New Quinolone Compounds from Pseudonocardia sp. with Selective and Potent Anti-Helicobacter pylori Activity: Taxonomy of Producing Strain, Fermentation, Isolation, Structural Elucidation and Biological Activities.

Eight novel quinolones with anti-Helicobacter pylori activity were isolated from the actinomycete Pseudonocardia sp. CL38489. The quinolones were very potent against H. pylori with MICs up to 0.1 ng/ml. The quinolones appear to be specific for H. pylori, since they did not show antimicrobial activity when tested against a panel of other microorganisms.