A New Iridoid Compound Isolated from Aerial Parts of Actinidia polygama and Determination of its Antioxidant Activity

Abstract

A new iridoid named as 1-keto isodehydroiridodiol (1) was isolated from the methanolic extract of the aerial parts of Actinidia polygama Miq. along with nine known compounds (2-10). The chemical structure of the isolated compounds was elucidated on the basis of NMR and MS spectroscopic data. All these compounds were evaluated for their free radical scavenging activities through DPPH and ABTS assays. 1-keto isodehydroiridodiol compound was found to be moderate antioxidatnt agent showing IC50values of 89.7 +/- 2.6 and 129.6 +/- 3.2 mu M in DPPH and ABTS assays, respectively. While 5,7-dihydroxychromone compound expressed the best antioxidant activity showing an IC50 value of 60.3 +/- 0.5 mu M followed by kaempferol having IC50 of 67.2 +/- 0.9 in DPPH assay.