Dalam kajian ini, biotransformasi (+) - valencene kepada (+) - nootkatone melalui Yarrowia lipolytica telah dikaji. Terdapat beberapa produk perantaraan yang terbentuk sebelum (+) - nootkatone boleh dihasilkan dari biotransformasi. Proses ini berlaku di bawah fasa pertumbuhan pegun. Kemudian, lengkung pertumbuhan untuk (+)-valencene dikaji terlebih dahulu untuk mendapatkan tempoh fasa pegun. Ini kerana pertumbuhan maksimum yang akan berlaku dalam fasa pegun dan dapat membantu dalam kajian ini. Sebaik sahaja maklumat biotransformasi telah dilakukan, produk telah diambil untuk analisis kromatografi gas untuk menilai secara kuantitatif kesan substrat (+) - valencene dan produk (+) - nootkatone semasa kemajuan biotransformasi. Sesetengah data grafik yang ditunjukkan dalam kajian ini menunjukkan bahawa kepekatan (+) - valensena berkurangan sementara kepekatan (+) - nootkatone meningkat mengikut masa. Terdapat 4 kepekatan yang berbeza (+) - valencene yang digunakan iaitu 0.002, 0.004, 0.006 dan 0.010 g / L. Keempat kepekatan yang berbeza ini menunjukkan hasil yang berbeza. Hasilnya menunjukkan bahawa (+) - nootkatone dikesan semasa analisis kromatografi gas dan mempunyai potensi untuk pengeluaran (+) - nootkatone masa depan. Hasilnya menunjukkan bahawa hanya pada kepekatan substrat 0.010 g / L mampu menghasilkan (+) - nootkatone dengan sekitar 150μg /L.
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In this study, a biotransformation of (+)-valencene to (+)-nootkatone through Yarrowia lipolytica was investigated. There were some intermediate products formed before (+)-nootkatone can be produced from the biotransformation. The process take place under stationary phase of growth. Then, growth curve for (+)-valencene were being studied first in order to obtain the stationary phase duration. This is because the maximum possible growth occur in stationary phase hence able to assist in this study. Once the biotranformation has been done, the product was taken to gas chromatography analysis to evaluate quantitatively the effect of substrate (+)-valencene and product (+)-nootkatone during the progress of biotransformation. Some graphical data represented in this study show that various concentration of (+)-valencene depleted while concentration of (+)-nootkatone increase respected to time. There are 4 different concentration of (+)-valencene used which are 0.002, 0.004, 0.006 and 0.010 g/L. These four different concentration show different result. The result revealed that (+)-nootkatone was detected during the gas chromatographic analysis has the potential for future (+)-nootkatone production. The result show that only at 0.010 g/L substrate concentration able to produce (+)-nootkatone with around 150μg/L.