Fig. 6. (A) Resting cell assays of (+)-valencene hydroxylation to β-nootkanol and (+)-nootkatone using different constructs in S. cerevisiae CEN·PK2-1Ca. Promoters of HPO and AtCPR were noted at the bottom of the diagram. (B) Time responses of product accumulation. 24, 48, 72 and 96 represent the cultivation time in hours with PK2-25 harboring p181-V2H and p352-A1HC3. Mean values and standard deviations of biological triplicates are shown. The asterisk (***) indicates statistically significant differences in β-nootkanol formation (p < 0.001, student's t-test). The asterisk (**) indicates statistically significant differences in (+)-nootkatone formation (p < 0.05, student's t-test).