Butanol Tolerance in a Selection of Microorganisms

National Renewable Energy Laboratory, National Bioenergy Center, Golden, CO 80401, USA.
Applied biochemistry and biotechnology (Impact Factor: 1.74). 05/2009; 153(1-3):13-20. DOI: 10.1007/s12010-008-8460-4
Source: PubMed


Butanol tolerance is a critical factor affecting the ability of microorganisms to generate economically viable quantities of butanol. Current Clostridium strains are unable to tolerate greater than 2% 1-butanol thus membrane or gas stripping technologies to actively remove butanol during fermentation are advantageous. To evaluate the potential of alternative hosts for butanol production, we screened 24 different microorganisms for their tolerance to butanol. We found that in general, a barrier to growth exists between 1% and 2% butanol and few microorganisms can tolerate 2% butanol. Strains of Escherichia coli, Zymomonas mobilis, and non-Saccharomyces yeasts were unable to surmount the 2% butanol growth barrier. Several strains of Saccharomyces cerevisiae exhibit limited growth in 2% butanol, while two strains of Lactobacillus were able to tolerate and grow in up to 3% butanol.

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Available from: Eric P. Knoshaug, Jun 16, 2015
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    • "After incubation, the isolated colonies were inoculated into agar plate containing 1 to 5 % (v/v) butanol concentration. Several rounds of screening were performed to purify and to isolate strains with high butanol tolerance [1]. "
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    • "One of the biggest problems faced by the industry is the low butanol tolerance exhibited by most microorganisms. While ethanol-producing organisms such as S. cerevisiae can tolerate ethanol concentrations close to 20% v/v, butanol producers are generally limited to 2-3% v/v [Knoshaug & Zhang (2009)]. This leads to increased downstream separation costs and larger production equipment. "
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    • "Butanol tolerance was checked in MSA plates containing 1 to 5 % (v/v) butanol with the above said conditions. Several rounds of screening were performed to purify and isolate strains with high butanol tolerance (Sardssai and Bhosle, 2002; Knoshaug et al., 2009). The isolated strain was stored at -20 °C for further use. "
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