Bioaccessibility of phloretin and its derivatives using a dynamic in vitro digester. Effects on glucose uptake, bacterial growth and anti-inflammatory activity

This work investigated the bioaccessibility of distinct derivatives of phloretin using an in vitro dynamic digestion model that simulates human gastrointestinal conditions. Four compounds were compared: aglycone, α-glucoside, α-diglucoside and lauroyl α-glucoside. The presence of glucosyl groups attached to phloretin enhances the bioaccessibility of the flavonoid. Most of the α-glucoside reaches the intestine as the aglycone, due to the action of intestinal glycosidic enzymes. In contrast, both phloretin and lauroyl α-glucoside precipitate in the stomach phase, which limits their availability. Phloretin α-glucoside showed higher bioavailability (26.8 %) in Caco-2 cells compared to the aglycone (2.7 %), likely due to active transport. In contrast, the α-diglucoside had lower bioavailability (4.4 %), and lauroyl α-glucoside was not absorbed. In addition, phloretin and its derivatives demonstrated inhibitory effects on intestinal glucose absorption using Caco-2 cells. Lauroyl α-glucoside selectively inhibited pathogenic bacterial growth without affecting probiotics and also exhibited anti-inflammatory effects.