Development of heme iron-enriched functional foods to combat iron deficiency anemia (HemI-EFF)

The aim of our project is to efficiently and in large amounts produce plant hemoglobins (PHbs) in Nicotiana benthamiana and probiotic bacteria. The PHbs can then be used to prevent and alleviate iron deficiency anemia (IDA) in humans.

IDA is the only nutrient deficiency that is prevalent in all countries and is one of the most common nutritional disorders affecting an estimated 2 billion people. Though heme iron (heme-Fe) from meat can be absorbed very efficiently in humans, consumption of heme-Fe is constrained by several factors, such as affordability, personal preference, religion, or government policy. Moreover, recent studies emphasize a strong relationship between high consumption of meat products and increased risk for severe diseases such as cancer or cardiovascular disease. The world's meat production is also considered non-sustainable from a global warming perspective since cattle emit enormous amounts of greenhouse gases. Instead, inorganic Fe is widely used to reduce IDA using oral intake of inorganic Fe-salts. However, long-term use of oral Fe supplementation gives rise to side effects, such as stomach pain, nausea, diarrhea, vomiting and constipation.

Therefore, there is an urgent need to develop a more sustainable product, of vegetable origin, that makes a much smaller environmental footprint. Plant-based Heme-Fe products therefore are much more sustainable and with a much smaller environmental impact, thus being highly suitable as a Heme-Fe source. In the proposed project, we have built a project team that is both highly competent and suitable or a project where we want to produce PHbs through combinatorial overexpression of PHbs in plants and probiotic bacteria. In a preliminary experiment we have already managed to increase the level of heme-Fe production in Nicotiana benthamiana 40-fold by targeting plant globins into multiple organelles and we now want to further increase Fe production in plants by individual or combinatorial overexpression of major genes in the heme biosynthetic pathway along with co-overexpression of globins. Then, we want to extract and purify the PHbs in a usable form as Fe-fortificant or as a constituent in plant-based food.

In parallell, we express PHbs in the heme producing probiotic bacterium Bacillus coagulans with the aim to also develop a probiotic but plant-based product that can be used for IDA prevention and alleviation. We will also assess the bioavailability of purified PHbs and PHB-producing probiotics using a human epithelial Caco-2 in vitro assay and uptake from the mouse gastrointestinal tract.