文摘
Population based studies have shown a direct correlation between calcium and menaquinone-7 (MK-7) consumption and improved bone and cardiovascular health. MK-7 could only be produced by fermentation mainly using Bacillus subtilis species. However, this product is not readily available at an affordable price due to the high recovery and purification costs. Functional foods, therefore, due to the simpler production and less downstream processing steps can be seen as a low-cost and flexible alternative approach to address the current challenges in MK-7 production. In this study, we successfully developed a functional milk-product rich in MK-7 and calcium by using Bacillus subtilis natto. The maximum MK-7 concentration of 11.22 mg/L was achieved for the media consisted of standard milk and 1% (w/v) glycerol at 200 rpm, 1 vvm, 40 °C after 48 h of fermentation. Based on the results, MK-7 concentration increased between cell's mid-exponential growth and the stationary phase. The 80% of total MK-7 concentration was produced after 30 h of fermentation where the concentration of glycerol as a carbon source became exhausted. This research is the first report on its own which significantly contributes to the initial development of a novel functional dairy product high in MK-7. These results provide a basis of knowledge and new discoveries that can be carried out to develop a product that can act as a preventative in health issues such as osteoporosis and cardiovascular diseases.
