Nutritional requirements of Brettanomyces bruxellensis: Growth and physiology in batch and chemostat cultures

The nutritional requirements of Brettanomyces bruxellensis have been invest igated. Batch culture and chemostat pulse techniques were used to identify growth-limiting nutrients. The study included determination of the essentia l components of the culture medium and quantification of the effects of the components. Among the components tested, ammonium sulfate and yeast extrac t had a significant effect on glucose consumption, growth, and ethanol prod uction. However, if the ammonium sulfate concentration is above 2 g/L, an i nhibitory effect on B. bruxellensis growth is observed. The yeast extract a ppears to be the most important and significant component for growth. The m aximum amount of synthesized biomass is proportional to the concentration o f yeast extract added to the culture broth (in the tested range). Magnesium and phosphate ions are probably not essential for B. bruxellensis. These i ons appear to be supplied in sufficient amounts by the yeast extract in the culture medium. Brettanomyces bruxellensis appears to have very low nutrit ional requirements for growth.