Dammarane Triterpene Saponin fromBacopa monnieraas the Superoxide Inhibitor in Polymorphonuclear Cells

Abstract

The hydroalcoholic extract of the whole plant of Bacopa monniera Wettst. (Scrophulariaceae), exhibited an inhibitory effect on superoxide released from polymorphonuclear (PMN) cells in the nitroblue tetrazolium (NBT) assay. The major saponin bacoside A₃ was found to be responsible for this effect in the herb. This compound showed 85, 91.66, 91.66, and 83 % inhibitions of NBT reduction at the concentrations of 200, 100, 50, and 25 μg/ml, respectively, with an IC₅₀ value of 10.22 μg/ml. These inhibitory effects were compared with those of the standard positive controls, quercetin and ascorbic acid with IC₅₀ of 111 and 14.16 μg/ml, respectively. Another major saponin bacopasaponin C was found to be much less potent as compared to bacoside A₃ whereas the remaining two mixtures of saponins were found to be inactive.