Abstract:Two bioactive compounds were isolated from the crude acetone extract of the mycelium of Streptomyces luteogriseus ECO 00001 by bioassay-guided and various chromatographic procedures, they were identified as macrolide antibiotic oligomycins C and A by various spectral analysis. Their antifungal activities against five plant pathogenic fungi were evaluated in vitro by using methods of spore germination inhibition and mycelial growth inhibition. When the concentrations of oligomycins C and A were respectively 15μg/mL and 5μg/mL, their spore germination inhibition rates to Botrytis elliptica and Colletotrichum liliacearum of Lilium longiflorum, Alternaria alternate, Pyricularia grisea and Fusarium moniliforme were 100%. Their diameters of inhibition circle against the above five plant pathogenic fungi were all above 10mm when the concentrations of oligomycins C and A were respectively 100μg/mL and 50μg/mL. The inhibited activities against five plant pathogenic fungi of compound II were stronger than those of compound I.