Figure 1: In-vitro DPPH assay of S. aromaticum extract. (a) Bar diagram shows the percentage inhibition of free radicals by S. aromaticum extract in comparison with standard (ascorbic acid). (b) Percentage inhibition of DPPH free radicals by S. aromaticum extract. DPPH standard curve was plotted for five different concentrations of S. aromaticum extract. Concentration was plotted on the x-axis (independent variable) and percentage inhibition of DPPH free radicals by S. aromaticum extract was plotted on y-axis (dependent variable). Absorbance was measured at 517 nm. The obtained regression value was 980 (R2 = 0.920).