Effect of pressure on the catalytic activity of subtilisin Carlsberg suspended in compressed gases

Enzymatic catalysis in cosolvent modified pressurized organic solvents

“…In this study, the apparent activation volume obtained directly from rate data in SCF ethane is −200 cm 3 /mol over the pressure range 104-173 bar. The sign of this activation volume observed is contrary to several previous investigations of lipase-catalyzed synthesis in SCFs (Fontes et al, 1998;Kamat et al, 1995b). Partial molar volumes, and therefore activation volumes, in SCFs are a function of molecular size and long-range interactions (Petsche and Debenedetti, 1991).…”

Applied Biotransformations in Green Solvents

“…Subtilisin has been used in the transesterification of N-acetyl-l-phenylalanine ethyl ester (APPE) and methanol in the presence of supercritical CHF 3 , [52] demonstrating that changes in the physical properties of the SCF can affect the catalytic efficiency of the enzyme. Fontes et al [113] proved that the same enzyme in scCO 2 worked with a rate of 97 % at 114 bar; however, the higher the pressure, the lower the enzymatic activity, up to 300 bar, at which pressure the enzyme is completely deactiviated.…”

Nuclear Magnetic Resonance of Laser-Polarized Noble Gases in Molecules, Materials, and Organisms

“…Furthermore, the density of supercritical xenon, and hence its physical properties (e.g., the volubility parameters and dielectric constant ), are strongly pressure dependent [118]; the physical properties of the solvent can therefore be manipulated to provide specific solvent environments [113]. The enhanced thermal stability of biomolecules in supercritical solvents may also prove advantageous for certain experiments [119,120].…”