Investigation of the Antioxidant Properties of the Quaternized Chitosan Modified with a Gallic Acid Residue Using Peroxidase that Produces Reactive Oxygen Species

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Dmitry B. Kiselevsky^1,a*, Alla V. Il’ina², Alexey P. Lunkov², Valery P. Varlamov², and Vitaly D. Samuilov¹

¹Department of Immunology, Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia

²Laboratory of Biopolymer Engineering, Skryabin Institute of Bioengineering, Research Center of Biotechnology, Russian Academy of Sciences, 119071 Moscow, Russia

^* To whom correspondence should be addressed.

Received November 10, 2021; Revised December 15, 2021; Accepted December 22, 2021

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Chitosan modified with a (2-hydroxy-3-trimethylammonium) propyl group and gallic acid residue, or quaternized chitosan with gallic acid (QCG), was synthesized. Antioxidant properties of the produced QCG have been investigated. Peroxidase in combination with NADH and salicyl hydroxamate (SHAM) caused consumption of oxygen and production of H₂O₂ in aqueous solution as a result of O₂ reduction in the peroxidase–oxidase reactions. The rates of O₂ consumption and H₂O₂ generation were reduced in the presence of QCG. The antioxidant propyl gallate (PG) and superoxide dismutase (SOD) had the same effect, but not the quaternized chitosan (QC) without gallic acid. The effect of chitosan derivatives on the production of reactive oxygen species (ROS) in the cells of pea leaf epidermis and on the cell death detected by the destruction of cell nuclei, was investigated. QCG, QC, and SOD had no effect, while PG decreased the rate of ROS generation in the cells of the epidermis, which was induced by NADH with SHAM or by menadione. QCG and QC prevented destruction of the guard cell nuclei in the pea leaf epidermis that was caused by NADH with SHAM or by KCN. SOD had no effect on the destruction of nuclei, while the effect of PG depended on the inducer of the cell death. Suppression of the destruction of guard cell nuclei by chitosan derivatives was associated not with their antioxidant effect, but with the disruption of the plasma membrane of the cells. The results obtained have shown that QCG exhibits antioxidant properties in solutions, but does not prevent generation of ROS in the plant cells. The mechanism of antioxidant effect of QCG is similar to that of PG and SOD.

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KEY WORDS: chitosan, quaternized chitosan, peroxidase, superoxide dismutase, reactive oxygen species, propyl gallate

DOI: 10.1134/S0006297922020067

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