Physiological and molecular characterisation of Saccharomyces cerevisiae cachac'a strains isolated from different geographic regions in Brazil

摘要

In this work, 74 Saccharomyces cerevisiae strains isolated from cachac'a fermentation of six different geographic regions in Brazil were characterized by mitochondrial DNA restriction fragment length polymorphism (mtDNA-RFLP) and by their ability to grow on stress conditions occurring during the cachac'a fermentation process. Cachac'a S. cerevisiae strains showed high mtDNA-RFLP polymorphism with the occurrence of 32 different molecular patterns. The S. cerevisiae strains presenting prevalent mtDNA were able to grow better in the stress conditions than strains represented by infrequent patterns. The principal coordinate analysis on 17 stress conditions revealed that the major source of growth variation were high ethanol concentrations and low temperatures. These results indicate that the stress conditions occurring in the fermentation process influence the prevalence of the most adapted S. cerevisiae strains in each distillery. The physiological tests used in our study can be used as a criterion for rapidly selecting autochthonous yeast strains for further purposes such as the selection of fermentative starters of S. cerevisiae strains.