Isolation of Biosurfactant Producing Bacteria from Oil Reservoirs

Biosurfactants or surface-active compounds are produced by microoaganisms. these molecules reducesurface tension both aqueous solutions and hydrocarbon mixtures. in this study, isolation and identification ofbiosurfactant producing bacteria were assessed. the potential application of these bacteria in petroleumindustry was investigated. samples (crude oil) were collected from oil wells and 45 strains were isolated. toconfirm the ability of isolates in biosurfactant production, haemolysis test, emulsification test andmeasurement of surface tension were conducted. we also evaluated the effect of different ph, salinityconcentrations, and temperatures on biosurfactant production. among importance features of the isolatedstrains, one of the strains (no.4: bacillus.sp) showed high salt tolerance and their successful production ofbiosurfactant in a vast ph and temperature domain and reduced surface tension to value below 40 mn/m.this strain is potential candidate for microbial enhanced oil recovery. the strain4 biosurfactant componentwas mainly glycolipid in nature.