Essential oils are volatile aromatic oily liquids which are identified by a strong smell and are produced by aromatic plants as secondary metabolites. Essential oil can be isolated using a number of isolation methods. The aromatic plants and spices are commonly used in phytotherapy and mostly related to various activities of their essential oils, such as antimicrobial, antioxidant, antifungal spasmolytic, carminative, hepatoprotective, antiviral and anticarcinogenic activities.
The increased discoveries in herbs and spices as sources of natural antioxidants have initiated researchers to look for natural antioxidants with low cytotoxicity. The free radicals which cause oxidative stress are believed to play an essential role in human health. They are produced in body system in the form of reactive oxygen species (ROS) which can be obtained from the environment. These free radicals cause harm to the components of the cell resulting in cellular and metabolic disruption such as cardiovascular diseases, inflammation inflammation and cancer.