Phytochemical Characterization and Chemical Stability of Green Tea Extract

Camellia sinensis leaves tea has been one of the most consumed drinks in worldwide. Green tea has been consumed regularly by the world population, including for medicinal purposes. From a nutritional point of view, phytochemical analyzes is essential to know the composition and concentration of compounds in green tea, as well as the stability of these components. In this study the phytochemical properties and chemical stability of green tea were evaluated. A sample, widely sold in Brazil, was submitted to extraction, following of analyzes for detection of the main compounds and evaluation of the stability of green tea extract preparations by HPLC. As result, the green tea extract presented caffeine (34.4%), epicatechin gallate (11.9%), and epigallocatechin (5.8%) as main identified compounds in its composition. During the four weeks of evaluation, the main metabolites presented small decomposition rate (2.4 to 2.9%). In addition, the phytochemical analysis revealed the presence of several secondary metabolites in their composition (alkaloids, glycosides, saponins, tannins, terpenoids, caffeine and flavonoids). This demonstrates that green tea extract has compounds with properties that bring health benefits but also as it contains other secondary metabolites, and its therapeutic use should be carefully evaluated.