Safety evaluation of the food enzyme endo‐1,4‐β‐xylanase from a genetically modified Trichoderma reesei (strain DP‐Nzd22)

Abstract

The food enzyme xylanase (EC 3.2.1.8) is produced with the genetically modified Trichoderma reesei strain RF5703 by AB Enzymes GmbH. 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 food enzyme is intended to be used in brewing processes and grain treatment for the production of starch and gluten fractions. Since residual amounts of the food enzyme are removed during grain treatment, dietary exposure was only calculated for brewing processes. Based on the maximum recommended use levels for brewing processes, dietary exposure to the food enzyme–Total Organic Solids (TOS) was estimated to be up to 0.023 mg TOS/kg body weight (bw) per day. 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 at the highest dose tested of 1,000 mg TOS/kg bw per day, resulting in a high margin of exposure of at least 43,000. Similarity of the amino acid sequence to those of known allergens was searched and no match was found. The Panel considered that, under the intended condition of use, the risk of allergic sensitisation and elicitation reactions upon dietary exposure to this food enzyme cannot be excluded, but the likelihood of such reactions to occur is considered to be low. Based on the data provided and the removal of TOS during the intended food production process, the Panel concluded that this food enzyme does not raise safety concerns under the intended conditions of use.

Genetic engineering and raising temperature enhance recombinant protein production with the cdna1 promoter in Trichoderma reesei

“…The filamentous fungus Trichoderma reesei is widely used for cellulase production in industry, and the production level of secreted proteins was reported to be higher than 80 g/L (Bischof et al 2016 ; Fonseca et al 2020 ). In addition, T. reesei has been engineered for the production of other kinds of enzymes and pharmaceutical proteins (e.g., glucoamylase, endo-1,4-beta-xylanase and interferon (Bodie et al 2021 ; EFSA Panel on Food Contact Materials et al 2018 ; Landowski et al 2016 )). Consequently, the development of a powerful genetic toolbox and efficient fermentation processes are important for using T. reesei as a host of protein production.…”