influence of bark on the fermentation of Douglas-fir whitewood pre-hydrolysates

• Published in: Applied microbiology and biotechnology 2002, Vol.59 (4/5), p.443-448
• Main Authors: Robinson, J, Keating, J.D, Boussaid, A, Mansfield, S.D, Saddler, J.N
• Format: Article
• Language: English
• Subjects: bark; Biofuel production; Biological and medical sciences; Biotechnology; Biotechnology - methods; Carbohydrate Metabolism; Energy; Ethanol; Ethanol - metabolism; ethanol production; feedstocks; Fermentation; Fundamental and applied biological sciences. Psychology; furfural; Hydrolysis; hydroxymethylfurfural; Industrial applications and implications. Economical aspects; Lignin - chemistry; Lignin - metabolism; Plant Bark - chemistry; Plant Bark - metabolism; Pseudotsuga - chemistry; Pseudotsuga - metabolism; Pseudotsuga menziesii; Saccharomyces cerevisiae; Sugar; sugars; Wood
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-002-1055-z

Douglas-fir (Pseudotsuga menziesii) white-wood was supplemented with increasing concentrations of bark (0-30%) and was pretreated using SO2-catalysed steam explosion. The presence of bark in the feedstock resulted in the decreased recovery of total sugars, furfural and 5-hydroxymethylfurfural in the resultant prehydrolysate. No detrimental impact on monomer sugar recovery was observed. The concentration of lipophilic extractives present in the pre-hydrolysate increased with increasing bark loading, to a maximum of 0.43 g l(-1). The water-soluble pre-hydrolysates were fermented by Saccharomyces cerevisiae to determine the impact of bark on sugar consumption and ethanol production. Despite the inclusion of bark, fermentation of all pre-hydrolysates resulted in the complete consumption of hexose sugars within 48 h. Ethanol yields were greater than 0.43 g g(-1) for ail pre-hydrolysates regardless of bark content, indicating that, up to a content of 30%, bark had a negligible impact on the fermentation of the pre-hydrolysates to ethanol.