Industrial robust yeast isolates with great potential for fermentation of lignocellulosic biomass.
The search of robust microorganisms is essential to design sustainable processes of second generation bioethanol. Yeast strains isolated from industrial environments are generally recognised to present an increased stress tolerance but no specific information is available on their tolerance towards inhibitors that come from the pretreatment of lignocellulosic materials. In this work, a strategy for the selection of different yeasts using hydrothermal hydrolysate from Eucalyptus globulus wood, containing different concentrations of inhibitors, was developed. Ten Saccharomyces cerevisiae and four Kluyveromyces marxianus strains isolated from industrial environments and four laboratory background strains were evaluated. Interestingly, a correlation between final ethanol titer and percentage of furfural detoxification was observed. The results presented here highlight industrial distillery environments as a remarkable source of efficient yeast strains for lignocellulosic fermentation processes. Selected strains were able to resourcefully degrade furfural and HMF inhibitors, producing 0.8g ethanol/Lh corresponding to 94% of the theoretical yield.
CEB - Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal. Electronic address: franciscopereira@deb.uminho.pt.
Francisco B
FB
Pereira
CEB - Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal. Electronic address: aloia@ceb.uminho.pt.
Aloia
A
Romaní
Biorefinery and Food Engineering Laboratory, Food Research Department/School of Chemistry, Autonomous University of Coahuila, Blvd. V. Carranza e Ing. José Cárdenas Valdés, 25280 Saltillo, Coahuila, Mexico. Electronic address: hector_ruiz_leza@uadec.edu.mx.
Héctor A
HA
Ruiz
CEB - Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal. Electronic address: jateixeira@deb.uminho.pt.
José A
JA
Teixeira
CEB - Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal. Electronic address: luciliad@deb.uminho.pt.
Lucília
L
Domingues
D056804:Biofuels; D018533:Biomass; D019149:Bioreactors; D000431:Ethanol / Q000378:metabolism; D005052:Eucalyptus; D005285:Fermentation; D005662:Furaldehyde / Q000031:analogs & derivatives / Q000032:analysis; D007716:Kluyveromyces / Q000302:isolation & purification* / Q000378:metabolism; D008031:Lignin / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000302:isolation & purification* / Q000378:metabolism
D056804:Biofuels; C036909:lignocellulose; D000431:Ethanol; C008046:5-hydroxymethylfurfural; D008031:Lignin; D005662:Furaldehyde
Bio-ethanol; Inhibitor kinetics; Lignocellulose fermentation; PE-2; Pre-treatment