A novel alpha-iso-cubebenol, which has anti-inflammatory effects in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, was isolated from the fruits of Schisandra chinensis. alpha-iso-cubebenol inhibited LPS-induced nitric oxide (NO) and prostaglandin E-2 (PGE(2)) production. Consistent with these findings, alpha-iso-cubebenol also reduced the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 at the protein and mRNA levels in a concentration-dependent manner. alpha-iso-cubebenol also inhibited LPS-induced nuclear translocation of the NF-kappa B p65 subunit. Furthermore, alpha-iso-cubebenol suppressed the phosphorylation of ERK, JNK, and p38 kinase induced by LPS. Since the novel alpha-iso-cubebenol blocked the production of several pro-inflammatory mediators induced by LPS in macrophages, the molecule can be useful material for the development of anti-inflammatory agents against bacterial infections or endotoxin. (C) 2009 Elsevier Inc. All rights reserved.