Tea polyphenols-loaded nanocarriers: preparation technology and biological function

Tea polyphenols (TP) have various biological functions including anti-oxidant, anti-bacterial, anti-apoptotic, anti-inflammatory and bioengineered repair properties. However, TP exhibit poor stability and bioavailability in the gastrointestinal tract. Nanoencapsulation techniques can be used to protect TP and to uphold their original characteristics during processing, storage and digestion, improve their physiochemical properties and enhance their health promoting effects. Nano-embedded TP show higher antioxidant, antibacterial and anticancer properties than TP, allowing TP to play a better role in bioengineering restoration after embedding. In this review, recent advances in nanoencapsulation of TP with biopolymeric nanocarriers (polysaccharides and proteins), lipid-based nanocarriers and innovative developments in preparation strategies were mainly discussed. Additionally, the strengthening biological functions of stability and bioavailability, antioxidant, antibacterial, anticancer activities and bioengineering repair properties activities after the nano-embedding of TP have been considered. Finally, further studies could be conducted for exploring the application of nanoencapsulated systems in food for industrial applications.