Quality Control of Litchi chinensis Leaf: a Potential Raw Material for Cosmetic Industry

Litchi chinensis Sonn., Sapindaceae, is native to southern China and the leaves are mostly employed by Chinese as a traditional medicine, or topically to treat skin disease. This study aimed to investigate the influence of the variability of collection sites on its chemical and antioxidant properties, as well as the impact of extraction parameters on epicatechin and procyanidin A2 content. The in vitro antibacterial activity against Propionibacterium acnes was also investigated. The leaf samples were collected in different sites of Santa Catarina (Brazil) and in different seasons. The influence of ethanolic grade, drug:solvent ratio, and time of extraction on the chemical markers and the antioxidant activity (DPPH) were analyzed, using Bayesian generalized linear models, based on the Integrated Nested Laplace Approximation and multivariate analysis of principal component. The best extraction conditions were 70 °GL ethanol, 5% of drug:solvent, and 5 h of maceration. The solvent represented the greatest impact factor on the chemical markers. Neither site nor season of collection showed influence on chemical markers. In addition, the leaves extract displayed activity against Propionibacterium acnes at 5 mg/ml. Graphical abstract