Development of a model-wine media to evaluate Dekkera bruxellensis growth in mimic wine conditions

STURM M.E.; ROJO M.C.; CIKLIC I.; RAMIREZ, M.L.; COMBINA M.

Puerto Madryn, Argentina

Otro; 46th Annual Meeting of Argentine Society for Biochemistry and Molecular Biology Research; 2010

In recent years, Dekkera bruxellensis has caused increasingly severe quality problems in the wine industry associated with volatile phenols production. Thus, a better understanding of Dekkera’s growth and metabolism will facilitate its control and manipulation, preventing the development of undesirable flavour changes. To examine the impact of several wine compounds on the growth and the formation of volatile phenols, it is very important to have a chemically defined medium that mimics the wine’s composition and that is reproducible under experimental conditions. However, the design of such medium is a challenge, considering that Dekkera yeasts have very restricted and not well known requirements for growth. The aim of this work was to optimize the biomass production and to evaluate several culture media of different composition for its ability to support the growth of D. bruxellensis. For the biomass pre-inoculum optimization, the best result was obtained in presence of wine. We assayed four different wine-like culture media, which included variations in sugar, vitamin, ethanol and nitrogen content. These cultures were inoculated with two distinct strains (CECT 11045 and B11), previously grown and adapted in two different pre-inoculum media. The culture medium containing trehalose, yeast extract, MgSO4, KH2PO3 and vitamins, allowed for the best development of the two strains.