5-LIPOXYGENASE AND CYCLOOXYGENASE-1 INHIBITORY ACTIVE COMPOUNDS FROM ATRACTYLODES LANCEA

Lipophilic extracts of Atractylodes lancea rhizomes exhibited potent i nhibitory activities in 5-lipoxygenase [IC50 (5-LOX) = 2.9 mu g/mL (n- hexane extract)] and cyclooxygenase-1 [IC50 (COX-1) = 30.5 mu g/mL (n- hexane extract)] enzymatic assays. Bioactivity-guided fractionation of the n-hexane extract led to the isolation of a new compound atractylo chromene (1), a potent inhibitor in both test systems [IC50 (5-LOX) = 0.6 mu M, IC50 (COX-1) = 3.3 mu M] Also obtained was -octadienyl]-6-me thyl-2,5-cyclohexadiene-1,4-dione (2), which showed a selective inhibi tory activity against 5-LOX [IC50 (5-LOX) 0.2 mu M, IC50 (COX-1) 64.3 mu M]. The sesquiterpene atractylon (3) and the coumarin osthol (4) tu rned out to be moderate but selective 5-lipoxygenase inhibitors. Atrac tylenolides I (5), II (6), and III (7) showed no significant inhibitor y effects for either enzyme. Structures were established by spectral d ata interpretation.