Pengurangan ketoisoforon oleh seluruh sel, jenis yeast Baker jenis II telah diteliti baru-baru ini. Salah satu produk utama pengurangan biotransformasi ialah 2,6,6-trimetilkiklohex-2-ene-1,4-dione (ketoisoforon) adalah (4R, 6R) -4-hydroxy-2,6,6-trimethylcyclohexanone atau juga dinamakan sebagai (4R, 6R) -aktinol menggunakan ‘Saccharomyces cerevisiae’ pada masa kini dengan glukosa sebagai sumber karbon. Biotransformasi ketoisoforon (KIP) membentuk levodione juga dinamakan sebagai 6R-dihydro-oxoisoforone (DOIP), yang merupakan perantaraan sebelum pengurangan selanjutnya menjadi aktinol (ACT). Eksperimen ini hanya tertumpu pada fasa kematian penapaian S. cerevisiae di mana substrat, ketoisoforon (KIP) diperkenalkan dan tempoh masa 22h fasa kematian yang bermula dari jam 38 hingga 60 penapaian sel yis. Ketersediaan dan kestabilan kofaktor nicotinamide adenine dinucleotide (NADH) atau nicotinamide adenine dinucleotide fosfat dengan kehadiran glukosa melalui proses kitaran Kreb adalah penting dalam biotransformasi ketoisophorone semasa fasa tersebut ditentukan oleh bacaan penyerapan menggunakan spektrofotometer UV-Vis. Kerja-kerja ini juga menyiasat jumlah substrat dan perantaraan semasa 22 jam tindak balas untuk menentukan aktiviti kedua-dua jenis enzim dalam sel-sel yis yang bertanggungjawab untuk biotransformasi ini iaitu karbonyl reduktase (CBR) dan enoate reduktase (ER) untuk menghasilkan kiral alkohol (4R, 6R) -aktinol. Hasil dari eksperimen menunjukkan bahawa dalam fasa kematian menghasilkan intermediate dan juga produk dalam tindakbalas biotransformasi .
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The reduction of ketoisophorone by the whole cell, Baker’s yeast cell type II has been researched recently. One of the major product of the biotransformation reduction of 2,6,6-trimethylcyclohex-2-ene-1,4-dione (ketoisophorone) is (4R,6R)-4-hydroxy-2,6,6-trimethylcyclohexanone or also named as (4R,6R)-actinol using Saccharomyces cerevisiae in the present of glucose as the carbon source. The biotransformation of ketoisophorone (KIP) forms levodione also named as 6R-dihydro-oxoisophorone (DOIP), which is intermediate before further reduction into actinol (ACT). This experiment only focussed on the death phase of S. cerevisiae fermentation where the substrate, ketoisophorone(KIP) was introduced and the time duration of 22h of death phase which is started from 38th hour until 60th of fermentation of yeast cells. The availability and stability of cofactor, nicotinamide adenine dinucleotide (NADH) or nicotinamide adenine dinucleotide phosphate (NADPH) by the presence of glucose through Kreb’s cycle process was essential in the biotransformation of ketoisophorone during that phase was determined by the reading of absorbance using UV-Vis spectrophotometer. This work was also investigate the amount of substrate and intermediate present during 22 h of reaction in order to determine the activity of the two types of ezymes within the yeast cells which is responsible for this biotransformation which is carbonyl reductase (CBR) and enoate reductase (ER) to produce a chiral alcohol of (4R,6R)-actinol. The result showed that the death phase produced the intermediate as well as product which is actinol with the aid of cofactor availability during the reaction of biotransformation.
On 2,6,6-trimethylcyclohex-2-ene-1,4-dione biotransformation beyond the stationary phase of baker’s yeast type III / Mohd Ridzwan Remlee