The soraphens: a family of novel antifungal compounds from Sorangium cellulosum (Myxobacteria). I. Soraphen A1 alpha: fermentation, isolation, biological properties.

An antifungal activity was detected in the culture broth of Sorangium cellulosum (Myxococcales), strain So ce26. The activity was excreted into the supernatant during the log and early stationary phase. The active substance was quantitatively bound to XAD absorber resin added to the medium at the beginning of the fermentation. The new secondary metabolite was called soraphen and is of special interest to plant disease control for its inhibitory activity against numerous phytopathogenic fungi.