Simultaneous saccharification and fermentation of steam-pretreated spruce to ethanol.
Ethanol production was studied in simultaneous saccharification and fermentation (SSF) of steam-pretreated spruce at 42 degrees C, using a thermotolerant yeast. Three yeast strains of Kluyveromyces marxianus were compared in test fermentations. SSF experiments were performed with the best of these on 5% (w/w) of substrate, at a cellulase loading of 37 filter paper units/g of cellulose, and a beta-glucosidase loading of 38 IU/g of cellulose. The detoxification of the substrate and the lack of pH control in the experiments increased the final ethanol concentration. The final ethanol yield was 15% lower compared to SSF with Saccharomyces cerevisiae at 37 degrees C, owing to the cessation of ethanol fermentation after the first 10 h.
Bollók
M
M
Department of Agricultural Chemical Technology, Technical University of Budapest, Hungary.
Réczey
K
K
Zacchi
G
G
D002480:Cellulase / Q000378:metabolism*; D032462:Cycadopsida; D000431:Ethanol; D005285:Fermentation; D007716:Kluyveromyces / Q000502:physiology*; D011134:Polysaccharides / Q000032:analysis; D013227:Steam; D014197:Trees; D001617:beta-Glucosidase / Q000378:metabolism*
D011134:Polysaccharides; D013227:Steam; D000431:Ethanol; D001617:beta-Glucosidase; D002480:Cellulase