scholarly journals Production of Biocellulosic Ethanol from Wheat Straw

10.14311/1542 ◽  
2012 ◽  
Vol 52 (3) ◽  
Author(s):  
W. Ali Ismail ◽  
R. Rasul Braim ◽  
K. Aziz Ketuly ◽  
D. Siti Shamsiah Awang Bujag ◽  
Zainudin Arifin
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Acid Hydrolysis ◽  
Wheat Straw ◽  
Ethanol Concentration ◽  
Fermentation Inhibitors ◽  
Two Stage ◽  
Fermentation Efficiency ◽  
Lignocellulosic Feedstock ◽  
The World ◽  
Ethanol Yields

Wheat straw is an abundant lignocellulosic feedstock in many parts of the world, and has been selected for producing ethanol in an economically feasible manner. It contains a mixture of sugars (hexoses and pentoses).Two-stage acid hydrolysis was carried out with concentrates of perchloric acid, using wheat straw. The hydrolysate was concentrated by vacuum evaporation to increase the concentration of fermentable sugars, and was detoxified by over-liming to decrease the concentration of fermentation inhibitors. After two-stage acid hydrolysis, the sugars and the inhibitors were measured. The ethanol yields obtained from by converting hexoses and pentoses in the hydrolysate with the co-culture of Saccharomyces cerevisiae and Pichia stipites were higher than the ethanol yields produced with a monoculture of S. cerevisiae. Various conditions for hysdrolysis and fermentation were investigated. The ethanol concentration was 11.42 g/l in 42 h of incubation, with a yield of 0.475 g/g, productivity of 0.272 gl ·h, and fermentation efficiency of 92.955 %, using a co-culture of Saccharomyces cerevisiae and Pichia stipites

Detoxification of Wheat Straw Formic Acid Hydrolysis and Xylitol Production

2011 ◽  
Vol 383-390 ◽  
pp. 5453-5457 ◽  
Author(s):  
Jun Ping Zhuang ◽  
Lu Lin ◽  
Sun Yong ◽  
Chun Sheng Pang
Keyword(s):  
Ion Exchange ◽  
Formic Acid ◽  
Acid Hydrolysis ◽  
Wheat Straw ◽  
Exchange Resin ◽  
Reaction System ◽  
Ion Exchange Resin ◽  
Fermentation Inhibitors ◽  
Formic Acid Hydrolysis ◽  
Wheat Straw Hydrolysate

Xylitol can be obtained from hemicelullosic fraction of lignocellulosic materials containing D-xylose. Formic acid hydrolysis is widely used in lignocellulose pretreatment. However, formic acid hydrolysis wheat straw cannot be directly used as fermentation subsequently owing to various fermentation inhibitors, especially the formic acid in reaction system and released during pretreatment. This study describes main hydrolysis components and inhibitors prepared by hydrolysis of wheat straw with formic acid solution, and different detoxification methods ware used to romve the inhibitors. Study found treatment of wheat straw hydrolysate with overliming treatment and D311 ion-exchange resin had a good result on reduction formic acid and other main inhibitors, results showed which can eliminate 94% of residual formic acid and with only 15% reducion of xylose. To verify the effectiveness of different detoxification methods, hydrolysates of detoxification werr fermented by Candida.tropicalis AS2.1776, and the results also found that the hydrolysate treatmented with overliming treatment and D311 ion-exchange resin have the hightest xylitol yield.

scholarly journals Ethanolic Fermentation Efficiency of Seaweed Solid Waste hydrolysates by Saccharomyces cerevisiae

2016 ◽  
Vol 11 (1) ◽  
pp. 7
Author(s):  
Pujoyuwono Martosuyono
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Solid Waste ◽  
Ethanol Yield ◽  
Conversion Ratio ◽  
Ethanolic Fermentation ◽  
Fermentation Efficiency ◽  
Theoretical Yield ◽  
Acid And Base ◽  
Ethanol Yields ◽  
Saccharification Yield

The objective of this research are to determine the Saccharification and fermentation efficiency of seaweed solid waste hydrolysate by S. cerevisiae in anaerobic condition. The optimum saccharification yield of acid pretreated waste (40.93+1.72%) was obtained after 48 h with a saccharification rate of 0.51±0.02 g/L/h. Higher yield was showed by NaOH pretreated waste (67.29+1.24%) at 24 hours with a saccharification rate of 0.81±0.06 g/L/h. . Fermentation of enzymatic hydrolysates of acid and base pretreated samples with S. cerevisiae produced maximum ethanol 7.52±0.24 g/L and 14.5+0.54 g/L respectively after 72 hours fermentation. Maximum ethanol yield of 0.31±0.03 g/g and 0.40+0.02 g/g sugar respectively for acid and base pretreated samples. The ethanol yields showing that base pretreated sample was producing higher conversion ratio of substrate (80% of theoretical yield) compared to acid pretreated sample (62% of theoretical yield).  

Dilute Acid Hydrolysis of Wheat Straw Oligosaccharides

2008 ◽  
Vol 153 (1-3) ◽  
pp. 116-126 ◽  
Author(s):  
Luís C. Duarte ◽  
Talita Silva-Fernandes ◽  
Florbela Carvalheiro ◽  
Francisco M. Gírio
Keyword(s):  
Acid Hydrolysis ◽  
Wheat Straw ◽  
Dilute Acid ◽  
Dilute Acid Hydrolysis ◽  
Hydrolysis Of

scholarly journals Optimized acid hydrolysis of the polysaccharides from the seaweed Solieria filiformis (Kützing) P.W. Gabrielson for bioethanol production

2017 ◽  
Vol 39 (4) ◽  
pp. 423 ◽  
Author(s):  
George Meredite Cunha de Castro ◽  
Norma Maria Barros Benevides ◽  
Maulori Curié Cabral ◽  
Rafael De Souza Miranda ◽  
Enéas Gomes Filho ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Sulfuric Acid ◽  
Acid Hydrolysis ◽  
Kinetic Parameters ◽  
Renewable Resource ◽  
Bioethanol Production ◽  
Seaweed Species ◽  
Mild Conditions ◽  
Hydrolysis Of ◽  
Solieria Filiformis

 The seaweeds are bio-resource rich in sulfated and neutral polysaccharides. The tropical seaweed species used in this study (Solieria filiformis), after dried, shows 65.8% (w/w) carbohydrate, 9.6% (w/w) protein, 1.7% (w/w) lipid, 7.0% (w/w) moisture and 15.9% (w/w) ash. The dried seaweed was easily hydrolyzed under mild conditions (0.5 M sulfuric acid, 20 min.), generating fermentable monosaccharides with a maximum hydrolysis efficiency of 63.21%. Galactose and glucose present in the hydrolyzed were simultaneously fermented by Saccharomyces cerevisiae when the yeast was acclimated to galactose and cultivated in broth containing only galactose. The kinetic parameters of the fermentation of the seaweed hydrolyzed were Y(P⁄S) = 0.48 ± 0.02 g.g−1, PP = 0.27 ± 0.04 g.L−1.h−1, h = 94.1%, representing a 41% increase in bioethanol productivity. Therefore, S. filiformis was a promising renewable resource of polysaccharides easily hydrolyzed, generating a broth rich in fermentable monosaccharides for ethanol production. 

scholarly journals Two-stage, dilute sulfuric acid hydrolysis of wood : an investigation of fundamentals

1985 ◽  
Author(s):  
John F. Harris ◽  
Andrew J. Baker ◽  
Anthony H. Conner ◽  
Thomas W. Jeffries ◽  
James L. Minor ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Acid Hydrolysis ◽  
Two Stage ◽  
Dilute Sulfuric Acid ◽  
Hydrolysis Of

Acid hydrolysis of wheat straw: A kinetic study

2012 ◽  
Vol 36 ◽  
pp. 346-355 ◽  
Author(s):  
Esther Guerra-Rodríguez ◽  
Oscar M. Portilla-Rivera ◽  
Lorenzo Jarquín-Enríquez ◽  
Jose A. Ramírez ◽  
Manuel Vázquez
Keyword(s):  
Kinetic Study ◽  
Acid Hydrolysis ◽  
Wheat Straw ◽  
Hydrolysis Of

scholarly journals Novel Approach in the Construction of Bioethanol-Producing Saccharomyces cerevisiae Hybrids

2019 ◽  
Vol 57 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Anamarija Štafa ◽  
Andrea Pranklin ◽  
Ivan Krešimir Svetec ◽  
Božidar Šantek ◽  
Marina Svetec Miklenić ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Gene Targeting ◽  
Co2 Production ◽  
Production Test ◽  
Fermentation Inhibitors ◽  
Lignocellulosic Hydrolysates ◽  
Novel Approach ◽  
Ethanol Producer ◽  
High Ethanol ◽  
Selection Of

Bioethanol production from lignocellulosic hydrolysates requires a producer strain that tolerates both the presence of growth and fermentation inhibitors and high ethanol concentrations. Therefore, we constructed heterozygous intraspecies hybrid diploids of Saccharomyces cerevisiae by crossing two natural S. cerevisiae isolates, YIIc17_E5 and UWOPS87-2421, a good ethanol producer found in wine and a strain from the flower of the cactus Opuntia megacantha resistant to inhibitors found in lignocellulosic hydrolysates, respectively. Hybrids grew faster than parental strains in the absence and in the presence of acetic and levulinic acids and 2-furaldehyde, inhibitors frequently found in lignocellulosic hydrolysates, and the overexpression of YAP1 gene increased their survival. Furthermore, although originating from the same parental strains, hybrids displayed different fermentative potential in a CO2 production test, suggesting genetic variability that could be used for further selection of desirable traits. Therefore, our results suggest that the construction of intraspecies hybrids coupled with the use of genetic engineering techniques is a promising approach for improvement or development of new biotechnologically relevant strains of S. cerevisiae. Moreover, it was found that the success of gene targeting (gene targeting fidelity) in natural S. cerevisiae isolates (YIIc17_E5α and UWOPS87-2421α) was strikingly lower than in laboratory strains and the most frequent off-targeting event was targeted chromosome duplication.

Null mutation of NRG1 gene improves tolerance of Saccharomyces cerevisiae to fermentation inhibitors

2016 ◽  
Vol 33 ◽  
pp. S91-S92
Author(s):  
Eun-Hee Park ◽  
Chan-Yeong Choi ◽  
Yun-Ji Cho ◽  
Myoung-Dong Kim
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Null Mutation ◽  
Fermentation Inhibitors

scholarly journals Ethanol Production from Nondetoxified Dilute-Acid Lignocellulosic Hydrolysate by Cocultures of Saccharomyces cerevisiae Y5 and Pichia stipitis CBS6054

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Ping Wan ◽  
Dongmei Zhai ◽  
Zhen Wang ◽  
Xiushan Yang ◽  
Shen Tian
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Ethanol Production ◽  
Ethanol Concentration ◽  
Ethanol Yield ◽  
Synthetic Medium ◽  
Pichia Stipitis ◽  
Dilute Acid ◽  
Acid Hydrolysate ◽  
Issatchenkia Orientalis ◽  
Final Ethanol Concentration

Saccharomyces cerevisiae Y5 (CGMCC no. 2660) and Issatchenkia orientalis Y4 (CGMCC no. 2159) were combined individually with Pichia stipitis CBS6054 to establish the cocultures of Y5 + CBS6054 and Y4 + CBS6054. The coculture Y5 + CBS6054 effectively metabolized furfural and HMF and converted xylose and glucose mixture to ethanol with ethanol concentration of 16.6 g/L and ethanol yield of 0.46 g ethanol/g sugar, corresponding to 91.2% of the maximal theoretical value in synthetic medium. Accordingly, the nondetoxified dilute-acid hydrolysate was used to produce ethanol by co-culture Y5 + CBS6054. The co-culture consumed glucose along with furfural and HMF completely in 12 h, and all xylose within 96 h, resulting in a final ethanol concentration of 27.4 g/L and ethanol yield of 0.43 g ethanol/g sugar, corresponding to 85.1% of the maximal theoretical value. The results indicated that the co-culture of Y5 + CBS6054 was a satisfying combination for ethanol production from non-detoxified dilute-acid lignocellulosic hydrolysates. This co-culture showed a promising prospect for industrial application.

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