Lichenysins G, a novel family of lipopeptide biosurfactants from Bacillus licheniformis IM 1307: Production, isolation and structural evaluation by NMR and mass spectrometry

A series of 9 lactonic lipopeptide biosurfactants was isolated from Bacillu s licheniformis IM 1307 as representatives of the lichenysin group and we p ropose to name them lichenysins G. They were recovered from the culture med ium as complex mixtures of molecules having different peptide sequences and different structures of P-hydroxy fatty acids. Their separation was achiev ed by a reversed-phase HPLC method leading to eight well-separated compound s. The complete structure of individual isoforms was proposed following the results of amino acid and fatty acid analysis, LSI-MS and 2D NMR spectrosc opies. Compared to surfactin, lichenysins G are at least 10 fold more effic ient biosurfactants.