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Title: Bioconversion of distillers’ grains hydrolysates to advanced biofuels by an Escherichia coli co-culture

Abstract

Here, the first generation bioethanol production utilizes the starch fraction of maize, which accounts for approximately 60% of the ash-free dry weight of the grain. Scale-up of this technology for fuels applications has resulted in a massive supply of distillers’ grains with solubles (DGS) coproduct, which is rich in cellulosic polysaccharides and protein. It was surmised that DGS would be rapidly adopted for animal feed applications, however, this has not been observed based on inconsistency of the product stream and other logistics-related risks, especially toxigenic contaminants. Therefore, efficient valorization of DGS for production of petroleum displacing products will significantly improve the techno-economic feasibility and net energy return of the established starch bioethanol process. In this study, we demonstrate ‘one-pot’ bioconversion of the protein and carbohydrate fractions of a DGS hydrolysate into C4 and C5 fusel alcohols through development of a microbial consortium incorporating two engineered Escherichia coli biocatalyst strains.

Authors:
ORCiD logo [1];  [1];  [1];  [1];  [1];  [1]
  1. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1411235
Report Number(s):
SAND-2017-12329J
Journal ID: ISSN 1475-2859; PII: 804
Grant/Contract Number:
AC04-94AL85000
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Microbial Cell Factories
Additional Journal Information:
Journal Volume: 16; Journal Issue: 1; Journal ID: ISSN 1475-2859
Publisher:
BioMed Central
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; Distillers’ grains with solubles (DGS); Microbial co-culture; One-pot bioconversion; Fusel alcohol; Algae hydrolysate

Citation Formats

Liu, Fang, Wu, Weihua, Tran-Gyamfi, Mary B., Jaryenneh, James D., Zhuang, Xun, and Davis, Ryan W. Bioconversion of distillers’ grains hydrolysates to advanced biofuels by an Escherichia coli co-culture. United States: N. p., 2017. Web. doi:10.1186/s12934-017-0804-8.
Liu, Fang, Wu, Weihua, Tran-Gyamfi, Mary B., Jaryenneh, James D., Zhuang, Xun, & Davis, Ryan W. Bioconversion of distillers’ grains hydrolysates to advanced biofuels by an Escherichia coli co-culture. United States. doi:10.1186/s12934-017-0804-8.
Liu, Fang, Wu, Weihua, Tran-Gyamfi, Mary B., Jaryenneh, James D., Zhuang, Xun, and Davis, Ryan W. Thu . "Bioconversion of distillers’ grains hydrolysates to advanced biofuels by an Escherichia coli co-culture". United States. doi:10.1186/s12934-017-0804-8. https://www.osti.gov/servlets/purl/1411235.
@article{osti_1411235,
title = {Bioconversion of distillers’ grains hydrolysates to advanced biofuels by an Escherichia coli co-culture},
author = {Liu, Fang and Wu, Weihua and Tran-Gyamfi, Mary B. and Jaryenneh, James D. and Zhuang, Xun and Davis, Ryan W.},
abstractNote = {Here, the first generation bioethanol production utilizes the starch fraction of maize, which accounts for approximately 60% of the ash-free dry weight of the grain. Scale-up of this technology for fuels applications has resulted in a massive supply of distillers’ grains with solubles (DGS) coproduct, which is rich in cellulosic polysaccharides and protein. It was surmised that DGS would be rapidly adopted for animal feed applications, however, this has not been observed based on inconsistency of the product stream and other logistics-related risks, especially toxigenic contaminants. Therefore, efficient valorization of DGS for production of petroleum displacing products will significantly improve the techno-economic feasibility and net energy return of the established starch bioethanol process. In this study, we demonstrate ‘one-pot’ bioconversion of the protein and carbohydrate fractions of a DGS hydrolysate into C4 and C5 fusel alcohols through development of a microbial consortium incorporating two engineered Escherichia coli biocatalyst strains.},
doi = {10.1186/s12934-017-0804-8},
journal = {Microbial Cell Factories},
number = 1,
volume = 16,
place = {United States},
year = {Thu Nov 09 00:00:00 EST 2017},
month = {Thu Nov 09 00:00:00 EST 2017}
}

Journal Article:
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