Valorizing date fruit byproducts into gut-modulating substrates: metabolomic profiling and in vitro insights

This study investigates the prebiotic potential of date seed (DS) and date pomace (DP), two major agro-industrial byproducts, using a combined metabolomic and functional approach. Untargeted LC–MS profiling revealed distinct metabolite patterns in the two byproducts: DP showed a greater proportion of soluble sugars and carbohydrate-derived organic acids, whereas DS showed a broader distribution of antioxidant-, aromatic-, and lipid-associated metabolites. In vitro screening with four probiotic strains showed that Bifidobacterium bifidum exhibited the highest viability in 2% DP and produced the highest levels of fermentation-derived short-chain fatty acids (SCFAs). Lactobacillus acidophilus demonstrated optimal growth in 3% DS. SCFAs from DP–B. bifidum cultures displayed antimicrobial activity against common food-borne Gram-negative pathogens (Salmonella MIC₈₀ = 280 µg/mL) and selectively suppressed cyclooxygenase-2 (COX-2), suggesting anti-inflammatory properties. These findings position DS and DP as sustainable gut-modulating substrates that selectively support probiotic growth and SCFA production, suggesting that date-processing waste can be converted into functional ingredients with gut-modulating, antimicrobial, and anti-inflammatory potential.