# Safety evaluation of the food enzyme endo‐1,4‐β‐xylanase from the non‐genetically modified Trichoderma citrinoviride strain X31

**Authors:** Holger Zorn, José Manuel Barat Baviera, Claudia Bolognesi, Francesco Catania, Gabriele Gadermaier, Ralf Greiner, Baltasar Mayo, Alicja Mortensen, Yrjö Henrik Roos, Marize L. M. Solano, Monika Sramkova, Henk Van Loveren, Laurence Vernis, Andrew Chesson, Lieve Herman, Natália Kovalkovičová, Magdalena Andryszkiewicz, Daniele Cavanna, Simone Lunardi, Yi Liu

PMC · DOI: 10.2903/j.efsa.2025.9482 · 2025-06-24

## TL;DR

This study evaluates the safety of a food enzyme produced by a non-genetically modified fungus and concludes it is safe for use in food manufacturing.

## Contribution

The study provides a comprehensive safety assessment of endo-1,4-β-xylanase from Trichoderma citrinoviride strain X31 for food use.

## Key findings

- Genotoxicity tests showed no safety concerns for the food enzyme.
- The no observed adverse effect level was 2210 mg TOS/kg bw per day, with a margin of exposure of at least 3279.
- No homology to known allergens was found, though a low risk of allergic reactions cannot be excluded.

## Abstract

The food enzyme endo‐1,4‐β‐xylanase (4‐β‐d‐xylan xylanohydrolase; EC 3.2.1.8) is produced with the non‐genetically modified microorganism Trichoderma citrinoviride strain X31 by Shin Nihon Chemical Co., Ltd. The food enzyme was considered free from viable cells of the production organism. It is intended to be used in nine food manufacturing processes. Since residual amounts of food enzyme–total organic solids (TOS) are removed in two processes, dietary exposure was calculated for the remaining seven food manufacturing processes. It was estimated to be up to 0.674 mg TOS/kg body weight (bw) per day in European populations. 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 2210 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 3279. A search for the homology of the amino acid sequence of the endo‐1,4‐β‐xylanase to known allergens was made and no match was found. The Panel considered that a risk of allergic reactions upon dietary exposure cannot be excluded, but that the likelihood is 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.

## Linked entities

- **Species:** Trichoderma citrinoviride (taxon 58853), Rattus norvegicus (taxon 10116)

## Full-text entities

- **Diseases:** toxicity (MESH:D064420), allergic reactions (MESH:D004342)
- **Species:** Trichoderma citrinoviride (species) [taxon 58853], Rattus norvegicus (brown rat, species) [taxon 10116]

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Source: https://tomesphere.com/paper/PMC12185997