Development of gelatinized-core liposomes for the oral delivery of EGCG with improved stability, release property, and cellular antioxidant activity

Epigallocatechin gallate (EGCG) exhibits antioxidant, anti-cancer, and anti-inflammatory properties; however, low cellular permeability and stability limit its bioavailability. Liposomes have the potential for enhancing bioactive compounds' bioavailability. Yet, low entrapment efficiency (EE) and burst release of hydrophilic substances make them impractical for food industry use. Here, we incorporated gelatin into liposomes to overcome these limitations. EGCG-loaded conventional liposomes (EGCG/CLs) and gelatinized-core liposomes (EGCG/GLs) had small particle sizes and high absolute zeta potentials. Encapsulation in EGCG/GLs significantly improved the EE of EGCG compared to that in EGCG/CLs (p < 0.05). EGCG/GLs retained EGCG in the hydrophilic region, whereas EGCG/CLs exhibited significantly higher release of EGCG during storage (p < 0.05). Additionally, in comparison to EGCG/CLs, gelatin incorporation significantly enhanced the sustained release, cellular permeability, and cellular antioxidant activity of EGCG (p < 0.05). This study emphasizes the capability of gelatinized-core liposomes as a potent delivery system for enhancing the stability and bioavailability of EGCG/ CLs, broadening the prospects for utilizing them in the food industry.