Combination of Lycium barbarum polysaccharide and chlorogenic acid: Characterization of solution property, interaction, and regulatory function on typical gut Bacteroides and pathogens

Lycium barbarum polysaccharide (LBP) is a prebiotic that promotes the proliferation of beneficial bacteria, but lacks of regulatory function on harmful bacteria. In this study, chlorogenic acid (CGA) was used to achieve the functional enhancement of two LBPs (LBP-A and LBP-M). The combination of CGA resulted in changes in the solution properties of LBPs, manifested as increased pseudoplasticity, viscosity, turbidity, and decreased water mobility, absolute potential value, pH value. CGA was non-covalently bound to LBPs through hydrophobic interaction and hydrogen bond. LBP-A had strong affinity with CGA, mainly through hydrophobic interaction, while LBP-M had weak affinity with CGA, mainly through hydrogen bond. Both LBP-CGA complexes exhibited Bacteroides proliferative activity and gut pathogens inhibitory activity, among which LBP-A-CGA complex showed strong inhibitory effects on Escherichia coli and Bacillus cereus , and LBP-M-CGA complex showed strong inhibitory effect on Staphylococcus aureus . This study provided guidance for the development of LBP-CGA as novel prebiotic.