Antioxidant activity and improvement in the yield of antioxidant compounds

Abstract

Antioxidants are the first line of defense against free radical damage and are critical for maintaining optimum health and well-being. Exposure of biological system to xenobiotics, pollutants, ionizing radiations or UV light, and development of certain pathological conditions consequently increases production of oxyradicals. Oxygen radicals such as superoxide anions, hydroxyl radicals, and hydrogen peroxide are cytotoxic and give rise to tissue injuries. According to various evidences, compounds derived from natural sources are helpful in providing protection against free radicals. There is an increasing demand for natural antioxidants due to safety concerns for synthetic antioxidants, in addition to increasing consumer preference for natural products, clean label, and less usage of food additives in food products. Therefore, an attempt has been made to review novel techniques such as microwaveassisted extraction and pressurized liquid extraction for recovery of high yield of antioxidant compounds with less solvent and time consumption and also some in vitro and in vivo models for determining antioxidant properties of products from medicinal plants.