Natural products and their antioxidant potentialAuthor(s): Anju Agrawal, Bechan Sharma
A natural product is a chemical compound or substance produced by a living organism found in nature that usually has a pharmacological or biological activity for use in pharmaceutical drug discovery and drug design. Natural products have been the basis of treatment of human diseases and many higher plants contain novel metabolites with antimicrobial and antiviral properties. As an alternative medicine, people derived therapeutic materials from thousands of plants; however discovering medicines or poisons remains a vital question. Since reactive oxygen radicals play an important role in genesis of numerous human disease processes, antioxidants derived from consumable fruits, vegetables, spices and beverages have received considerable attention. The antioxidants protect our body systems from free radicals mediated damage at the cellular and molecular levels. The pool of free radicals production in our body stems mainly from themitochondrial activity but the environmental factors such as xenobiotics, pollutants and other stressors also contribute in it enormously. This phenomenon generates imbalance between the oxidants (free radical species, FRS) and the innate antioxidants; a condition called as oxidative stress. Oxidative stress leads to onset of numerous disease processes including cancer, heart, lung, brain and kidney associated diseases, cell death and aging. Apart from the best-known antioxidants such as vitamins A, C and E, and the mineral selenium, some flavonoids (secondarymetabolites) and vitamin precursors synthesised by plants are required to be taken from outside to establish the balance by quenching the excess FRS. The present review presents a comprehensive account of updated information available on natural products containing antioxidant potential with therapeutic implications.