New peptide antibiotics LI-F03, F04, F05, F07, and F08, produced by Bacillus polymyxa. I. Isolation and characterization.

Abstract

A strain of Bacillus polymyxa produced a new peptide antibiotic complex, named LI-F, composed of more than ten components. The components, antibiotics LI-F03, F04, F05, F07, and F08 were isolated from the complex by reversed phase HPLC. They are active against fungi, yeasts, and Gram-positive bacteria. The fast atom bombardment mass spectra revealed that the individual isolated antibiotics are still mixture of two homologous components, being very difficult to separate from each other.