Improved antioxidant activity, bioaccessibility and bioavailability of EGCG by delivery in β-lactoglobulin particles

Abstract

The green tea catechin (–)-epigallocatechin-3-gallate (EGCG) reportedly has numerous health benefits, e.g., towards prevention of the metabolic syndrome, cancer and neurodegenerative diseases. However, EGCG is sensitive to oxidation, bitter, astringent, and poorly bioavailable. To maximize its therapeutic utility, a novel beta-lactoglobulin (β-Lg)-based delivery system had been developed by our group. These EGCG-β-Lg complexes were found to protect EGCG during shelf-life, and improve its sensory properties. Here, we explored the effect of complexation with β-Lg on EGCG stability, antioxidant activity and in-vivo bioavailability. β-Lg–complexed EGCG showed significantly greater stability and antioxidant activity than free EGCG during simulated digestion. The digested EGCG-β-Lg system exhibited significantly higher EGCG bioaccessibility compered to EGCG alone. Oral administration of EGCG complexed with β-Lg to rats significantly increased the plasma Cmax and area-under-the-curve 2-fold compared with free EGCG. Our results emphasize the great potential of this delivery system in improving bioavailability and efficacy of polyphenols like EGCG.

Keywords

• EGCG
• β-Lactoglobulin
• Antioxidant activity
• Bioaccessibility
• Bioavailability
• Simulated gastrointestinal digestion