PCR-DGGE ANALYSIS OF THE YEAST POPULATION ASSOCIATED WITH NATURAL FERMENTATION OF TABERNA

Abstract

In this study, yeast community associated with the natural fermentation of Taberna, an alcoholic beverage made from palm sap, was determined using PCR-denaturing gradient gel electrophoresis (PCR-DGGE) of the D1 region of the 26S rRNA gene. This technique was complemented by cloning and sequencing of DGGE bands. The experiments were performed in triplicate. Each palm tree (palm tree I, II and III) represented an experimental unit. Fourteen batches from each palm tree were analyzed. These molecular methods allowed a rapid monitoring of yeast population associated with Taberna fermentation. Most frequent yeast species were Hanseniaspora guilliermondii, Saccharomyces cerevisiae and Pichia kudriavzevii (Issatchenkia orientalis), followed by Candida tropicalis and Kazachstania exigua. In addition, Meyerozyma guilliermondii, Candida akabanensis, Candida blattae, Candida intermedia, Pichia kluyveri and Trichosporon moniliiforme were also detected. In the first batches, only 5 yeast species were identified, from the second batch the number of species increased, in some batches ten yeast species were identified. The implementation of PCR-DGGE to describe yeast population in fermentation of Taberna revealed new members (C. akabanensis, C. blattae and T. moniliiforme) related with this palm wine. Results showed that PCR-DGGE is a good technique for characterizing yeast population structure. Findings allowed us gain important information about yeast community structure of Taberna fermentation.