By Emily Hart, Taylor Munger, Sasha Murphy

Faculty Mentor: Sarah Smith

Abstract

This experiment aims to determine the concentrations of epigallocatechin-3-gallate (EGCG) and ascorbic acid (Vitamin C) in a variety of commercially available bottled tea brands. EGCG is a potent catechin commonly found in tea leaves that has shown preventative effects against cancer and cardiovascular disease caused by harmful free radicals. It is hypothesized that brands with higher Vitamin C content will demonstrate higher EGCG concentrations due to the presumed stabilizing effect of Vitamin C on catechin degradation. As part of the method protocol, standard solutions ranging from 10 µg/mL to 320 µg/mL will be prepared in methanol using volumetric glassware, with corresponding molarities determined. Analysis will involve the dissolution of the tea samples in methanol, followed by centrifugation and HPLC analysis using a reversed-phase column. Method validation will encompass parameters such as linearity, range, limit of detection, and limit of quantitation. A comparison of the determined concentrations of EGCG and Vitamin C with the nutritional labels of the tea samples will subsequently be performed, providing insights into the accuracy and reliability of the analytical method. Quantitative comparisons will be made both between brands of black tea and between green and black teas of the same brand