Fig. 5. De novo production of (+)-valencene and β-nootkatol using PK2-24 in 50 mL bi-phasic conical flask cultures. One μL aliquots of n-dodecane phase for each sample were analyzed by GC-FID. (A) Carbon source in induction medium effects on the products accumulation. Yeasts were cultured in 20 g L−1 glucose at 30 °C for 14–16 h for cell growth. Cells were collected by centrifugation and transferred into fresh induction medium containing galactose to induce HPO and AtCPR expression, SG (2% galactose), SGG (2% galactose and 10% glycerol) and SGR (2% galactose and 0.7 raffinose), respectively. (B) Time and temperature responses of product accumulation. 24, 48, 72 and 96 represent the cultivation time in hours. Mean values and standard deviations of biological triplicates are shown. The asterisk (***) indicates statistically significant differences in (+)-valencene formation (p < 0.001, student's t-test).
