Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, March 1, 1977--May 31, 1977
The degradation of cellulosic biomass continues to focus on the anaerobic thermophile Clostridium thermocellum. When grown on crystalline cellulose (MN300) in batch culture, there is an initial rapid accumulation of reducing sugars but the sugars are rapidly metabolized in later times during the fermentation. When grown on Solka floc with periodic addition of the substrate, there is a continual accumulation of reducing sugars (xylose, glucose, and cellobiose) as well as ethanol and acetic acid during the entire course of the fermentation. In the presence of surfactant in the growth medium, there is an increased appearance of extracellular cellulases. A chemically defined medium is being developed for growth Cl. thermocellum in order to study the enzyme regulations. Lastly, a trinitrophenyl-carboxylmethyl cellulose substrate for determining cellulose activity appears to be a promising and rapid assay. Progress in the genetic manipulations has been cautious but promising. Preliminary evidence leads to optimistic projection on the presence of plasmids and bacteriophage in Cl. thermocellum. The production of chemical feedstocks continues to focus on acrylic acid, acetone/butanol and acetic acid. Studies with cell free extracts of Clostridium propionicum have shown the production and accumulation of acrylic acid from lactic acid. The use of electron acceptor in cell-free systems has shown effective prevention on the reduction of acrylic acid to propionic acid. Medium development and strain selection using available acetone/butanol producing Cl. acetobutylicum have been initiated. There is every indication that these strains are capable to produce mixed solvents close to the theoretical maximum yield. An accurate and rapid method for quantifying acetic acid was developed. This technique is being used to examine the pertinent parameters on the production of acetic acid by Clostridium thermoaceticum.
- Research Organization:
- Massachusetts Inst. of Tech., Cambridge (USA). Dept. of Nutrition and Food Science
- DOE Contract Number:
- EG-77-S-02-4198
- OSTI ID:
- 5200095
- Report Number(s):
- COO/4198-2
- Country of Publication:
- United States
- Language:
- English
Similar Records
Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, June 1, 1977--August 31, 1977
Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks
Related Subjects
CELLULOSE
BIODEGRADATION
ENZYMATIC HYDROLYSIS
CHEMICAL FEEDSTOCKS
BIOSYNTHESIS
ACETIC ACID
ACETONE
ACRYLIC ACID
BUTANOLS
CELLOBIOSE
CELLULASES
CLOSTRIDIUM
ENZYMES
ETHANOL
FERMENTATION
GLUCOSE
METABOLISM
RESEARCH PROGRAMS
SUBSTRATES
SURFACTANTS
XYLOSE
ALCOHOLS
ALDEHYDES
BACTERIA
BIOCONVERSION
CARBOHYDRATES
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
DECOMPOSITION
DISACCHARIDES
HEXOSES
HYDROLASES
HYDROLYSIS
HYDROXY COMPOUNDS
KETONES
LYSIS
MICROORGANISMS
MONOCARBOXYLIC ACIDS
MONOSACCHARIDES
OLIGOSACCHARIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
PENTOSES
POLYSACCHARIDES
SACCHARIDES
SOLVOLYSIS
SYNTHESIS
140504* - Solar Energy Conversion- Biomass Production & Conversion- (-1989)