The effectiveness of micro-aeration on lactate (LA) production by metabolically engineered Escherichia coli was evaluated in 1 L bioreactors containing mineral media and glucose (70 g/L). Volumetric oxygen transfer coefficients (k_La) between 12.6 and 28.7 h⁻¹ increased the specific growth rate (µ) and volumetric productivity (Q_LA) by 300 and 400%, respectively, without a significant decrease in lactate yield (Y_LA), when compared with non-aerated fermentations. A k_La of 12.6 h⁻¹ was successfully used as a criterion to scale-up the production of l and d-lactate from 1 to 11 and 130 L. Approximately constant Q_LA and Y_LA values were obtained throughout the fermentation scale-up process. Furthermore, a d-lactogenic fermentation was carried out in 1 L bioreactors using avocado seed hydrolysate as a culture medium under the same k_La value, displaying high Q_LA and Y_LA.

在含有矿物培养基和葡萄糖 (70 g/L) 的 1 L 生物反应器中评估了微曝气对代谢工程大肠杆菌生产乳酸 (LA) 的有效性。12.6 和 28.7 h ^-1之间的体积氧转移系数 (k _L a)使比生长率 ( µ ) 和体积生产率 (Q _LA ) 分别增加了 300% 和 400%，而乳酸产量 (Y _LA )没有显着降低，与非充气发酵相比。12.6 h ^{-1 的}k _L a被成功用作扩大l和d生产的标准-乳酸从 1 到 11 和 130 L。在整个发酵放大过程中获得了近似恒定的 Q _LA和 Y _LA值。此外，在相同的 k _L a 值下，使用鳄梨种子水解物作为培养基在 1 L 生物反应器中进行了d-产乳发酵，显示出高 Q _LA和 Y _LA。