Decrease in concentration of free catechins in tea over time determined by micellar electrokinetic chromatography

Cancer chemoprevention is a new and important medical science and much interest has been focused on catechins, not only for their antioxidant activity, but also because of their known antimutagenic and antitumorigenic properties. Green tea and black tea, which are among the most popular beverages consumed worldwide, contain many different catechins. Due to the instability of catechins in solutions with neutral or basic pH values the concentrations of catechins in tea decrease in time. In this presentation we used micellar electrokinetic chromatography to determine the real concentration of catechins between 0 and 60 min after the tea was brewed.