A fungal strain FKI-2136 identified as genus Aspergillus was found to produce potentiators of imipenem activity against methicillin-resistant Staphylococcus aureus (MRSA). Two new compounds designated stemphones B and C were isolated along with a structurally related known compound cochlioquinone D from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography and preparative HPLC. These compounds have a common tetracyclic quinone skeleton. Stemphone C potentiated imipenem activity against the MRSA 512 fold by decreasing MIC value of imipenem from 16 mg/ml to 0.03 mg/ml.

During our screening for microbial inhibitors of lipid droplet accumulation in macrophages, a new compound designated spylidone was isolated along with two structurally related known compounds, PF1052 and vermisporin, from the fermentation broth of Phoma sp. FKI-1840 by solvent extraction, silica gel column chromatography, ODS column chromatography and preparative HPLC. From the structure elucidation, spylidone has a spiro ring containing 2,4-pyrrolidinedione. Among the three compounds, only spylidone was found to inhibit lipid droplet accumulation in macrophages at 10ϳ50 mM without any cytotoxic effect.

Other bioactive products U 1300 Spylidone, a Novel Inhibitor of Lipid Droplet Accumulation in Mouse Macrophages Produced by Phoma sp. FKI-1840. -Spylidone (I) is isolated from the fermentation broth of Phoma sp. FKI-1840 along with the 2 structurally related known compounds PF1052 and vermisporin. (I) inhibits lipid droplet accumulation in macrophages. -(KOYAMA, N.; NAGAHIRO, T.; YAMAGUCHI, Y.; OHSHIRO, T.; MASUMA, R.; TOMODA*, H.; OMURA, S.; J. Antibiot. 58 (2005) 5, 338-345; Sch. Pharm. Sci., Kitasato Univ., Minato, Tokyo 108, Japan; Eng.) -M. Bohle 47-210

Other bioactive products U 1300 Stemphones, Novel Potentiators of Imipenem Activity Against Methicillin-Resistant Staphylococcus aureus, Produced by Aspergillus sp. FKI-2136. -Two new compounds, stemphone B (Ia) and C (Ib), are isolated from the fermentation broth. The taxonomy of the producing strain, the fermentation, isolation, structure elucidation, and biological properties are described. (Ib) potentiates imipenem activity against the MRSA 512 fold. -(KOYAMA, N.; NAGAHIRO, T.; YAMAGUCHI, Y.; MASUMA, R.; TOMODA*, H.; OMURA, S.; J. Antibiot. 58 (2005) 11, 695-703; Sch. Pharm. Sci., Kitasato Univ., Minato, Tokyo 108, Japan; Eng.) -H. Haber 19-208