QualiSud, Université de Montpellier, Avignon Université, CIRAD, Institut Agro, IRD, Université de la Réunion, 911 avenue Agropolis, 34394 Montpellier Cedex, France.
Center for Food Science and Nutrition, Addis Ababa University, Addis Ababa, Ethiopia.
Int J Food Microbiol. 2025 Jan 2;426:110909. doi: 10.1016/j.ijfoodmicro.2024.110909. Epub 2024 Sep 7.
Like in many developing countries, the traditional Ethiopian diet relies mainly on starchy staple foods and often lacks sufficient animal-sourced foods which are crucial for cobalamin intake. Furthermore, the concentration of folate in traditionally prepared injera, an Ethiopian cereal-based fermented staple food, is highly variable and injera contains biologically inactive corrinoids. This study aimed to improve the cobalamin and folate content of injera by using cobalamin-producing Propionibacterium freudenreichii and folate-producing Lactiplantibacillus plantarum strains, both individually and combined. Since injera is fermented using backslopping, we also assessed the ability of these strains to produce cobalamin and folate consistently across successive fermentation batches. Changes in the microbial ecosystem were monitored using real-time PCR. The theoretical contribution of the injera prepared using the selected strains to the cobalamin and folate intake of children and women of reproductive age was also calculated. Results showed that using the selected bacterial strains individually increased cobalamin (up to 19.2 μg/100 g of dry matter) and folate (up to 180.2 μg/100 g of dry matter) levels in the injera dough over several backslopping fermentation batches. Regular consumption of the injera with enhanced vitamin content produced using each strain alone would be capable of fulfilling the entire recommended nutrient intake for cobalamin and up to 29 % of the recommended intake for folate for children and women of reproductive age. However, when the strains were used together, the production of both vitamins was reduced. The presence of certain common endogenous bacterial species and genera exhibited significant variability, highlighting the complex response of the native microbiota to the different inoculation strategies employed. Future experiments should consider selecting a microbial consortium comprising non-competing microorganisms to ensure the simultaneous production of cobalamin and folate in fermented foods.
与许多发展中国家一样，传统的埃塞俄比亚饮食主要依赖淀粉类主食，往往缺乏足够的动物源食物，而这些食物对钴胺素的摄入至关重要。此外，传统制备的英吉拉（一种埃塞俄比亚基于谷物的发酵主食）中的叶酸浓度变化很大，并且英吉拉含有无生物活性的类钴胺素。本研究旨在通过使用产钴胺素的丙酸杆菌和产叶酸的植物乳杆菌单独和组合，来提高英吉拉中的钴胺素和叶酸含量。由于英吉拉是使用回槽发酵的，我们还评估了这些菌株在连续发酵批次中是否能够持续生产钴胺素和叶酸。使用实时 PCR 监测微生物生态系统的变化。还计算了使用选定菌株制备的英吉拉对儿童和育龄妇女的钴胺素和叶酸摄入量的理论贡献。结果表明，单独使用选定的细菌菌株可在几个回槽发酵批次中增加英吉拉面团中的钴胺素（高达 19.2μg/100g 干物质）和叶酸（高达 180.2μg/100g 干物质）含量。定期食用用每种菌株单独生产的强化维生素含量的英吉拉，将能够满足儿童和育龄妇女对钴胺素的全部推荐营养素摄入量，以及高达 29%的叶酸推荐摄入量。然而，当这些菌株一起使用时，两种维生素的产量都会降低。某些常见的内源性细菌种类和属的存在表现出显著的可变性，突出了天然微生物群对所采用的不同接种策略的复杂反应。未来的实验应考虑选择由非竞争微生物组成的微生物联合体，以确保发酵食品中同时生产钴胺素和叶酸。
