Metabolic engineering of Bacillus subtilis for chiral pure meso-2,3-butanediol production

Table 2 Long-term fermentation of B. subtilis strains in the LB(Y) medium supplemented with 105 g/L glucose under microaerobic condition

Strain	CDW^a (g/L) (at 216 h)	2,3-BD^b (g/L)	AC^b (g/L)	Acetate^b (g/L)	Lactate^b (g/L)	Succinate^b (g/L)	Glucose consumed (g/h) (at 216 h)	Glucose uptake rate [g/(L h)]	2,3-BD productivity [g/(L h)]	2,3-BD yield (mol/mol)
BSF1	3.10 ± 0.38	40.84 ± 1.25(D)	3.47 ± 0.49	0.63 ± 0.11	1.19 ± 0.15	0.10 ± 0.02	87.3 ± 2.1	0.404	0.189	0.936
BSF9	3.82 ± 0.41	50.16 ± 0.52(M)	3.35 ± 0.79	0.62 ± 0.11	0.04 ± 0.00	0.16 ± 0.02	104.3 ± 0.5	0.483	0.232	0.962
BSF25	4.17 ± 0.22	49.59 ± 0.23(M)	2.66 ± 0.48	0.34 ± 0.04	1.17 ± 0.17	0.11 ± 0.02	105.0 ± 0.0	0.486	0.230	0.945

Bacteria were cultivated using a mixture of 100-mL LBR medium and 10.5 % glucose in a 250-mL flask kept agitated at a speed of 100 rpm and 37 °C; Data are average values and standard deviations of triplicate experiments. D, d-(−)-2,3-BD; M, meso-2,3-BD
^aThe CDW was calculated using the relationship: “CDW = OD₆₀₀*0.325”
^bThese metabolites were measured at 216 h

ISSN: 2731-3654