Research Concerning Use of Long-Term Preservation Techniques for Microorganisms

Adriana Dalila Criste, Mihaela Giuburunca, Octavian Negrea, Sorin Dan, Marius Zahan


From the large number of methods used for storage of microorganisms, the more effective methods are long-term cryopreservation and lyophilization. The temperature change rate, controls transport of water around cell membranes and indirectly likelihood of intracellular freezing. If the cooling is too fast, the membranes cannot carry water out of the cell and freezing inside. Each cell has an optimum cooling rate, while the survival of very low absolute except that cryoprotector is present to reduce freezing damage.In the present study we proposed to determine the efficiency of some techniques on long term microorganisms conservation as cryopreservation and freeze-drying and the influence of cryoprotectants used in various concentrations on survival rate of bacterial strains during cryopreservtion at -80 ° C in freezer and - 196 ° C in liquid nitrogen. These 7 bacterial strains used for this work came from our collection of cultures, and are represented by Escherichia coli, Klebsiella pneumonie, Staphylococcus aureus, Bacillus cereus, Salmonella enterica., Pseudomonas aeruginosa, Lactobacillus casei. The cryoprotectant used are: dimethyl sulphoxide (DMSO) at a concentration of 5% and 10%, ethylene glycol (EG) at a concentration of 5% and 10%, glycerol(Gl) at a concentration of 5% and 10%, propylene glycol (PG) at a concentration of 5% to 10%.

Full Text:



Abadias, M., Teixido, N., Usall, J., Benabarre, A., Vinas, I., 2001. Viability, efficacy, and storage stability of freeze-dried biocontrol agent Candida sake using different protective and rehydration media. Journal of Food Protection 64 (6), 856–861.

Alexander, M.T., Simione, F.P.. 1980. Factors affecting the recovery of freeze-dried Saccharomyces cerevisiae. Abstracts of the Annual Meeting of the American Society for Microbiology, p. 86.

Crowe, J.H., Carpenter, J.F., Crowe, L.M., 1998. The role of vitrification in anhydrobiosis. Annual Review of Physiology 60 (1), 73–103.

Desmond, C., Ross, R.P, O'Callaghan, E., Fitzgerald, G., Stanton, C., 2002. Improved survival of Lactobacillus paracasei NFBC 338 in spray-dried powders containing gum acacia. Journal of Applied Microbiology 93, 1003–1011.

Hubalek, Z., 2003. Protectants used in the cryopreservation of microorganisms. Cryobiology 46, 205–229

Israeli, E., Shaffer, B.T., Lighthart, B., 1993. Protection of freeze-dried Escherichia coli by trehalose upon exposure to environmental conditions. Cryobiology 30, 519–523

Kleinhans, F. W., 1989. Membrane permeability modelling: Kedem-Katchalsky vs a two-parameter formalism. Cryobiology 37, 271–289

Leslie, S.B., Israeli, E., Lighthart, B., Crowe, J.H., Crowe, L.M., 1995. Trehalose and sucrose protect both membranes and proteins in intact bacteria during drying. Applied and Environmental Microbiology 61 (10), 3592–3597.

Nei, T., T. Araki, T. Matsusaka.1969. Freezing injury to aerated and non-aerated cultures of Escherichia coli. In T. Nei, Ed. Freezing and Drying of Microorganisms. University of Tokyo Press, Tokyo, Japan

Tao, D., Li, P.H., 1986. Classification of plant cell cryoprotectants, J. Theor. Biol. 123, 305–310.


  • There are currently no refbacks.

Copyright (c)

Scientific Papers Animal Science and Biotechnologies publish open access articles under the terms of the Creative Commons Attribution 4.0 Licence (read full legal code).


ISSN print 1841 - 9364
ISSN online 2344 - 4576
ISSN-L  1841 - 9364
(former ISSN 1221-5287, E-ISSN 1841-9364)

PAPER ACCESS: Full text articles available for free
FREQUENCY: Semiannual

Banat´s University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" from Timisoara
Bioengineering Faculty of Animal Resources
300645, Timişoara, Calea Aradului 119, Romania

E-mail: spasb [at]
Phone: +40-256-277160, Fax.: +40-256-277110