Bioethanol production by yeasts isolated From sugar cane molasses

Abstract

Introduction. The use of ethanol as a biofuel offers a wide range of promising alternatives which includes the decrease in negative impact on the environmental and the possibility of safe energy. Objective. To isolate highest bioethanol producer yeasts from sugar cane molasses. Materials and methods. Yeast strains were iso- lated from sugar cane molasses samples obtained from differents sugar factories in Tucumán using YPD and YPS solid mediums with antibiotics. Fermentations assays were carried out in glass flasks with 200 mL of YPS medium with 250 g/L of sucrose and were incubated at 30ºC. Residual sugars, biomass and ethanol con- centrations were determined. Results and Discussion. Three iso- lated yeasts with a hight fermentative power were evaluated: A2, A10 and A11, which produced 11.74, 14.09 and 13.55% of ethanol respectively. A10 strain was selected for further studies because the highest ethanol concentration as well as specific productivity values were obtained with this strain.