Depolymerization and Nanoliposomal Encapsulation of Grape Seed Condensed Tannins: Physicochemical Characterization, Stability, In Vitro Release and Bioaccessibility.

ABSTRACT: Condensed tannins from grape seed residues show high antioxidant activity but low oral bioavailability because of their high degree of polymerization and covalent interactions with proteins. This study aimed to improve their bioaccessibility through depolymerization and encapsulation. Depolymerization was carried out using microwave-assisted SN1 reactions with gallic acid as a nucleophile under food-grade conditions, mainly producing epicatechin monomers with 99.8% polymer degradation efficiency. Importantly, the inhibition of ABTS●+ and DPPH● radicals remained unaffected (p > 0.05), indicating that depolymerization preserved the antioxidants' redox function, maintaining about 90% of their inhibition activity. The products were encapsulated in phosphatidylcholine liposomes, which ha

SUBMITTER: Morales CF 

PROVIDER: S-EPMC12466359 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature