Antioxidants are important for plant and animal's life or health. These are the substances that protect them from the damage produced by unstable molecules called as free radicals. There are various types of antioxidants to be reported both natural as well as synthetic such as melatonin, Vitamin C, glutathione, tocopherols and tocotrienols, BHA and BHT, etc. A new antioxidant 5-O-[6˝-(3- hydroxy-3methyl glutarate) β-D-glucodise was found while studying bioactive antioxidants from plant foods for nutraceutical product development. Antioxidants have been used for increasing shelf life of various food products including extruded product. Antioxidants, their beneficial advantages and the effect of extrusion on antioxidants were reviewed and found to be effective in increasing the shelf life. This review article discusses recent patents, presents importance of antioxidant, phytochemicals and effect of process of extrusion on antioxidants.