Fig. 7
Improvement of LA production by neutralization and medium optimization. JHM86 was grown in a 125-mL flask containing 12.5-mL NMS medium (Control), NMS medium neutralized with 3.6-mM NaOH with or without additional nitrogen source (2× KNO3). 20% (v/v) methane was fed every 24 h. Cell growth (a) and LA production (b) were monitored during growth; c Methane consumption in the NMS medium with 3.6 mM NaOH and 2× KNO3 was determined by GC chromatography. Methane levels were measured before and after feeding 20% (v/v) methane every 24 h. Any remaining headspace gas was purged before feeding methane. Error bars indicate standard deviations of two independent experiments