Sawada Kazunori, Koyano Hitoshi, Yamamoto Nozomi, Yamada Takuji
Corporate Strategy Office, Gurunavi, Inc., Toho Hibiya Building, 1-2-2 Yurakucho, Chiyoda-ku, Tokyo, 100-0006, Japan.
School of Life Science and Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8550, Japan.
Sci Rep. 2021 Jan 19;11(1):1791. doi: 10.1038/s41598-021-81105-x.
The microbial community during fermented vegetable production has a large impact on the quality of the final products. Lactic acid bacteria have been well-studied in such processes, but knowledge about the roles of non-lactic acid bacteria is limited. This study aimed to provide useful knowledge about the relationships between the microbiota, including non-lactic acid bacteria, and metabolites in commercial pickle production by investigating Japanese pickles fermented in rice-bran. The samples were provided by six manufacturers, divided into two groups depending on the production conditions. The microbiological content of these samples was investigated by high-throughput sequencing, and metabolites were assessed by liquid chromatography-mass spectrometry and enzymatic assay. The data suggest that Halomonas, halophilic Gram-negative bacteria, can increase glutamic acid content during the pickling process under selective conditions for bacterial growth. In contrast, in less selective conditions, the microbiota consumed glutamic acid. Our results indicate that the glutamic acid content in fermented pickle is influenced by the microbiota, rather than by externally added glutamic acid. Our data suggest that both lactic acid bacteria and non-lactic acid bacteria are positive key factors in the mechanism of commercial vegetable fermentation and affect the quality of pickles.
发酵蔬菜生产过程中的微生物群落对最终产品的质量有很大影响。乳酸菌在这类过程中已得到充分研究，但关于非乳酸菌作用的了解有限。本研究旨在通过调查在米糠中发酵的日本泡菜，提供有关包括非乳酸菌在内的微生物群与商业泡菜生产中代谢物之间关系的有用知识。样本由六家制造商提供，根据生产条件分为两组。通过高通量测序研究这些样本的微生物含量，并通过液相色谱 - 质谱联用和酶促测定评估代谢物。数据表明，嗜盐革兰氏阴性菌盐单胞菌在细菌生长的选择性条件下，可在腌制过程中增加谷氨酸含量。相反，在选择性较低的条件下，微生物群消耗谷氨酸。我们的结果表明，发酵泡菜中的谷氨酸含量受微生物群影响，而非外部添加的谷氨酸。我们的数据表明，乳酸菌和非乳酸菌都是商业蔬菜发酵机制中的积极关键因素，并影响泡菜的质量。
