Resolution of 2-bromo-arylacetic acid ester by Yarrowia lipolytica lipase in water/supercritical CO2 two-phase systems

• Published in: The Journal of supercritical fluids 2017-03, Vol.121, p.96-104
• Main Authors: Gérard, Doriane, Currie, Fiona, Medina Gonzalez, Yaocihuatl, Camy, Séverine, Marty, Alain, Condoret, Jean-Stéphane
• Format: Article
• Language: English
• Subjects: Biotechnology; Chemical and Process Engineering; Engineering Sciences; Enzymatic enantiomeric resolution; Life Sciences; Lipase; Supercritical carbon dioxide; Two-phase systems; Yarrowia lipolytica
• ISSN: 0896-8446; 1872-8162
• DOI: 10.1016/j.supflu.2016.11.012

[Display omitted] •Resolution of the 2-bromophenyl acetic octyl ester is performed in scCO2/water.•A mutant of Lip2 from Y. lipolityca enabled high enantioselectivity in scCO2/water.•The control of the pH is crucial in a system scCO2/water.•Low hydrophobicity of water saturated CO2 is probably not favourable to enzymatic activity. A mutated lipase from Yarrowia lipolytica was used in aqueous phase/scCO2 two-phase systems to perform the enzymatic resolution of (R, S) 2-bromophenyl acetic octyl ester. A solution of phosphate salt (1000mmol/L) was added to buffer the aqueous phase in contact with CO2 and resulting pH values around 6 were measured in a high pressure cell using a solvatochromic probe. Thus, an acceptable conversion rate and good enantioselectivity could be obtained but kinetics were shown to remain slower compared to an aqueous phase/decane two-phase system. Moreover, increasing pressure was shown to further slowdown the kinetics. This was hypothesized to be related to the mechanism of opening of the active site of the lipase which requires interfacial contact with a hydrophobic solvent phase. This condition is suspected not to be met in the case of scCO2 in contact with an aqueous phase because the amount of water dissolved in the supercritical phase diminishes its hydrophobicity.