Characteristics of Phytase Enzyme and its Role in Animal Nutrition

Abstract

Cereals, legumes and oilseed crops are grown over 90% of the world’s harvested area. Together they serve as a major source of nutrients for the animal kingdom. An important constituent of seeds of these crops is phytic acid (myo-inositol 1, 2, 3, 4, 5, 6-hexakisphosphate; Ins P6). The salt form, phytate, is an anhydrous storage form of phosphate accounting for more than 80% of the total phosphorus in cereals and legumes. In contrast to other organo-phosphate molecules, phytate contains a high phosphate content, which results in a high negative charge over a wide pH range. Under normal physiological conditions phytic acid chelates essential minerals such as calcium, magnesium, iron and zinc. Phytic acid also binds to amino acids and proteins and inhibits digestive enzymes. Thus, phytic acid is an anti-nutritive component in plant-derived food and feed, and therefore, the enzymatic hydrolysis of phytic acid is desirable. The enzyme phytase is able to release the bioavailable phosphorus from phytic acid, consequently improving the phosphorus bioavailability and uptake of minerals.