Abstract The unconventional yeast Yarrowia lipolytica is known for its capability to synthesize different metabolites of industrial interest such as citric acid (CA). The numerous applications of CA trigger continuous research on improved production systems and substrates costs reduction. In this context, the present contribution explored the production of CA using chosen strains of Y. lipolytica in fermentation media formulated with low-cost and non-seasonal nutrient sources derived from the corn wet milling process, such as food grade corn syrups and corn steep liquor (CSL). Besides nutrient sources assay, the effect of carbon source concentration and C/N ratio was evaluated. In media formulated with high fructose syrup and CSL proper manipulation of the mentioned variables allowed attaining CA productions of up to 38 g/L in flasks culture. Moreover, the bioreactor scale-up allowed a 130%-increase in productivity and drastic fermentation time reduction. Overall, the combination of these low-cost nutrient sources of predictable composition derived from the corn processing industry that may be stored at room temperature seems attractive for CA production. The simplicity of the fermentation medium further makes it promising for higher-than-laboratory scale production of CA.

中文翻译：

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探索使用玉米湿磨产品作为替代低成本发酵培养基用解脂耶氏酵母生产柠檬酸

摘要 非常规酵母解脂耶氏酵母以其合成具有工业价值的不同代谢物（如柠檬酸 (CA)）的能力而闻名。CA 的众多应用引发了对改进生产系统和降低基材成本的持续研究。在这种情况下，本论文探讨了在发酵培养基中使用选定的解脂耶氏酵母菌株生产 CA，发酵培养基由来自玉米湿磨过程的低成本和非季节性营养源配制而成，例如食品级玉米糖浆和玉米浸膏。酒（CSL）。除了营养源测定外，还评估了碳源浓度和 C/N 比的影响。在用高果糖浆和 CSL 配制的培养基中，对上述变量的适当操作允许在烧瓶培养中获得高达 38 g/L 的 CA 产量。此外，生物反应器的放大使生产力提高了 130%，发酵时间大大减少。总体而言，这些源自玉米加工业且可在室温下储存的可预测成分的低成本营养源的组合似乎对 CA 生产具有吸引力。发酵培养基的简单性进一步使其有望用于高于实验室规模的 CA 生产。