- Fecha de publicación
- 23 junio 2014 (Última actualización el: 6 junio 2016)
For the quantification of 6-phytase activity in the feed additive:
- colorimetric method based on the enzymatic reaction of phytase on the phytate
For the quantification of 6-phytase activity in premixtures and feedingstuffs:
- colorimetric method based on the enzymatic reaction of phytase on the phytate EN ISO 30024
In the current application authorisation is sought under article 4(1) for Axtra® Phy 15000L, under the category/functional 4(a) "zootechnical additives"/"digestibility enhancers" according to the classification system of Annex I of Regulation (EC) No 1831/2003. Specifically, authorisation is sought for the use of the feed additive for chickens and turkeys for fattening, chickens reared for laying, turkeys reared for breeding, turkeys for breeding purposes, laying hens, minor avian species, weaned piglets, pigs for fattening, sows for reproduction, and minor porcine species. The active agent of Axtra® Phy 15000L is 6-phytase (EC 188.8.131.52), produced by fermentation of Trichoderma reesei. According to the Applicant, Axtra® Phy 15000L is a liquid preparation with a guaranteed minimum enzyme activity of 15000 U/g. It is intended to be used in premixtures and/or complete feedingstuffs to obtain 6-phytase activities ranging from 250 to 2000 U/kg feedingstuffs. The Applicant uses the international phytase unit defined in the EN ISO 30024, where "one phytase unit (U) is the amount of enzyme which releases one micromole of inorganic phosphate from sodium phytate per minute at pH 5.5 and 37°C". For the determination of phytase in the feed additive, premixtures and feedingstuffs, the Applicant submitted colorimetric methods derived from the EN ISO 30024 standard method. Phytase is incubated with sodium phytate, resulting in the release of inorganic phosphate and forming a yellow complex with an acidic molybdate/vanadate reagent. Based on the experimental data available, the EURL recommends for official control the in-house validated and further verified method for the quantification of phytase activity in the feed additive and the EN ISO 30024 standard method for the quantification of phytase activity in premixtures and feedingstuffs. Further testing or validation of the methods to be performed through the consortium of National Reference Laboratories as specified by Article 10 (Commission Regulation (EC) No 378/2005) is not considered necessary.