The growth of saccharomyces cerevisiae and the kinetics of biotransformation of chiral 2,6,6-trimethylcyclohex-2-ene-1,4-dione into its corresponding chiral precursor
Kajian ini dijalankan bagi mengkaji kadar pertumbuhan sel Saccharomyces cerevisiae selama 3 hari dalam mendapatkan kadar pertumbuhan maksimum sel. Selain itu, tujuan kajian ini dijalankan ialah untuk mengkaji keupayaan keseluruhan sel Saccharomyces cerevisiae dalam mentransformasikan ketoisoforon kepada pelopor kiral yang bersesuaian. Kajian kinetic terhadap proses biotransformasi menggunakan sel rehat juga telah dijalankan. Berat yis yang diperolehi selepas dikeringkn untuk 1 Liter balang ialah 19.567 g / L. Fasa pertumbuhan yis mengikut trend yang biasa terdiri daripada fasa lag, fasa eksponen, fasa pegun dan fasa kematian. Biotransformasi ketone pada kepekatan awal 1,3,5 dan 8 g / L ditentukan dengan menggunakan kromatografi gas dan GC-MS untuk mencari produk atau pemangkin pertengahan. Untuk semua kepekatan awal, pembentukan 2,2,6 - trimethyl-1 ,4-cyclohexadione ditemui. Dari persamaan Michaelis-Menten, kinetik berterusan Vmax dan Km ditentukan dari eksperimen kelalang ialah 0.56513 g / hr.gcell dan 38.358 g / L. Carbonyl enzime tidak dapat menukarkan substrat kepada produk mahupun pemangkin sedangkan untuk semua konsentrasi awal, enoate enzime atau dikenal OYE didapati telah menghasilkan pemangkin iaitu 2,6,6-Trimethyl-1,4-cyclohexanedione.
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In this study, the Saccharomyces cerevisiae or known as Baker yeast growth phase and its max growth rate are determine. The present study described the biotransformation of ketoisophorone using Saccharomyces cerevisiae into its corresponding chiral precursor. The biotransformation using resting cell had been done. The highest cell concentration obtained for 1 Liter of medium is at 19.567 g/L. The growth phase of yeast followed the common trend which consist of lag phase, exponential phase, stationary phase and death phase. The biotransformation of ketone at initial concentration 1, 3, 5 and 8 g/L were determined by using gas chromatography and GC-MS to find its product or intermediate formation. For all concentration, the formation of intermediate 2,2,6- trimethyl-1,4-cyclohexadione was discovered. From the Michaelis-Menten equation, the kinetics constant of Vmax and Km were determined from the shake flask experiment to be 0.56513 g/hr.gcell and 38.358 g/L respectively. In this studies, the present of intermediate was discovered and its reaction was reduced using enoate reductase enzyme. While for carbonyl reductase no reaction occurred in order to do biotransformation.
The growth of saccharomyces cerevisiae and the kinetics of biotransformation of chiral 2,6,6-trimethylcyclohex-2-ene-1,4-dione into its corresponding chiral precursor