Comparative study of non-Saccharomyces microflora of musts in fermentation, by physiological and molecular methods

Non-Saccharomyces yeast isolates from musts of AC (Appellation Controlee) L a Mancha in spontaneous fermentation were comparatively identified by physi ological and molecular tests. The criterion of Barnett for the phenotypic i dentification was followed. Genetic characterization by polymerase chain re action (PCR)/restriction fragment length polymorphism (RFLP) was made. The region between 18S and 28S rRNA genes was amplified using specific internal transcribed spacers ITS1 and ITS4 primers. The 47 non-Saccharomyces isolat es produced nine different phenotypic profiles and 13 different genetic pro files, showing that PCR/RFLP can be more discriminating. The information su pplied by the two methodologies was very similar. PCR/RFLP can be used to c orrect erroneous identifications by phenotype, and in some cases to achieve intra-species differentiation. (C) 1999 Federation of European Microbiolog ical Societies. Published by Elsevier Science B.V. All rights reserved.