Antioxidant properties of Rhodiola rosea

Brink, D. F.; Sapp, T. L.; Ghafoor, T. S.; Boyland, P. A.; Tamazawa, Y. C.; Kaur, G.; Shults, N. V.; Sullivan, R. D.; Suzuki, Y. J.

doi:10.64898/2026.05.21.726678

bioRxiv · 10.64898/2026.05.21.726678

Antioxidant properties of Rhodiola rosea

Brink, D. F.·Sapp, T. L.·Ghafoor, T. S.·Boyland, P. A.·Tamazawa, Y. C.·Kaur, G.·Shults, N. V.·Sullivan, R. D.·Suzuki, Y. J.

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Abstract

Rhodiola rosea is a traditional medicinal plant often classified as an adaptogen, with reported effects in supporting the bodys response to physical, environmental, and emotional stressors. The present study investigated the antioxidant properties of Rhodiola rosea extract and its major chemical constituents to provide insight into their potential mechanisms of action. Through in vitro biochemical assays, we demonstrated that Rhodiola rosea extract has the capacity to reduce hydrogen peroxide (H2O2) levels. Among its primary chemical components, rosavin significantly decreased H2O2, whereas salidroside had no effect. Neither compound affected superoxide levels. Structural analysis revealed that the intact phenylpropanoid glycoside architecture of rosavin is required for activity, as its individual components, arabinose and rosin, showed no inhibitory effect. Further investigation demonstrated that rosavin attenuates H2O2-mediated oxidation of thiol groups, supporting a role in cellular redox regulation. In cultured human cells, rosavin mitigated reductions in cell viability induced by exposure to H2O2, indicating cytoprotective effects under oxidative stress conditions. Finally, in an in vivo model, administration of SARS-CoV-2 spike protein increased circulating levels of H2O2, which were subsequently reduced following rosavin treatment. Collectively, these findings identify rosavin as a structurally dependent antioxidant component of Rhodiola rosea that modulates H2O2-associated oxidative stress and supports further investigation of phenylpropanoid glycosides as adaptogens.

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Brink, D. F., Sapp, T. L., Ghafoor, T. S., Boyland, P. A., Tamazawa, Y. C., Kaur, G., Shults, N. V., Sullivan, R. D., Suzuki, Y. J.. 2026-05-22. Antioxidant properties of Rhodiola rosea. https://doi.org/10.64898/2026.05.21.726678

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