MALTOPHILIN - A NEW ANTIFUNGAL COMPOUND PRODUCED BY STENOTROPHOMONAS-MALTOPHILIA R3089

Strains of Stenotrophomonas maltophilia R3089, isolated from the rhizo sphere of rape plants (Brassica napus L.), produced a novel antifungal compound, named maltophilin, which inhibited the growth of various sa prophytic, human-pathogenic and phytopathogenic fungi but was inactive against Gram-positive and Gram-negative bacteria. Maltophilin is a no vel macrocyclic lactam antibiotic with a molecular mass of 510 mu. The compound was isolated from the culture filtrate by ethyl acetate extr action and gel filtration on Sephadex LH20 and purified by preparative HPLC on reversed phase. The structure of maltophilin was elucidated b y electrospray mass spectrometry and H-1 and C-13 NMR spectroscopy.