title: Performance of Seven Commercial Phytases in an in Vitro Simulation of Poultry Digestive Tract.
abstract: The aim of this study was to compare the biochemical properties of seven commercially available phytase products as well as their catalytic performance in an in vitro simulation of the digestive tract of poultry. Their enzymatic properties relevant with respect to phytate dephosphorylation in the digestive tract of birds were determined under identical assay conditions. All phytase products included in the study showed an acid pH optimum of activity and were capable of releasing the organically bound phosphate from phytate during the in vitro simulation. However, their overall biochemical properties and relative catalytic performances were remarkably different. The in vitro degradation system was considered as a simple and useful tool to evaluate the suitability of a phytase to be used as a feed supplement. Although relevant factors such as dietary P levels, intestinal phytase, and P absorption are not implemented in the system, this approach might help to reduce the number of feeding trials necessary in the search for a better suited phytase for animal feeding application.
authors.affiliation: Department of Food Technology and Bioprocess Engineering, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, Karlsruhe, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Menezes-Blackburn
authors.affiliation: Department of Food Technology and Bioprocess Engineering, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, Karlsruhe, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Gabler
authors.affiliation: Department of Food Technology and Bioprocess Engineering, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, Karlsruhe, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Greiner
mesh_terms: D010832:6-Phytase / Q000737:chemistry / Q000378:metabolism*; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D055162:Biocatalysis; D002645:Chickens; D019587:Dietary Supplements / Q000032:analysis; D004063:Digestion; D041981:Gastrointestinal Tract / Q000201:enzymology / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008954:Models, Biological; D016226:Phosphorus, Dietary / Q000378:metabolism; D010833:Phytic Acid / Q000378:metabolism; D011200:Poultry
chemical_list: D016226:Phosphorus, Dietary; D010833:Phytic Acid; D010832:6-Phytase
keywords: in vitro degradation system; phytase; phytate dephosphorylation