3-phytase from Komagataella phaffii CECT 13171 (4a50): activity to EN ISO 30024 in the additive, premixtures and feed, 500 FTU/kg for poultry and pigs for fattening, 1000 FTU/kg for laying hens — authorised only after a second EFSA opinion with strain identification by WGS
Commission Implementing Regulation (EU) 2025/1392, published on 16 July 2025, authorises until 5 August 2035 a preparation of 3-phytase (EC 3.1.3.8) from the genetically modified strain Komagataella phaffii CECT 13171 (holder: Fertinagro Biotech S.L.) as a digestibility enhancer for poultry for fattening, reared for laying or for breeding, minor poultry species for breeding, laying hens and pigs for fattening of all Suidae. In its opinion of 27 September 2022 EFSA could not confirm the species of the strain or exclude viable cells in the product; only the opinion of 17 September 2024, based on the whole genome sequence and a new test, brought the strain under the QPS approach and found the additive safe.
- Method in the annex for the additive, premixtures and compound feed: colorimetric determination of phosphate released by phytase from phytate according to EN ISO 30024; 1 FTU is the amount of enzyme that releases 1 µmol of inorganic phosphate per minute from sodium phytate at 37 °C and pH 5.5. The EURL considered valid the conclusions of the earlier assessment of the same additive. Minimum activity: solid form 10 000 FTU/g, liquid 1000 FTU/ml. In the 2022 opinion EFSA gave 3-phytase the number EC 3.2.1.8 (the number of xylanase); the act gives EC 3.1.3.8.
- Composition (2022 opinion): solid FSF10000 — 1.2 % enzyme protein, 3–7 % sodium citrate, 88–92 % wheat bran; liquid FLF1000 — 1.2 g/l protein, 28–32 % sorbitol, sodium acetate and potassium sorbate. Five batches: 10 672 FTU/g (10 411–11 125) and 1070 FTU/ml (1008–1101). Metals, ochratoxin A, aflatoxins, DON, zearalenone, T-2, HT-2 and fumonisins below the LOQ; Enterobacteriaceae < 40 CFU/g, filamentous fungi up to 5.2 × 10² CFU/g or ml, Salmonella absent in 25 g. No recombinant DNA was detected by PCR (four genes, LOD 0.1–10 ng/g or ml).
- Reason for the second opinion: in 2022 identification relied on read mapping and analysis of the ITS alone, and in the viable-cell test it was unclear whether the positive control was a sample spiked with the strain. In 2024 the applicant submitted a phylogenomic analysis of four chromosomes (the strain clusters with two well-known strains — names redacted in the opinion) and a new test: 10 ml of intermediate product in 90 ml of YPD medium, 4 h at 30 °C, plating equivalent to 1 ml and incubation for up to 10 days at 25 °C, in three batches in triplicate — no growth.
- Minimum levels: 500 FTU/kg feed — poultry for fattening, reared for laying or for breeding, minor poultry species for breeding, pigs for fattening of all Suidae; 1000 FTU/kg — laying hens. The applicant proposed 375 FTU/kg for laying hens; in a new study apparent ileal phosphorus digestibility rose from 25.2 to 36.5 %, but the proportion of ash and phosphorus in the tibia did not change, so EFSA could not accept that level. The solid form is a skin sensitiser and both are potential respiratory sensitisers: respiratory and skin protection.