• Polymer(Korea)
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• v.35 no.3
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• pp.216-222
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• 2011

A multi-walled carbon nanotube (MWNT) support with dual properties, an ionic property via tetra-amine and unpaired electrons via tri-amine, was prepared by radiation-induced graft polymerization of glycidyl methacrylate (GMA) and the subsequent amination of its epoxy group. The electrochemical microbial biosensor (EMB) was then fabricated by immobilization of a microbe (Alkaligenes spp.) onto the dual property-modified electrode, which was prepared with the mixture of the MWNT support and a $Nafion^{(R)}$ solution on a glass carbon (GC) electrode surface by a hand-casting method. The sensing range of the prepared EMB for phenol in a phosphate buffer solution was 0.005~7.0 mM. The total concentration of phenolic compounds in a commercial red wine was also determined using the EMB.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1234-1243
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• 2000

A method for quantitative determination of styrene dimer and trimer, which are suspected as endocrine disruptors, in foods and containers was studied. For residual contents of styrene dimer and trimer in two-kinds of containers, which contained instant noodle and yogurt, sample pieces were completely dissolved in tetrahydrofuran. The polymer was precipitated with n-hexane, a portion of supernatant was concentrated for analysis. A sensitive method was also optimized for the quantification of styrene dimer and trimer in foods such as instant cup noodle and yogurt by using GC/MS. Limits of Detection were about 3.2-87.0 ppb for styrene dimers and trimers. The highest recovery was obtained by extraction with acetone/hexane(1:1), followed by florisil clean-up. The levels of styrene dimer and trimer migrated by food simulants were much higher in heptane.

• Korean Journal of Microbiology
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• v.55 no.1
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• pp.58-60
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• 2019

Anaerobic Gram-negative bacterium Prevotella intermedia is a part of normal flora of the oral cavity and associated with various types of oral and systemic diseases. We present here a draft genome sequence of P. intermedia ATCC 15032, originally isolated from cervicofacial actinomycosis. The genome is 2,848,426 bp in length and has a GC content of 43.45%. The genome includes 2,358 protein-coding genes, 5 rRNAs, and 43 tRNA. The sequence information will provide important clues in understanding the genome diversity within the bacterial species, and genetic basis for phenotypic differences among P. intermedia strains.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.171-173
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• 2019

The genus Cohnella, which belongs to the family Paenibacillaceae, inhabits a wide range of environmental niches. Here, we report the complete genome sequence of Cohnella sp. HS21, which was isolated from the rhizospheric soil of Korean fir (Abies koreana) on the top of Halla Mountain in the Republic of Korea. Strain HS21 features a 7,059,027 bp circular chromosome with 44.8% GC-content. Its genome contains 5,939 protein-coding genes, 78 transfer RNA (tRNA) genes, 27 ribosomal RNA (rRNA) genes, 4 noncoding RNA genes (ncRNA), and 90 pseudogenes. The bacterium contains antibiotic-related gene clusters and genes encoding plant cell wall-degrading enzymes.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.157-159
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• 2019

Pseudomonas fluorescens NBC275 (Pf275) isolated from soil sample collected at riverside of Nakdonggang showed antagonistic activity against fungal pathogens of plants and insects. Here we present complete genome sequence of Pf275. The genome comprises of 6,610,362 bp with GC content of 60.9%, which includes 5,869 predicted protein-coding genes, 16 rRNAs, and 65 tRNAs. Genome analysis revealed gene clusters encoding antimicrobial secondary metabolites such as pyoverdine, 2, 4-diacetylphloroglucinol, and phenazine, which are known to play essential roles in biocontrol of diseases.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.286-288
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• 2019

Pseudomonas parafulva PpaJBCS1880 (PpaJBCS1880) isolated from rice seeds showed strong antagonistic activity against bacterial plant pathogens by producing lipopeptide. Furthermore, the strain controlled the incidence of bacterial pustule in soybean plants and promoted the growth of rice plants. Here we present complete genome sequence of PpaJBCS1880. The genome comprises of 5,208,480 bp with GC content of 63.4%, which includes 4,487 predicted protein-coding genes, 19 rRNAs, and 74 tRNAs. Genome analysis revealed genes encoding antimicrobial secondary metabolites such as lipopeptide, pyoverdine, phenazine, and hydrogen cyanide, which are known to play essential roles in biocontrol of plant diseases.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.450-455
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• 1996

In this study isolation and identification of squalene from amaranth and antineoplastic activity of its residue extract except squalene were determined to examine the utilization of grain amaranth in Korea. The content of squalene in amaranth grain was about 0.43%. The isolated squalene showed 99% pureness containing the identical molecular weight and structure provisionally in comparison with that of animal squalene from Sigma Co. by means of GC /Mass spectrum. Antineoplastic activity against human gastric and colon carcinoma cell line was measured in extract (except squalene) from Amaranth using MTT method. Extract from remaining plant good showed significant cytotoxic effect at the concentration of less than 230$\mu\textrm{g}$/ml.

• Journal of the Korean Society of Tobacco Science
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• v.12 no.2
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• pp.67-75
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• 1990

The pyrolytlc behavior of cocoa powder, a flavorant of tobacco smoking products, was examined by determining its pyrolyzate constituents. Cocoa powder was pyrolyzed of two cigarette smoking conditions'distillation-pyrolysis zone(35$0^{\circ}C$, 55$0^{\circ}C$) and high temperature zone($650^{\circ}C$, 85$0^{\circ}C$). Pyrolyzate was flushed from the tube by NB gas into CS2 trap in dry ice-acetone cooled bath and charcoal tube and its constituents were analyzed by GC/MS. As results, the major components of pyrolyzates were identified as hydrocarbon and phenolic compounds. In addition to these, aldehyde, ketone, pyrazin in very small amount. Component changes were observed with temperature increase; decane, styrene, tridecane, m-cresol,4-ethylphenol were increased while hexadecane, tetradecane were decreased. o-cresol and 2-ethylphenol were constant in amounts despite temperature change.

• Journal of Food Hygiene and Safety
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• v.33 no.4
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• pp.266-271
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• 2018

The Ministry of Food and Drug Safety (MFDS) is amending its test methods for health-functional foods (dietary food supplements) to establish regulatory standards and specifications in Korea. In this regard, we continue our research on developing analytical methods for the items. Octacosanol is the major component of polycosanol and is a high-molecular-mass primary fatty alcohol, obtained from sugar cane wax. Previous researchers have shown that octacosanol can lower cholesterol and has antiaggregatory properties, cytoprotective uses, and ergogenic properties for human health. Recently, octacosanol products have been actively introduced into the domestic market because of their functional biological activity. We have developed a sensitive and selective test method for octacosanol that the TMS derivatives by means of gas-chromatographic-tandem mass spectrometry (GC-MS). The trimethylsilyl ether derivative of the target analyte showed excellent chromatographic properties. The procedure was validated in the range of $12.5{\sim}200{\mu}g/L$. Standard calibration curves presented linearity with the correlation coefficient ($r^2$) > 0.999, and the limits of detection (LOD) and limits of quantitation (LOQ) were $4.5{\mu}g/L$ and $13.8{\mu}g/L$, respectively. The high recoveries (92.5 to 108.8%) and precision (1.8 to 2.4%) obtained are in accordance with the established validation criteria. Our research can provide scientific evidence to amend the octacosanol test method for the Health-Functional Food Code.

• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.260-270
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• 2022

In this study, we tested for pesticide residues in 114 samples representing 20 different types of fruit circulating in Gyeonggido. A total of 341 pesticides were identified via a multi-residue method using GC-NPD, GC-ECD, GC-MSMS, and LC-MSMS. In whole fruit, pesticides were detected in 48 cases, with a concentration range of 0.0025-0.1663 mg/kg. In the peels, pesticides were detected in 85 cases, with a concentration range of 0.0026-4.7185 mg/kg and a higher average concentration than was found in whole fruit. In the pulp, pesticides were detected in 8 cases, with a concentration range of 0.0021-0.0993 mg/kg. In most of the peels, pesticides were detected below MRL. In the kiwi peel, deltamethrin (with an MRL of 0.05 mg/kg) was detected at 0.1020 mg/kg. Since MRLs are applied to whole fruit, these levels are not unsuitable for ingestion. However, washing is recommended before ingestion to promote healthier and safer inclusion of the peel in the diet. Continuous monitoring of the peel and pulp is indicated.