Safety evaluation of the food enzyme glucose oxidase from Aspergillus niger (strain ZGL)

Abstract

The food enzyme glucose oxidase (β-d-glucose:oxygen 1-oxidoreductase; EC 1.1.3.4) is produced with a genetically modified Aspergillus niger strain ZGL by DSM Food Specialties B.V. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and recombinant DNA. The glucose oxidase is intended to be used in baking processes. Based on the maximum use levels, dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 0.004 mg TOS/kg body weight (bw) per day. The toxicity studies were carried out with an asparaginase from A. niger (strain ASP). The Panel considered this enzyme as a suitable substitute to be used in the toxicological studies, because they derive from the same recipient strain, the location of the inserts are comparable, no partial inserts were present and the production methods are essentially the same. Genotoxicity tests did not raise 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 (NOAEL) at the highest dose of 1,038 and 1,194 mg TOS/kg bw per day (for males and females, respectively) that, compared with the estimated dietary exposure, results in a sufficiently high margin of exposure (MoE) (of at least 260,000). Similarity of the amino acid sequence to those of known allergens was searched 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, but the likelihood to occur is considered to be low. 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.