Solvent extraction of antioxidants from tamarind seed coat

Seed coat of tamarind (Tamarindus indica L) cultivated in Thailand was extracted by three organic solvents at different temperatures, with and without sonication. Antioxidant properties, including 1,1-diphenyt-2-picrylhydrazyl (DPPH) radical scavenging activity, reducing power, and ferrous ion chelating ability, were investigated. Ultrasonic extraction at 40 degrees C, using methanol or ethanol as the extracting solvent, was found to posses strong antioxidant activities.