Efforts have been made to develop a simple chemically defined resuspended mycelial system which m... more Efforts have been made to develop a simple chemically defined resuspended mycelial system which may be used for carrying out fundamental studies regarding the mechanism of kojic acid biosynthesis. As a first step, it was found that mycelia grown in yeast extract sucrose (YES) medium and resuspended in YES medium or in 0.2 M phosphate buffer, pH 6.5, supplemented with 20% glucose or sucrose produced kojic acid almost to the same extent as in the case of growth medium. No kojic acid was formed if buffers or media used for resuspension lacked carbohydrate. Intact mycelia preincubated in buffer alone for 7 days and 3-week-old mycelia could still form kojic acid in large amounts if resuspended in buffer containing glucose. The amount of kojic acid produced by the intact mycelia was found to be more than that produced by the disrupted mycelia. In contrast with static resuspension studies, when Aspergillus flavus mycelia were resuspended in flasks placed on a rotary shaker, much smaller am...
Eight strains of Kluyveromyces marxianus were screened, and all of them were found to ferment the... more Eight strains of Kluyveromyces marxianus were screened, and all of them were found to ferment the aldopentose d -xylose directly to ethanol under aerobic conditions. One of these strains, K. marxianus SUB-80-S, was grown in a medium containing 20 g of d -xylose per liter, and the following results were obtained: maximum ethanol concentration, 5.6 g/liter; ethanol yield, 0.28 g of ethanol per g of d -xylose (55% of theoretical); maximum specific growth rate, 0.12 h −1 ; 100% d -xylose utilization was completed in 48 h.
Recovery of lignin from different processes—kraft process, steam explosion process, organosolv pr... more Recovery of lignin from different processes—kraft process, steam explosion process, organosolv process—is discussed in this chapter. Commercial suppliers of lignin are also listed.
Résumé/Abstract Several yeast strains were tested for their ethanol-producing ability, and one of... more Résumé/Abstract Several yeast strains were tested for their ethanol-producing ability, and one of the most promising was selected for ethanol production in high concentrations. The yeast cells were immobilized in calcium alginate gel beads and were stabilized by ...
Hexokinase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glucose dehydrog... more Hexokinase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glucose dehydrogenase, glucose oxidase and gluconate dehydrogenase have been demon-strated in mycelial homogenates from a strain of Aspergillus JEavus that produces considerable ...
Some recovered paper is utilised outside the paper industry for construction purposes, insulation... more Some recovered paper is utilised outside the paper industry for construction purposes, insulation, mailing bags and other end uses. In most of the countries, no accurate data is available to estimate recovered paper utilisation for applications other than the paper industry. In addition to use in the paper industry, over 8% of collected paper is used in other applications: construction materials, animal beddings, composting and energy. Recycling is considered better than composting in the hierarchy of materials management. In this chapter, uses of recovered paper other than papermaking are discussed.
Alkali treatment of corn stover improves the availability of cellulose and hemicellulose for enzy... more Alkali treatment of corn stover improves the availability of cellulose and hemicellulose for enzymatic attack. Treatments were carried out for 1 to 60 min at temperatures and NaOH concentrations ranging from 100 to 150 degrees C and 0 to 2%, respectively. Solubilization of the stover and sugar production by enzymatic hydrolysis (Trichoderma viride cellulase) of the solid residue and the
Use of biotechnology in pulp bleaching has attracted considerable attention and achieved interest... more Use of biotechnology in pulp bleaching has attracted considerable attention and achieved interesting results in recent years. Enzymes of the hemicellulolytic type, particularly xylan-attacking enzymes, xylanases are now used commercially in the mills for pulp treatment and subsequent incorporation into bleach sequences. The aims of the enzymatic treatment depend on the actual mill conditions and may be related to environmental demands, reduction of chemical costs or maintenance or even improvement of product quality. The use of oxidative enzymes from white-rot fungi, that can directly attack lignin, is a second-generation approach, which could produce larger chemical savings than xylanase but has not yet been developed to the full scale. It is being studied in several laboratories in Canada, Japan, the U.S.A. and Europe. Certain white-rot fungi can delignify kraft pulps increasing their brightness and their responsiveness to brightening with chemicals. The fungal treatments are too slow but the enzyme manganese peroxidase and laccase can also delignify pulps and enzymatic processes are likely to be easier to optimize and apply than the fungal treatments. Development work on laccase and manganese peroxidase continues. This article presents an overview of developments in the application of hemicellulase enzymes, lignin-oxidizing enzymes and white-rot fungi in bleaching of chemical pulps. The basic enzymology involved and the present knowledge of the mechanisms of the action of enzymes as well as the practical results and advantages obtained on the laboratory and industrial scale are discussed.
Flocculent cells of Kluyveromyces marxianus SM 16-10 were used for batch production of ethanol fr... more Flocculent cells of Kluyveromyces marxianus SM 16-10 were used for batch production of ethanol from the inulin sugars derived from Jeru-salem artichoke tubers. Using 20% initial sugar concentration, a maximum ethanol concentration of 92 g/l was achieved in 7 h, when the flocculent cell concentration was 30 g dry wt./l bioreactor volume. The same flocculent cells were used repeatedly for 7 batch runs starting with fresh medium at the beginning of each run. The ethanol yield was found to be almost constant at about 94% of the theoretical for all the 7 batch cycles, while the maximum ethanol production rate increased from 17.21 g ethanol/I/h during the first batch run to 21 g ethanol/i/h during the last batch run.
The growing interest in the application of arachidonic acid (ARA) in various fields of health and... more The growing interest in the application of arachidonic acid (ARA) in various fields of health and dietary requirements has elicited much attention on the industrial production of ARA-containing oil by the cultivation of Mortierella fungi. For the industrial production of ARA, various studies, such as isolation of a high-potential strain and optimization of culture conditions, have been conducted. Studies i ncluding the investigation of morphology are important because ARA is accumulated in the mycelia, and thus cultivation with high biomass concentration is essential for obtaining a high ARA yield. Combining the results derived from various studies, a high ARA yield was attained in an industrial fermentor. These ARA production techniques are applicable to the production of other polyunsaturated fatty acids (PUFAs), and will contribute to the improvement of fermentation technology especially in the field of fungal cult ivation.
There is a significant opportunity now for investors to build, own, and operate biorefineries at ... more There is a significant opportunity now for investors to build, own, and operate biorefineries at existing pulp and paper sites that will work synergistically and economically for the pulp and paper mill owner and the biorefinery owner. The pulp and paper industry is the world’s largest nonfood biomass collection system. The pulp and paper industry is a mature industry producing low-margin commodity products. But it has the ideal infrastructure, experience, and resources to capitalize on the strategic interest in renewable fuels via the biorefinery. Industry leaders, investors, policy-makers, and others are now beginning to better understand the vital role to be played by biorefineries as we move from a fossil fuel-based energy economy toward a bio-based one. When properly located and operated, the potential of an integrated forest biorefinery is expected to be huge: a very attractive and synergistic business opportunity for both the colocated pulp and paper mill and the biorefinery itself. Biorefineries are a key pathway to our biofuture, displacing fossil fuels and supplying clean, renewable, and carbon neutral energy. Biorefineries fit very well at pulp and paper mills because of their inherent ability to gather and process biomass and create energy from biomass.KeywordsBiorefinery; pulp and paper industry; biomass; fossil fuel; renewable fuel; infrastructure; energy
Efforts have been made to develop a simple chemically defined resuspended mycelial system which m... more Efforts have been made to develop a simple chemically defined resuspended mycelial system which may be used for carrying out fundamental studies regarding the mechanism of kojic acid biosynthesis. As a first step, it was found that mycelia grown in yeast extract sucrose (YES) medium and resuspended in YES medium or in 0.2 M phosphate buffer, pH 6.5, supplemented with 20% glucose or sucrose produced kojic acid almost to the same extent as in the case of growth medium. No kojic acid was formed if buffers or media used for resuspension lacked carbohydrate. Intact mycelia preincubated in buffer alone for 7 days and 3-week-old mycelia could still form kojic acid in large amounts if resuspended in buffer containing glucose. The amount of kojic acid produced by the intact mycelia was found to be more than that produced by the disrupted mycelia. In contrast with static resuspension studies, when Aspergillus flavus mycelia were resuspended in flasks placed on a rotary shaker, much smaller am...
Eight strains of Kluyveromyces marxianus were screened, and all of them were found to ferment the... more Eight strains of Kluyveromyces marxianus were screened, and all of them were found to ferment the aldopentose d -xylose directly to ethanol under aerobic conditions. One of these strains, K. marxianus SUB-80-S, was grown in a medium containing 20 g of d -xylose per liter, and the following results were obtained: maximum ethanol concentration, 5.6 g/liter; ethanol yield, 0.28 g of ethanol per g of d -xylose (55% of theoretical); maximum specific growth rate, 0.12 h −1 ; 100% d -xylose utilization was completed in 48 h.
Recovery of lignin from different processes—kraft process, steam explosion process, organosolv pr... more Recovery of lignin from different processes—kraft process, steam explosion process, organosolv process—is discussed in this chapter. Commercial suppliers of lignin are also listed.
Résumé/Abstract Several yeast strains were tested for their ethanol-producing ability, and one of... more Résumé/Abstract Several yeast strains were tested for their ethanol-producing ability, and one of the most promising was selected for ethanol production in high concentrations. The yeast cells were immobilized in calcium alginate gel beads and were stabilized by ...
Hexokinase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glucose dehydrog... more Hexokinase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glucose dehydrogenase, glucose oxidase and gluconate dehydrogenase have been demon-strated in mycelial homogenates from a strain of Aspergillus JEavus that produces considerable ...
Some recovered paper is utilised outside the paper industry for construction purposes, insulation... more Some recovered paper is utilised outside the paper industry for construction purposes, insulation, mailing bags and other end uses. In most of the countries, no accurate data is available to estimate recovered paper utilisation for applications other than the paper industry. In addition to use in the paper industry, over 8% of collected paper is used in other applications: construction materials, animal beddings, composting and energy. Recycling is considered better than composting in the hierarchy of materials management. In this chapter, uses of recovered paper other than papermaking are discussed.
Alkali treatment of corn stover improves the availability of cellulose and hemicellulose for enzy... more Alkali treatment of corn stover improves the availability of cellulose and hemicellulose for enzymatic attack. Treatments were carried out for 1 to 60 min at temperatures and NaOH concentrations ranging from 100 to 150 degrees C and 0 to 2%, respectively. Solubilization of the stover and sugar production by enzymatic hydrolysis (Trichoderma viride cellulase) of the solid residue and the
Use of biotechnology in pulp bleaching has attracted considerable attention and achieved interest... more Use of biotechnology in pulp bleaching has attracted considerable attention and achieved interesting results in recent years. Enzymes of the hemicellulolytic type, particularly xylan-attacking enzymes, xylanases are now used commercially in the mills for pulp treatment and subsequent incorporation into bleach sequences. The aims of the enzymatic treatment depend on the actual mill conditions and may be related to environmental demands, reduction of chemical costs or maintenance or even improvement of product quality. The use of oxidative enzymes from white-rot fungi, that can directly attack lignin, is a second-generation approach, which could produce larger chemical savings than xylanase but has not yet been developed to the full scale. It is being studied in several laboratories in Canada, Japan, the U.S.A. and Europe. Certain white-rot fungi can delignify kraft pulps increasing their brightness and their responsiveness to brightening with chemicals. The fungal treatments are too slow but the enzyme manganese peroxidase and laccase can also delignify pulps and enzymatic processes are likely to be easier to optimize and apply than the fungal treatments. Development work on laccase and manganese peroxidase continues. This article presents an overview of developments in the application of hemicellulase enzymes, lignin-oxidizing enzymes and white-rot fungi in bleaching of chemical pulps. The basic enzymology involved and the present knowledge of the mechanisms of the action of enzymes as well as the practical results and advantages obtained on the laboratory and industrial scale are discussed.
Flocculent cells of Kluyveromyces marxianus SM 16-10 were used for batch production of ethanol fr... more Flocculent cells of Kluyveromyces marxianus SM 16-10 were used for batch production of ethanol from the inulin sugars derived from Jeru-salem artichoke tubers. Using 20% initial sugar concentration, a maximum ethanol concentration of 92 g/l was achieved in 7 h, when the flocculent cell concentration was 30 g dry wt./l bioreactor volume. The same flocculent cells were used repeatedly for 7 batch runs starting with fresh medium at the beginning of each run. The ethanol yield was found to be almost constant at about 94% of the theoretical for all the 7 batch cycles, while the maximum ethanol production rate increased from 17.21 g ethanol/I/h during the first batch run to 21 g ethanol/i/h during the last batch run.
The growing interest in the application of arachidonic acid (ARA) in various fields of health and... more The growing interest in the application of arachidonic acid (ARA) in various fields of health and dietary requirements has elicited much attention on the industrial production of ARA-containing oil by the cultivation of Mortierella fungi. For the industrial production of ARA, various studies, such as isolation of a high-potential strain and optimization of culture conditions, have been conducted. Studies i ncluding the investigation of morphology are important because ARA is accumulated in the mycelia, and thus cultivation with high biomass concentration is essential for obtaining a high ARA yield. Combining the results derived from various studies, a high ARA yield was attained in an industrial fermentor. These ARA production techniques are applicable to the production of other polyunsaturated fatty acids (PUFAs), and will contribute to the improvement of fermentation technology especially in the field of fungal cult ivation.
There is a significant opportunity now for investors to build, own, and operate biorefineries at ... more There is a significant opportunity now for investors to build, own, and operate biorefineries at existing pulp and paper sites that will work synergistically and economically for the pulp and paper mill owner and the biorefinery owner. The pulp and paper industry is the world’s largest nonfood biomass collection system. The pulp and paper industry is a mature industry producing low-margin commodity products. But it has the ideal infrastructure, experience, and resources to capitalize on the strategic interest in renewable fuels via the biorefinery. Industry leaders, investors, policy-makers, and others are now beginning to better understand the vital role to be played by biorefineries as we move from a fossil fuel-based energy economy toward a bio-based one. When properly located and operated, the potential of an integrated forest biorefinery is expected to be huge: a very attractive and synergistic business opportunity for both the colocated pulp and paper mill and the biorefinery itself. Biorefineries are a key pathway to our biofuture, displacing fossil fuels and supplying clean, renewable, and carbon neutral energy. Biorefineries fit very well at pulp and paper mills because of their inherent ability to gather and process biomass and create energy from biomass.KeywordsBiorefinery; pulp and paper industry; biomass; fossil fuel; renewable fuel; infrastructure; energy
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