The use of dried spent yeast as a low-cost nitrogen supplement in ethanol fermentation from sweet sorghum juice under very high gravity conditions
Document title: The use of dried spent yeast as a low-cost nitrogen supplement in ethanol fermentation from sweet sorghum juice under very high gravity conditions
Journal: Electronic journal of biotechnology
Database: PERIÓDICA
System number: 000359572
ISSN: 0717-3458
Authors: 1
2
3
2
Institutions: 1Khon Kaen University, Graduate School, Khon Kaen. Tailandia
2Khon Kaen University, Faculty of Technology, Khon Kaen. Tailandia
3Khon Kaen University, Faculty of Agriculture, Khon Kaen. Tailandia
Year:
Volumen: 14
Number: 6
Pages: 3-3
Country: Chile
Language: Inglés
Document type: Artículo
Approach: Experimental
English abstract Dried spent yeast (DSY) was used as a low-cost nitrogen supplement for ethanol fermentation from sweet sorghum juice under very high gravity (VHG) conditions by Saccharomyces cerevisiae NP 01. The fermentation was carried out at 30ºC in a 5-litre bioreactor. The results showed that DSY promoted ethanol production efficiencies. The ethanol concentration (P), productivity (Qp) and yield (Yp/s) of the sterile juice (total sugar of 280 g l-1) supplemented with 8 g l-1 of DSY were not different from those supplemented with yeast extract and/or peptone at the same amount. The initial yeast cell concentration of 5 x 107 cells ml-1 was found to be optimal for scale-up ethanol production. In addition, an increase in sugar concentration in inoculum preparation medium (from 10 to 100 g l-1) improved the ability of the inoculum to produce ethanol under the VHG conditions. When S. cerevisiae NP 01 grown in the juice containing 100 g l-1 of total sugar was used as the inoculum for ethanol fermentation, the P, Qp and Yp/s obtained were 108.98 ± 1.16 g l-1, 2.27 ± 0.06 g l-1 h-1 and 0.47 ± 0.01 g g-1, respectively. Similar results were also observed when the ethanol fermentation was scaled up to a 50-litre bioreactor under the same conditions. The cost of the sweet sorghum for ethanol production was US$ 0.63 per litre of ethanol. These results clearly indicate the high potential of using sweet sorghum juice supplemented with DSY under VHG fermentation for ethanol production in industrial applications
Disciplines: Química
Keyword: Bioquímica,
Fermentaciones,
Química industrial,
Bioetanol,
Levadura seca,
Ampliación,
Jugo de sorgo dulce,
Fermentación de alta gravedad,
Biotecnología
Keyword: Chemistry,
Biochemistry,
Fermentation,
Industrial chemistry,
Bioethanol,
Dried yeast,
Scale up,
Sweet sorghum juice,
High gravity fermentation,
Biotechnology
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