A nutritional food rich in
menaquinone-7 has a potential in preventing
osteoporosis and
cardiovascular diseases. The static fermentation of Bacillus subtilis natto is widely regarded as an optimum process for
menaquinone-7 production. The major issues for the bulk production of
menaquinone-7 are the low fermentation yield, biofilm formation and the use of organic
solvents for the
vitamin extraction. In this study, we demonstrate that the dynamic fermentation involving high stirring and aeration rates enhances the yield of fermentation process significantly compared to static system. The
menaquinone-7 concentration of 226 mg/L was produced at 1,000 rpm, 5 vvm, 40 °C after 5 days of fermentation. This concentration is 70-fold higher than commercially available food products such as natto. Additionally, it was found that more than 80% of
menaquinone-7 was recovered in situ in the
vegetable oil that was gradually added to the system as an anti-foaming agent. The intensification process developed in this study has a capacity to produce an oil rich in
menaquinone-7 in one step and eliminate the use of organic
solvents for recovery of this compound. This oil can, therefore, be used for the preparation of broad range of supplementary and dietary food products rich in
menaquinone-7 to reduce the risk of
osteoporotic fractures and
cardiovascular diseases.