title: Diversity and killer behaviour of indigenous yeasts isolated from the fermentation vat surfaces in four Patagonian wineries.
abstract: The diversity and killer behaviour of the yeast biota associated with surfaces of four Patagonian wineries were analyzed in the present study. These wineries were different in their technological and ecological features. Following liquid enrichment of samples from fermentation vat surfaces yeast isolates were identified by pheno- and genotyping and characterized using killer sensitivity patterns. Out of 92 isolated yeasts, 25% were Saccharomyces cerevisiae; 18% were Kloeckera apiculata and 11% were Pichia anomala; other six species representing a low percentage were also found. A particular biota composed mainly by S. cerevisiae (57%) and P. anomala (37%) was found in the winery located far from the other three wineries. As a whole, the wineries using spontaneous fermentation showed a major percentage of S. cerevisiae and a minor percentage of K. apiculata. The present study showed a pronounced heterogeneity in killer behaviour: killer, 35%, neutral, 25% and sensitive, 40%. In particular, S. cerevisiae isolates showed a higher sensitivity to killer reference yeasts than non-Saccharomyces isolates. On the other hand, most of the non-Saccharomyces yeasts isolated from fermentation vats were resistant to Saccharomyces toxins.
authors.affiliation: Departamento de Química, Laboratorio de Microbiología y Biotecnología, Facultad de Ingeniería, Universidad Nacional del Comahue, Buenos Aires, Neuquén, Argentina.
authors.forename: Marcela Paula
authors.initials: MP
authors.lastname: Sangorrín
authors.forename: Christian Ariel
authors.initials: CA
authors.lastname: Lopes
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Giraudo
authors.forename: Adriana Catalina
authors.initials: AC
authors.lastname: Caballero
mesh_terms: D001118:Argentina; D005285:Fermentation; D005838:Genotype; D007218:Industrial Microbiology; D055646:Killer Factors, Yeast; D009183:Mycotoxins / Q000494:pharmacology*; D010641:Phenotype; D010843:Pichia / Q000254:growth & development / Q000502:physiology; D012150:Polymorphism, Restriction Fragment Length; D012441:Saccharomyces cerevisiae / Q000254:growth & development / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins; D013045:Species Specificity; D014920:Wine / Q000382:microbiology*; D015003:Yeasts / Q000145:classification / Q000254:growth & development / Q000502:physiology*
chemical_list: D055646:Killer Factors, Yeast; D009183:Mycotoxins; D029701:Saccharomyces cerevisiae Proteins