Dallas-based Purpose Tea markets an R-.T.-D. purple tea beverage, which is made from leaves grown exclusively in Kenya. “Purple tea leaves contain 15 times more anthocyanins than blueberries and have a greater degree of antioxidant activity than either green or black tea,” said Chi Nguyen, founder and chief executive officer. “Consumers are becoming more engaged with their teas and want to learn more and more about where their teas come from, how they are harvested and manufactured, how the product supports the livelihoods of those making it, and how friendly the product is to the environment.”