Effect of commercially available green and black tea beverages on drug-metabolizing enzymes and oxidative stress in Wistar rats

•Commercially available green and black tea beverages modify drug-metabolizing enzyme (DME) activity in liver and lungs.•Green and black tea beverages increase glutathione levels in liver and lungs.•Tea beverages reduce pregnane X receptor and increase nuclear factor-erythroid 2 p45-related factor 2 binding to DNA.•The green tea beverage is more effective for reducing oxidative stress in lungs than the black tea beverage.