508968.fig.003a
(a)
508968.fig.003b
(b)
508968.fig.003c
(c)
508968.fig.003d
(d)
Figure 3: Response surface showing the interaction between five parameters and biomass (mg/mL); (a) sucrose and NaNO3, (b) sucrose and Triton X-100, (c) yeast extract and Zn+2, (d) NaNO3 and Triton X-100. Other variables are constant at their center points. The numbers inside the contour plots indicate conversion yield (mg/mL) of the biomass.