Use of radiation in strains of Saccharomyces cerevisiae: A new technique for industrial applications

Rafael O. Andrette, João D. T. Arruda-Neto, Thiago O. Basso, Luiz Carlos Basso, Erika Cavalcante-Silva, Maria C. Bittencourt-Oliveira, Godofredo C. Genofre

CEPESq/Uniítalo-Italy-Brazilian University Center, S?o Paulo, Brazil.
Department of Biological Sciences, Luiz de Queiroz College of Agriculture/ESALQ, University of S?o Paulo, Piracicaba, Brazil.
Institute of Biosciences, University of S?o Paulo, S?o Paulo, Brazil.
Inter-Unities Graduation Program on Biotechnology, University of S?o Paulo, S?o Paulo, Brazil.
Laboratory of Cyanobacteria, ESALQ, University of S?o Paulo, S?o Paulo, Brazil.
Physics Institute, University of S?o Paulo, S?o Paulo, Brazil.

DOI: 10.4236/abb.2013.43045                

Abstract

During the industrial fermentation process in the production of fuel ethanol, yeasts are subject to several stressing conditions. The survival and the permanence of strains introduced in the process correlate with the capability of these yeasts in resisting to physical and chemical stresses, as well as their recovering ability to compete with contaminating micro-organisms commonly present in this industrial process. We aim at the selection of Saccharomyces cere visiae strains having this capability and ability. In this sense, cultivations of strains with industrial interest were irradiated with gammas ray at a wide dose interval. Growing curves for the strains were analyzed by means of their relative growth, a new concept here introduced, which allows a better understanding of the growing and recovering processes following radiative stress. It was found that gamma radiation could be used as an alternative method to quantify growing capabilities of S. cerevisiae strains under stressing conditions. It was also shown that this radiological method could be utilized as an additional procedure to select best robust industrial strains. This radiological method simplifies traditional analysis of strain viability, by avoiding the great number of necessary and consecutive fermentation assays.

Keywords

Saccharomyces cerevisiae; Industrial Yeast; Gamma Radiation; Evaluation Method; Industrial Fermentation; Ethanol

Conflicts of Interest

The authors declare no conflicts of interest.

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