Biotechnological production of food-grade polyphosphate from deoiled seeds and bran

Agricultural products, have a high phytate content that has a hidden potential as a renewable source of phosphate. We present the first biotechnological route for the production of food-grade, organic polyphosphate (polyP) from deoiled seeds or bran, included in a vision for a circular phosphorus economy. The three-step production process includes phosphorus mobilization (e.g., 37 mg PO43−/g bran) using phytase enzymes. Non-genetically modified phosphate starved Saccharomyces cerevisiae is then fed with soluble P-extracts. The yeast intracellularly polymerizes the phosphate to polyP (≥ 30 % mol polyP in yeast per mol PO43− in medium) and polyP-rich yeast extract or pure polyP is purified from the biomass. We demonstrate that the obtained polyP-rich yeast extract is an excellent green surrogate for polyP from fossil P-sources in meat manufacturing. The valorization of phytate–P while producing P-depleted biomass as a demanded feed in livestock production is shown. Our sustainable process enables the production of food-grade polyP from renewable resources and is contributing to the sustainable management of the dwindling nutrient phosphorus.