Investigation of the impact of black chokeberry polyphenols in different matrices on the human gut microbiota using the in vitro model of the large intestine (TIM-2)

BACKGROUND: Despite the great range of health-beneficial activities associated with dietary polyphenols, their influence on gut ecology remains poorly understood. Only a few studies have examined the impact of black chokeberry polyphenols present in different matrices on human gut microbiota, and in fact none have examined encapsulated black chokeberry polyphenols. OBJECTIVE: The objective of this study was to evaluate the effect of black chokeberry polyphenols in pulp, extract and encapsulate (in a maltodextrin:gum Arabic polymer system) on human gut microbiota and fecal short-chain and branched-chain fatty acids (SCFA and BCFA, respectively). METHODS: The effect of black chokeberry polyphenols on gut microbiota was tested in a validated, dynamic in vitro model of the colon (TIM-2) for 24 h by applying five different interventions (Pulp, Extract, Encapsulate, Encapsulate control, SIEM) to the standardized microbiota from five healthy donors. RESULTS: We observed that the fermentation of black chokeberry polyphenols in the in vitro colon model resulted in shifts in the standardized microbiota and differentiation in the extent of the production of SCFA and BCFAs. Synergy between maltodextrin+gum Arabic+polyphenols resulted in an increase in the relative abundances of some health-promoting taxa and decrease in the disease related taxa Alistipes. Encapsulation increased the SCFA production and decreased the BCFA production in the lumen. CONCLUSIONS: Although encapsulation of polyphenols may provide a robust way for their protection during their transit along the upper gastrointestinal tract, their effect on the gut microbiota should be further investigated both by using different coating materials and with in vivo studies.