Study of antioxidative activity in four kinds of cultivated rice grains of Mazandaran province (Iran)

Abstract

Antioxidants in rice food are important for human health. However, the level of antioxidative activity of different rice grains (Oriza sativa L.) which is the staple food in Mazandaran province of Iran and is the main agricultural product exported to other countries has not previously been reported. In this preliminary investigation, the antioxidative activity in vitro of the alcoholic extract from four different kinds of rice grains have been determined by ABTS/methemoglobin method compared with Trolox, an vitamin E analog. It was found that the antioxidative activity (TEAC) as μmol per g of dry rice varied from the highest to the lowest as the followings: Tarom rice (20.22), Khazar rice (9.44), Neda rice (8.78) and Sadri rice (1.33), respectively. TEAC is distinguishly the highest in Tarom rice and remarkedly high in Khazar rice. This property may be due to the high contents of rice anthocyanins, vitamin E, tocotrienols and oryzanol. The functional chemistry, nutritional value and health benefits of antioxidants contained in rice grains, rice bran and their products should be intensively studied and characterized for their ingredients and stability. Further development for the value addition of rice as diet supplements and maximum health benefits is needed. © 2006 Asian Network for Scientific Information.