FLAVONOIDS FROM ASTRAGALUS GENUS

In this review our main focus is on flavonoid groups which are one of the main active constituents found with other active constituents like saponins and polysaccharides, while poisonous groups are nitro-compounds, indolizidine alkaloids and the seleniferous derivatives in Astragalus genus. It is well established fact that flavonoid possess many biological activity such as antiallergic, anti-inflammatory, antitumor, antiviral, antioxidant anticancer including anticarcinogenic and prodifferentiative activities. Many flavonoids, including those which are phytoalexins, provide plants with a defense against viral infections. The estrogenic action of many isoflavones is well known and mixtures of flavonoids are commonly used commercially to reduce capillary fragility. Astragalus root is a very old and well known drug in traditional Chinese medicine and have been used to improve resistance to infections and to aid in immunological disorders and viral infections, and also used as hepatoprotective, heart tonic, nephritis and diabetes. This review reports all flavonoids isolated till date which is  nearly about 131 from 60 species of Astragalus genus; these flavonoid are further characterized and classified into flavones, flavonols, flavanones, flavan-4-ols, isoflavones, isoflavans, petrocarpans and miscellaneous