Antioxidant and Antibacterial Activities of Several Fractions from Crescentia cujete L. Stem Bark Extract

This research was conducted to determine antioxidant and antibacterial activities of several fractions from Crescentia cujete L. stem bark extract. The powdered stem bark of this plant was extracted by ethanol solvent and then separated by liquid-liquid extraction. The results of this separation were n -hexane, dichloromethane, ethyl acetate, and water fractions. Antioxidant compounds were identified by Thin Layer Chromatography (TLC)–autographic assay using 0.02% 1,1-diphenyl-2-picrylhydrazyl (DPPH) solution. Antioxidant activity was analyzed using DPPH method, while antibacterial activity was evaluated using TLC-bioautographic and agar disc diffusion methods. The results showed that antioxidant compounds were found in all fractions, with the highest chemical constituents was in dichloromethane fraction. The antioxidant activity of dichloromethane fraction was the highest of all fractions with IC 50 value of 95.83±19.64 µg/mL, while ethyl acetate fraction was the lowest activity with IC 50 value of 174.56±21.93 µg/mL. The antibacterial assay indicated that water fraction could inhibit Escherichia coli growth with inhibition diameter zone (IDZ) of 2.36±1.11 mm. However, dichloromethane and ethyl acetate fractions could suppress Staphylococcus aureus growth with IDZs of 2.72±0.30 mm and 4.89±0.72 mm, respectively. Further analysis with TLC-bioautography on dichloromethane fraction showed three compounds with Rf values of 0.88, 0.84, and 0.78 have antibacterial activity.