Figure 10 Changes of intracellular NAD+/NADH ratio in shake flask fed-batch LP and HP CHO cells under both constant temperature and temperature downshift cultures. (●, black) temperature downshift culture, (■, red) constant temperature culture. (a) Time-series NAD+/NADH ratio in LP CHO cell; (b) Significance analysis of NAD+/NADH ratio in LP CHO cells on days 8-11; (c) Time-series NAD+/NADH ratio in HP CHO cells; (d) Significance analysis of NAD+/NADH ratio in HP CHO cells on days 8-11. Experimental values represent three biological replicates ± SD. Two-tailed Student’s t-test was conducted using GraphPad Prism 8.0 ((*) p < 0.05, (**) p < 0.01, (***) p < 0.001 and (****) p < 0.0001).