Microalgae cryopreservation techniques: choosing cryoprotectants and cooling regimens

Authors

  • Nadiia A. Chernobai Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine; National Scientific Center «Ноn. Prof. М.S. Bokarius Forensic Science Institute», Kharkiv, Ukraine https://orcid.org/0000-0002-5736-9277
  • Anton P. Gerilovych Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine; One Health Scientific and Research Institute, Kharkiv, Ukraine https://orcid.org/0000-0002-3280-4172
  • Nadiia O. Shevchenko Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine https://orcid.org/0000-0001-6794-1444

Keywords:

microalgae, cryoprotectants, cryopreservation regimes, plant vitrification solutions, low temperature storage

Abstract

This review was aimed to summarize and array current methods to cryopreserve microalgae, particularly, the approaches to selecting cryoprotectants and optimal cooling parameters, aimed at preserving their viability and functional activity after thawing. The paper analyses the key aspects of cryopreservation of microalgae, including the efficiency comparison of different classes of cryoprotectants as well as their impact on cells; mechanisms of cryodamage and strategies for minimizing it; optimal cooling and warming regimens for various types of microalgae. Special attention has been paid to the dependency of cryopreservation efficiency on the concentration and composition of cryoprotective solutions, which vary depending on the specific species and cultures. Some microalgae has been noted to maintain high viability using elevated concentrations of non-penetrating cryoprotectants. The necessity for further research using new and combined cryoprotective solutions has been emphasized to expand the possibilities of long-term storage of microalgae.

Probl Cryobiol Cryomed. 2026; 36(1): 5—15

Author Biographies

Nadiia A. Chernobai, Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine; National Scientific Center «Ноn. Prof. М.S. Bokarius Forensic Science Institute», Kharkiv, Ukraine

Laboratory of  Phytocryobiology

Anton P. Gerilovych, Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine; One Health Scientific and Research Institute, Kharkiv, Ukraine

Department of Cryomicrobiology

Nadiia O. Shevchenko, Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine

Laboratory of  Phytocryobiology

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Published

2026-05-24

How to Cite

Chernobai, N., Gerilovych, A., & Shevchenko, N. (2026). Microalgae cryopreservation techniques: choosing cryoprotectants and cooling regimens. Problems of Cryobiology and Cryomedicine, 36(1), 5–15. Retrieved from https://cryo.org.ua/journal/index.php/probl-cryobiol-cryomed/article/view/2179