Fig. 1
Fermentation of cellobiose by B. coagulans NL01. a Time course of cellobiose utilization under different initial concentrations. Green, 40 g/L; Pink, 60 g/L; Dark yellow, 80 g/L; Blue, 100 g/L; Magenta, 120 g/L. b Effect of cellobiose concentration on lactic acid production. The maximum concentration of lactic acid was obtained after 60, 72, 120, 240, and 240 h, respectively. Fermentations were carried out in 250-mL Erlenmeyer flasks containing 100-mL medium at 50 °C and 150 rpm on a rotary shaker. The medium contained the following (g/L): various amounts of cellobiose (40–120), yeast extract 2.5, corn syrup powder 1.2, MgSO4·7H2O 0.4, (NH4)2SO4 3, KH2PO4 0.22, MnSO4·H2O 0.03, FeSO4·H2O 0.03, and CaCO3 at 1/2 of the added sugar by weight. Values are the average of three independent experiments ± SD