Key Laboratory of Dairy Science, Ministry of Education, Northeast Agricultural University, Harbin 150030, Heilongjiang Province, China.
Food Funct. 2020 May 1;11(5):4571-4581. doi: 10.1039/c9fo03067k. Epub 2020 May 13.
Folate is an essential B vitamin and its deficiency is common in many parts of the world. Natural folate produced by microorganisms may be an alternative to chemically synthesized folic acid (FA) as a dietary supplement. Previously, two lactic acid bacteria (LAB) strains, a high folate-producing Lactococcus lactis subsp. lactis KLDS4.0325 and a weak folate-producing Lactococcus lactis subsp. lactis KLDS4.0613, were identified. The aim of this study was to evaluate the effect of milk fermented with L. lactis KLDS4.0325 (folate-enriched fermented milk, FEFM) in alleviating folate deficiency status using murine folate deficiency models. In addition, the link between gut microbiota diversity and folate levels in mice was investigated. Results showed that FEFM increased FA and 5-methyltetrahydrofolate (5-MTHF) concentrations in the whole blood and liver, and decreased plasma homocysteine (Hcy) levels. 16S rDNA sequence analysis also revealed that the supplementation of FEFM (containing 0.6 μg mL folate) and 0.6 μg d FA (FEFM + LFA) significantly improved the poor status of the gut microbiota composition caused by folate deficiency, and the effect was better than that with 1.2 μg d FA (HFA) supplementation. Our findings show that FEFM can be used as a folate-fortified food to alleviate folate deficiency effectively. In addition, it may be considered as a partial or total replacement for synthetic FA.
叶酸是一种必需的 B 族维生素，其缺乏在世界许多地区很常见。由微生物产生的天然叶酸可能是化学合成叶酸（FA）作为膳食补充剂的替代品。此前，我们鉴定了两株乳酸杆菌（LAB），一株是具有高叶酸生产能力的乳球菌乳亚种 KLDS4.0325，另一株是具有弱叶酸生产能力的乳球菌乳亚种 KLDS4.0613。本研究旨在利用鼠叶酸缺乏模型评估用乳球菌 KLDS4.0325 发酵牛奶（叶酸强化发酵乳，FEFM）缓解叶酸缺乏状态的效果。此外，还研究了肠道微生物多样性与小鼠叶酸水平之间的关系。结果表明，FEFM 增加了全血和肝脏中的 FA 和 5-甲基四氢叶酸（5-MTHF）浓度，并降低了血浆同型半胱氨酸（Hcy）水平。16S rDNA 序列分析还表明，FEFM（含 0.6μg mL 叶酸）和 0.6μg d FA（FEFM+LFA）的补充显著改善了叶酸缺乏引起的肠道微生物群落组成的不良状况，效果优于补充 1.2μg d FA（HFA）。我们的研究结果表明，FEFM 可用作叶酸强化食品，有效缓解叶酸缺乏。此外，它可以被认为是合成 FA 的部分或全部替代品。
