title: Characterization of new glycolipid biosurfactants, tri-acylated mannosylerythritol lipids, produced by Pseudozyma yeasts.
abstract: Mannosylerythritol lipids (MELs) are glycolipid biosurfactants produced by Pseudozyma yeasts. They show not only the excellent interfacial properties but also versatile biochemical actions. In the course of MEL production from soybean oil by P. antarctica and P. rugulosa, some new extracellular glycolipids (more hydrophobic than the previously reported di-acylated MELs) were found in the culture medium. The most hydrophobic one was identified as 1-O-alka(e)noyl-4-O-[(4',6'-di-O-acetyl-2',3'-di-O-alka(e)noyl)-beta-D-mannopyranosyl]-D-erythritol, namely tri-acylated MEL. Others were tri-acylated MELs bearing only one acetyl group. The tri-acylated MEL could be prepared by the lipase-catalyzed esterification of a di-acylated MEL with oleic acid implying that the new glycolipids are synthesized from di-acylated MELs in the culture medium containing the residual fatty acids.
authors.affiliation: Research Institute for Innovation in Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, AIST Tsukuba Central 5-2, 1-1-1 Higashi, Tsukuba, Ibaraki, Japan.
authors.forename: Tokuma
authors.initials: T
authors.lastname: Fukuoka
authors.forename: Tomotake
authors.initials: T
authors.lastname: Morita
authors.forename: Masaaki
authors.initials: M
authors.lastname: Konishi
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Imura
authors.forename: Dai
authors.initials: D
authors.lastname: Kitamoto
mesh_terms: D002855:Chromatography, Thin Layer; D005227:Fatty Acids / Q000032:analysis; D006017:Glycolipids / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D013024:Soybean Oil / Q000032:analysis; D013501:Surface-Active Agents / Q000378:metabolism*; D014587:Ustilaginales / Q000378:metabolism*
chemical_list: D005227:Fatty Acids; D006017:Glycolipids; D013501:Surface-Active Agents; C439671:mannosylerythritol lipid; D013024:Soybean Oil