THEORETICAL JUSTIFICATION OF AN EFFECTIVE CRYOPRESERVATION PROTOCOL OF CANDIDA YEASTS AND EXPERIMENTAL VERIFICATION OF THE MATHEMATICAL MODELING RESULTS

摘要

This study is dedicated to the development, theoretical and experimental substantiation of an effective cryopreservation protocol for yeasts Candida albicans. The dependence of effective cooling rate from intracellular processes of crystal formation during the C. albicans freezing in dimethyl sulfoxide (DMSO) solution was estimated theoretically. The calculated value was approximately 7℃/min. The results were confirmed by field experiments. An efficient protocol for C. albicans yeasts cryopreservation regimen was created, whereby a cell suspension in 5% DMSO or glycerol solution is cooled at a rate from 3.5 to 7℃/min up to -40℃ with further plunging into liquid nitrogen. This mode ensures the safety of the cells viability at 90%. It was shown that the C. albicans long-term storage in low temperature bank at a constant temperature did not result to additional cell death.