Abstract: Several fungi (Aspergillus niger, A. terreus, Cochliobolus specifer, Myrothecium verrucaria. Rhizoctonia solani, Spicaria fusispora. Penicillium sp., and Gliocladium sp.) were isolated from decomposing wheat straw and tested for their ability to utilize whole straw and its components, holocellulose (hemicellulose and cellulose) and cellulose, for the production of single-cell protein (SCP). It was found that C. specifer was the most efficient fungus for protein synthesis with the three substrates. Using potassium nitrate as N source in mixtures of 0.04 g N/g substrate (0.04% wt./vol.) at pH 4.5, it was found that incubation periods of 3. 4, and 5 days were optimal for protein production on cellulose and holocellulose fractions, and whole straw, respectively. Whole native straw was found to be the most recalcitrant to bioconversion into SCP; however, protein production was almost doubled when the lignin component was removed using a mixture of sodium chlorite and acetic acid.

Abstract: Continuous operation of a biomethanation plant could be acheved more readily if mixtures of biomass and organic wastes could be utilized as feedstock. The research reported in this paper was directed to a laboratory evaluation of a blend of terrestrial and aquatic biomass with organic wastes as an anaerobic digester feed. Specifically, a blend of water hyacinth, Coastal Bermuda grass, the combustible fraction of municipal solid waste, and a small quantity of sludge was digested under standard, high-rate mesophilic conditions. Good methane production was achieved without the addition of external nutrients. As expected, biodegradabilities in decreasing order were hemicellulose, cellulose, crude protein, and lignin. The digester effluent was easily dewatered by filtration without chemical conditioning. Pretreatment of the feed slurry with 3 wt % sodium hydroxide solution under ambient conditions improved methane yield about 20% over that of the fresh untreated feed. A kinetic analysis of the experimental data indicated that hydrolysis or acidification was the rate limiting step of digestion of the biomass-waste blend. It was concluded from this work that biomass-waste blends of the type studied in this work can sustain anaerobic digestion under conventional conditions for long periods with little difficulty. Substantial improvements in methane yield shouldmore » be possible, however, by use of advanced digestion techniques because methane recovery efficiencies in this work ranged up to about 46%.« less

Abstract: Preliminary studies show minimal conversion of wood by sulfur dioxide at pressures of 38 psi at room temperature. Evaluation studies of Rut-C-30 and Rut-L-5 Trichoderma viride strains were compared. Studies on the continuous production system by manipulating temperature, pH, Tween 80 level substrate concentration, and dilution rate were performed. The known major components of cellulases were characterized. Studies on the reduction of the cost of producing sugar from corn stover were performed. Development of medium for continuous ethanol fermentation is discussed. Experiments show that the growth limiting factors for continuous fermentation were in the yeast extract. Biotin, pantothenic acid, and pyridoxine appear to be growth limiting factors. Addition of other vitamins had no effect on cell yield but increased ethanol production. The flash ferm process is discussed. Utilization of hemicellulose sugars is described. (DC)

Abstract: Leucomycin A1 (LM A1) was converted to leucomycin A3 (LM A3) by Streptomyces kitasatoensis is glucose-containing medium. On the other hand, butyrate, one of the precursors of the aglycone, repressed the bioconversion of LM A1 to A3. The role of butyrate has been examined in connection with that of glucose. It was found that the production of the enzyme which catalyzes the acetylation at C–3 of aglycone was induced by glucose, and that the induction was remarkably repressed by butyrate. Cerulenin, a specific inhibitor of fatty acid synthesis, was effectively employed for the bioconversion experiments.

Abstract: A two part article, Cellulose to Ethanol Process and Technical and Economic Evaluation, is presented. Bioconversion technology included to remove or decrease the volume of solid waste and to provide ethyl alcohol and other chemicals which can be utilized to supplant fossil fuel sources as a feedstock. The cellulose to ethanol process included: feedstock handling and pretreatment, enzyme production, yeast production, simultaneous saccharification fermentation (SSF), and ethanol recovery. With respect to conversion to ethanol or other chemicals, three factors must be considered regarding the susceptibility of native cellulose to biodegradation, its insolubility in water, extent of liquefaction, and crystallinity. A detailed study was made of the technical and economic feasibility of the process. The technical feasibility was demonstrated by research work carried out at the Gulf Oil Chemicals Company. The commercial process, based on producing 25 MM gallons per year alcohol, showed a more favorable selling price than grain fermentation and synthetic alcohols with 100% investor equity capital financing. With municipal bond financing, cellulosic waste alcohol yielded much greater profitability or much lower selling prices to obtain a 15% return on investor equity. 6 figures, 3 tables.

Abstract: The bioconversion of m-hydroxybenzoate to 2,3-dihydroxybenzoate in high yield is accomplished employing a mutant strain of Pseudomonas testosteroni.

Abstract: Using advanced petroleum recovery techniques, it may be possible to produce half as much oil from existing U.S. wells as has been previously produced. Even limited use of tertiary oil recovery methods could substantially add to U.S. domestic oil production and decrease U.S. dependence on foreign energy imports. Micellar flooding, a promising technique for enhanced oil recovery, uses chemicals to free oil from formations depleted by conventional techniques. Using micellar flooding techniques to produce additional petroleum equivalent to 1% of U.S. current consumption could require approximately 75 million lb of high viscosity polymer, 750 million lb of surfactant, and 400 million lb of 3 to 5 carbon alcohols annually. The availability of better, cheaper chemical materials for this process could decrease the overall process cost and thereby increase its use. Synthesis of micellar flood chemicals from waste materials could meet the requirements of low cost chemicals without large scale market dislocations. With the exception of petroleum, wood is the largest single U.S. commodity. Because this industry is experienced in chemical recovery and has major landholdings, it is a good potential source for micellar flood chemicals. Most of the wood pulp used to produce the quarter ton of paper consumed per capita per year in the U.S. is produced by cooking, or digesting, wood chips in a chemical solution. These pulping processes have effluent streams which contain substantial amounts of dissolved lignins, lignin breakdown products, and carbohydrates. There is a substantial economic incentive to use these materials as feedstocks for the production of high-valued micellar flood chemicals. The pulp and paper industries have practiced chemical recovery for almost a century. The largest chemical recycle processes are the internal recycle of inorganic salts for reuse in pulping. This is coupled with the use of waste organic compounds in the liquor as a fuel for directly-fired evaporation processes. Diversion of effluent and low valued streams for chemical recovery using fermentation, purification, or synthesis methods appears technically feasible in several cases. The use of new recovery processes could yield a variety of different wood-effluent based products. Some of the sugar acids in pulping liquors might be used as sequestering agents in reservoirs where there are large amounts of multivalent cations in flood brines. Fermentation production of high viscosity polymers, sequestering agents, and coagent alcohols appears worth further investigation. Tall oil acids and their derivatives can be used as surfactants in some reservoirs. Some waste constituents may adsorb preferentially on formations and thereby reduce loss of surfactants and other higher-valued chemicals. The development of processes for the production of chemicals, including those chemicals used in micellar floods, from pulp and paper industry waste and low-valued process streams could provide economic benefit to the industry and to the nation.

Abstract: This article reviews the fundamental biochemical concepts underlying the bioconversion lignocellulose materials. Data are also given on the anticipated potential yields 0/ ethyl alcohol/rom the most important ceUuJoslc waste products gene1'(Used In South Africa.