Figure 2

Cellular PHB contents under photoheterotrophy or heterotrophy in the dark with different initial levels of acetate (ACT) substrate.
Cells were cultured under normal photoautotrophy for 16 d to increase their biomass and then transferred to the normal nutrient (NORMAL), or that deficient in nitrogen (-N), phosphorus (-P) or nitrogen and phosphorus (-N-P). Data are shown as the mean ± 1 SD, derived from three to six independent experiments.