• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.335-340
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• 2016

This study was conducted to find out the most suitable DNA isolation methods for PCR detection of foodborne pathogens. Four DNA isolation methods including Universal Genomic DNA Extraction Kit (TaKaRa), PrepMan Ultra (Applied Biosystems), boiling method and alkaline lysis method (w/PEG) were tested and compared. The Universal Genomic DNA Extraction kit (TaKaRa) was considered as the more efficient isolation method for Escherichia coli O157:H7 and Staphylococcus aureus in lettuce, fish and beef. Meanwhile to detect the foodborne pathogens directly from foods without enrichment, the four different buffers such as double-distilled water, saline, glycine-saline, glycine-saline with Tween-20 and beef extract were also evaluated. As a result, saline was more suitable buffer for E. coli O157:H7. And double-distilled water was more suitable buffer than saline for S. aureus, respectively

• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2051-2059
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• 2016

To date, there has been no employment of a magnetoelastic (ME) biosensor method to detect Salmonella enterica serovar Typhimurium in soil. The ME biosensor method needs to be investigated and modified for its successful performance. The filtration method, cation-exchange resin method, and combinations of both methods were employed for the extraction of S. Typhimurium from soil. The number of S. Typhimurium and the resonant frequency shift of the ME sensor were then compared using a brilliant green sulfa agar plate and an HP 8751A network analyzer. A blocking study was performed using bovine serum albumin (BSA), polyethylene glycol (PEG), and casein powder suspension. Finally, the modified ME biosensor method was performed to detect S. Typhimurium in soil. The number of S. Typhimurium was significantly decreased from 7.10 log CFU/soil to 4.45-4.72 log CFU/soil after introduction of the cation-exchange resin method. The greatest resonant frequency shift of the measurement sensor was found when employing centrifugation and filtration procedures. The resonant frequency shift of the PEG-blocked measurement sensor was $3,219{\pm}755Hz$, which was significantly greater than those of the BSA- and casein-blocked ME sensor. The optimum concentration of PEG was determined to be 1.0 mg/ml after considering the resonant shift and economic issue. Finally, the modified ME biosensor method was able to detect S. Typhimurium in soil in a dose-response manner. Although these modifications of the ME biosensor method sacrificed some advantages, such as cost, time effectiveness, and operator friendliness, this study demonstrated a novel approach of the ME biosensor method to detect S. Typhimurium in soil.

• Journal of Periodontal and Implant Science
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• v.27 no.3
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• pp.443-457
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• 1997

The purpose of this study was to evaluate the effects of ethanolic extracts of Scutellaria Radix on the alveolar bone formation in the extract socket of rat. Thirty-six Sprague-dawley rats were used in this study. Mean body weight of rat was $130{\pm}5g$. Experimental animal were administered 0.4% ,${\beta}-aminopropionitril$(Sigma, USA) with the solid commercial food for 5 days. All the maxillary 1st molar of the rats were extracted by using of the tissue forcep under the general anesthesia with Pentobarbital sodium(Tokyo Chemical Co, Japan) injection into intraperitoneal space. All the extracted rats were divided into two group, experimental group which were feeded the solid food mixed ethanolic extracts of Scutellaria Radix, and control group which were feeded same food without reagent. At 1, 3, 5, 7, 9 and 14th days after tooth extraction, rats in both groups were serially sacrificed respectively. All the specimen were treated as usual method and prepared Hematoxylin-eosin stain for the light microscopic observation. The results were as follows : 1. Bone formation of extracted socket starts from the area on remained periodontal ligament than other area. 2. In the case of administration of the extracted Scutellaria Radix showed rapid healing process of connective tissue than non-administrated group. 3. In the case of administration of the extracted Scutellaria Radixshowed rapid osteogenesis than non-administrated With above results, it was concluded that ethanolic extracts of Scutellaria Radix may play a favorable role on the healing process of exatraction socket after extraction in rats. It was suggested that further study to evaluate the different concentration and administration method of ethanolic extracts of the Scutellaria Radix into same experimental model.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.977-983
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• 2002

This study was performed to establish the precise and rapid method to distinguish croakers through the pigment analysis of colored imported white croakers for adultration. We surveyed the coloring behaviors, extraction test by water and organic solvent and using pigments such as targeting, curcumine, and azo dye products. The pigment of yellow croaker is not stained on wet cloth or tissue which is rubbed on epidermis of yellow croaker and was not eluted in water extraction test, while adulterated pigments were easily extracted by water and acetone, but edible diluted yellow, Yellow No. 4 and Yellow No. 5 were not extracted. Reactive pigment was detected easily by extraction with water and dispersed pigment was also detected by extraction test. As a result of discoloring characteristics of carotene having similar structure to yellow croaker and azo dye by oxidation and reduction, azo dyes were not discolored by oxidation with sodium percarbonate or peracetic acid but that were discolored by oxidation with Fenton reagent after 1hr and by hypochlorite promptly. On the other hand, carotenes were not discolored by sodium precarbonate and Fenton reagent but discolored by sodium hypochlorite after 2 hr and by peracetic acid promptly. Azo dyes were discolored by reduction with sodium hydrosulfite and sodium carbonate but carotenes were not discolored by these reagents. This discoloring test was applicable to detect adulterated pigments and other marine product.

• Resources Recycling
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• v.29 no.2
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• pp.62-68
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• 2020

In new millennium, wide-reaching demands for selective catalytic reduction (SCR) catalyst have been increased gradually in new millennium. SCR catalyst can prevent the NO_x emission to protect the environment. In SCR catalyst the main composition of the catalyst is typically TiO₂ (70~80%), WO₃ (7~10%), V₂O₅ (~1%) and others. When the SCR catalysts are used up and disposed to landfills, it is problematic that those should exist in the landfill site permanently due to their extremely low degradability. A new advanced technology needs to be developed primarily to protect environment and then recover the valuable metals. Hydrometallurgical techniques such as leaching and liquid-liquid extraction was designed and developed for the spent SCR catalyst processing. In a first stage, V and W selectively leached from spent SCR catalyst, then both the metals were processed by liquid-liquid extraction process. Various commercial extractants such as D2EHPA, PC 88A, TBP, Cyanex 272, Aliquat 336 were tested for selective extraction of title metals. Scrubbing and stripping studies were tested and optimized for vanadium and tungsten extraction and possible separation. 3^rd phase studies were optimized by using iso-decanol reagent.

• Resources Recycling
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• v.25 no.6
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• pp.50-57
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• 2016

This work was examined the extraction and stripping behavior of rare earths (La, Ce, Pr, Nd, Sm) from the hydrochloric acid solution by Cyanex 572 and compared to the results that of PC88A. Experimental parameters such as equilibrium pH, extractant & strip reagent concentration were observed and extraction percentage, distribution coefficient, stripping percentage and the separation factor of the adjacent element were analyzed. The $pH_{50}$ values was more higher using Cyanex 572 than that of PC88A. As the increase of the extractant concentration, the distribution coefficient of rare earth elements was increased. Stripping percentage of rare earth elementss from the Cyanex 572 was 85% to 95% and PC88A showed 80% to 87%. Separation factor of Ce/La, Ce/Pr, Pr/Nd, Nd/Sm was enhanced about 1.0-5.0 using Cyanex 572 as an extractant in mixture solution.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.5
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• pp.323-326
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• 2002

To detect whole ammonia-oxidizing bacteria in the activated sludge, group-specific primers targeting the 16S-rRNA gene of ammonia-oxidizing bacteria were used. The electrophoresis pattern of the PCR products seemed to produce a single band of approximately 1.0 k bp for the bacteria in activated sludge and Nitrosomonas europaea. No band was observed for nitrite-oxidizer Nitrobacter winogradskyi and heterotrophs such as Pseudomonas putida. Then direct measurement of the PCR product was made by fluorometry using the reagent Hoechist 33258, so that the fluorescent intensity was in proportional to the cell number of the sample up to 240. Total time required for the test was about 4 h including DNA extraction. The DNA fragments produced were cloned and their sequences showed high similarity to those of Nitrosomonas spp. This study showed the feasibility to detect ammonia-oxidizing bacteria and to esti-mate their population rapidly for the control of the nitrogen elimination process.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.100-105
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• 2017

Various methods for assessing soil total nitrogen (TN) and inorganic N content have been developed to manage nutrient and to understand N cycle in soil. This paper address the technical procedures in arable soil samples to conduct soil sampling, sample preparation, and measuring total N and inorganic N. Among various methods for measuring soil total nitrogen contents, Kjeldahl distillation and Indophenol blue method have widely used due to reliability and economic advances. Also, two methods can analyze more samples at the same time compared with other nitrogen measuring methods. For evaluating inorganic N content, mainly in forms of nitrate-N ($NO_3{^-}-N$) and ammonium-N ($NH_4{^+}-N$), extraction with a single reagent such as 2M KCl has been employed, followed by Kjeldahl distillation or indophenol blue methods.

• Korean Journal of Veterinary Research
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• v.33 no.1
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• pp.61-69
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• 1993

In order to search for new antibiotics from anaerobic bacteria, a large number of samples from domestic soil were collected and processed by apropriate methods. A potential strain, Streptococcus sp. An-21-1, was found to produce antimicrobial compounds. The Results were as follows; 1. During fermentation, the bacteria grew rapidly up to 20hr, thereafter entered the death phase. The optimal temperature and pH for the bacterial growth were $37^{\circ}C$ and pH 7.0, respectively. 2. Antibiotics were purified from culture broth by solvent extraction, silica gel column chromatography and Sepadex L.H 20 column. 3. Physicochemical properties of Ap-1 and Ap-2 were similar ; Their melting points were between $234-237^{\circ}C$. Color reactions of ninhydrin, 2,7-dichlorofluorescein, 4-dimethylaminobenzaldehyde, Dragendroffs reagent and 20% $H_2SO_4$, were positive. Therefore, we assumed that these antibiotics have amine group, immine group, alkaloid, and lipid components. These were stable to heat. UV spectrophotometry showed two peaks at 210 nm and 260 nm. From above results, we assumed these antibiotics are belong to the peptide antibiotic family.

• Analytical Science and Technology
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• v.16 no.6
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• pp.458-465
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• 2003

The HS (headspace)-SPME (Solid phase microextraction) as rapid and simple method was performed for the determination of volatile fatty acids (VFAs) from the aqueous samples. In-fiber derivatization of VFAs with 1-Pyrenyldiazomethane (PDAM) was applied to improve their sensitivity of detection. In SPME procedure, typical parameters such as effects of solution pH, and salting out reagent and ultrasonication were investigated to improve the extraction efficiency. Based on the developed method, VFAs in wastewater samples were determined by gas chromatography / mass spectrometry-selected ion monitoring (GC/MS-SIM) mode.