solid–phase microextraction coupled with gas chromatography–mass spectrometry (SPME–GC–MS), and ultra–performance liquid chromatography–quadrupole time–of–flight mass spectrometry (UPLC–Q–TOF–MS) was employed to investigate changes in microbial composition, odorant metabolites, and SP biotransformation. SP treatment significantly lowered key odorants, including indole, p-cresol, and dimethyl trisulfide, and selectively suppressed odor-associated taxa such as Enterobacteriaceae , Desulfovibrionaceae , and Veillonellaceae . Conversely, SP enriched beneficial bacteria, particularly Faecalibacterium and Bifidobacterium , suggesting a shift toward a health-associated gut microbial profile. UPLC–Q–TOF–MS identified 2''-O-acetylrutin and 2''-O-acetyl-3'-O-methylrutin as key SP-derived metabolites with putative antibacterial effects, potentially contributing to odor suppression. Exosome inhibition significantly attenuated both deodorization and microbiota remodeling, indicating that exosome-mediated microbial signaling may participate in the metabolic response to SP. These findings provide mechanistic insight into polyphenol-microbiota interactions and support SP as a promising functional dietary component for managing gut-derived malodor and promoting gastrointestinal health in the elderly. Further in vivo studies are needed to confirm these findings.