| 摘要 |
PURPOSE:To obtain an antibiotic substance WK-1875 active against phytopathogenic fungi and useful as an agricultural chemical by culturing a microbial strain belonging to genus Streptomyces and capable of producing antibiotic substance WK-1875 and treating the culture product. CONSTITUTION:A microbial strain belonging to genus Streptmyces and capable of producing antibiotic substance WK-1875 (FERM P-9859) is cultured in a proper medium under aerobic condition e.g., by shaking culture or submerged culture under aeration and agitation, at 20-40 deg.C and pH4-9 for 1-7days to accumulate the antibiotic substance WK-1875 inside and outside of the cell. The culture product is separated by centrifugal separation, the filtrate is adsorbed to a porous polymer resin, etc., and eluted, and the eluate is concentrated, dried and purified to obtain the objective antibiotic substance WK-1875 having the following properties. Elemental analysis (measured value, %), C 64.7+ or -1.0, H 9.1+ or -0.3; specific rotation, -12.1 deg. (c=0.5, methanol); melting point, 116-119 deg.C; ultraviolet absorption, infrared absorption and proton nuclear magnetic resonance spectra, exhibiting specific respective patterns; solubility, soluble in methanol, ethanol, ethyl acetate and CHCl3 and insoluble in water and n- hexane; molecular formula C40H68O12. |
