Abstract Carboxylic acids (CA) are high added-value compounds that can be produced via anaerobic fermentation by using agroindustrial residues as substrates. However, different compounds in wastewater impose uncontrolled metabolic pathways, in which the acidogenic fermentation kinetics need to be elucidated. This work aimed to assess the potential production of CA from dairy wastewater (DW) and to perform the kinetic modeling of the process. The experiments were conducted in quadruplicate batch reactors (250 mL of working volume) with inoculum from a brewery UASB at 0.61 ± 0.04 gCOD gVSS−1. To inhibit methanogenesis, 0.05 % (v/v) chloroform was added to the reactors. The tests showed that DW is a readily fermentable substrate to acidogenic microorganisms because it presents high rates of short-chain CA formation in the first two days of the experiment. The low concentrations of medium-chain CA found indicate that fats and proteins did not function as the main carbon source for DW fermentation. The yield obtained was 0.66 mgCA mgCODA−1, which corresponds to 0.83 mgCODCA mgCODA−1. Kinetic modeling studies have shown that mathematical models that can describe an exponential phase, such as First-order and Fitzhugh models, are suitable for simulating the production of carboxylic acids. Finally, DW seems to be a promising substrate to be investigated in the carboxylic platform.

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以乳制品废水为底物生产羧酸的潜力评估和动力学模型

摘要 羧酸（CA）是一种高附加值的化合物，可以利用农业工业残留物作为底物，通过厌氧发酵生产。然而，废水中的不同化合物强加了不受控制的代谢途径，其中需要阐明产酸发酵动力学。这项工作旨在评估乳制品废水 (DW) 中 CA 的潜在产量，并对该过程进行动力学建模。实验在一式四份的间歇式反应器（250 mL 工作体积）中进行，接种物来自啤酒厂 UASB，浓​​度为 0.61 ± 0.04 gCOD gVSS-1。为了抑制产甲烷，将 0.05% (v/v) 氯仿添加到反应器中。测试表明，DW 是产酸微生物的一种易于发酵的底物，因为它在实验的前两天表现出很高的短链 CA 形成率。发现的低浓度中链 CA 表明脂肪和蛋白质不是 DW 发酵的主要碳源。获得的产量为 0.66 mgCA mgCODA-1，相当于 0.83 mgCODCA mgCODA-1。动力学建模研究表明，可以描述指数相的数学模型（例如一阶模型和 Fitzhugh 模型）适用于模拟羧酸的生产。最后，DW 似乎是在羧酸平台中研究的有前途的底物。发现的低浓度中链 CA 表明脂肪和蛋白质不是 DW 发酵的主要碳源。获得的产量为 0.66 mgCA mgCODA-1，相当于 0.83 mgCODCA mgCODA-1。动力学建模研究表明，可以描述指数相的数学模型（例如一阶模型和 Fitzhugh 模型）适用于模拟羧酸的生产。最后，DW 似乎是在羧基平台中研究的有前途的底物。发现的低浓度中链 CA 表明脂肪和蛋白质不是 DW 发酵的主要碳源。获得的产量为 0.66 mgCA mgCODA-1，相当于 0.83 mgCODCA mgCODA-1。动力学建模研究表明，可以描述指数相的数学模型，例如一阶模型和 Fitzhugh 模型，适用于模拟羧酸的生产。最后，DW 似乎是在羧基平台中研究的有前途的底物。