Dilute sulfuric acid pretreatment of corn stover for enzymatic hydrolysis and efficient ethanol production by recombinant Escherichia coli FBR5 without detoxification

Avcı, Ayşe; Saha, Badal C.; Kennedy, Gregory J.; Cotta, Michael A.

doi:10.1016/j.biortech.2013.05.002

Cited by 56 publications

(38 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Interestingly, aqueous ammonia can destroy the lignin barrier even at room temperature but it requires a longer duration. The widely used sulfuric acid pretreatment is conducted at 130-200°C for 15-60 min with a concentration of 0.98-2 % (v/v) sulfuric acid (Avci et al 2013a;Feng et al 2014;Kumar et al 2009;Lloyd and Wyman 2005;Qin et al 2012;Shen and Wyman 2011). Alkali salt pretreatment utilizes a 0.05-0.30 % (w/w) alkali solution to treat cellulosic biomasses at less than 100°C for 10-60 min (Feng et al 2014;Rasmussen et al 2014).…”

Section: Feedstocks For Abe Fermentationmentioning

confidence: 99%

Microbial inhibitors: formation and effects on acetone-butanol-ethanol fermentation of lignocellulosic biomass

Baral

Shah

2014

Appl Microbiol Biotechnol

140

View full text Add to dashboard Cite

Biobutanol is a promising biofuel due to the close resemblance of its fuel properties to gasoline, and it is produced via acetone-butanol-ethanol (ABE) fermentation using Clostridium species. However, lignin in the crystalline structure of the lignin-cellulose-hemicellulose biomass complex is not readily consumed by the Clostridium; thus, pretreatment is required to degrade this complex. During pretreatment, some fractions of cellulose and hemicellulose are converted into fermentable sugars, which are further converted to ABE. However, a major setback resulting from common pretreatment processes is the formation of sugar and lignin degradation compounds, including weak acids, furan derivatives, and phenolic compounds, which have inhibitory effects on the Clostridium. In addition, butanol concentration above 13 g/L in the fermentation broth is itself toxic to most Clostridium strain(s). This review summarizes the current state-of-the-art knowledge on the formation of microbial inhibitors during the most common lignocellulosic biomass pretreatment processes. Metabolic effects of inhibitors and their impacts on ABE production, as well as potential solutions for reducing inhibitor formation, such as optimizing pretreatment process parameters, using inhibitor tolerant strain(s) with high butanol yield ability, continuously recovering butanol during ABE fermentation, and adopting consolidated bioprocessing, are also discussed.

show abstract

Section: Feedstocks For Abe Fermentationmentioning

confidence: 99%

Microbial inhibitors: formation and effects on acetone-butanol-ethanol fermentation of lignocellulosic biomass

Baral

Shah

2014

Appl Microbiol Biotechnol

140

View full text Add to dashboard Cite

show abstract

“…Topics that have been the focus of research in recent years include pretreatment 5), 6) , enzyme development 7) , production or detoxification of fermentation inhibitors 8), 9) , development of ethanol producing microorganisms 10) and reactor setup 11) , and system analysis and development 12), 13) . In the ethanol production process, promoting cellulose hydrolysis to produce glucose is a challenge.…”

Section: Introductionmentioning

confidence: 99%

Comparative Study of Hydrothermal Pretreatment of Eucalyptus and Oil Palm Empty Fruit Bunch for Ethanol Fermentation

Matsumura

Fukutomi

Uemura³

2014

J. Jpn. Petrol. Inst.

View full text Add to dashboard Cite

Effective energy production from lignocellulosic biomass is one of the most important research topics to employing biomass as a widely used energy source. Using hydrothermal pretreatment, ethanol can be effectively produced from the lignocellulosic biomass. However, the effects of using different feedstock species on ethanol production have not yet been elucidated. In this study, eucalyptus and oil palm empty fruit bunch were selected for hydrothermal pretreatment, followed by enzymatic hydrolysis and ethanol fermentation in order to compare their reaction characteristics. The effect of hydrothermal pretreatment temperature was studied. Furfural, acetic acid, formic acid, and vanillin were studied in the context of being fermentation inhibitors. Differences in glucose production were observed when different feedstocks were used in the hydrothermal pretreatment step, whereas both inhibitor production and its effect on fermentation were the same regardless of feedstock.

show abstract

“…The total sugar in this research was also greater than the previous researches with hydrothermal and acidic pretreatment (Avci et al, 2013;Saha et al, 2013). The overall analysis of this research and comparison with previous studies suggests that two-stage pretreatment with larger particle size (about 15 mm) will be one of the promising alternatives in terms of pretreatment performance and commercial bio-fuel production.…”

Section: Enzymatic Hydrolysis Of Pretreated Corn Stalkmentioning

confidence: 54%

Fermentable sugars and microbial inhibitors formation from two-stage pretreatment of corn stalk with variation in particle size and severity factor

Baral¹,

Li²,

Jha³

2015

Afr. J. Biotechnol.

View full text Add to dashboard Cite

Microbial inhibitors including weak acids, furan derivatives and phenolic compounds are key problems of cellulosic bio-fuels production by fermentation. Most of these inhibitors are sugars and lignin degradation compounds, which are almost unavoidable during pretreatment processes. While, most of the one stage pretreatment has been conducted at high severity factors of 3.5 or more to get high sugar yield, with increase in severity factor, high concentration of microbial inhibitors were formed and significantly affected downstream biofuel yield. Thus, a two-stage pretreatment of corn stalk, hydrothermal followed by oxalic acid, under low severity factor and its enzymatic degradability was investigated in this study to identify fermentable sugar production and corresponding microbial inhibitors formation. Additionally, effect of equivalent severity factors of 2 to 3.5 and particle sizes of 1 to 35 mm were also studied systematically. Particle size of 15 mm was found as an optimum size at an equivalent severity factor of 2.5. Sugars 61.99 ± 0.03 g and inhibitors 5.12 ± 0.01 g from 100 g of corn stalk were obtained at the optimum particle size and pretreatment condition. The highest glucan conversion and recovery at the optimum conditions were 92.95± 0.08 and 78.42± 0.07%, respectively. Overall, the two-stage pretreatment process with the larger particle size and low equivalent severity factor could be an alternative to reduce microbial inhibitors formation and excessive biomass processing cost.

show abstract

Dilute sulfuric acid pretreatment of corn stover for enzymatic hydrolysis and efficient ethanol production by recombinant Escherichia coli FBR5 without detoxification

Cited by 56 publications

References 31 publications

Microbial inhibitors: formation and effects on acetone-butanol-ethanol fermentation of lignocellulosic biomass

Microbial inhibitors: formation and effects on acetone-butanol-ethanol fermentation of lignocellulosic biomass

Comparative Study of Hydrothermal Pretreatment of Eucalyptus and Oil Palm Empty Fruit Bunch for Ethanol Fermentation

Fermentable sugars and microbial inhibitors formation from two-stage pretreatment of corn stalk with variation in particle size and severity factor

Contact Info

Product

Resources

About