Scientific Opinion on the safety and efficacy of L‐tryptophan, technically pure, produced by Escherichia coli strains DSM 25084, KCCM 11132P or SARI12091203 for all animal species based on a dossier submitted by AMAC EEIG

Safety and efficacy of the feed additive consisting of l-tryptophan produced by Escherichia coli KCCM 80210 for all animal species (Daesang Europe BV)

Following a request from the European Commission, the Panel on Additives and Products or substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of the feed additive consisting of l-tryptophan produced by fermentation with Escherichia coli KCCM 80210 when used as a nutritional additive in feed for all animal species and categories. The production strain E. coli KCCM 80210 is safe for the production of l-tryptophan and it was not detected in the final product. The Panel notes that two out of five batches of the additive do not comply with the minimum specification of 98% l-tryptophan on a dry matter basis proposed by the applicant. The use of l-tryptophan (≥ 98%) produced by E. coli KCCM 80210 in supplementing feed to compensate for l-tryptophan deficiency in feedingstuffs is safe for non-ruminant target species. There may be a risk for an increased production of toxic metabolites when unprotected l-tryptophan is used in ruminants. The use of l-tryptophan produced by E. coli KCCM 80210 in animal nutrition raises no safety concerns to consumers of animal products and to the environment. The additive under assessment is considered a mild eye irritant. The endotoxin activity of the additive and its dusting potential indicate a risk by inhalation for the users. The additive is not a skin irritant and is not a skin sensitiser. The additive l-tryptophan is regarded as an effective source of the amino acid l-tryptophan for all non-ruminant species. In order to be as efficacious in ruminants as in non-ruminants, it should be protected from ruminal degradation.

Safety and efficacy of l-tryptophan produced by fermentation with Escherichia coli KCCM 10534 for all animal species

Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on l-tryptophan produced by fermentation with a non-genetically modified strain of Escherichia coli KCCM 10534 when used as a nutritional additive in feed and water for drinking for all animal species and categories. The production strain E. coli KCCM 10534 is safe for the production of l-tryptophan and it was not detected in the final product. The use of l-tryptophan produced using E. coli KCCM 10534 in supplementing feed to compensate for tryptophan deficiency in feedingstuffs is safe for non-ruminant target species. There may be a risk for an increased production of toxic metabolites when unprotected tryptophan is used in ruminants. The FEEDAP Panel has concerns on the safety of the simultaneous oral administration of l-tryptophan via water for drinking and feed due to possible amino acid imbalances. The use of l-Tryptophan produced by E. coli KCCM 10534 in animal nutrition raises no safety concerns to consumers of animal products and to the environment. The additive under assessment is considered not toxic by inhalation, it is not a skin or eye irritant and is not a skin sensitiser. The endotoxin activity of the additive and its dusting potential indicate a risk by inhalation for the users. The product l-tryptophan is regarded as an effective source of the amino acid l-tryptophan for all non-ruminant species. In order to be as efficacious in ruminants as in non-ruminants, it should be protected from ruminal degradation.

Safety and efficacy of l-tryptophan produced by fermentation with Escherichia coli KCCM 80152 for all animal species

Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on l-tryptophan produced by fermentation using Escherichia coli KCCM 80152 when used as nutritional additive in feed and water for drinking for all animal species. The production strain and its recombinant DNA were not detected in the additive. l-Tryptophan, manufactured by fermentation with E. coli KCCM 80152, does not give rise to any safety concern with regard to the genetic modification of the production strain. The use of l-tryptophan produced using E. coli KCCM 80152 in supplementing feed to compensate for tryptophan deficiency in feedingstuffs is safe for non-ruminant target species. Using unprotected forms of tryptophan in ruminants can be a risk. The use of l-tryptophan produced by fermentation using E. coli KCCM 80152 in animal feed presents no concerns to consumers of animal products. Due to the content of endotoxins, the additive poses a risk for persons handling the additive when exposed by inhalation. The additive is not considered irritant for skin or eyes and is not considered a skin sensitiser. The additive under assessment is safe for the environment. The additive under assessment is regarded as an effective source of the amino acid l-tryptophan for all non-ruminant species. If l-tryptophan is intended for use in ruminants, it should be protected from ruminal degradation.

Safety and efficacy of l-tryptophan produced by fermentation with Escherichia coli CGMCC 7.248 for all animal species

Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on l-tryptophan produced by fermentation with a genetically modified strain of Escherichia coli CGMCC 7.248 when used as a nutritional additive in feed and water for drinking for all animal species and categories. The production strain E. coli CGMCC 7.248 and its recombinant DNA were not detected in the final product. The product l-tryptophan, manufactured by fermentation with E. coli CGMCC 7.248, does not give rise to any safety concern with regard to the genetic modification of the production strain. l-Tryptophan produced by E. coli CGMCC 7.248 is safe for non-ruminant target species. The use of unprotected l-tryptophan in ruminant feed should be avoided. l-Tryptophan produced by fermentation by E. coli CGMCC 7.248 is safe for the consumer. The level of endotoxins present in the product and its dusting potential indicate an inhalation risk for the user. l-Tryptophan produced by E. coli CGMCC 7.248 is not a skin or eye irritant but it is a dermal sensitiser. The use of l-tryptophan produced by E. coli CGMCC 7.248 in animal nutrition does not pose a risk to the environment. The product under assessment is regarded as an effective source of the amino acid l-tryptophan for all non-ruminant species. For the supplemental l-tryptophan to be as efficacious in ruminants as in non-ruminant species, it requires protection against degradation in the rumen.

Safety of l-tryptophan technically pure, produced by fermentation with Escherichia coli DSM 25084, KCCM 11132P and SARI12091203 for all animal species based on a dossier submitted by FEFANA Asbl

In 2015, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) issued an opinion on the safety and efficacy of l-tryptophan produced by fermentation using three strains of Escherichia coli, when used as a nutritional additive for all animal species. The Panel concluded that the safety of l-tryptophan produced by E. coli SARI12091203 for target animals, consumers, users and the environment could not be assessed because the data submitted did not permit the identity and safety of the strain, and the purity of the additive, to be determined. During the current assessment, the applicant withdrew the application for l-tryptophan produced by E. coli SARI12091203. l-Tryptophan produced by E. coli DSM 25084 or KCCM 11132P was considered safe for non-ruminant target species, the consumer and the environment. For both products, the level of endotoxins and the possible dusting potential indicated a risk by inhalation for the user. In the absence of data, a potential for dermal sensitisation could not be excluded. The Commission gave the applicant the possibility of submitting complementary information to allow the FEEDAP Panel to complete its assessment. The additional data on the characterisation of the additives and on their potential for inhalation toxicity and as skin sensitisers are the subject of the current opinion. Due to improvements in the manufacturing process, the level of endotoxins present in the l-tryptophan produced by E. coli KCCM 11132P has been markedly reduced; consequently, the endotoxin content does not represent a health risk for the user. The additive has a low acute toxicity by inhalation and is not considered as a potential skin sensitiser. l-Tryptophan produced by E. coli DSM 25084 is not considered a skin sensitiser. The level of endotoxins in this product, however, represents a risk by inhalation for the user handling the additive.