head JofIMAB
Journal of IMAB - Annual Proceeding (Scientific Papers)
Publisher: Peytchinski Publishing Ltd.
ISSN: 1312-773X (Online)
Issue: 2021, vol. 27, issue4
Subject Area: Medicine
DOI: 10.5272/jimab.2021274.4038
Published online: 13 October 2021

Original article

J of IMAB. 2021 Oct-Dec;27(4):4038-4042
Neli Ermenlieva1ORCID logo Corresponding Autoremail, Emilia Georgieva2ORCID logo, Gabriela Tsankova1ORCID logo, Tatina Todorova1ORCID logo, Silvia Mihaylova4ORCID logo,
1) Department of Microbiology and Virology, Faculty of Medicine, Medical University – Varna, Bulgaria.
2) TRS Medical laboratory assistant, Medical College, Medical University-Varna, Bulgaria.
3) TRS Assistant Pharmacist, Medical College, Medical University of Varna, Bulgaria.

The low temperature in the storage processes can vary in the range of +4°C to -80°C and even lower, using liquid nitrogen. Depending on this, the time for which we expect the microbial culture to remain viable also changes. Agar slant culture, covered with oil, stab culture, saline suspension, glycerol and DMSO preservation, drying on silica gel, drying on soil, sterile water, lyophilization, cryopreservation, etc. are methods employed for the preservation of microorganisms. However, the choice of method to be used depends on the type of microorganism, the purpose of storage, and duration of preservation.
The aim of the study is to compare storage techniques using semisolid agar and cultivation at 4°C and using BHI broth with glycerol and cultivation at -20°C. These are two commonly used and accessible methods for bacteria and yeast preservation.
After performing the storage procedure for a total of 18 strains of S. aureus, E. coli and C. albicans, we re-cultivated them after two and six months of preservation.
From the obtained results, we can conclude that the storage of bacteria at 4°C on semisolid agar for up to 8 weeks is successful, in C. albicans, one of the tested six strains did not survive. After 6 months, another strain of the yeasts did not show growth, as well as one of the sixth E. coli strains.
Storing microbes at -20°C with a cryoprotectant has proven to be a more successful method. This was an expected result, and other authors commented that lower storage temperatures provide longer life for microorganisms.

Keywords: bacteria, yeast, optimal model, storage methods,

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Please cite this article as: Ermenlieva N, Georgieva E, Tsankova G, Todorova T, Mihaylova S. Suggestion for an optimal model for E.coli, S. aureus and C. albicans preservation at a storage temperature in the range of 4°C to -20°C. J of IMAB. 2021 Oct-Dec;27(4):4038-4042. DOI: 10.5272/jimab.2021274.4038

Corresponding AutorCorrespondence to: Neli Mitkova Ermenlieva, Department of Microbiology and Virology, Faculty of Medicine, Medical University – Varna; 3, Bregalniza Str., 9002 Varna, Bulgaria; E-mail: n.ermenlieva@abv.bg

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Received: 08 March 2021
Published online: 13 October 2021

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