Supercritical fluids are superior media for catalysis by cross-linked enzyme microcrystals of subtilisin Carlsberg.
We report on the performance of cross-linked enzyme microcrystals (CLECs) of subtilisin Carlsberg in supercritical fluids (SC-fluids). The catalytic activity of CLECs in SC-ethane was found to be 2- to 10-fold greater than in hexane under the same conditions, using CLECs dried by propanol washing. Air-dried CLECs and lyophilized powders showed much lower activities, reflecting the same hydration hysteresis effects as in organic solvents. Reaction rates were much lower in SC-CO(2), especially at higher water activity, probably as a result of acid-base effects of carbonic acid on the enzyme.
Fontes
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Instituto de Tecnologia Quimica e Biológica, Universidade Nova de Lisboa, Apt. 127, 2781-901 Oeiras, Portugal.
Almeida
M C
MC
Garcia
S
S
Peres
C
C
Partridge
J
J
Halling
P J
PJ
Barreiros
S
S
D002384:Catalysis; D003460:Crystallization; D004951:Esterification; D007700:Kinetics; D013381:Subtilisins / Q000737:chemistry / Q000378:metabolism*
D013381:Subtilisins