2.5. ABE fermentation with mixed glucose and xylose as substrates
ABE fermentation with mixed glucose (44.8 g/L) and xylose
(16.1 g/L) as substrates was carried out in 125 mL serum bottle
with a working volume of 50 mL. P2 medium was used as inorganic
mineral fermentation nutrients. The initial pH of the fermentation
broth was adjusted to 6.7 with calcium carbonate (5.0 g/L). The fermentation
bottle was flushed with nitrogen gas for 5 min and
crimp-sealed with rubber stopper. The bottles were loaded with
sugars and fermentation medium, autoclaved at 121 C for
15 min, inoculated with the actively growing seed-culture at 5%
(v/v). Fermentation was carried out at 36 C, 150 rpm, and under
strict anaerobic condition. Aliquots of samples were taken with
12-h interval.