Comparative studies on the antioxidant, anticancer and anti-inflammatory activities of green tea, orthodox black tea and CTC black tea.

Tea is a natural dietary supplement rich in polyphenols and based on the manufacturing process, their polyphenol content also varies. In the present study, we have compared the in vitro antioxidant, anticancer and anti-inflammatory activities of green tea (GT), orthodox black tea (oBT) and CTC black tea (cBT). The analysis was carried out in 50:50 ethanol:water extracts. The total antioxidant capacity, total polyphenol content and free radical scavenging activity were found to be high in GT samples. HPLC profiling indicated a higher percentage of polyphenols like catechin, epicatechin, epigallocatechin and epigallocatechin-gallate in GT when compared to other samples. The comparison of the anticancer potential was done in breast cancer MDA MB-231 cells and it was found that GT has a higher percentage of cell growth inhibition than oBT and cBT. Anti-inflammatory effects were done in LPS stimulated RAW264.7 macrophage cells and here also GT showed maximum effects. This was confirmed by the lower production of iNOS, reduced level of ROS generation and proinflammatory cytokines such as MCP-1, IL-1ɑ, and IL-6 by GT. To conclude, the order for the biological effectiveness of different teas tested is in the order GT > oBT > cBT.