Opinion of the Scientific Panel on Additives and Products or Substances used in Animal Feed on the safety and efficacy of the product “Calsporin”, a preparation of Bacillus subtilis, as a feed additive for chickens for fattening in accordance with Regulation (EC) No 1831/2003

EFSA received a request from the Commission to assess the safety of the enzyme product Phytase SP 1002 for the target animals, the consumer, the user and the environment and the efficacy when used under the proposed conditions. Phytase SP 1002 is an enzyme preparation of 3-phytase, produced by the genetically modified micro-organism Hansenula polymorpha (DSM 15087). Phytase SP 1002 is intended to be used in piglets, pigs for fattening, sows, chickens for fattening, turkeys and laying hens. The recipient organism for the genetic modification is a yeast Hansenula polymorpha strain DSM 5215 derived from a wild type strain by isolation of a mutant requiring uracil. H. polymorpha is not pathogenic. The DNA vector used to transform this strain contained a synthetic phytase gene based on a consensus sequence, a URA gene from the non-pathogenic yeast Saccharomyces cerevisiae and the origin of replication of the Escherichia coli plasmid pBR322. Other sequences were from H. polymorpha or were synthetic linker molecules. The protein is encoded by a novel consensus sequence, but it is not expected that its functional properties are different from other phytases. A full sequence of the consensus phytase gene, a restriction map and list of elements in the vector used for transformation were provided by the applicant. Transformants were selected by uracil prototrophy. One of these transformants was chemically mutated to a strain that gave high yields of phytase, Hansenula polymorpha DSM 15087. The manufacturing process comprises the fermentation process, a purification process and the formulation and quality control procedures. The microbial cells are removed from the enzyme preparation by filtration and the absence of the production organism, H. polymorpha, from each enzyme batch is demonstrated. DNA from the production organism is below the limit of detection in the product. Data from efficacy trials demonstrates that Phytase SP 1002 is efficacious at the respective lowest recommended doses for piglets (500 U kg-1), pigs for fattening (250 U kg-1), sows (500 U kg-1), chickens for fattening (250 U kg-1), laying hens (250 U kg-1) and turkeys for fattening (250 U kg-1). Phytase SP 1002 used at ten times the maximum recommended dose was well tolerated by all the target species/categories tested. Therefore, safety for the target animals has been demonstrated. Phytase as present in Phytase SP 1002 is not mutagenic and did not show a toxic response of consumer relevance in a sub-chronic toxicity study. The FEEDAP Panel therefore considers the product of no concern for consumer safety. All the studies performed to assess user safety were based on a concentrated batch of the active substance phytase, but not on the final products. There was no evidence of skin and eye irritation or adverse effects occurring during inhalation when this concentrated phytase solution was used. As no sensitization study was provided the product should be regarded as potential sensitizer. The active substance is a 3-phytase which can be considered essentially similar to naturally occurring phytases. Phytases are proteins and are degraded in the gastrointestinal tract and the environment. Therefore, the FEEDAP Panel considers no further environmental assessment is required.