ANTIOXIDANT ACTIVITY OF TRITERPENE GLYCOSIDE (CORTUSOSIDE A) FROM CORTUSA MATTHIOLI L. PLANT

Abstract

The antioxidant activity of triterpene glycoside, first isolated from the aboveground part of the plant Cortusa matthioli L. and identified as β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→2)]-α-L-arabinopyranoside-(1→3)-13β,28-epoxyolean-30-al-3β,16α-diol (cortusoside A), is studied. Tests for the ability of cortusoside A to bind 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals did not reveal any activity of this compound. However, in experiments to study the ability to chelate Fe2+ ions, its sufficiently high iron chelating activity was found, which was only 2.24 times lower compared to the powerful Fe2+ chelator dipyridyl. The EC50 values for cortusoside A and dipyridyl were 0.417±0.057 and 0.186±0.018 mM, respectively. Literature analysis has shown that the structural analogue of cortusoside A, saxifragifolin B, has a much weaker iron chelating ability (13,4 times) compared to the standard Fe2+ EDTA-Na2 ion chelator, as well as a weak ability to bind free radicals of DPPH compared to the reference antioxidants – catechin and ascorbic acid (50 and 32 times, respectively). Despite the structural identity of the molecules cortusoside A and saxifragifolin B, low radiculopathy activity cortusosoide A may be due to differences in the structure of these substances (optical or geometric isomerism), as well as different methods were used in its definition.