Inhibition of cyclooxygenase (COX) enzymes by compounds from Daucus carota L. Seeds.

Cyclooxygenase (COX) enzymes inhibitory assay directed investigation of Daucus carota seed extracts resulted in the isolation and characterization of compounds, 2,4,5-trimethoxybenzaldehyde (1), oleic acid (2), trans-asarone (3) and geraniol (4). Compounds 1-4 showed 3.32, 45.32, 46.15, and 3.15% of prostaglandin H endoperoxide synthase-I (COX-I) inhibitory activity and 52.69, 68.41, 64.39 and 0% prostaglandin H endoperoxide synthase-II (COX-II) inhibitory activity, respectively at 100 mg mL(-1). Compound 1 showed selectivity towards COX-II enzyme inhibition at 100 microg mL(-1). The COX-II/COX-I ratio for compound 1 was 17.68 at 100 microg mL(-1) compared to solvent control. Ibuprofen, Naproxen, Aspirin, Celebrex and Vioxx at concentrations of 2.06, 2.52, 180, 1.67 and 1.67 microg mL(-1), respectively, gave COX-II/COX-I ratios of 1.13, 0.92, 0.24, 16 and 75, respectively. The inhibition of COX-II enzymes by compounds 1 at 100 microg mL(-1) was significant when compared to Aspirin, Ibuprofen, Naproxen and Celebrex at concentrations studied.