a review study of liposomal formulations of green tea extracts

Aim and background: green tea extracts are rich in low molecular weight of polyphenols that include mainly of catechins such as egc, ecg, egcg and ec. egcg is the most abundant catechins found in green tea extracts which has significant usage. the catechins (especially egcg) have demonstrated a wide range of beneficial health effects like antioxidant, anti-inflammatory, antibacterial, anticancer. despite these considerable benefits, the application of catechins is limited due to their low oral bioavailability, instability and sensitivity toward temperature, light and ph. nano drug delivery systems like liposomes which are made up of natural or synthetic lipids with a polar head in a variety of sizes are suitable platforms to delivery of drugs, proteins, enzymes and natural products. these lipid-based spherical shaped nano drug delivery systems are used to encapsulate both hydrophilic and hydrophobic agents, protect substances against degradation, prolongs sustainable drug release and also liposomes enhance solubility and bioavailability of the encapsulated agents. several studies shown that the liposomal formulations of egcg with different types of lipids, preparation methods and vesicle sizes have a high ratio of encapsulation efficiency, more stability and solubilization, and higher antioxidant activity. in addition, the combination of green tea extracts with other compounds improves their functionality to be used more widely in food, cosmetics and pharmaceutical industry.conclusion: thus, this study provides the basis for the development of promising liposomal formulations of green tea extracts that might enhance their effectiveness and overcome the problem of stability and bioavailability of green tea extracts.