Determination of antimutagenic ability of tea extract by Ames test

Abstract

Tea is one of the most popular beverages and the consumption of tea is increasing nowadays. Therefore, the objective of this project was to quantify total polyphenol content and catechin profile. Moreover, it was aimed to study and compare the effects of tea produced by different process on modulation of mutagenicity of mutagen in various tea cultivars. There are 5 types of tea; Green tea from Assam Tea and Oolong tea No.12 cultivars (non-fermented), Oolong tea from Oolong tea N0.12 cultivar (semi-fermented), Black tea from Assam Tea cultivar (fermented) and Lemongrass tea. Wistar rats were treated with tea extract for 1 day before IQ gavage (5 mg/kg). Two levels of tea extract were 1.11 g/kg/day and 111 mg/kg/day. The urine was collected to determine the antimutagenic ability of tea extracts by Ames test using Salmonella typhimurium strain YG1024. The characteristics of tester strain were validated namely histidine requirement, mutation of cell wall, presence of R-factor and bacterial viability before applying in Ames test. The results confirmed that the bacteria have all characteristics required. Furthermore, analysis of total polyphenol content and catechin profile in tea samples revealed that Green tea from Assam Tea cultivar has the highest total polyphenol, total catechin content, Epigallocatechin (EGC), Epicatechin (EC) and Cathechin (C) whereas lemongrass tea contains the least polyphenol content.