RESUMEN
The aims of this work was to characterise indigenous Saccharomyces cerevisiae strains in the naturally fermented juice of grape varieties Cabernet Sauvignon, Grenache, Tempranillo, Sauvignon Blanc and Verdejo used in the São Francisco River Valley, northeastern Brazil. In this study, 155 S. cerevisiae and 60 non-Saccharomyces yeasts were isolated and identified using physiological tests and sequencing of the D1/D2 domains of the large subunit of the rRNA gene. Among the non-Saccharomyces species, Rhodotorula mucilaginosa was the most common species, followed by Pichia kudriavzevii, Candida parapsilosis, Meyerozyma guilliermondii, Wickerhamomyces anomalus, Kloeckera apis, P. manshurica, C. orthopsilosis and C. zemplinina. The population counts of these yeasts ranged among 1.0 to 19 × 10(5) cfu/mL. A total of 155 isolates of S. cerevisiae were compared by mitochondrial DNA restriction analysis, and five molecular mitochondrial DNA restriction profiles were detected. Indigenous strains of S. cerevisiae isolated from grapes of the São Francisco Valley can be further tested as potential starters for wine production.
Asunto(s)
Biodiversidad , Vitis/microbiología , Levaduras/clasificación , Levaduras/aislamiento & purificación , Brasil , Recuento de Colonia Microbiana , ADN de Hongos/química , ADN de Hongos/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Técnicas de Tipificación Micológica , Polimorfismo de Longitud del Fragmento de Restricción , ARN Ribosómico/genética , Análisis de Secuencia de ADN , Levaduras/genéticaRESUMEN
Twenty-eight Candida albicans strains obtained from women with vaginal candidiasis were tested for phospholipase and proteinase production and clustered by multilocus enzyme electrophoresis (MLEE). The proteolytic and phospholipidic activity were considered moderate (0.56 ± 0.12 mm and 0.53 ± 0.09 mm, respectively) for all isolates. The isoenzymes malate dehydrogenase (MDH) and sorbitol dehydrogenase (SDH) showed strong intra-specific discriminatory power. The numerical and genetic interpretation of the bands produced by the isoenzymes tested presented similar discriminatory power. The genetic diversity of the isolates was measured by allelic and genic frequency, perceptual index of polymorphic loci (P = 87.5%), average number of alleles per locus, average number of alleles per polymorphic locus, average heterozygosity observed and average heterozygosity expected. We verified that three isoenzymatic loci (Adh, Gdh and Sdh-2) were not in Hardy-Weinberg equilibrium. A dendrogram constructed based on the genetic distance matrix of Nei showed seven clusters; 57.15% (16) of the isolates were considered highly related or indistinguishable, and 42.85% were considered moderately related or unrelated. We did not find a relationship between the clusters and the exoenzymes production.