Safety evaluation of the food enzyme glucan 1,4‐α‐maltotetraohydrolase from Bacillus licheniformis (strain DP‐Dzf24)

food enzyme, glucan 1, 4-a-maltotetraohydrolase EC,Bacillus licheniformis, DP-Dzf24, genetically modified microorganism
First published in the EFSA Journal
14. Juni 2019
22. Mai 2019
Scientific Opinion

The full opinion will be published in accordance with Article 12 of Regulation (EC) No 1331/2008 once the decision on confidentiality will be received from the European Commission.


The food enzyme glucan 1,4‐α‐maltotetraohydrolase (EC is produced with the genetically modified Bacillus licheniformis strain DP‐Dzf24 by Danisco US Inc. The production strain contains multiple copies of a known antimicrobial resistance gene. However, based on the absence of viable cells and DNA in the food enzyme, this is not considered to be a risk. The food enzyme is intended to be used in baking processes and starch processing for the production of glucose syrups. The residual amounts of the Total Organic Solids (TOS) in glucose syrups are removed by filtration and purification during starch processing. Consequently, dietary exposure was not calculated for this use. Based on the maximum use levels recommended for the baking processes and individual data from the EFSA Comprehensive European Food Consumption Database, dietary exposure to the food enzyme–TOS was estimated to be up to 0.271 mg TOS/kg body weight per day in European populations. Toxicological tests with the food enzyme indicated that there was no concern with respect to genotoxicity or systemic toxicity. A no‐observed‐adverse‐effect level (NOAEL) was identified in rats, which, compared with the dietary exposure, results in a margin of exposure of at least 347. The allergenicity was evaluated by searching for similarity of the amino acid sequence to those of known allergens; no match was found. The Panel considers that, under the intended conditions of use, the risk for allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood is considered low. Based on the microbial source, genetic modifications, the manufacturing process, the compositional and biochemical data, the dietary exposure assessment and the findings in the toxicological studies, the Panel concludes that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Panel members at the time of adoption

José Manuel Barat Baviera, Claudia Bolognesi, Beat Johannes Brüschweiler, Andrew Chesson, Pier Sandro Cocconcelli, Riccardo Crebelli, David Michael Gott, Konrad Grob, Evgenia Lampi, Alicja Mortensen, Gilles Rivière, Vittorio Silano, Inger‐Lise Steffensen, Christina Tlustos, Henk Van Loveren, Laurence Vernis and Holger Zorn.
Panel on Food Contact Materials, Enzymes and Processing Aids
fip [at]
EFSA Journal 2019;17(6):5739
Question Number
On request from
European Commission