• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.368-376
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• 2003

Cyclodextrin glucanotransferase (CGTase) from Paenibacillus sp. JB-13 was immobilized on various carriers by several immobilization methods such as ionic binding, covalent linkage and ultrafiltration to improve the process performance. The ultrafiltration and covalent linkage with CNBr-activated sepharose 4B were found as the best method for immobilization of CGTase. The ability of CGTase immobilization onto CNBr-activated sepharose 4B was as high as 18,000 units/g resin when the conditions was as follows: contact time 9 hrs at $37^{\circ}C$, pH 6.0, 100 nm and enzyme loading 24,000 units/g resin. The optimum conditions for production of 2-O-$\alpha$-D-Glucopyranosyl L-Ascorbic acid by immobilized CGTase turned out to be: pH 5.0, temperature $37^{\circ}C$, 20% substrate solution containing 8% (w/v) of soluble starch and 12% (w/v) of L-ascorbic acid sodium salt, 100 rpm, far 25 hrs and with 800 units of immobilized CGTase/ml substrate solution. Moreover the CGTase activity could be stably maintained for 8 times of repetitive reactions after removing products by ultrafiltration through YM 10 membrane.

• Resources Recycling
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• v.29 no.3
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• pp.51-60
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• 2020

This study was carried out to get the optimum conditions for manufacturing high refractive glass beads from waste fluorescent lamp glass. Chemical composition, X-ray diffraction pattern, particle size distribution, refractive index of glass beads, and the effect of air mixing ratio and ejection rate were investigated. The obtained results are as follows. The X-ray diffraction pattern and chemical composition of glass beads made of waste fluorescent glass are similar to common glass except ReO₂ 0.0108 wt%, BaO 0.071 wt%, NiO 0.0039 wt% and CaO 7.8 wt% but 11.7 wt% of common glass. The glass beads made of waste fluorescent lamp glass have the narrower particle size distribution of and the higher refractive index than the glass beads made of common glass. The optimal conditions of kiln operation for manufacturing glass beads from waste fluorescent lamp glass are 20 m/sec of ejection rate, 1.7 of air mixing ratio, and 940℃ of temperature.

• The Transactions of the Korea Information Processing Society
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• v.7 no.2
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• pp.385-391
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• 2000

Recently, neural network research for forecasting the consecutive controlling rules of the future is being progressed, using the series data which are different from the traditional statistical analysis methods. In this paper, we suggest the pruning algorithm for the fast and exact weather forecast that excludes the hidden layer of the early optional designed nenral network. There are perform the weather forecast experiments using the 22080 kinds of weather data gathered from 1987 to 1996 for proving the efficiency of this suggested algorithm. Through the experiments, the early optional composed $26{\times}50{\times}1$ nenral network became the most suitable $26{\times}2{\times}1$ structure through the pruning algorithm suggested, in the optimum neural network $26{\times}2{\times}1$, in the case of the error temperature ${\pm}0.5^{\circ}C$, the average was 33.55%, in the case of ${\pm}1^{\circ}C$, the average was 61.57%, they showed more superior than the average 29.31% and 54.47% of the optional designed structure, also. we can reduce the calculation frequency more than maximum 25 times as compared with the optional sturcture neural network in the calculation frequencies.

• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.314-321
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• 2015

Agar-hydrolyzing bacteria were isolated from the coastal sea water of Jeju Island. One isolate, designated as S4, was selected for further study. The S4 cells were Gram-negative and rod-shaped with smooth beige surfaces and single polar flagellum. Cells were grown at $15-42^{\circ}C$, 0.5-5% (w/v) NaCl, between pH 6.0 and 9.0, and in media containing 0.5-5% (w/v) NaCl. The G+C content was 49.93 mol%. The major fatty acids (>15%) were $C_{18:1}{\omega}7c$, $C_{16:0}$ and Summed feature 3 (comprising $C_{16:1}{\omega}7c/iso-C_{15:0}$ 2-OH). Based on 16S rRNA sequencing and biochemical and chemotaxonomic characteristics, the strain was designated as Vibrio sp. S4. In liquid culture supplemented with 0.1% agar the cell density and agarase activity reached a maximum level in 72 h, while agarase activity in the culture without agar was negligible, implying agarose expression is induced by agar. The optimum pH and temperature for the extracellular crude agarase of S4 were 7.0 and $45^{\circ}C$, respectively. However, it also exhibited 98.6% and 87.6% at $40^{\circ}C$ and $50^{\circ}C$, respectively, of the maximum activity seen at $45^{\circ}C$. The crude agarase hydrolyzed agarose into (neo)agarotetraose and (neo)agarohexaose.

• Microbiology and Biotechnology Letters
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• v.48 no.2
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• pp.158-166
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• 2020

A gene coding for the xylanase was cloned from Paenibacillus woosongensis, followed by determination of its complete nucleotide sequence. This xylanase gene, designated as xyn10A, consists of 1,446 nucleotides encoding a polypeptide of 481 amino acid residues. Based on the deduced amino acid sequence, Xyn10A was identified to be a modular enzyme composed of a catalytic domain highly homologous to the glycosyl hydrolase family 10 xylanase and a putative carbohydrate-binding module (CBM) in the C-terminus. By using DEAE-sepharose and phenyl-sepharose column chromatography, Xyn10A was purified from the cellfree extract of recombinant Escherichia coli carrying a P. woosongensis xyn10A gene. The N-terminal amino acid sequence of the purified Xyn10A was identified to exactly match the sequence immediately following the signal peptide predicted by the Signal5.0 server. The purified Xyn10A was a truncated protein of 33 kDa, suggesting the deletion of CBM in the C-terminus by intracellular hydrolysis. The purified enzyme had an optimum pH and temperature of 6.0 and 55-60℃, respectively, with the kinetic parameters V_max and K_m of 298.8 U/mg and 2.47 mg/ml, respectively, for oat spelt xylan. The enzyme was more active on arabinoxylan than on oat spelt xylan and birchood xylan with low activity for p-nitrophenyl-β-xylopyranoside. Xylanase activity was significantly inhibited by 5 mM Cu²⁺, Mn²⁺, and SDS, and was noticeably enhanced by K⁺, Ni²⁺, and Ca²⁺. The enzyme could hydrolyze xylooligosaccharides larger than xylobiose. The predominant products resulting from xylooligosaccharide hydrolysis were xylobiose and xylose.

• Textile Coloration and Finishing
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• v.32 no.1
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• pp.9-18
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• 2020

In this study, we conducted alkali hydrolysis on sea-island type PET ultramicrofiber tricot fabric and dyeing according to the various conditions with black disperse dye. Herein, we evaluated the weight loss rate and tensile strength according to the NaOH contents. The optimal alkali hydrolysis treatment conditions were set to 25 %omf NaOH with a treatment time of 60 min at 110 ℃, and average weight loss rate of the PET ultramicrofiber tricot fabric is about 23 %. The dyeing conditions were investigated with different dyeing temperatures(95-135 ℃), dyeing time(20-60 min), dye contents(2-10 %omf), dispersant contents(1-9 g/ℓ), pH buffer solution contents(1-9 g/ℓ), UV-absorbent contents(5-25 %omf) and reduction cleaning process conditions for black color. We obtained the optimum conditions of the dyeing with the dye contents of 8 %omf, the dispersant contents of 1 g/ℓ, the pH buffer solution contents of 1 g/ℓ, the UV-absorbent contents of 10 %omf, the dyeing temperature of 135 ℃ and the dyeing time of 40 min. The light colorfastness of dyed ultramicrofiber PET tricot fabric was good to excellent in the range of 4 to 5.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.147-156
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• 2014

The aim of this study was to investigate the physiological characteristics and anti-obesity effects of E. faecalis MD366 isolated from raw milk. E. faecalis MD366 inhibited lipase activity ($65.0{\pm}0.9%$) and differentiation of 3T3-L1 adipocytes ($27.4{\pm}1.4%$) at a concentration of $100{\mu}g/mL$ ($10^8CFU/g$ E. faecalis MD366). The optimum growth temperature of E. faecalis MD366 was $37^{\circ}C$. Among 16 tested antibiotics, E. faecalis MD366 demonstrated the highest sensitivity to novobiocin and the highest resistance to neomycin, kanamycin, and vancomycin. The strain also showed high acid phosphatase activity. Moreover, E. faecalis was relatively tolerant to bile juice and acid, and displayed high resistance to Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus (80.4%, 60.2%, and 65.4%, respectively). These results demonstrate that E. faecalis MD366 can be potentially used as a probiotic with anti-obesity effects.

• Resources Recycling
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• v.14 no.6 s.68
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• pp.28-36
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• 2005

A hydrometallurgical process to leach cobalt from the waste cathodic active material, $LiCoO_{2}$, and subsequently to separate it by solvent extraction was developed. The optimum leaching conditions for high recovery of colbalt and lithium were obtained: 2.0 M sulfuric acid, 5 $vol.\%$ hydrogen peroxide, $75^{\circ}C$ leaching temperature, 30 minutes leaching time and an initial pulp density of 100 g/L. The respective leaching efficiencies for Co and Li were $93\%$ and $94.5\%$. About $85\%$ Co was extracted from the sulfuric acid leach liquor containing 44.72 g/L Co and 5.43 g/L Li, using 1.5 M Cyanex272 as an extractant at the initial pH 5.0 and in organic to aqueous phase ratio of 1.6:1 under the single stage extraction conditions. The Co in the raraffinate was completely extracted by 0.5 M Na-Cyanex272 at the inital pH 5.0, and an organic to aqueous phase ratio of 1;1. The cobalt sulfate solution of higher than $99.99\%$ purity could be recovered from waste $LiCoO_{2}$, using a series of hydrometallurgical processes: sulfuric acid leaching of waste $LiCoO_{2}$- solvent extraction of Co by Na-Cyanex 271 - scrubbing of Li by sodium carbonate solution - stripping of Co by sulfuric acid solution.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.384-388
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• 1996

This research was conducted to investigate the effective methods for browning inhibition on yam (Dioscorea aimadeimo) during dehydration by physical and chemical pretreatments. Moisture, crude protein, crude fiber and N-free extract contents of yam were 81.17%, 1.43%, 0.29% and 15.81%, respectively. Yams were sliced to 0.5 cm thickness and placed to single and poly layer in plastic tray, and then changes of their weights were measured during air dehydration at $50^{\circ}C,\;65^{\circ}C,\;and\;80^{\circ}C$. The dehydration time reaching to optimum moisture level for the pulverization of the yam slices were 10, 6, 3 hours(single layered) and 12, 7, 5 hours(multi layered) at the respective temperature. To inhibit browning at $80^{\circ}C$ air dehydration, water and steam blanching, microwave treatment effects were investigated on yam slices for 30 sec. and 60 sec. Steam blanching for 30 sec. was comparatively effective to inhibit browning of yam slices. Yam slices were immersed in single and combined browning inhibitor solutions and evaluated for browing degree during dehydration by the values of Hunter L, a, b and ${\Delta}E$. The most effective pretreatment to inhibit browning of yam slices was immersion In the solution containing 500 ppm of citric acid and 1000 ppm of cysteine for 1 min.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.333-337
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• 1996

For continuous production of galactooligosaccharides(GOS), $\beta-galactosidase$ with h1gh transgalactosylation activity from Bacillus sp. A 4442 was Immobilized onto $Diaion^{TM}$ HPA 75(styrene-divinylbenzene resin). The parameters influencing enzyme immobilization were scrutinized in order to maximize immobilization yield while minimizing enzyme inactivation. The optimum conditions turned out to be: Tris buffer concentration 30 mM, pH 8.0, contact time at room temperature 3 hr, and enzyme loading 25 mg protein/g resin. Both the thermal stability and the operational stability of immobilized enzyme were markedly enchanced by the treatment with 0.5% glutaraldehyde as a cross-linker. Under the experimental conditions established, the yield of ${\beta}-galactosidase$ immobilization was 40% or more and the activity of the immobilized enzyme ca. 200 U/g resin. When a packed-bed reactor was employed to continuously convert lactose to GOS, the specific production, which refers to as the amount of commercially valuable GOS produced by a unit amount of immobilized ${\beta}-galactosidase$, was found to be ca. 300 g GOS/g carrier.