Phytase

Phytase is the name of enzymes that degrade phytic acid hydrolysis, thus releasing the bound phosphate. Of course phytase occurs in a number of plants and micro-organisms, including the germ and the bran of cereal grains, but also in living in symbiosis with ruminant bacteria. Phytase makes the bound as an energy reserve in plant seeds available phosphorus and is therefore added to commercial pet food to an increasing extent.

Depending on which phosphate group is removed, a distinction is made between the 3 -, 4 -, 5 - and 6- phytase. The phytase formed by many plants and bacteria functions as a 3 -phytase ( EC 3.1.3.8 ), this is used commercially together with 6- phytase (EC 3.1.3.2 ). 4- phytase is an acid phosphatase ( EC 3.1.3.26 ) and 5 -phytase is not much known ( EC 3.1.3.72 ). The latter is able to cleave another phosphate to inositol triphosphate.

Use

Phytase is mainly used in the feed industry as an additive of feed to cleave the phytic acid occurring in plants and to make the phosphate contained available. This is especially necessary in the feeding of non- ruminant animals such as poultry and pigs, as otherwise the phosphate naturally present in plant food waste passes through the intestines and is excreted in the manure. By the use of phytase, the addition of inorganic phosphate may be reduced in the feed. Due to the better utilization also the waste water load is reduced by phosphate excreted in the manure and in manure.

Production

Phytase is especially biotechnology by fermentation of granulated sugar or alternative substrates, especially starch, won. As organisms genetically modified fungal cultures such as Aspergillus and Trichoderma species as well as the fission yeast are ( Schizosaccharomyces pombe ) are used.