Department of Chemistry, Islamic Azad University, Sabzevar Branch
Abstract
In this study, water and ethanol extracts of grape residuum was prepared by ultrasound and percolation extraction methods. The total amount of phenolic compounds present in the extracts was determined by of Folin ciocalteu method, free radical scavenging strength was determined by DPPH method and chelating ability of iron ion was determined by Ferrozine assay. Analysis of variance with SAS program showed that the effect of solvent, time, intensity and interaction [intensity × time] and [intensity × solvent] and [Time × solvent] on the strength of radical scavenging has significant difference in 0.01 (one percent) between the experimental levels. Comparison of means showed that the 50% radical scavenging power (IC50) of ethanol extract is more than aqueous extract. Maximum radical scavenging power for ultrasound extract was observed at 40 minutes sonication and minimum power was observed at 30 minutes sonication. Increase the intensity of ultrasound can reduce radical scavenging power, while its maximum was observed in the intensity of 20% and its minimum in the intensity of 40 percent.
)