Hydroxylation is a
chemical process that introduces a
hydroxyl group (-OH) into an
organic compound. In
biochemistry, hydroxylation reactions are often facilitated by
enzymes called hydroxylases. Hydroxylation is the first step in the oxidative degradation of organic compounds in air. It is extremely important in detoxification since hydroxylation converts lipophilic compounds into water-soluble (hydrophilic) products that are more readily excreted. Some drugs (e.g.
steroids) are activated or deactivated by hydroxylation.