Dutra E.D.,Federal University of Pernambuco |
Neto A.G.B.,Genetech Research |
de Souza R.B.,Laboratory of Bioprocessing |
de Souza R.B.,Genetech Research |
And 5 more authors.
Sugar Tech | Year: 2013
The decline in the use of fossil fuels in the future is due to the gradual depletion of their reserves and related environmental issues. Biofuels including ethanol are presented as a renewable alternative to fossil fuels. However, ethanol production, generally from sugarcane demands the use of agricultural land and other natural resources, with emphasis on water and other nutrients. Sorghum is tolerant to drought. The purpose of this study was to evaluate the potentiality of eight sweet sorghum cultivars in order to expand the ethanol production to areas with limited supply of water, not suitable for sugarcane which requires irrigation. The cultivars developed by breeding programs in the state of Pernambuco, Brazil, were analyzed for fermentation by industrial strain of Saccharomyces cerevisiae, at 33 °C, under static conditions for a period of 6 h. All assessed parameters showed some statistically significant differences among cultivars (p < 0.01), especially ethanol concentration (P) and the volumetric productivities (Qp) in the following order: Willey (P = 64.77 ± 4.4 g L-1 and Qp = 10.79 ± 0.74 g L-1 h-1), Wray (P = 59.10 ± 1.7 g L-1 and Qp = 9.85 ± 0.28 g L-1 h-1), BR 506 (P = 59.07 ± 1.3 g L-1 and Qp = 9.84 ± 0.21 g L-1 h-1) and SF 15 (54.40 ± 0.4 g L-1 and Qp = 9.07 ± 0.06 g L-1 h-1). The highest potentials for ethanol yield per hectare were observed for the cultivars SF 15 (3142.51 ± 428.47 L ha-1) and BR 506 (2193.95 ± 383.58 L ha-1). Therefore, the cultivars SF 15 and BR 506 seem to be very promising as an energy crop to be produced in areas with environmental conditions similar to Pernambuco. © 2013 Society for Sugar Research & Promotion.
De Souza R.B.,Federal University of Pernambuco |
De Souza R.B.,Laboratory of Bioprocessing |
Santos B.M.D.,Federal University of Pernambuco |
De Fatima Rodrigues De Souza R.,Federal University of Pernambuco |
And 6 more authors.
Journal of Industrial Microbiology and Biotechnology | Year: 2012
This work describes the effects of the presence of the yeast Dekkera bruxellensis and the bacterium Lactobacillus vini on the industrial production of ethanol from sugarcane fermentation. Both contaminants were quantified in industrial samples, and their presence was correlated to a decrease in ethanol concentration and accumulation of sugar. Then, laboratory mixed-cell fermentations were carried out to evaluate the effects of these presumed contaminants on the viability of Saccharomyces cerevisiae and the overall ethanol yield. The results showed that high residual sugar seemed the most significant factor arising from the presence of D. bruxellensis in the industrial process when compared to pure S. cerevisiae cultures. Moreover, when L. vini was added to S. cerevisiae cultures it did not appear to affect the yeast cells by any kind of antagonistic effect under stable fermentations. In addition, when L. vini was added to D. bruxellensis cultures, it showed signs of being able to stimulate the fermentative activity of the yeast cells in a way that led to an increase in the ethanol yield.. © Society for Industrial Microbiology and Biotechnology 2012.