INVESTIGADORES
RODRIGUEZ maria eugenia
congresos y reuniones científicas
Título:
Characterization of native Saccharomyces cerevisiae strains for bioethanol production.
Autor/es:
ORIGONE A.; DAVILA E.; RAMACHARY A. ; KAMINI N. ; LOPES C.A.; RODRÍGUEZ M.E
Reunión:
Simposio; 34th International Specialised Symposium on Yeast; 2018
Resumen:
The production of bioethanol based on the fermentation of sugar from renewablesources is a friendly environmental alternative that promotes reducing the consumptionof fossil fuels. Saccharomyces cerevisiae is a yeast widely used in fermentationprocesses, it has proved to be more robust than bacteria, being more tolerant to ethanoland inhibitors present in hydrolysates of lignocellulosic materials. The fruticulture, themain economic activity of Río Negro and Neuquén provinces (North Patagonia),produces abundant raw material wastes rich in lignocellulose and sugar that could beutilized for bioethanol production. The aim was to study the behavior of S. cerevisiaestrains from different origins under stress conditions encountered during theproduction of bioethanol. In a first step, the ethanol tolerance of sixty S. cerevisiaestrains from wine (Argentina), apple chicha (Chile) and Toddy (India) was analyzed inmicroplates assays containing 0-15% (v/v) ethanol. OD data were fitted to Gompertzmodel and kinetic parameters (both μmax and lag) were calculated. All strains grew until12% (v/v) of ethanol. Twelve strains -3 from each origin- showing the shortest lag valueand the highest μmax (media values: 11.83 ± 0.89 h and 0.15 ± 0.01 h-1, respectively)were then evaluated in their ability to grow in different stress conditions includingtemperature (25ºC-45°C), pH (2 to 5), glucose (2 to 300 g/L), Na2SO4 (0 to 50 g/L) andacetic acid (0 to 8 g/L) concentrations. As a general rule, all the strains grew at pH 3, 4and 5, and at temperatures below 40°C. Glucose and Na2SO4 concentrations did notaffect the growth of strains. Conversely, concentrations of acetic acid higher than 3 g/Lnegatively affected the development of the yeasts. The tolerance of selected strains todifferent stress factors make it possible to think about their potential application inbioethanol production using regional industry wastes