Fig. 5.

Effects of different combinations of glucose and glycerol as substrate and heterologous addition of pyruvic acid and dodecane on the production of limonene. a Glucose of 2, 1.5, 1, 0.5, 0 % were respectively combined with glycerol of 0, 0.5, 1, 1.5, 2 % as substrate in the YP medium of strain Po1f-LN-051. b Pyruvic acid was added to the YPD medium of strain Po1f-LN-051 to a final concentration of 0, 2 , 4, or 8 g/L. c Dodecane was added to the YPD medium of strain Po1f-LN-051 with 4 g/L pyruvic acid as the auxiliary carbon source and the proportion of dodecane was from 2 to 10 %. Three repeats were performed for each medium, and error bars represent standard deviations. t tests were conducted to evaluate statistical significance at p < 0.05. Particularly, for (a) the asterisk shows statistical significance between 2 % glucose and other combinations of glucose and glycerol, for (b) the asterisk shows statistical significance between YPD medium containing 0 g/L pyruvic acid and other concentrations of pyruvic acid, and for (c) the asterisk shows statistical significance between YPD medium containing 2 % dodecane and other proportions of dodecane