Safety evaluation of the food enzyme β-galactosidase from the genetically modified Bacillus licheniformis strain NZYM-BT

EFSA J. 2022 Jul 4;20(7):e07358. doi: 10.2903/j.efsa.2022.7358. eCollection 2022 Jul.

Abstract

The food enzyme β-galactosidase (β-d-galactoside galactohydrolase; EC 3.2.1.23) is produced with the genetically modified Bacillus licheniformis strain NZYM-BT by Novozymes A/S. The genetic modifications do not give rise to safety concerns. The production strain has been shown to qualify for the qualified presumption of safety (QPS) status. The food enzyme was considered free from viable cells of the production organism and its DNA. It is intended to be used in milk processing for the hydrolysis of lactose. Based on the assumption that all selected milk and milk products are enzymatically treated, dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 0.34 mg TOS/kg body weight (bw) per day in European populations. Toxicological data were reported and were considered as supporting evidence of the safety of the food enzyme. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 672 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, results in a margin of exposure above 1,950. A search for similarity of the amino acid sequence of the food enzyme to known allergens was made and one match was found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, especially in individuals sensitised to galactosidase or to the matching allergen of pollen from Platanus. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Keywords: Bacillus licheniformis; EC 3.2.1.23; food enzyme; genetically modified microorganism; β‐d‐galactoside galactohydrolase; β‐galactosidase.