Fecal excretion kinetics provides further support for polyphenols targeting microbiota: An example with...

The microbiota plays important roles for polyphenols exerting bioactivity, which needs support to calculate the accumulated polyphenols in the gastrointestinal tract. Taking phlorizin as an example, fecal excretion kinetics was suggested to be ingenious for achieving it. No phlorizin was excreted with feces, implying almost 100 % total availability. Combined with its 0-5 % bioavailability, more than 95 % of phlorizin quantitatively accumulated in the gastrointestinal tract. Instead, trace phloretin was excreted, and the acquired kinetic parameters were influenced by physical conditions and dietary patterns. Dosage-total-availability curves indicated different relationships among normal-diet and obese mice, resulting in critical dosages of ∼ 159 and ∼ 196 mg/kg when taking 95 % total availability by phloretin. The dietary matrix affects the intake, digestion, metabolism and absorption of polyphenols, and may alter its total availability, and fecal excretion kinetics can provide further support for polyphenol dietary supplements targeting microbiota.