Detection of phenols content and antioxidant activity of four grains

To investigate the phenols profiles (soluble and insoluble polyphenol, ferulic acid and flavonoids) as well as their antioxidant activities in uncooked whole grains. The results demonstrated that corn had the highest total phenolic content (49.13±3.39) mg/100g of the grains tested, followed by rice (23.49±3.37) mg/100g, wheat (18.60±3.52) mg/100g and oats (13.92±4.56) mg/100g. The major portion of phenolics in grains existed in the bound form (95.54% in corn, 90.76% in rice, 89.46% in wheat, and 86.85% in oats) . Ferulic acid was the major phenolic compound in grains tested, with soluble and insoluble ferulic acids present in the ratio 1∶34 in corn, 1∶33 in rice, 1∶17 in wheat, and 1∶5 in oats. The insoluble polyphenol in corn had the highest superoxidized anionic radicals scavenging activity (95.01%±2.25% ) and highest antioxidant activity towards the edible oils (34.23±2.61) mmol/kg.