BIODIVERSITY STUDIES ON Pichia kudriavzevii FROM ROMANIAN SPONTANEOUS FERMENTED PRODUCTS

Abstract

Yeasts represent a major group within the microbial communities involved in production of fermented foods. Studies regarding yeast diversity during fermentation, focused on Saccharomyces cerevisiae, but Pichia kudriavzevii also represents an important component of these communities. P. kudriavzevii is widely distributed in nature, is isolated mainly from natural fermentations and is characterised as a potential biocontrol and wastewater treatment agent. The present work deals with biodiversity studies on four P. kudriavzevii strains from Romanian spontaneous fermented products. The strains were identified using conventional tests and molecular analyses of the rDNA coding region. The intraspecific biodiversity was evaluated by PCR-RAPD using different primers. The dynamics of yeast communities from fermented products involved interspecific comparative analysis of RAPD profiles of our strains and their cofermenters and determination of the similarity index using the Jaccard coefficient (Sij). This study represents a preliminary step for characterizing the microbial communities from Romanian fermented products and is essential for the improvement of biotechnological processes associated with food industry.