L-isoleucine produced by fermentation with Corynebacterium glutamicum CGMCC 20437

In the current application an authorisation is sought under Article 4 for L-isoleucine produced by fermentation with Corynebacterium glutamicum CGMCC 20437, under the category/functional group 3(c) 'nutritional additives'/'amino acids, their salts and analogues', according to Annex I of Regulation (EC) No 1831/2003. The authorisation is sought for all animal species.
According to the Applicant, the feed additive contains L-isoleucine as an active substance with a minimum purity of 93.5 % (w/w, based on dry matter). The feed additive is intended to be added directly to compound feed or through premixtures and into water. However, the Applicant did not propose a minimum or maximum L-isoleucine content in compound feed.
For the determination of isoleucine in the feed additive and premixtures the Applicant proposed the ring-trial validated method EN ISO 17180 dedicated for the determination of free lysine, methionine and threonine in commercial amino acid products and premixtures. The method is based on ion-exchange chromatography (IEC) with optical (visible - VIS or fluorescence - FLD) detection. It does not distinguish between the salts of amino acids and cannot differentiate between enantiomers. This method is applicable for products containing more than 10 % of the amino acid.
The above mentioned method has been already evaluated and recommended by the EURL in the frame of the previous dossier (FAD-2019-0035) for the determination of free isoleucine in very similar feed additive and premixtures containing this additive. The EURL considers that this method is also applicable for the determination of isoleucine in the feed additive and premixtures of the current dossier.
Based on the available information, the EURL recommends for official control the ring-trial validated method EN ISO 17180 based on IEC-VIS/FLD for the determination of free isoleucine in the feed additive and premixtures.
For the determination of isoleucine in compound feed the Applicant proposed the ring-trial validated European Union (EU) method (Commission Regulation (EC) No 152/2009) based on ion-exchange chromatography with optical detection (IEC-VIS). This method is designed for the quantification of free (synthetic and natural) and of total (peptide-bound and free) amino acids in premixtures containing less than 10 % of the amino acid and compound feed, it does not distinguish between the salts of amino acids and cannot differentiate between enantiomers.
In addition, in the frame of the stability studies of L-isoleucine in the feed additive in water the Applicant provided experimental data demonstrating the applicability of the above mentioned EU method for the determination of isoleucine in the feed additive and water. Based on the performance characteristics available, the EURL recommends for official control the ring-trial validated European Union (EU) method, based on IEC-VIS to determine isoleucine in the feed additive, premixtures, compound feed and water.
In addition, the EURL recommends "L-isoleucine monograph" of the Food Chemical Codex monograph for the identification of L-isoleucine in the feed additive.
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, as last amended by Regulation (EU) 2015/1761) is not considered necessary.