Fig. 6

Effect of carbon source and aeration/respiration on vitamin K2 production in L. lactis MG1363. a Fold changes in specific concentrations with respect to glucose, static fermentation. b Fold changes in titres with respect to glucose, static fermentation. c Relative abundance of MKs. Strain MG1363 was cultivated in M17 with indicated carbon source at 30 °C for 48 h. For static fermentation, full tubes of cultures were statically incubated. For aerated fermentation, bacterial cultures were incubated in flasks with head space, shaken at 120 rpm. For respiration, bacterial cultures were incubated in flasks with head space, shaken at 120 rpm and with 2 µg/ml heme added. Values shown are from averages ± SEMs of biological triplicates. Dunnett test (2-sided) was performed within each carbon source group, and the control groups were in all cases static fermentation (*P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001)