• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.297-302
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• 1999

Simultaneous saccharification and fermentation (SSF) experiments were carried out with a lignocellulosic biomass. The effects of temperature on enzymatic saccharification and the ethanol fermentation were also investigated. The batch SSF process gave a final ethanol concentration of 10.44 g/l and equivalent glucose yield of 0.55 g/g, which was increased by 67％ or higher over the saccharification at 42℃. The optimal operating condition was found to vary in several parameters, such as the transmembrane pressure, permeation rate, and separation coefficient, related to the SSF combined with membrane system (semi-batch system). When the fermentation was operated in a semi-batch mode, the efficiency of the enzymes and yeast lasted three times longer than in a batch mode.

• Journal of Applied Biological Chemistry
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• v.63 no.3
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• pp.197-201
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• 2020

In order to enhance the extraction efficiency of flavonoid from Saururus chinensis, carbohydrate-hydrolyzing enzyme Viscozyme L aided extraction techniques have been studied. Then flavonoid composition, as well as quercetin, were also identified using UV/Vis, HPLC/MS, and ¹H-NMR. The results showed that favorable extraction conditions were Viscozyme L concentration of 0.25 mg/g, pH 4.2, reaction at 45 ℃ for 12 h. Under the favorable extraction condition, total flavonoid yield (37.9 mg/g) and quercetin yield (0.86 mg/g) increased by about 2.0 and 9.6 times, respectively, compared to control group. Interestingly, as a significant flavonoid of S. chinensis, flavonoid glycones rutin was hydrolyzed to aglycones quercetin by Viscozyme L. These findings provide scientific and theoretical support for the development quercetin-rich products, which was quickly absorbed by the human body than rutin.

• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.889-892
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• 2010

We investigated a potential for glucose production from cellulose material using two kinds of hyperthermophilic enzymes, endocellulase (EG) and beta-glucosidase (BGL). Two BGLs, from hyperthermophile Pyrococcus furiosus and mesophile Aspergillus aculeatus, were compared with P. horikoshii endocellulase (EGPh) for complete hydrolysis of cellulose. The combination reactions by each BGL enzyme and EGPh could produce only glucose without the other oligosaccharides from phosphoric acid swollen Avicel (PSA). The combination of both the hyperthermophilic cellulases, BGLPf and EGPh, will be adaptable to a high efficiency system to produce glucose at high temperature.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1568-1572
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• 2010

The selective isolation of specific proteins from complex protein mixtures by nanoparticles is reported. Glutathionemodified superparamagnetic nanoparticles were used to purify specific proteins fused with glutathione S-transferase via enzyme-substrate interactions. They demonstrated greatly improved selectivity and efficiency over micron sized capturing beads. The ultra-specific enrichment of target proteins was confirmed by both SDS-PAGE and LC/MS/MS experiments.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.3
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• pp.147-150
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• 2004

Permeabilization is known to overcome cell membrane barriers of whole cell biocatalysts. The use of organic solvents is advantageous in terms of cost, simplicity, and efficiency. In this study, Ochrobactrum anthropi SY509 was permeabilized with various organic solvents. Treatment with organic solvents resulted in lower permeability barriers due to falling out lipids of the cell membrane. Therefore, permeabilized cells showed higher enzyme activity with no cell viability. Among various organic solvents, 0.5% (v/v) chloroform was selected as the most efficient permeabilizing reagent. Changes in the cell membrane structure were observe d and the residual amounts of phospholipids of the cell membrane were measured to investigate the mechanism of the improved permeability.

• Biomedical Science Letters
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• v.18 no.1
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• pp.29-34
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• 2012

Streptomycetes are gram-positive filamentous bacteria that are well-known for producing a vast array of bioactive compounds, including more than 70 % of commercially important antibiotics. For the research about Streptomyces sp., the protoplast and electroporation transformation method have been the general techniques for the construction of transformants. However, these techniques have low efficiency and are time-consuming. Another option is intergenic conjugation, which is used for DNA transfer using methylation-deficient E. coli as a DNA donor to avoid the methylated-DNA-dependent restriction systems of actinomycetes. This conjugation method has been widely improved and applied to many other actinomycetes. In this research, an effective transformation procedure for the construction of expression vector by using gateway system was established to avoid limit of restriction enzyme site for cloning of target gene based on transconjugation by Escherichia coli ET12567/pUZ8002 with a pSET152 integration vector.

• Proceedings of the Microbiological Society of Korea Conference
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• 2000.10a
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• pp.85-91
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• 2000

Aspergillus oryzae is a filamentous fungus classified in the group Aspergillaceae Ascomycetes. It is an important microorganism for industrial production of enzymes and fermented food productions. It secrets large quantities of proteins or enzymes into the culture medium which makes this organism appealing for the production of heterologous proteins. Recently Electric field-mediated transformation method, electroporation, has been applied to fungal transformation. In this study, fungal transformation was carried out by bypassing the protoplast isolation step, decreasing the culturing time and non-protoplast transformation for the increment of transformation efficiency. Transformants were obtained with electroporation in optimal condition 2,500 voltage, 1,540 ohm and 0.50 capacitance. More than 1,000 transform ants were obtained with 6-10 hrs cultured mycelia without enzyme treatment, called non-protoplast transformation.

• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.505-510
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• 2006

A gallocyanine-bound nanoporous titanium dioxide electrode system was investigated to carry out a mediated enzyme reaction. Gallocyanine was bound either directly or through an aminopropylsilane linker to the film of nanoporous titanium dioxide and used as a mediator for nitrate reductase in the mediated enzymatic nitrate reduction. The electrode with the aminopropylsilane linker showed 20% higher efficiency of electron transfer at the same potential than that directly linked. The prepared electrodes showed $0.26{\mu}mol/h$ nitrate reduction at a $100mm^2$ surface of the electrode, and linear current response on nitrate ion concentration up to 1.0 mM, which is very useful as a biosensor of nitrate ion in water.

• Current Research on Agriculture and Life Sciences
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• v.22
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• pp.49-56
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• 2004

Cellulolytic enzymes were prepared from alkaline resistant microorganisms which were newly screened from calcic soil. Characteristics of enzymes and enzymatic deinking efficiency of wastepaper were investigated. The results were summarized as fellows: 1. The recovery rate of crude enzyme was 93.7% in Bio-B and 57.4% in Bio-F. 2. The protein content in crude enzymes was lowest and the thermal stability of crude enzymes was highest in Bio-F. 3. The brightness gain of Bio-F deinked pulp was best in ONP and Bio-B deinked pulp was best in MOW. 4. The reject yield was increased with enzymatic deinking flotation process. 5. The residual ink area of paper was increased with enzymatic deinking and large size of ink particles were remained in paper.

• Proceedings of the Korean Biophysical Society Conference
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• 1997.07a
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• pp.37-37
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• 1997

The catalytic efficiency of pyranose oxidase (EC 1.1.3.10.) determined for various sugars showed that D-glucose is the preferred substrate and the enzyme oxidized the various aldonolactones. The specificity constants of pyranose oxidase determined for deoxy- and deoxyfluoro-D-glucoses showed that a hydroxy group at C-4 of D-glucose acts as a hydrogen-bone acceptor, at C-6 as a hydrogen-bond donor, and at C-1 as a hydrogen-bond donor.(omitted)