Woodfordia fruticosa extract supplementation stimulates the growth of Lacticaseibacillus casei and Lacticaseibacillus rhamnosus with adapted intracellular and extracellular metabolite pool.

Abstract

To investigate the effect of Woodfordia fruticosa extract (WfE) on two probiotic bacteria: Lacticaseibacillus casei and Lacticaseibacillus rhamnosus. WfE supplementation at 0·5 and 1 mg ml-1 stimulated probiotic growth (P < 0·05), enhanced adhesion to CaCO2 cells (P < 0·05) while inhibiting foodborne pathogens Escherichia coli and Staphylococcus aureus (P < 0·05). 1 H-NMR based metabolomic studies indicated higher glucose : lactate and glucose : acetate in the extracellular matrix with significant variation (P < 0·05) in intracellular concentrations of lactate, acetate, glutamate, dimethylamine, phenylalanine, branched-chain amino acids and total cellular lipid composition. Fatty acid methyl ester analysis showed a chemical shift from saturated to unsaturated lipids with WfE supplementation. PCA plots indicated clear discrimination between test groups, highlighting variation in metabolite pool in response to WfE supplementation. Phytonutrient-rich WfE exhibited prebiotic-like attributes, and probiotic bacteria showed altered metabolite pools as an adaptive mechanism. This is the first report providing insights into the prebiotic-like activity of WfE on gut representative probiotics. The extended metabolomic studies shed light on the positive interaction between phytonutrients and beneficial bacteria that possibly help them to adapt to a phytonutrient-rich WfE environment. WfE with potential prebiotic attributes can be used in the development of novel synbiotic functional products targeting gut microbial modulation to improve health.