Predictive modelling of growth and enzymatic synthesis and activity by a cocktail of Yarrowia lipolytica, Zygosaccharomyces bailii and Pichia anomala Original Research Article

The aims of the investigations are the development and combination of predictive models for growth (increase in cellular number) and lipase synthesis and protease activity by a cocktail of yeast species comprising Yarrowia lipolytica, Zygosaccharomyces bailii and Pichia anomala. Determinations of yeast number and enzyme synthesis and activity were made within the three-dimensional matrix of environmental conditions incorporating temperatures between 2°C and 20°C, pH values between 4.0 and 7.5 and water activity (aw) between 0.95 and 0.995. The microbiological data produced a reliable model, but it was not possible to use the curve-fitting function to fit the enzymatic data, since most enzyme synthesis and activity takes place during the stationary phase of growth. A predictive generic model for growth of yeasts is published and a database of systematic information describing enzyme synthesis and activity within the matrix of environmental conditions investigated will be made available.