Effect of gamma-irradiated chitosan to enhance antioxidant activity of Khai Mod Rin germinated brown rice

Khai Mod Rin has been certified as NSRC95001-1-3 grower community enterprise in Hua Sai district, Nakhon Si Thammarat, Thailand. The effect of γ-irradiated chitosan concentrations and soaking time was examined for a proper conditions of germination. The standard phytochemical screening method and quantitative analysis of DPPH, ABTS, FRAP, total phenols and flavonoids, were also evaluated. The Khai Mod Rin germinated brown rice (KMR-GBR) with the best antioxidant activity and highest in total phenolic and flavonoid contents was produced after exposure to γ-irradiated chitosan (500 ppm concentration) at room temperature for 36 h germination. Phytochemicals including alkaloids, terpenoids, coumarin, flavonoids and cardiac glycosides were detected still the same as germination in water and pure chitosan. Evidently, γ-irradiation on chitosan can be used to enhance antioxidant activity during brown rice germination, which is a potential source of natural antioxidants for food processing.