Catalase

Catalase is a common enzyme that is found in nearly all living organisms that are exposed to oxygen, such as bacteria, plants, and animals. It catalyzes the decomposition of hydrogen peroxide, a harmful substance, into water and oxygen, which are harmless. This way, catalase protects the cells from oxidative damage by reactive oxygen species (ROS), which can cause mutations, aging, and diseases.  Catalase is especially abundant in the liver, where it helps to detoxify the blood.