Safety evaluation of the food enzyme endo-1,4-β-xylanase from genetically modified Aspergillus niger strain XYL

EFSA J. 2017 May 10;15(5):e04755. doi: 10.2903/j.efsa.2017.4755. eCollection 2017 May.

Abstract

The food enzyme considered in this opinion is an endo-1,4-β-xylanase (EC 3.2.1.8) produced with a genetically modified strain of Aspergillus niger. The genetic modifications do not give rise to safety concerns. The food enzyme contains neither the production organism nor recombinant DNA. The endo-1,4-β-xylanase is intended to be used in baking processes. Based on the maximum use levels recommended for the respective food process, dietary exposure to the food enzyme-total organic solids (TOS) was estimated on the basis of individual data from the EFSA Comprehensive European Food Consumption Database. This exposure estimate is below 0.013 mg TOS/kg body weight (bw) per day in European populations. No safety concerns were identified in relation to the genetic modifications performed, the manufacturing process, the compositional and biochemical data provided, allergenicity and exposure assessments. The allergenicity was evaluated by comparing the amino acid sequence to those of known allergens; no match was found. The Panel considered that the likelihood of allergic reactions to dietary intake of endo-1,4-β-xylanase is low and, therefore, does not give rise to safety concerns. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rodents. A no observed adverse effect level was derived (4,095 and 4,457 mg TOS/kg bw per day for males and females, respectively), which, compared with the dietary exposure, results in a sufficiently high margin of exposure. However, the genotoxicity data were incomplete. Due to the absence of the recommended combination of microbial strains used in the Ames test (i.e. lack of Salmonella Typhimurium TA102 and Escherichia coli WP2), no conclusions can be drawn on potential DNA oxidising or cross-linking mechanisms giving rise to gene mutations. Consequently, no final conclusions can be drawn on genotoxicity.

Keywords: 4‐β‐xylanase; Aspergillus niger; EC 3.2.1.8; endo‐1; food enzyme; genetically modified microorganism; xylanase.