title: Characterization of rhamnolipids produced by a Pseudomonas aeruginosa mutant strain grown on waste oils.
abstract: Pseudomonas aeruginosa EBN-8 mutant rhamnolipids produced on waste oils were investigated using normal-phase thin layer chromatography and fast atom bombardment mass spectrometry. Negative ion mode mass spectra yielded [M - H](-) ions and their fragment ions, which gave some indications on the sequence of rhamnolipid biosynthesis. Five rhamnolipid homologs [viz. RC(10)C(10) (m/z 503), RC(12)C(10) or RC(10)C(12) (531), RRC(10)C(8) or RRC(8)C(10) (621), RRC(10)C(10) (649) and RRC(12)C(10) or RRC(10)C(12) (677)] were detected in four rhamnolipid combinations under the different carbon sources. The prevalence of rhamnolipids was confirmed by Fourier transform infrared and one-dimensional proton nuclear magnetic resonance. We also observed some correlations between the tensioactive characteristics and structural chemistry of the rhamnolipid surfactants.
authors.affiliation: National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan. zarazapk@yahoo.com
authors.forename: Zulfiqar A
authors.initials: ZA
authors.lastname: Raza
authors.forename: Zafar M
authors.initials: ZM
authors.lastname: Khalid
authors.forename: Ibrahim M
authors.initials: IM
authors.lastname: Banat
mesh_terms: D002855:Chromatography, Thin Layer; D005229:Fatty Acids, Monounsaturated; D006017:Glycolipids / Q000096:biosynthesis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D000074262:Rapeseed Oil; D013024:Soybean Oil; D013501:Surface-Active Agents / Q000737:chemistry*; D014866:Waste Products
chemical_list: D005229:Fatty Acids, Monounsaturated; D006017:Glycolipids; D000074262:Rapeseed Oil; D013501:Surface-Active Agents; D014866:Waste Products; C418382:rhamnolipid; D013024:Soybean Oil