• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.401-404
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• 2015

Bacillus coagulans has been considered to be a prominent candidate for probiotics as well as a thermotolerant biomaterial producer. However, the species has not attracted the attention of Korean researchers, nor has it been commercialized in Korea. Therefore, isolates for functional studies are not readily available. To secure B. coagulans resources for future applications, we developed a rapid isolation method for the species from rice straw. Introduction of the enrichment culture at $50^{\circ}C$, the selection of acid producers with $CaCO_3$ supplemented medium, and the elimination of enterococci by selective medium, rendered the successful and rapid isolation of B. coagulans strains.

• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.545-548
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• 2004

A sensitive, selective and rapid method for the determination of nickel based on the rapid reaction of nickel(II) with QADMAA and the solid phase extraction of the Ni(II)-QADMAA chelate with $C_{18}$ membrane disks has been developed. In the presence of pH 6.0 buffer solution and sodium dodecyl sulfonate (SDS) medium, QADMAA reacts with nickel to form a violet complex of a molar ratio of 1 : 2 (nickel to QADMAA). This chelate was enriched by solid phase extraction with $C_{18}$ membrane disks. An enrichment factor of 50 was obtained by elution of the chelates form the disks with the minimal amount of isopentyl alcohol. The molar absorptivity of the chelate was $1.32{\times}10^5L\;mol^{-1}cm^{- 1}$ at 590 nm in the measured solution. Beer's law was obeyed in the range of 0.01-0.6 ${\mu}$g/mL. This method was applied to the determination of nickel in water and biological samples with good results.

• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.549-552
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• 2004

A sensitive, selective and rapid method has been developed for the determination of mercury based on the rapid reaction of mercury(II) with p-sulfobenzylidenethiorhodanine (SBDTR) and the solid phase extraction of the colored chelate with $C_{18}$ disks. In the presence of pH 3.5 sodium acetate-acetic acid buffer solution and Emulsifier-OP medium, SBDTR reacts with mercury(II) to form a red chelate of a molar ratio 1 : 2 (mercury to SBDTR). This chelate was prconcentrated by solid phase extraction with $C_{18}$ disks. An enrichment factor of 50 was achieved. The molar absorptivity of the chelate is $1.28{\times}10^5 L{\cdot}mol^{-1}{\cdot}cm^{-1}$ at 545 nm in measured solution. Beer's law is obeyed in the range of 0.01-3 ${\mu}$g/mL. The relative standard deviation for eleven replicates sample of 0.01 ${\mu}$g/mL is 1.65%. This method was applied to the determination of mercury in tobacco and tobacco additive with good results.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.263-266
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• 2004

A sensitive, selective and rapid method has been developed for the determination ${\mu}$g/L level of vanadium ion based on the rapid reaction of vanadium(V) with 2-(2-quinolylazo)-5-diethylaminophenol (QADEAP) and the solid phase extraction of the colored chelate with $C_{18}$ cartridge. The QADEAP reacts with V(V) in the presence of citric acid-sodium hydroxide buffer solution (pH = 3.5) and cetyl trimethylammonium bromide (CTMAB) medium to form a violet chelate of a molar ratio 1 : 2 (V(V) to QADEAP). This chelate was enriched by solid phase extraction with $C_{18}$cartridge and the enrichment factor of 50 was obtained by elution of the chelates from the cartridge with ethanol. The molar absorptivity of the chelate is $1.28 {\times}10^5L\;mol^{-1}cm^{-1}$ at 590 nm in the measured solution. Beer's law is obeyed in the range of 0.01-0.6 ${\mu}$g/mL. The detection limit is 0.04 ${\mu}$g/L in the original samples. This method was applied to the determination of vanadium(V) in water and biological samples with good results.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1301-1305
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• 2006

The development of rapid, infallible, and sensitive methods of detecting foodborne pathogens has received much impetus in recent years owing to an increased public awareness of the health hazards. For the rapid and simultaneous detection of these foodborne pathogens, a multiplex PCR method was developed. Yersinia enterocolitica, Staphylococcus aureus, and Shigella spp. are bacteria of concern because of their specific growing condition that enables them to live at low temperatures. In order to detect each pathogenic bacterium, specific primers from Y. enterocolitica, St. aureus, and Sh. flexneri were selected and validated successfully. To apply this method to food stored at low temperature, Y. enterocolitica, St. aureus, and Sh. flexneri were artificially inoculated in lettuce and incubated for enrichment. The multiplex PCR assays were able to simultaneously detect three pathogens, and the presence of three bands was observed at initial inoculation levels of approximately 1$\times$10$^1$ CFU/g in lettuce. Therefore, this method could be used for simultaneous detection of Y. enterocolitica, St. aureus, and Shigella spp. contaminated in lettuce during cultivation, transportation, preservation, and storage.

• Journal of Biosystems Engineering
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• v.39 no.2
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• pp.115-121
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• 2014

Background: Frequent outbreaks of foodborne illness have been increased awareness of food safety. CDC estimates that each year roughly 48 million people gets sick, 128,000 are hospitalized and 3,000 die of foodborne diseases in US. In Korea, 6,058 were hospitalized and 266 incidents were reported in 2012. It is required to develop rapid methods to identify hazard substances in food products for protecting and maintaining safety of the public health. However, conventional methods for pathogens detection and identification involve prolonged multiple enrichment steps. Purpose: This review aims to provide information on biosensors to detect pathogens in food products to enhance food safety. Results: Foodborne outbreaks continue to occur and outbreaks from various food sources have increased the need for simple, rapid, and sensitive methods to detect foodborne pathogens. Conventional methods for foodborne pathogens detection require tremendous amount of labor and time. Biosensors have drawn attentions in recent years because of their ability to detect analytes sensitively and rapidly. Principles along with their advantages and disadvantages of a variety of food safety biosensors including fiber optic biosensor, impedimetric biosensor, surface Plasmon resonance biosensor, and nano biosensor were explained. Also, future trends for the food safety biosensors were discussed.

• Journal of The Korean Astronomical Society
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• v.18 no.2
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• pp.79-85
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• 1985

From the uvby, $H_{\beta}$ photometry of intermediate population II F-stars in the catalogue of Olsen (1983), we derived age-metallicity relations for these stars, using Hejlesen's (1980) isochrone. The derived age-metallicity relations well coincide with the theoretical predictions by the unclosed two-zone model of Lee and Ann (1981). There are few extremely metal poor F-stars in the vicinity of the Sun, and it is very likely that the initial rapid metal enrichment in the galactic disk might have been processed through the fast collapse of the disk at the very early epoch.

• YAKHAK HOEJI
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• v.32 no.6
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• pp.415-419
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• 1988

A rapid and simple method for the determination of pentoxifylline and its major metabolite, metabolte(I) in plasma was examined by HPLC. For the purification and enrichment of drug from plasma, solid-phase extraction was examined using Sep-pak C18 cartridge. The effectiveness of test method was proved by monitoring of the rat after oral administration of pentoxifylline in a dose of 40mg/kg.

• Journal of Veterinary Science
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• v.21 no.5
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• pp.79.1-79.12
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• 2020

Background: Recently, the pork industry of Thailand faced an epidemic of highly virulent strains of porcine reproductive and respiratory syndrome virus (PRRSV), which spread throughout Southeast Asia, including the Lao People's Democratic Republic and Cambodia. Hence, the rapid and on-site screening of infected pigs on a farm is essential. Objectives: To develop the new aptamer as a biosensor for detection PRRSV which are rapid and on-site screening of infected pig. Methods: New aptamers against PRSSV were identified using the combined techniques of capillary electrophoresis, colorimetric assay by gold nanoparticles, and quartz crystal microbalance (QCM). Results: Thirty-six candidate aptamers of the PRRSV were identified from the systematic evolution of ligands by exponential enrichment (SELEX) by capillary electrophoresis. Only 8 out of 36 aptamers could bind to the PRSSV, as shown in a colorimetric assay. Of the 8 aptamers tested, only the 1F aptamer could bind specifically to the PRSSV when presented with the classical swine fever virus and a pseudo rabies virus. The QCM was used to confirm the specificity and sensitivity of the 1F aptamer with a detection limit of 1.87 × 10¹⁰ particles. Conclusions: SELEX screening of the aptamer equipped with capillary electrophoresis potentially revealed promising candidates for detecting the PRRSV. The 1F aptamer exhibited the highest specificity and selectivity against the PRRSV. These findings suggest that 1F is a promising aptamer for further developing a novel PRRSV rapid detection kit.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.5
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• pp.533-540
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• 2014

The remanufacturing industry for automotive parts is a major issue which affects the environment protection and CO2 reduction throughout the world. Beside this, remanufacturing technologies of worn-out diesel engines have been developing to make as close to new as possible. In this study, the characteristics of the engine-power output and exhaust emissions of remanufactured diesel engine by hydrogen enrichment are evaluated by measuring the engine and vehicle test. Moreover, with worn-out diesel engine and first generation common-rail engine, we compared by testing their characteristics, resulting in the restoration of engine-power output more than 93%, as well as marvelously reduces the THC and NOx emission. At a guess, high pressure injection of diesel increases fuel atomization characteristics with excellence combustion efficiency, resulting in reduction of THC emission. Also, rapid cooling of EGR decreases combustion temperature, resulting in reduction of NOx emission. Consequently, these remanufacturing for diesel engine enables worn-out diesel engine to have restoration to the original state. Simultaneously achieved 2 goals called that CO2 emission reduction and protection of environment by remanufacturing engine.