Abstract

Free radicals produced on exposure to sunlight, Xrays, ozone, tobacco smoke, automobile exhaust, environmental pollutants, and by several other physiological processes, are highly reactive and can damage nucleic acids, proteins, lipids and carbohydrates that subsequently affect the immune functioning causing degenerative diseases. In a normal cell there is an appropriate balance between prooxidant and antioxidants. When the level of pro-oxidants is increased in comparison to antioxidant, this state is termed as oxidative stress (OS). It is imposed on the cells due to increase in oxidant generation and decrease in antioxidants protection, resulting in failure in repair of oxidative damage. Exposure to pathogens, inappropriate lifestyle, excessive exercise, and by-products of normal metabolism are also contributing factors to OS. Reactive oxygen species are also responsible for DNA (deoxyribose nucleic acid) damages resulting in mutagenic changes that are responsible for several diseases. Oxidative stress deregulates the cellular functions leading to neuro-degenerative diseases, gastroduodenal pathogenesis, some kinds of cancer, cataracts, premature aging, inflammation, cardiovascular, and metabolic dysfunction. It may also influence the immune system either by hyper-excision to cause autoimmune disorder, or suppress it, resulting in the high susceptibility to infection. Owing to increased safety concerns about synthetic antioxidants, exploitation of safer antioxidants based on natural origin is the focus of research nowadays, and the present study has hallmarked the same. In this manuscript, therapeutic worth of various constituents including antioxidants of natural products viz. garlic, soyabean, gooseberry, broccoli, spirulina and aloevera have been delineated precisely.