Objective: Studies conducted in microbiology laboratories with the inclusion of huge amount and variety of species and isolates are important indicators that render them valuable. For this purpose, each laboratory creates its own unique strain collection. For the sustainability of this procedure, the preferred storage method should be suitable for long-term storage of the isolates that keep the cells alive and stable. In this study, it was aimed to investigate the viability of Candida species in cold storage conditions at species level.

Method: The study included 94 stocks of Candida isolates obtained from clinical samples that had been stored in our laboratory for more than 10 years (in Cryobank vials with beads at -20°C) and had not undergone any recultivation or other recovery procedures during this period. Samples were passaged into liquid and solid media and recovered strains were confirmed with current routine diagnostic methods.

Results: The recovery rate of the study isolates was found 59.1% (13/22) for Candida parapsilosis, 41.7% (5/12) for Candida glabrata, 25% (4/16) for Candida tropicalis, and 9.52% (4/42) for Candida albicans. The recovery rate of C. parapsilosis isolates was found to be significantly higher compared to C. albicans and C. tropicalis isolates (p<0.0001 and p=0.037, respectively).

Conclusion: The data presented in this study support that C. parapsilosis isolates, which can survive at high temperatures, adapt to cold conditions and survive in hospital environments. They are also more stable under cold storage conditions than C. tropicalis C. glabrata, and especially C. albicans species.