Abstract
The radical scavenging activity of the Japanese late-fermented black tea, Toyama Kurocha, was investigated. The activity was determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method, and its radical scavenging activity was found to be lower than that of green tea. Dried leaves of Toyama Kurocha were extracted in boiling distilled water for 10 min, the resulting extract was fractionated in the usual way, and the strongly acidic fraction was purified by silica gel column chromatography and HPLC. Five peaks of phenolics and 4 unknown peaks were detected by HPLC, and the main phenolics component in Toyama Kurocha was believed to be a gallic acid. Gallic acid has the highest DPPH radical scavenging activity.
