The physicochemical properties and chemical composition of trehalose lipids produced by Rhodococcus erythropolis 51T7.
This study analyzed the chemical and physical properties of a biosurfactant synthesized by Rhodococcus sp. 51T7. The biosurfactant was a trehalose tetraester (THL) consisting of six components: one major and five minor. The hydrophobic moieties ranged in size from 9 to 11 carbons. The critical micelle concentration (CMC) was 0.037g L(-1) and the interfacial tension against hexadecane was 5mN m(-1). At pH 7.4 the glycolipid CMC/critical aggregation concentration (CAC) was 0.05g L(-1) and at pH 4 it was 0.034g L(-1). A phase diagram revealed effective emulsification with water and paraffin or isopropyl myristate. A composition of 11.3-7.5-81.8 (isopropyl myristate-THL-W) was stable for at least 3 months. The HLB was 11 and the phase behaviour of the glycolipid revealed the formation of lamellar and hexagonal liquid-crystalline textures.
Lab. of Microbiology, Faculty of Pharmacy, University of Barcelona, Barcelona, Spain. ammarques@ub.edu
A M
AM
Marqués
A
A
Pinazo
M
M
Farfan
F J
FJ
Aranda
J A
JA
Teruel
A
A
Ortiz
A
A
Manresa
M J
MJ
Espuny
D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects*; D004655:Emulsions / Q000737:chemistry; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D005798:Genes, Bacterial; D020459:Genes, rRNA; D006017:Glycolipids / Q000032:analysis* / Q000302:isolation & purification / Q000633:toxicity*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects; D051379:Mice; D008823:Micelles; D009994:Osmolar Concentration; D044367:Phase Transition; D012240:Rhodococcus / Q000737:chemistry* / Q000235:genetics; D014199:Trehalose / Q000032:analysis* / Q000302:isolation & purification / Q000633:toxicity*
D004655:Emulsions; D006017:Glycolipids; D008823:Micelles; D014199:Trehalose