phytate

Phytate, or phytic acid in its protonated form, is myo-inositol hexakisphosphate (IP6). It is the principal storage form of phosphorus in seeds and grains and occurs as various phytate salts with minerals, collectively called phytates. The molecule is highly negatively charged at physiological pH and readily forms complexes with multivalent cations such as calcium, iron, zinc, and magnesium.

Phytate is abundant in seeds, especially in bran and hull fractions of cereals, legumes, and oilseeds. In plants, phytate serves as a phosphorus reservoir for germination and early growth. It is stored in vacuoles and can be released as phosphate when phytases—enzymes that hydrolyze phosphoester bonds—act on the molecule during germination or processing.

Dietary implications are a major reason phytate is studied. In humans and many monogastric animals, phytate is poorly absorbed and can chelate minerals, reducing their bioavailability. Practices such as soaking, germination (sprouting), fermentation, and supplementation with microbial or cereal phytases can degrade phytate and improve mineral absorption. In animal nutrition, phytase enzymes are widely used as feed additives to enhance phosphorus utilization and reduce phosphorus excretion.

Industrial and environmental aspects include the use of phytases in food processing and animal feeds, and the persistence of phytate in soils where microbial phytases influence phosphorus cycling. While phytate has been explored for potential health benefits, including antioxidant activities, the overall view remains nuanced, with attention to balancing phosphorus nutrition and mineral bioavailability.

In summary, phytate is a biologically important plant storage compound with significant implications for nutrition, agriculture, and environmental phosphorus management.