Pyocyanin pigment assisting biosurfactant-mediated hydrocarbon emulsification

• Published in: International biodeterioration & biodegradation 2013-11, Vol.85, p.278-283
• Main Authors: Das, Palashpriya, Ma, Luyan Z.
• Format: Article
• Language: English
• Subjects: ammonium salts; Biosurfactant; biosurfactants; dry environmental conditions; Emulsification; emulsifying; glucose; Heavy metal; Hydrocarbons; industry; mixing; Paints; peptones; Pigments; Protective coatings; Pseudomonas; pyocyanin; Pyocyanin pigment; Remediation; Strain; synergism; yields
• ISSN: 0964-8305; 1879-0208
• DOI: 10.1016/j.ibiod.2013.07.013

A plethora of Pseudomonas strains was checked for their biosurfactant and pigment-producing abilities in Bushnell-Haas (BH) medium and proteose peptone glucose ammonium salts (PPGAS) medium. Five strains from different origins produced only biosurfactant in BH medium but both biosurfactant and pyocyanin pigment in PPGAS medium. Biosurfactant and pyocyanin exhibited a peculiar correlation as the culture supernatants containing both components emulsified hydrocarbons more than the biosurfactant alone. Enhancement in emulsification also occurred by mixing pyocyanin from PPGAS medium and biosurfactant from BH medium. Prior reports indicated that pigments protect producer strains from certain environmental stresses. The interesting finding of this study of pyocyanin pigment enhancing biosurfactant-mediated hydrocarbon emulsification was independent of the source of biosurfactant isolation. The synergistic action of pigment and biosurfactant found may be a general phenomenon for other Pseudomonas strains producing both biosurfactant and pigment, thus helping them to survive in arid conditions. The pigment-aided emulsification may help in lowering the requirement of biosurfactive agents for remediation purposes, which will also be helpful economically as the biosurfactants have very low yields. The enhancement in emulsification by the coupling of pigment with biosurfactant can have a significant impact in the paint industry and sectors dealing in environmental remediation. •Bacterial strains produce only biosurfactant in BH medium while pyocyanin along with biosurfactant in PPGAS medium.•Hydrocarbon emulsification by biosurfactants is enhanced in presence of pyocyanin.•Phenomenon is observed irrespective of source of biosurfactant isolation.•Pyocyanin endowed producer strains with the property of heavy metal tolerance helping bacterial survival in arid conditions.•Observed result of pigment-mediated enhancement in emulsification by biosurfactant can have potential commercial importance.