The hexane fraction of Cordiera sessilis, a native species of the Cerrado, presented moderate antibacterial activity against the oral aerobic Streptococcus mitis and S. sanguinis. This fraction was refracted in a chromatographic column providing subfractions that were selected for spectrometric assay in GC-MS where possible to verify the presence of fatty acids; methyl-14-methylpentadecanoate, palmitic acid, stearic, behenic acid, melissic acid and the steroids campesterol, stigmasterol and sitosterol.