Recycle of enzymes and substrate following enzymatic hydrolysis of steam-pretreated aspenwood
The commercial production of chemicals and fuels from lignocellulosic residues by enzymatic means still requires considerable research on both the technical and economic aspects. Two technical problems that have been identified as requiring further research are the recycle of the enzymes used in hydrolysis and the reuse of the recalcitrant cellulose remaining after incomplete hydrolysis. Enzyme recycle is required to lower the cost of the enzymes, while the reuse of the spent cellulose will lower the feedstock cost. The conversion process studied was a combined enzymatic hydrolysis and fermentation (CHF) procedure that utilized the cellulolytic enzymes derived from the fungus Trichoderma harzianum E58 and the yeast Saccharomyces cerevisiae. The rate and extent of hydrolysis and ethanol production was monitored as was the activity and hydrolytic potential of the enzymes remaining in the filtrate after the hydrolysis period. When a commercial cellulose was used as the substrate for a routine 2-day CHF process, 60% of the original filter paper activity could be recovered. When steam-treated, water-extracted aspenwood was used as the substrate, only 13% of the original filter paper activity was detected after a similar procedure. The combination of 60% spent enzymes with 40% fresh enzymes resulted in the production of 30% less reducing sugars than the original enzyme mixture. Since 100% hydrolysis of the cellulose portion is seldom accomplished in an enzymatic hydrolysis process, the residual cellulose was used as a substrate for the growth of T. harzianum E58 and production of cellulolytic enzymes. The residue remaining after the CHF process was used as a substrate for the production of the cellulolytic enzymes. The production of enzymes from the residue of the Solka Floc hydrolysis was greater than the production of enzymes from the original Solka Floc. (Refs. 14).
- Research Organization:
- Forintek Canada Corp., 800 Montreal Road, Ottawa, Ontario, Canada
- OSTI ID:
- 5493471
- Journal Information:
- Biotechnol. Bioeng.; (United States), Vol. 30:4
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
CELLULASE
RECYCLING
ENZYMES
ETHANOL
BIOSYNTHESIS
LIGNIN
ENZYMATIC HYDROLYSIS
RESIDUES
WOOD
ASPENS
CELLULOLYTIC ACTIVITY
CELLULOSE
CHEMICAL FEEDSTOCKS
COMMERCIALIZATION
COST
ECONOMICS
EXTRACTION
FERMENTATION
FILTERS
FUELS
HYDROLYSIS
PAPER
PRODUCTION
RECOMMENDATIONS
RECOVERY
REDUCTION
SACCHARIDES
SACCHAROMYCES CEREVISIAE
STEAM
SUBSTRATES
TECHNOLOGY ASSESSMENT
TRICHODERMA
WATER
ALCOHOLS
BIOCONVERSION
CARBOHYDRATES
CHEMICAL REACTIONS
DECOMPOSITION
ENZYME ACTIVITY
FUNGI
GLYCOSYL HYDROLASES
HYDROGEN COMPOUNDS
HYDROLASES
HYDROXY COMPOUNDS
LYSIS
MICROORGANISMS
O-GLYCOSYL HYDROLASES
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PLANTS
POLYSACCHARIDES
SACCHAROMYCES
SEPARATION PROCESSES
SOLVOLYSIS
SYNTHESIS
TREES
YEASTS
140504* - Solar Energy Conversion- Biomass Production & Conversion- (-1989)