Effect of xylose and nutrients concentration on ethanol production by a newly isolated extreme thermophilic bacterium

2011 ◽  
Vol 64 (2) ◽  
pp. 341-347 ◽  
Author(s):  
Ana F. Tomas ◽  
Dimitar Karakashev ◽  
Irini Angelidaki
Keyword(s):  
Production Process ◽  
Ethanol Production ◽  
Yeast Extract ◽  
Ethanol Yield ◽  
Thermophilic Bacterium ◽  
Promising Candidate ◽  
Theoretical Yield ◽  
Ethanol Yields ◽  
Nutrients Concentration ◽  
Xylose Concentration

An extreme thermophilic ethanol-producing strain was isolated from an ethanol high-yielding mixed culture, originally isolated from a hydrogen producing reactor operated at 70 °C. Ethanol yields were assessed with increasing concentrations of xylose, up to 20 g/l. The ability of the strain to grow without nutrient addition (yeast extract, peptone and vitamins) was also assessed. The maximum ethanol yield achieved was 1.28 molethanol/molxylose consumed (77% of the theoretical yield), at 2 g/l of initial xylose concentration. The isolate was able to grow and produce ethanol as the main fermentation product under most of the conditions tested, including in media lacking vitamins, peptone and yeast extract. The results indicate that this new organism is a promising candidate for the development of a second generation bio-ethanol production process.

scholarly journals POTENCIAL DE CLONES EXPERIMENTAIS DE BATATA-DOCE PARA PRODUÇÃO DE ETANOL

Nativa ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 352
Author(s):  
Adriano Mendes Lourenço ◽  
Aline Torquato Tavares ◽  
Tiago Alves Ferreira ◽  
Danilo Alves da Silva Porto Lopes ◽  
João Victor Gonçalves Carline ◽  
...  
Keyword(s):  
Ethanol Production ◽  
Sweet Potato ◽  
Ipomoea Batatas ◽  
Ethanol Yield ◽  
Starch Content ◽  
Great Ability ◽  
Ethanol Yields ◽  
Root Starch ◽  
Breeding Selection ◽  
Starch Yield

A batata-doce (Ipomoea batatas (L.) Lam.) tem sido reportada como uma das espécies de planta com grande capacidade de converter biomassa em matéria prima para produção de etanol. O objetivo do trabalho foi avaliar o potencial de clones de batata-doce para produção de etanol. Foram avaliados 60 clones de batata-doce para produtividade de raízes, teor de amido nas raízes, produtividade de amido, coloração da casca e da polpa e o rendimento de etanol. O clone BDTO#122,32 e as cultivares Ana Clara e Carolina Vitória com média de 46,77; 42,75 e 41,25 t ha-¹, respectivamente, foram os que mais conseguiram acumular biomassa na forma de raiz. Os clones que apresentam as maiores médias de produtividade de amido por hectare foram BDTO#144.22 e BDTO#100.23, com valores de 15,46 e 14,16% t ha-1, com rendimentos de etanol de 8,33 e 7,63 m³ ha-¹. Os clones BDTO#144.22 e BDTO#100.23 apresentaram as maiores médias de produtividade de amido por hectare e rendimento de etanol, sendo, portanto, os mais promissores para a produção de etanol.Palavras-chave: Ipomoea batatas (L.) Lam, melhoramento genético, seleção, biocombustível. POTENTIAL OF EXPERIMENTAL CLONES OF SWEET POTATO FOR ETHANOL PRODUCTION ABSTRACT:Sweet potato (Ipomoea batatas (L.) Lam.) Has been reported as one of the plant species with great ability to convert biomass into feedstock for ethanol production. The objective of this work was to evaluate the potential of sweet potato clones for ethanol production. Twenty-six sweet potato clones were evaluated for root productivity, root starch content, starch yield, bark and pulp color, and ethanol yield. Clone BDTO # 122.32 and cultivars Ana Clara and Carolina Vitória averaging 46.77; 42.75 and 41.25 t ha-1, respectively, were the ones that were able to accumulate biomass in the root form. The clones presenting the highest starch productivity per hectare were BDTO # 144.22 and BDTO # 100.23, with values of 15.46 and 14.16% t ha-1, with ethanol yields of 8.33 and 7.63 m³ ha-¹. The clones BDTO # 144.22 and BDTO # 100.23 showed the highest averages of starch productivity per hectare and yield of ethanol, thus being the most promising for the production of ethanol.Keywords: Ipomoea potatoes (L.) Lam, breeding, selection, biofuel.

scholarly journals Bioconversion process of source-separated organic waste for ethanol production

2021 ◽  
Author(s):  
Valeriy Bekmuradov
Keyword(s):  
Kinetic Model ◽  
Ethanol Production ◽  
Lignocellulosic Biomass ◽  
Substrate Concentration ◽  
Ethanol Yield ◽  
Ethanol Conversion ◽  
Ethanol Yields ◽  
Environmental Goals ◽  
Ethanol Washing ◽  
Experimental Values

Production of biofuel such as ethanol from lignocellulosic biomass is a beneficial way to meet sustainability, energy security, and environmental goals. Lignocellulosic biomass such as source-separated organic (SSO) waste is particularly attractive since it is widely available, often at a negative cost, reduce the land depletion from using food-based biomass for ethanol production and reduce the amount of generated waste. Therefore, in order to meet the future fuel demands and cope with increasing volume of municipal waste this study was a first attempt to use SSO as a feedstock for ethanol production. The main objectives of the study were: a) to compare standard and modified celluloseorganic- solvent-based lignocellulosic fractionation (COSLIF) pretreatment of SSO waste for ethanol production in terms of enzyme savings, sugar formation and ethanol yields; b) to produce ethanol from SSO by using modified COSLIF pretreatment and fermentation with two different recombinant strains: Z. mobilis 8b and S. cerevisiae DA2416; and c) to develop experimental kinetic model capable of predicting behavior of batch SSCF on SSO waste with different SSO substrate concentrations using Berkeley Madonna program. Based on the obtained results, it was found that SSO is an excellent feedstock material for ethanol conversion. The efficiency of modified COSLIF pretreatment was improved by 20% compared to standard method using ethanol washing of pretreated SSO samples during the experimental procedures instead of acetone. On average, glucose yield from SSO samples pretreated by modified COSLIF was about 90% compared to 10% for untreated samples. S. cerevisiae DA2416 outperformed Z. mobilis 8b on ethanol yields during the fermentation process, with 0.50 g ethanol/g potential sugar fed on SSO in less than 5 days, with a 96% cellulose conversion, totalling in 150 g/L ethanol produced. A kinetic model with newly integrated values of experimentally defined SSO feedstock constants was proven to predict the ethanol yield accurately with substrate concentration ranges of 20 g/L - 50 g/L. Model prediction at higher substrate concentration (e.g. 100 g/L) deviated from the experimental values, suggesting that ethanol inhibition is a major factor in bioethanol conversion.

Changes in ethanol production potential due to species, cultivar and location on the Canadian prairie

2010 ◽  
Vol 90 (2) ◽  
pp. 163-171 ◽  
Author(s):  
J G McLeod ◽  
W E May ◽  
D F Salmon ◽  
K. Sosulski ◽  
J B Thomas ◽  
...  
Keyword(s):  
Ethanol Production ◽  
Ethanol Yield ◽  
Starch Content ◽  
Species Selection ◽  
Western Canada ◽  
Canadian Prairie ◽  
Spring Triticale ◽  
Ethanol Yields ◽  
Small Grains ◽  
Selection Of

In recent years there has been a rapid growth in the fuel ethanol industry, increasing the need for a consistent supply of feedstock. This study was conducted to evaluate the potential of small grains in western Canada to supply feedstock to the ethanol industry. Thirty-one lines and cultivars of Canadian small grains were evaluated: eleven cultivars comprising five classes spring wheat, six cultivars of two and six row barley of feed, malting and hulless classes, eight cultivars of spring triticale and six cultivars of oat were grown at seven locations in western Canada and evaluated as feedstock for ethanol production. Starch concentrations and, for certain grains, β-glucan and pentosans were determined and used to estimate ethanol yields in L t-1 and L ha-1. On average, ethanol yield in L t-1 was wheat > triticale > barley > oat; however, for yield in L ha-1, only oat was inferior. This ranking was consistent across all locations tested. Estimates of ethanol yields indicated that certain cultivars within classes of grains were superior, such as CDC Buck, SWS 109, HY 617 and Pronghorn in the hulless barley, CWSWS, CPS-R and Triticale classes, respectively. Locations that produced the highest level of ethanol in one species tended to produce grain with the highest ethanol yields in the other species. Selection of cultivars with greater starch content, different starch quality and reduced pentosans as well as the advancements in and adoption of new fermentation technologies may lead to greater estimates of ethanol yields of small grain cereals in the future.Key words: Cereal grains, starch, pentosans, β-glucans, ethanol yield

scholarly journals Engineered Polyploid Yeast Strains Enable Efficient Xylose Utilization and Ethanol Production in Corn Hydrolysates

2021 ◽  
Vol 9 ◽  
Author(s):  
Lulu Liu ◽  
Mingjie Jin ◽  
Mingtao Huang ◽  
Yixuan Zhu ◽  
Wenjie Yuan ◽  
...  
Keyword(s):  
Ethanol Production ◽  
Comprehensive Evaluation ◽  
Ethanol Yield ◽  
Xylose Utilization ◽  
Acid Pretreatment ◽  
Experimental Conditions ◽  
Total Sugars ◽  
Yeast Strains ◽  
Ethanol Yields ◽  
Substrate Concentrations

The reported haploid Saccharomyces cerevisiae strain F106 can utilize xylose for ethanol production. After a series of XR and/or XDH mutations were introduced into F106, the XR-K270R mutant was found to outperform others. The corresponding haploid, diploid, and triploid strains were then constructed and their fermentation performance was compared. Strains F106-KR and the diploid produced an ethanol yield of 0.45 and 0.48 g/g total sugars, respectively, in simulated corn hydrolysates within 36 h. Using non-detoxicated corncob hydrolysate as the substrate, the ethanol yield with the triploid was approximately sevenfold than that of the diploid at 40°C. After a comprehensive evaluation of growth on corn stover hydrolysates pretreated with diluted acid or alkali and different substrate concentrations, ethanol yields of the triploid strain were consistently higher than those of the diploid using acid-pretreatment. These results demonstrate that the yeast chromosomal copy number is positively correlated with increased ethanol production under our experimental conditions.

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).  

scholarly journals High yield of ethanol production by the strain Fusarium sp. ZW-21 with corncob hydrolysate

BioResources ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 622-632
Author(s):  
Xiaohui Liang ◽  
Hongyu Si ◽  
Dongliang Hua ◽  
Yuxiao Zhao
Keyword(s):  
Ethanol Production ◽  
Yeast Extract ◽  
Incubation Temperature ◽  
Ethanol Yield ◽  
Inoculum Size ◽  
Effect Of Temperature ◽  
High Yield ◽  
Polysorbate 80 ◽  
Corncob Hydrolysate ◽  
Fusarium Sp

The filamentous fungus strain Fusarium sp. ZW-21 was used for ethanol production with corncob hydrolysate. The fermentation conditions of ethanol production from corncob hydrolysate by the strain were investigated, and the effect of temperature, pH, nitrogen source, and surfactants on the ethanol production was investigated. The two factors yeast extract and polysorbate 80 were selected for further optimization by response surface methodology. The optimal conditions for ethanol production by the strain Fusarium sp. ZW-21 were 50 g/L sugar of corncob hydrolysate, 10.35 g/L yeast extract, 10 g/L KH2PO4, 0.5 g/L MgSO4·7H2O, 0.38 g/L polysorbate 80, pH 6.0, inoculum size of 1 mL/50 mL medium, and incubation temperature of 30 °C. The fermentation period was 5 d under oxygen-limited conditions, and the ethanol yield was 24.2 g/L.

Construction and Evaluation of Recombinant Strains for Ethanol Production from Lignocellulosic Hydrolysate

2011 ◽  
Vol 347-353 ◽  
pp. 48-51 ◽  
Author(s):  
Shao Lan Zou ◽  
Chao Zhang ◽  
Yuan Yuan Ma ◽  
Le You ◽  
Min Hua Zhang
Keyword(s):  
Carbon Source ◽  
Ethanol Production ◽  
Rapid Growth ◽  
Sole Carbon Source ◽  
Ethanol Concentration ◽  
Ethanol Yield ◽  
Corn Straw ◽  
Lignocellulosic Hydrolysate ◽  
Preliminary Results ◽  
Theoretical Yield

The recombinant Z.mobilis CX was constructed. Its ethanol concentration and ethanol yield from 2% xylose at 36 h were 6.73 g/L and 82.3% of theoretical yield, respectively. The recombinant S.cerevisiae YB was constructed and was showed to utilize cellobiose as the sole carbon source for rapid growth and ethanol production. The maximum ethanol concentration 7.493 g/L and ethanol yield 77.4% of theoretical yield from 2% cellobiose were obtained at 24 h. Further, the preliminary results of SSF of pretreated corn straw demonstrated the potential of improving ethanol production and reducing the costs of cellose enzymes used by co-fermentation of CX and YB.

Improvement in Ethanol Yield from Lignocellulo-Starch Biomass using Saccharomyces cerevisiae alone or its Co-culture with Scheffersomyces stipitis

2020 ◽  
Vol 9 (1) ◽  
pp. 57-76
Author(s):  
Madhanamohanan G. Mithra ◽  
Gouri Padmaja
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Ethanol Production ◽  
Ethanol Yield ◽  
Relative Advantage ◽  
Vegetable Crops ◽  
Fed Batch ◽  
Scheffersomyces Stipitis ◽  
Separate Hydrolysis And Fermentation ◽  
Ethanol Yields ◽  
Sugar Levels

Background: Literature on ethanol production from Lignocellulo-Starch Biomass (LCSB) containing starch besides cellulose and hemicellulose, is scanty. Fed-Batch Separate Hydrolysis And Fermentation (F-SHF) was earlier found more beneficial than Fed-Batch Simultaneous Saccharification and Fermentation (F-SSF). Objective: The study aimed at modification of the saccharification and fermentation strategies by including a prehydrolysis step prior to the SSF and compared the ethanol yields with co-culture fermentation using hexose-fermenting Saccharomyces cerevisiae and pentose-fermenting Scheffersomyces stipitis. Methods: Fed-batch hybrid-SSF and Fed-Batch Separate Hydrolysis and Co-culture Fermentation (F-SHCF) in improving ethanol yield from Steam (ST) or Dilute Sulfuric Acid (DSA) pretreated LCSBs (peels of root and vegetable crops) were studied. Results: There was a progressive build-up of ethanol during F-HSSF up to 72h and further production up to 120h was negligible, with no difference among pretreatments. Despite very high ethanol production in the initial 24h of fermentation by S.cerevisiae under F-SHCF, the further increase was negligible. A rapid hike in ethanol production was observed when S. stipitis was also supplemented because of xylose conversion to ethanol. Conclusion: While ST gave higher ethanol (296-323 ml/kg) than DSA under F-HSSF, the latter was advantageous under F-SHCF for certain residues. Prehydrolysis (24h; 50°C) enhanced initial sugar levels favouring fast fermentation and subsequent saccharification and fermentation occurred concurrently at 37°C for 120h, thus leading to energy saving and hence F-HSSF was advantageous. Owing to the low hemicellulose content in LCSBs, the relative advantage of co-culture fermentation over monoculture fermentation was not significant.

Efficient ethanol production from beetle-killed lodgepole pine using SPORL technology and Saccharomyces cerevisiae without detoxification

TAPPI Journal ◽  
2011 ◽  
Vol 10 (5) ◽  
pp. 9-18 ◽  
Author(s):  
J.Y. ZHU ◽  
XIAOLIN LUO ◽  
SHEN TIAN ◽  
ROLLAND GLEISNER ◽  
JOSÉ NEGRÓN ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Ethanol Production ◽  
Cellulosic Ethanol ◽  
Mountain Pine Beetle ◽  
Ethanol Yield ◽  
Lodgepole Pine ◽  
Energy Output ◽  
Pine Beetle ◽  
Ethanol Yields ◽  
Live Tree

This study applied Sulfite Pretreatment to Overcome Recalcitrance of Lignocelluloses (SPORL) to evaluate the potential of mountain pine beetle-killed lodgepole pine for ethanol production using conventional Saccharomyces cerevisiae without hydrolysate detoxification. The results indicate that the beetle-killed trees are more susceptible to SPORL pretreatment than live trees in addition to having enriched glucan and mannan content as reported in the literature. Ethanol yields of 200 and 250 L/metric ton wood were achieved from a live tree and a dead tree (four years after infestation) without process optimization. Ethanol yield of 220 L/metric ton of wood was obtained from a downed tree with more advanced decomposition, which is approximately 10% more than that from a corresponding live tree. Process mass and energy balance analyses suggest that net ethanol energy output (before distillation, lignin energy excluded) from the decomposing tree was approximately 3.2 GJ/metric ton wood, which is 23% more than that from a corresponding live tree. The study demonstrated the robustness of the SPORL process and the utility of beetle-killed trees for cellulosic ethanol production even after many years post mortality.

scholarly journals Bioconversion process of source-separated organic waste for ethanol production

2021 ◽  
Author(s):  
Valeriy Bekmuradov
Keyword(s):  
Kinetic Model ◽  
Ethanol Production ◽  
Lignocellulosic Biomass ◽  
Substrate Concentration ◽  
Ethanol Yield ◽  
Ethanol Conversion ◽  
Ethanol Yields ◽  
Environmental Goals ◽  
Ethanol Washing ◽  
Experimental Values

Production of biofuel such as ethanol from lignocellulosic biomass is a beneficial way to meet sustainability, energy security, and environmental goals. Lignocellulosic biomass such as source-separated organic (SSO) waste is particularly attractive since it is widely available, often at a negative cost, reduce the land depletion from using food-based biomass for ethanol production and reduce the amount of generated waste. Therefore, in order to meet the future fuel demands and cope with increasing volume of municipal waste this study was a first attempt to use SSO as a feedstock for ethanol production. The main objectives of the study were: a) to compare standard and modified celluloseorganic- solvent-based lignocellulosic fractionation (COSLIF) pretreatment of SSO waste for ethanol production in terms of enzyme savings, sugar formation and ethanol yields; b) to produce ethanol from SSO by using modified COSLIF pretreatment and fermentation with two different recombinant strains: Z. mobilis 8b and S. cerevisiae DA2416; and c) to develop experimental kinetic model capable of predicting behavior of batch SSCF on SSO waste with different SSO substrate concentrations using Berkeley Madonna program. Based on the obtained results, it was found that SSO is an excellent feedstock material for ethanol conversion. The efficiency of modified COSLIF pretreatment was improved by 20% compared to standard method using ethanol washing of pretreated SSO samples during the experimental procedures instead of acetone. On average, glucose yield from SSO samples pretreated by modified COSLIF was about 90% compared to 10% for untreated samples. S. cerevisiae DA2416 outperformed Z. mobilis 8b on ethanol yields during the fermentation process, with 0.50 g ethanol/g potential sugar fed on SSO in less than 5 days, with a 96% cellulose conversion, totalling in 150 g/L ethanol produced. A kinetic model with newly integrated values of experimentally defined SSO feedstock constants was proven to predict the ethanol yield accurately with substrate concentration ranges of 20 g/L - 50 g/L. Model prediction at higher substrate concentration (e.g. 100 g/L) deviated from the experimental values, suggesting that ethanol inhibition is a major factor in bioethanol conversion.

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