Alpha-ketoglutaric acid (α-KG), as an essential intermediate in biosynthesis and drug synthesis, has a broad application prospect. However, the lower product concentration and impurities in the α-KG production make the downstream separation more complex and costly. In this study, α-KG was separated from biotransformation broth by salting-out extraction (SOE) combined with solar-driven distillation. First, the aqueous two-phase system (ATPS) consisting of acetone/(NH₄)₂SO₄ was selected by comparison. The effects of acetone/(NH₄)₂SO₄ concentration, temperature, α-KG concentration, and pH on the distribution behavior of α-KG in ATPS were investigated. Under the optimized conditions, higher extraction efficiency and purity of α-KG were obtained in the actual biotransformation broth. In addition, solar evaporation was used to achieve preconcentration of the organic phase and salt recovery, significantly reducing energy consumption. The method is environmentally friendly and easy to operate, providing a new idea for separating low concentration products in biosynthesis.

中文翻译：

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盐析萃取-太阳能蒸馏分离α-酮戊二酸

α-酮戊二酸（α-KG）作为生物合成和药物合成中必不可少的中间体，具有广阔的应用前景。然而，α-KG生产中较低的产品浓度和杂质使下游分离更加复杂和昂贵。在这项研究中，通过盐析萃取（SOE）结合太阳能驱动蒸馏从生物转化肉汤中分离出α-KG。首先，通过比较选择了由丙酮/(NH ₄ ) ₂ SO ₄组成的水相两相体系(ATPS) 。丙酮/(NH ₄ ) ₂ SO _4的影响研究了浓度、温度、α-KG浓度和pH对α-KG在ATPS中分布行为的影响。在优化的条件下，在实际的生物转化肉汤中获得了更高的α-KG提取效率和纯度。此外，利用太阳能蒸发实现有机相的预浓缩和盐回收，显着降低了能源消耗。该方法环保、操作简便，为生物合成中低浓度产物的分离提供了新思路。