Effect of germination conditions on antioxidant activity of germinated brown rice

This investigation aims to study the effects of germination conditions and extraction solvents on total phenolic content and antioxidant activities of Chiang Phatthalung a recommended rice cultivar in Southern Thailand. Chiang Phatthalung (Oryza sativa L.) was germinated by soaking in tap water at 25, 30, 35 or 40°C for 24 h and then dried and powderised before subjected to extract with various solvents and analyses. Amongs all extraction solvents used, including 50% MeOH + 0.1% HC1, water, 25% EtOH, 50% EtOH, 75% EtOH and 95% EtOH, rices extracted with 50% EtOH had highest total phenolic content and antioxidant activities (P < 0.05). It was noticeable that brown rice germinated by soaking in tap water at 25°C had highest total phenolic content and antioxidant activities as determined by DPPH-, ABTS-radical scavenging activity and ferric reducing antioxidant power (P < 0.05). In addition the results suggesting that total phenolic content and antioxidant activities of germinated brown rice were higher than those of brown rice (P < 0.05).