Kynurenic acid (KYNA) is a compound derived from the tryptophan catabolic pathway. Antioxidant and neuroprotective properties have been confirmed for KYNA, which makes it an interesting and important metabolite of biomedical significance. In the present study, the yeast Yarrowia lipolytica was tested for KYNA biosynthesis. The results showed that Y. lipolytica strain S12 is able to produce KYNA in high concentrations (up to 21.38 μg/ml in culture broth and 494.16 μg/g cell dry weight in biomass) in optimized conditions in a medium supplemented with tryptophan. Different conditions of culture growth, including the source of carbon, its concentration and pH value of the medium, as well as the influence of an inhibitor or precursor of KYNA synthesis, were analysed. The obtained data confirmed the presence of KYNA metabolic pathway in the investigated yeast. To our best knowledge, this is the first study that reports KYNA production in the yeast Y. lipolytica in submerged fermentation.

中文翻译：

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一种利用解脂耶氏酵母生产犬尿酸的有效方法。

犬尿氨酸 (KYNA) 是一种源自色氨酸分解代谢途径的化合物。KYNA 的抗氧化和神经保护特性已得到证实，这使其成为具有生物医学意义的有趣且重要的代谢物。在本研究中，酵母解脂耶氏酵母进行了 KYNA 生物合成测试。结果表明，解脂耶氏酵母S12 菌株能够在优化条件下在补充有色氨酸的培养基中生产高浓度的 KYNA（培养液中高达 21.38 μg/ml，生物质中高达 494.16 μg/g 细胞干重）。分析了培养物生长的不同条件，包括碳源、培养基的浓度和 pH 值，以及抑制剂或 KYNA 合成前体的影响。获得的数据证实了所研究的酵母中存在 KYNA 代谢途径。据我们所知，这是第一项报告在深层发酵中酵母Y. lipolytica产生 KYNA 的研究。