Figure 4.

(a) For the Ca²⁺ concentration in culture media, there was no obvious change among the three groups in the first seven days; (b) for the intracellular calcium quantification, there was no significant difference between the static-state culture and spinner-flask bioreactor at week one and two. However, the static-state culture had significantly higher Ca²⁺ contents relative to the spinner flask at week three and four. The spinner flask also had significantly higher Ca²⁺ contents when compared to those of the flow reactor during the four-week experimental period.