TY - JOUR
T1 - Kinetics and modeling of (R,S)-1-phenylethanol acylation over lipase
AU - Kirilin, Alexey
AU - Sahin, Serap
AU - Mäki-Arvela, Päivi
AU - Wärnå, Johan
AU - Salmi, Tapio
AU - Murzin, Dmitry Yu
N1 - Copyright:
Copyright 2010 Elsevier B.V., All rights reserved.
PY - 2010/10
Y1 - 2010/10
N2 - The kinetics of the acylation of (R,S)-1-phenylethanol was investigated using lipase as a catalyst. The main parameters were temperature, reaction atmosphere, different acyl donors, and different amounts of acyl donor as well as the presence of some additives in the reaction mixture. The initial reaction rate increased with increasing temperature and with a decreasing amount of an acyl donor. The activated esters, such as isopropenyl- and vinyl acetate, exhibited very high acylation rates for R-1-phenylethanol, whereas low rates were obtained with ethyl acetate and 2-methoxyethyl acetate. The addition of water and acetophenone decreased the acylation rate. A kinetic model was developed based on a sequential step mechanism, in which enzyme was reacting in the first step with an acyl donor followed by the reaction of a modified enzyme complex with the reactant, R-1-phenylethanol.Comparisonwith experimental data obtained at different temperatures allowed simplification of this model, leading to a kinetic equation with just one apparent parameter. The influence of the amount of acyl donor, ethyl acetate, could be quantitatively described by taking into account the competitive inhibition of the ethanol produced. The rate constants and apparent activation energy for experiments performed under different temperatures and the amounts of acylation agent were determined. The apparent activation energy was 24.5 kJ/mol.
AB - The kinetics of the acylation of (R,S)-1-phenylethanol was investigated using lipase as a catalyst. The main parameters were temperature, reaction atmosphere, different acyl donors, and different amounts of acyl donor as well as the presence of some additives in the reaction mixture. The initial reaction rate increased with increasing temperature and with a decreasing amount of an acyl donor. The activated esters, such as isopropenyl- and vinyl acetate, exhibited very high acylation rates for R-1-phenylethanol, whereas low rates were obtained with ethyl acetate and 2-methoxyethyl acetate. The addition of water and acetophenone decreased the acylation rate. A kinetic model was developed based on a sequential step mechanism, in which enzyme was reacting in the first step with an acyl donor followed by the reaction of a modified enzyme complex with the reactant, R-1-phenylethanol.Comparisonwith experimental data obtained at different temperatures allowed simplification of this model, leading to a kinetic equation with just one apparent parameter. The influence of the amount of acyl donor, ethyl acetate, could be quantitatively described by taking into account the competitive inhibition of the ethanol produced. The rate constants and apparent activation energy for experiments performed under different temperatures and the amounts of acylation agent were determined. The apparent activation energy was 24.5 kJ/mol.
UR - http://www.scopus.com/inward/record.url?scp=77957587762&partnerID=8YFLogxK
U2 - 10.1002/kin.20504
DO - 10.1002/kin.20504
M3 - Article
AN - SCOPUS:77957587762
SN - 0538-8066
VL - 42
SP - 629
EP - 639
JO - International Journal of Chemical Kinetics
JF - International Journal of Chemical Kinetics
IS - 10
ER -