Evaluation of a recombinant Klebsiella oxytoca strain for ethanol production from cellulose by simultaneous saccharification and fermentation: comparison with native cellobiose-utilising yeast strains and performance in co-culture with thermotolerant yeast and Zymomonas mobilis

Abstract Sweet potato medium containing 230.0 g•kg-1 liquefied starch was used for simultaneous saccharification and fermentation (SSF) for fuel ethanol production. Glucose releasing rate was controlled by the initial addition of incremental glucoamylase. The increasing rates of glucose concentration display a positive relationship when glucoamylase is added in early stage (0 to 8 hours (h)). Serious cells growth inhibition occurred in the early stage when 1.0 g•kg-1 glucoamylase is added, whereas glucose providing limitation occurred in the batch with 0.2 g•kg-1 glucoamylase added in later stage (64 to 80 h). The optimum dosage of glucoamylase was 0.8 g•kg-1, where a final ethanol concentration of 118.2 g•kg-1 was attained within 72 h. The results of our study suggest cell growth inhibition and substrate providing limitation can be avoided simultaneously by adding a proper dosage of glucoamylase. It is indicated further that cells growth inhibition in early stage in the batch with 1.0 g•kg-1 glucoamylase added was due to the high increasing rate of initial glucose concentration, but not the high overall glucose concentration.

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Simultaneous Saccharification and Fermentation of Aqueous Ammonia Pretreated Oat Straw for Ethanol Production

Biological Engineering Transactions ◽

10.13031/2013.39816 ◽

2011 ◽

Vol 4 (3) ◽

pp. 157-166 ◽

Cited By ~ 6

Author(s):

B. Karki ◽

B. Rijal ◽

S. W. Pryor

Keyword(s):

Ethanol Production ◽

Simultaneous Saccharification And Fermentation ◽

Aqueous Ammonia ◽

Oat Straw ◽

Simultaneous Saccharification

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Acetone–butanol–ethanol production from Kraft paper mill sludge by simultaneous saccharification and fermentation

Bioresource Technology ◽

10.1016/j.biortech.2015.10.102 ◽

2016 ◽

Vol 200 ◽

pp. 713-721 ◽

Cited By ~ 49

Author(s):

Wenjian Guan ◽

Suan Shi ◽

Maobing Tu ◽

Yoon Y. Lee

Keyword(s):

Ethanol Production ◽

Simultaneous Saccharification And Fermentation ◽

Paper Mill ◽

Paper Mill Sludge ◽

Kraft Paper ◽

Acetone Butanol Ethanol ◽

Simultaneous Saccharification

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Ethanol Production from Corn Stover Using Soaking Pretreatment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.171-172.261 ◽

2010 ◽

Vol 171-172 ◽

pp. 261-265

Author(s):

Zhuang Zuo ◽

Xiu Shan Yang

Keyword(s):

Ethanol Production ◽

Corn Stover ◽

Simultaneous Saccharification And Fermentation ◽

Pichia Stipitis ◽

Liquid Ratio ◽

Mild Conditions ◽

Whole Process ◽

Conversion Rates ◽

Mild Temperature ◽

Simultaneous Saccharification

Corn stover was pretreated using different soaking conditions at mild temperature. Among the tested conditions, the best was 1% NaOH+8% NH4OH，50°C，48 h, Solid-to-liquid ratio 1:10. The results showed that soaking pretreatment achieved 63.6% deligniﬁcation, retained the xylan and glucan. After enzymatic hydrolysis, conversion rates of xylan and glucan were 70.9% and 78.5%, respectively. The pretreated filtration re-soaking cause 52.7% xylan and 65.0% glucan conversion. NaOH+NH4OH treatment can be performed under mild conditions, gives a good buffering effect, low carbohydates degradation and extensive removal of lignin. Additionally, simultaneous sacchariﬁcation and fermentation was conducted with pretreated corn stover to assess the ethanol production. For the whole process, 0.15g ethanol /g corn stover was achieved using Saccharomyces cerevisiae Y5, and 0.19g ethanol /g corn stover when using Pichia stipitis.

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