Department of Chemical Engineering, Faculty of Engineering, Kasetsart University, Chatuchak, Bangkok 10900, Thailand; Center of Excellence on Petrochemical and Materials Technology, Bangkok, Thailand.
Department of Chemical Engineering, Faculty of Engineering, Kasetsart University, Chatuchak, Bangkok 10900, Thailand.
J Biotechnol. 2019 May 20;297:1-8. doi: 10.1016/j.jbiotec.2019.02.012. Epub 2019 Mar 7.
Rhodococcus opacus PD630 was used to produce biomass and lipids in molasses-based media with and without osmotic stress. In a 7-day aerobic batch culture at 30 °C, the biomass and lipid concentrations were maximized using an initial molasses concentration of 80 g/L and ammonium acetate (nitrogen source) concentration of 2.14 g/L. At a fixed initial molasses concentration of 80 g/L, the concentration of the nitrogen source was further fine-tuned to 2.25 g/L, to maximize the lipid content of the biomass to around 30% by dry mass. This medium was used to test the effects of stressing salts (sodium acetate, magnesium sulfate, sodium chloride) on production of lipids and biomass. A two-step bolus feeding with magnesium sulfate and sodium acetate, enhanced the final biomass concentration to around 19 g/L (a 50% increase relative to control), but the lipid content in the biomass was reduced to around 16% w/w. A 33% enhancement in lipid concentration relative to control, was achieved by feeding magnesium sulfate and sodium acetate. Sugarcane molasses could be effectively used to produce biomass and lipids instead of using the much more expensive pure carbon sources such as glucose and sucrose.
费氏中华根瘤菌 PD630 被用于在有渗透压胁迫和无渗透压胁迫的糖蜜基培养基中生产生物量和脂类。在 30°C 的 7 天好氧分批培养中，初始糖蜜浓度为 80g/L，乙酸铵（氮源）浓度为 2.14g/L 时，生物量和脂类浓度达到最大值。在固定初始糖蜜浓度为 80g/L 的情况下，进一步将氮源浓度精细调整为 2.25g/L，使生物量的脂类含量最大化至约 30%（按干重计）。该培养基用于测试盐（乙酸钠、硫酸镁、氯化钠）胁迫对脂类和生物量生产的影响。两步补料法添加硫酸镁和乙酸钠，将最终生物量浓度提高到约 19g/L（相对于对照提高了 50%），但生物量中的脂类含量降低至约 16%（w/w）。通过添加硫酸镁和乙酸钠，与对照相比，脂类浓度提高了 33%。与使用葡萄糖和蔗糖等昂贵的纯碳源相比，可有效地使用甘蔗糖蜜来生产生物量和脂类。
