Effect of dodecane overlay volume on retinoid production. Effect of the dodecane overlay volume on retinoid production and cell growth of E. coli (pT-DHBSR/pS-NA) in the two-phase culture. The culture was carried out in 2YT medium containing 2% (w/v) glycerol and 0.2% (w/v) arabinose at 29°C, and different dodecane volumes from 1 mL to 5 mL were overlaid on the 5 mL culture broth. For the 6 mL dodecane overlay, the dodecane overlay was divided into three aliquots of 2 mL added at 0, 24 and 48 hours. For retinoid production, retinal, retinol, and retinyl acetate are indicated with light gray, dark gray, and black, respectively. For cell growth, the overlaid dodecane volumes are indicated as symbols; 0 mL, closed squares; 1 mL, closed circles; 2 mL, closed triangles; 3 mL, closed reversed triangles; 4 mL, closed diamonds; 5 mL, open squares; 6 mL, open circles (A). Proportions of retinoids produced as a function of culture time and dodecane overlay volume are represented as percentages of the total retinoids. Retinal, retinol, and retinyl acetate are indicated in light gray, dark gray, and black, respectively (B).