Valorization of Camellia Sinensis Flowers in Cosmetic and Pharmaceutical Applications: Optimization of Microwave-Assisted Glycerin Extraction

This study aims to valorize tea flowers through microwave-assisted extraction using glycerin. The total phenolic content of the tea flowers was optimized. The total phenolic content, total flavonoid content, antioxidant activities, and bioactive compounds of the tea flowers obtained via microwave-assisted extraction with glycerin were compared with those obtained via maceration with glycerin. The cytotoxicity and cellular antioxidant activities of the extract obtained via microwave-assisted extraction with glycerin were analyzed in fibroblast cells. The selected concentration of the extract obtained via microwaveassisted extraction with glycerin was incorporated into the formulation and its short-term stability was determined. Under the optimal conditions of extraction temperature (53 degrees C), solid/liquid ratio (1:28 g/mL), and solvent concentrations (40% w/v), the total phenolic content was 43.20 +/- 0.94 mg of gallic acid equivalents /g sample. Compared to the samples extracted via maceration with glycerin, those extracted via microwave-assisted extraction with glycerin had higher values of total phenolic content, total flavonoid content, and antioxidant activities. Epigallocatechin gallate, epigallocatechin, caffeine, and various types of catechins were the most abundant bioactive compounds detected by liquid chromatographic-triple quadrupole mass spectrometry in the extract obtained via microwave-assisted extraction with glycerin. Furthermore, the extract of 1-7.5 mg/ mL was effective in preventing oxidative damage to fibroblast cell line. Thus, the tea flower extract obtained via microwaveassisted extraction with glycerin exhibit antioxidant activities that can be directly incorporated into a formulation that can be used in cosmetic and pharmaceutical applications. [GRAPHICS] .