A new lipoxygenase inhibitor, 6'-hydroxyoxosorbicillinol (1, C14H16O6), was identified from a culture of Penicillium sp. A known compound, oxosorbicillinol (2, C14H16O5), was also isolated. Compound 1 showed an approximately 10 times greater inhibitory effect on soybean lipoxygenase (IC50, 16 µM) than 2 (IC50, 150 µM), and also showed prostaglandin D2 (PGD2) and leucotriene B4 (LTB4) release suppression activity (IC50, 10 µM for PGD2 and 100 µM for LTB4).
