Improving Growth Dynamics of Faecalibacterium prausnitzii by Exposure to Prebiotics

Faecalibacterium prausnitzii, a major butyrate-producing gut commensal with anti-inflammatory activity, is extremely oxygen-sensitive, limiting its use as a probiotic. Dietary prebiotics may enhance its growth and resilience, thereby influencing host immune responses. This study examined how distinct classes of prebiotics including oligosaccharides (fructooligosaccharides, arabinoxylan), nondigestible polysaccharides (inulin, pectin, resistant starch, golden kiwi fiber), and the vitamin riboflavin affect the growth kinetics, bile tolerance, and immunomodulatory properties of F. prausnitzii. Doubling times were quantified in MRS medium supplemented with 0–2% prebiotics, bile tolerance was assessed under 0–0.5% bile salts, and immunomodulatory response was evaluated by measuring TNF-α expression in monocytic THP-1 cells exposed to bacterial supernatants. All prebiotics significantly reduced doubling times compared with controls, with FOSs, inulin, pectin, resistant starch, and riboflavin showing clear dose-dependent stimulation. Prebiotics also mitigated bile-induced growth delays, though with substrate-specific patterns; pectin and FOSs conferred the strongest protection. Culture supernatants significantly altered TNF-α expression, with pectin inducing the greatest response, followed by arabinoxylan, FOSs, and golden kiwi fiber. Overall, prebiotics enhanced F. prausnitzii growth, increased stress resilience, and differentially modulated immune-related metabolites. Pectin emerged as a particularly effective substrate for promoting microbial function and host-relevant immunomodulation.