Rasemik-2-pentanolün lipaz katalizli kinetik rezolüsyonu
No Thumbnail Available
Files
Date
2015
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Fen Bilimleri Enstitüsü
Abstract
In this study, the effects of enzyme, acyl donor, substrate concentration and acyl donor/racemic-2-pentanol mol ratio on the kinetic resolution of racemic-2-pentanol, of which have been used as a key chiral intermediate required in the synthesis of several potential anti-Alzhemeir drugs, with transesterification were investigated, and substrate and enzyme concentration was optimized with Response Surface Methadology (RSM). Internal and external mass transfer limitations were studied at batch mode and reaction kinetic model was obtained. Then continuous flow production parameters and packed bed bioreactor models were built and solved. First, production parameters were investigated with different type of enzyme and acyl donor. The optimum transesterification conditions were obtained with Novozyme 435 and vinil butyrate with the 50% conversion, 99% of enantiomeric excess for the substrate at 30 minutes. These condtions were used on the RSM and the optiumum conditions were obtained with 1500 mM substrate and 4 mg/ml enzyme concentration with 24.88 mM/min maximum initial reaction rate. Maximum initial reaction rate was verified expermentally, and obtained at 28.48 mM/min. The close rate values showed that the equation was suitable for the reaction. Due to the use of immobilized enzyme, external and internal mass transfer limitations were studied, and it is concluded that above 150 rpm external mass transfer limitation could be negligible and there were no internal mass transfer limitation due to the ineffectiveness of the enzyme particular size on initial reaction rate. It was obtained that Ping Pong bi bi mechanism without inhibition was the appropriate reaction kinetic for this process according to the studies with batch mode. Kinetic parameters were determined with Polymath 6.1 software and maximum reaction rates, Km for R-2-pentanol and Km for vinyl butyrate were found 4.16 mmol/min/g enzyme, 103.73 mM and 51.18 mM, respectively. Continuous flow mode studies were held with two different packed bed bioreactor, which had L/D=10 and L/D=12.5. Investigations were carried out with diffent flow rates and substrate concentrations and process model was solved with MATLAB.
Description
Keywords
Rasemik-2-pentanolün, rezolüsyonu