|
Publication
|
Research Title |
Preliminary study of kinetics and mathematical models of batch ethanol fermentation from sweet sorghum stem juice by Saccharomyces cerevisiae immobilized on sweet sorghum stalks. |
Date of Distribution |
16 September 2012 |
Conference |
Title of the Conference |
15th International Biotehcnology Symposium and Exhibition |
Organiser |
The Korean society for biotechnology and bioengineering |
Conference Place |
EXCO |
Province/State |
Deagu, Republic of Korea |
Conference Date |
16 September 2012 |
To |
21 September 2012 |
Proceeding Paper |
Volume |
15 |
Issue |
1 |
Page |
166 |
Editors/edition/publisher |
|
Abstract |
Kinetics and mathematical models for batch ethanol fermentation from sweet sorghum stem juice by Saccharomyces cerevisiae NP 01 immobilized on sweet sorghum stalks were developed. The models accounted for substrate limitation, substrate inhibition, ethanol inhibition and cell death. Immobilized yeast cells in the sweet sorghum stalk pieces (6 × 6 × 6 to 20 × 20 × 20 mm3) were inoculated into sterile juice in 500-ml air-locked flasks. The ratio of the carriers to sterile juice was 30% w/v. Specific growth rates (µ) of total viable cells (immobilized and freely suspended cells) at the different initial sugar concentrations ranging from 120 – 280 g l-1 were calculated. The results showed that µ increased with increasing in the initial sugar concentrations up to 240 g l-1 with the values of 0.2188 to 0.2783 h-1, while µ was 0.2186 h-1 at 280 g l-1 of total sugar indicating that substrate inhibition occurred at this sugar concentration. The µ values at 120 – 240 g l-1 of sugar concentration were used to evaluate µmax and KS by Lineweaver–Burk plot on Monod’s equation. The µmax and KS obtained were 0.3128 h-1 and 47.51 g l-1, respectively. Batch ethanol fermentation from sweet sorghum stem juice containing total sugar concentration of 240 g l-1 by the yeast immobilized on the sweet sorghum stalks was carried out to evaluate other model parameters by non-linear least squares method of Marquardt. The model parameters obtained were substrate inhibition constant for growth (KIS), 290.10 g l-1; maximum ethanol concentration for growth (PXmax), 90.63 g l-1; specific production rate (qP), 4.22 g g-1 h-1; substrate limitation constant for ethanol production (KSP), 20.06 g l-1; substrate inhibition constant for ethanol production (KIP), 300.01 g l-1; maximum ethanol concentration for ethanol production (PPmax), 131.84 g l-1; biomass yield (YX/S), 1.62 g g-1; specific death rate (Kd), 0.00095 h-1 and maintenance energy (m), 0.001 h-1 and the mathematical models for biomass production, substrate consumption and ethanol formation were developed by modified Monod’s equation. The results indicated that the three models could be used to describe the dynamics of biomass, substrate and ethanol concentrations of ethanol fermentation from sweet sorghum stem juice by the yeast immobilized on sweet sorghum stalks with high accuracy (R2 = 0.9220, 0.9966 and 0.9955, respectively). |
Author |
|
Peer Review Status |
มีผู้ประเมินอิสระ |
Level of Conference |
นานาชาติ |
Type of Proceeding |
Abstract |
Type of Presentation |
Poster |
Part of thesis |
true |
Presentation awarding |
false |
Attach file |
|
Citation |
0
|
|
|
|
|
|
|