Β-Lactoglobulin interacting with phlorizin alters its GI digestive peptide profile and synergistically enhances...

Phlorizin (PZ), a naturally occurring flavonoid glycoside in Malus exhibits dual therapeutic potential as an antioxidant and antidiabetic agent, however its clinical translation is constrained by poor aqueous solubility (<0.1 mg/mL) and suboptimal bioavailability. To address these limitations, this study examined supramolecular complexation with β-lactoglobulin (β-LG), a whey protein carrier capable of hydrophobic nutrient transport and known for its immunomodulatory properties. Furthermore, the molecular binding mechanism, gastrointestinal stability, and synergistic effects of the PZ-β-LG complex on intestinal mucosal secretion were systematically characterized by integrating computational simulations, spectroscopic validation, and in vitro functional assays. Molecular dynamics simulations revealed that the PZ preferential bound within the calyx domain of β-LG (ΔG = -8.3 kcal/mol) through hydrophobic interactions and hydrogen bonding, as evidenced by emerging UV-Visible absorption peaks between 300 and 350 nm and intrinsic fluorescence spectroscopy. Simulated gastrointestinal digestion coupled with Liquid Chromatography-Tandem Mass Spectrometry(LC-MS/MS) peptidomics demonstrated a significant reduction in β-LG antigenicity reduction(52.1% vs. free β-LG; P < 0.01), which might be attributed to the enhanced gastrointestinal hydrolysis efficiency and the masking of immunoreactive epitopes Notably, 2 digestion-resistant peptides (VAGTWY-42 and LDAQSAPLR-89) persisted across all groups, suggesting potential allergenicity hotspots that may require further investigation. Cellular assessments using intestinal epithelium LS174T cells revealed that β-LG complexation reduced PZ associated cytotoxicity by 62% (P < 0.05) while synergistically upregulating the expression of mucin-2 (MUC2) at both transcriptional (2.5-fold increase) and secretory levels (2.1-fold elevation vs. control). Overall, these findings indicate that hydrophobic-driven complexation PZ with β-LG not only enhances the bioavailability of polyphenol but also decreases the antigenicity of protein carrier in intestine cells.