1996 Volume 49 Issue 7 Pages 631-634
Selective growth inhibition against IL-6 dependent cells was detected in fermentation extracts of a fungal strain FO-4649 which was characterized as Sporothrix species. An active metabolite (1) termed chlovalicin was isolated together with ovalicin and two other ovalicin derivatives (compounds 3 and 4). Chlovalicin, a ovalicin derivative with a chlorinated methylene moiety at the C-1 position of the cyclohexane ring, dose-dependently inhibited the growth of IL-6 dependent MH60 cells (IC50, 7.5μM) in the presence of 0.2U/ml IL-6 and, to a lesser extent, the growth of B16 melanoma cells (IC50, 38μM). Among the other three compounds, only ovalicin showed inhibitory activity (IC50, 27μM) against MH60 cells. These four compounds did not show any antimicrobial activity at a concentration of 1000 μg/ml.
