Abstract

Oxidants or reactive oxygen species are produced in our body during aerobic metabolism leading to many diseases such as cancer, cardiovascular diseases etc. Antioxidants are the chemicals that neutralize these oxidants. Natural antioxidants are the secondary metabolites of phytochemicals and are preferred over synthetic antioxidants, which are found to impose side effects. A review has been done on the effect of oxidants on human health and their neutralization by natural antioxidants. Major natural antioxidants and their plant sources, different recovery processes for antioxidants from plant matrices and the advantage of indirect supercritical fluid extraction over other processes are presented.

Key words: Free radical, secondary metabolites, oxidative stress, recovery processes, process parameters.