Newly isolated marine Bacillus pumilus (SP21): A source of novel lipoamides and other antimicrobial agents

A screening of marine bacteria for antimicrobial activity resulted in the isolation of Bacillus pumilus (SP21.) from a sediment sample collected in the Bahamas. A bioassay-guided fractionation led to the isolation of five surfactin analogs, glycocholic acid, amicoumacins A and B in addition to three new compounds named lipoamides A-C. The chemical structure of all the bioactive compounds was elucidated using spectroscopic methods including 2D NMR and MS. The antimicrobial activity of each compound was evaluated against a panel of pathogens and is reported herein.