Stability, Irritation Property and Anti-aging Clinical Evaluation of Hydroethanolic Dimocarpus longan Leaf Extract-Loaded Niosomes

This study aimed to develop hydroethanolic Dimocarpus longan leaf extract (HDLE)-loaded niosomes for enhancing polyphenols’ stability and efficiency for cosmeceutical applications. Moreover, its irritation property was clinically evaluated. HDLE was loaded into niosomes of cholesterol, sorbitan laurate, and polysorbate 20 at a 1:1:1.5 molar ratio. The suitable extract-loaded capacity was 0.5% (w/w), which provided the percentage of entrapment efficiencies of gallic acid, ethyl gallate and ellagic acid at 37.77 ± 0.93, 49.76 ± 0.20, and 62.85 ± 1.55, respectively. The HDLE-loaded niosomes showed a unilamellar structure under a transmission electron microscope. The particle size range was 255.45-356.15 nm with a low polydispersity index at initial and after storage for three months. The remaining percentage of gallic acid, ethyl gallate and ellagic acid in HDLE-loaded niosomes at all storage temperatures after three months was significantly higher than in the solution. HDLE-loaded niosomes presented no irritation effect on the chorioallantoic membranes (CAMs). The serum containing HDLE-loaded niosomes showed no irritation by the 4-hr human patch test. After applying twice daily for 60 days of water-based serum containing the HDLE-loaded niosomes compared with a placebo and untreated skin on different areas of forearms, the result demonstrated that HDLE-loaded niosomes serum was significantly effective in skin moisturization, elasticity induction and wrinkle reduction. In conclusion, due to their efficacy and safety, HDLE-loaded niosomes can be used for cosmetic applications.