Biotesting of deep eutectic solvents using phytotest and Allium test

Introduction. Biotesting can be used to assess the safety of various chemicals.

The aim of the study was to evaluate the toxicity of deep eutectic solvents: choline chloride+glycerol+water, choline chloride+citric acid+water, and citric acid+glycerol+water using phytotest and Allium test.

Materials and methods. The research methods included phytotesting carried out on test crops of Sinapis alba L. and Avena nuda L. according to the standard method with root length measurement after experimental exposure for 72 hours and calculation of the of the phytoinhibitory effect (PIE,%) and Allium test with germination of bulbs in solutions for 96 hours.

Results. At a 10% concentration, all DESs exhibited toxicity. [ChCl][Gly]₂[H₂O]₁₁ at 1% and 0.1% concentrations showed weak to moderate phytotoxicity, with growth inhibition by 38% and 34% in S. alba and 33% and 35% in A. nuda. [ChCl][Cit]₂[H₂O]₄₃ and [Cit][Gly]₄[H₂O]₂₀ at 0.1% concentration also demonstrated weak phytotoxicity, with growth inhibition by 34% and 50% in S. alba and 43% and 26% in A. nuda, respectively. The Allium test revealed toxic effects for all DESs, except [ChCl][Gly]₂[H₂O]₁₁ at 1% and 0.1% and [ChCl][Cit]₂[H₂O]₄₃ at 0.1%, where no significant toxicity was observed. A statistically significant decrease in the mitotic index and the occurrence of chromosomal stickiness were noted in the Allium test.

Limitations. Use of only plant objects for toxicity assessment.

Conclusion. [ChCl][Gly]₂[H₂O]₁₁ exhibited weak to moderate toxicity, consistent with existing literature. These findings can guide the development of safety assessment methods for DESs in industrial applications.

Compliance with ethical standards. The study does not require the submission of a biomedical ethics committee opinion or other documents.

Contribution:
Smirnova M.V. – the concept and design of the study, collection and processing of the material, statistical processing, writing text;
Koigerova A.A. – the concept and design of the study, collection and processing of the material, statistical processing, writing text;
Tsvetov N.S. – writing text.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. This work was carried out within the frameworks of Research Contracts No. FMEZ-2025-0064.

Received: July 4, 2025 / Revised: July 22, 2025 / Accepted: March 24, 2026 / Published: May 18, 2026

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