title: Biosurfactant synthesis by Pseudomonas aeruginosa LBI isolated from a hydrocarbon-contaminated site.
abstract: OBJECTIVE
  Pseudomonas aeruginosa LBI (Industrial Biotechnology Laboratory) was isolated from hydrocarbon-contaminated soil as a potential producer of biosurfactant and evaluated for hydrocarbon biodegradation. The emulsifying power and stability of the product was assessed in the laboratory, simulating water contamination with benzene, toluene, kerosene, diesel oil and crude oil at various concentrations.
  
  
  RESULTS
  Bacteria were grown at 30 degrees C and shaken at 200 rpm for 168 h, with three repetitions. Surface tension, pH and biosurfactant stability were observed in the cell-free broth after 168 h of incubation. The strain was able to produce biosurfactant and grow in all the carbon sources under study, except benzene and toluene. When cultivated in 30% (w/v) diesel oil, the strain produced the highest quantities (9.9 g l(-1)) of biosurfactant. The biosurfactant was capable of emulsifying all the hydrocarbons tested.
  
  
  CONCLUSIONS
  The results from the present study demonstrate that Ps. aeruginosa LBI can grow in diesel oil, kerosene, crude oil and oil sludge and the biosurfactant produced has potential applications in the bioremediation of hydrocarbon-contaminated sites.
  
  
  CONCLUSIONS
  Pseudomonas aeruginosa LBI or the biosurfactant it produces can be used in the bioremediation of environmental pollution induced by industrial discharge or accidental hydrocarbon spills.
authors.affiliation: Department of Biochemistry and Microbiology, Biological Sciences Institute, Universidade Estadual de São Paulo (UNESP), Rio Claro, São Paulo, Brasil.
authors.forename: M P S
authors.initials: MP
authors.lastname: Pirôllo
authors.forename: A P
authors.initials: AP
authors.lastname: Mariano
authors.forename: R B
authors.initials: RB
authors.lastname: Lovaglio
authors.forename: S G V A O
authors.initials: SG
authors.lastname: Costa
authors.forename: V
authors.initials: V
authors.lastname: Walter
authors.forename: R
authors.initials: R
authors.lastname: Hausmann
authors.forename: J
authors.initials: J
authors.lastname: Contiero
mesh_terms: D001673:Biodegradation, Environmental; D001709:Biotechnology / Q000379:methods; D006838:Hydrocarbons / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D010578:Petroleum / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000254:growth & development / Q000378:metabolism*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000737:chemistry*; D013500:Surface Tension; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D006838:Hydrocarbons; D010578:Petroleum; D012989:Soil Pollutants; D013501:Surface-Active Agents