Fig 1: MAO-A enzyme inhibition dose–response curve for (A) Pharmacologically active compounds (RA, rosmarinic acid; SEN, sinensetin; and EUP, eupatorin) and (B) Ethanol extract of Orthosiphon stamineus leaves (EtOH 95% and 50%). The data are presented as the mean ± SD of three replicates of each concentration (n = 3). IC50 values were calculated using non-linear regression (4-parameter logistic curve).