Phytic acid (known as inositol hexakisphosphate (IP6), or phytate when in salt form), discovered in 1903, is the principal storage form of phosphorus in many plant tissues, especially bran and seeds. Phytate is not digestible to humans or nonruminant animals, however, so it is not a source of either inositol or phosphate if eaten directly. Moreover, it chelates and thus makes unabsorbable certain important minor minerals such as zinc and iron, and to a lesser extent, also macro minerals such as calcium and magnesium.
Catabolites of phytic acid are called lower inositol polyphosphates. Examples are inositol penta- (IP5), tetra- (IP4), and triphosphate (IP3).
Read more about Phytic Acid: Significance in Agriculture, Biological and Physiological Roles, Food Science, Therapeutic Uses