• Journal of Food Hygiene and Safety
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• v.8 no.1
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• pp.9-15
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• 1993

In an attempt to quantitate and qualitate residual antibiotics and antibacterial agents in meat simultaneously, we studied a gas chromatography-mass spectrometry(GC/M8) analysis. For a simultaneous analysis of penicillin G, chloramphenicol and thiamphenicol in meat, a simple and rapid clean-up procedure including extraction with 0.01 M EDTA-2Na Mcilvaine buffer (pH 4.0), defatting with n-hexane, and elution with 0.01M-methanolic oxalic acid from Bond Elute $C_{18}$ cartridge, and quantitation by selected ion monitoring (SIM) mode after derivatization was performed. The recoveries (%) of penicillin G, chloramphenicol and thiamphenicol (CV, %) at 1 ppm fortification level were 63.5 (7.6), 76.3 (8.1) and 84.7 (2.0), and the detection limits of those were 0.6, 0.085 and $0.084\;\mu\textrm{g}$ beef, respectively. This method using 81M mode allows excellent detection and quantitation of residual antibiotics and antibacterial agents in meat. Moreover, confirmation by a full scan electron impact mass spectrum is possible if residual level in the sample in above 1 ppm.

• Journal of Life Science
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• v.31 no.3
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• pp.330-337
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• 2021

This study was conducted to investigate the potential of Stewartia koreana as oral healthcare materials. The antibacterial activity of ethanol extracts from leaves and branches of S. koreana against oral bacteria was confirmed. The leaf and branch extracts (1 mg/disc) showed antibacterial activity against P. gingivalis only among several tested oral bacteria. The leaf extracts showed higher antibacterial activity, with values similar to those of chlorhexidine, which was used as a positive control. The MIC of the leaf extract against P. gingivalis was 0.4 mg/ml and showed bacteriostatic action. The inhibitory effects of the extract on biofilm formation and on gene expression related to biofilm formation by P. gingivalis were determined by biofilm biomass staining, scanning electron microscopy (SEM), and qRT-PCR analysis. The biofilm production rate and cell growth of P. gingivalis in the cultures treated with 0.2-2.0 mg/ml of S. koreana leaf extracts were significantly decreased in a concentration-dependent manner. The inhibitory effect on the formation of P. gingivalis biofilms at concentrations of 1 mg/ml was confirmed by SEM. The qRT-PCR analysis showed concentration-dependent suppression of the fimA and fimB gene expression associated with fimbriae formation in the cultures treated with 0.2-2.0 mg/ml S. koreana leaf extract. These results support the conclusion that S. koreana leaf extracts can be used as oral healthcare materials derived from natural materials, as demonstrated by the antibacterial action and inhibition of biofilm formation of P. gingivalis.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.825-839
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• 2014

Antioxidant activity is important for reducing oxidative stress that causes various metabolic disorders. Metabolic disorders are highly related to loss of productivity in livestock. Therefore, development of effective antioxidant compounds originating from plants is important for organic agriculture. Phenolic compounds in edible plants are regarded as major components relevant to antioxidant activity. The present study investigated the changes in antioxidant activity and phenolic compound profiles of Aronia (Aronia meloncarpa) by fermentation using different strains of Leuconostoc mesenteroides. A total of 5 strains of L. mesenteroides were used as starter cultures and their ${\beta}$-glucosidase activities were measured. A total of 6 experiment runs were prepared, one for control (uninoculated) and the others (inoculated) for treatments. For biological activity, antioxidant and antibacterial activities were measured. For phenolic compound profiling, TLC and HPLC analysis were performed. The strains of KACC12313 and KACC12315 showed greater enzyme activity than others. Treatment with KCCM35046 showed strong and broad antibacterial activity against to Listeria monocytogenes. Treatments with KCCM35046 and KACC12315 showed the highest total polyphenol content. The highest antioxidant activity was found in KACC12315 treatment. No remarkable alteration was found in thin layer chromatography (TLC) analysis. In phenolic compound profiling analysis, KCCM35046 showed notable alteration in compound area ratio compared to others and also showed the highest caffeic acid content. In chlorogenic acid, treatments with KCCM35046 and KACC12315 showed great content than others. Treatment with KACC12315 showed the greatest content of trans-ferulic acid. As a result of relative performance indexing analysis, L. mesenteroides KCCM35046 and KACC12315 were selected as the best strain for the fermentation of Aronia.

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1791-1794
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• 2013

Phytochemical investigation on dragon's blood of Dracaena cambodiana led to the discovery of two new flavonoid derivatives, cambodianin G (1) and cambodianin H (2). Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1D and 2D NMR techniques and chemical methods. The two compounds were observed to exhibit antibacterial activities against Staphylococcus aureus, and compound 1 showed cytotoxicities against K562 and SGC-7901 cell lines.

• Fashion & Textile Research Journal
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• v.17 no.5
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• pp.828-837
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• 2015

The results of the analysis of dyed rayon fabrics treated with persimmon juice by padding are as follows. Rayon fabrics were dyed repeatedly with persimmon juice by a padding mangle for the development of dyeability. The merits of padding-based dyeing were easier color reproduction (versus traditional hand dyeing) of hard to obtain colors and color fastness to light and laundering. The add on weight increased with the number of padding times, and the color of the dyed fabrics had red-yellow colors with low brightness and high chromatic colors. Properties of fabrics treated with persimmon juice were: $2^{nd}$ level of light resistance, $4^{th}-5^{th}$ perspiration fastness levels, rubbing fastness, and $3^{rd}-4^{th}$ washing fastness levels. Dyed fabrics exposed to UV light have a deep yellow-red color that increased lightness and darken when exposed to sunlight. Rayon fabrics of a treated premordant indicated strong yellow colors, especially fabrics with Fe mordant indicated greenish red-yellow colors. The direction of the weft and warp increased and improved water-repellent qualities that increased with the number of dyeing padding times and persimmon juice; however, there was less anti-crease resistance. In addition, fabrics had good antibacterial activity and deodorization.

• International Journal of Industrial Entomology and Biomaterials
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• v.17 no.2
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• pp.217-221
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• 2008

Dung beetle larvae at the $3^{rd}$ instar were injected with lipopolysaccaride and inducible proteins were examined within a pI level of 3-10 and a size level by proteomics, including 1-D SDS PAGE analysis and antibacterial assay. The immune infected larvae extracts provided seven protein bands in one-dimensional electrophoresis and its antibacterial activity also checked. Hemolymph protein from immune infected larvae of the dung beetle were separated by twodimensional gel electrophoresis and compared with those from native larvae. In 2-D gel electrophoresis, we detected 63 immune infected unique and 32 up-regulated proteins, and 36 proteins that were down-regulated or not present in treated gel. Ten protein spots from unique proteins and those presented as different level of abundance in infected and native larvae were specially expressed. These differentially expressed proteins were proposed to be involved in the defense mechanism against microorganism.

• KSBB Journal
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• v.32 no.2
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• pp.153-159
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• 2017

The purpose of this study was to investigate the probiotic properties of lactic acid bacterial strains isolated from human feces. The properties were tested on the basis of guideline for probiotic selection protocol such as tolerance for acid or bile salt, autoaggregation, antibiotic resistance, and antimicrobial activity. Total 25 lactic acid bacteria were isolated from human feces, and their antibacterial activity was tested against Staphylococcus aureus, Escherichia coli, E. coli O157:H7, Vibrio parahaemolyticus, V. alginolyticus using an agar diffusion assay. Among them, 4 selected strains were identified by analysis of their 16S rRNA, as Lactobacillus rhamnosus MG316, L. acidophilus MG501, L. reuteri MG505, and L. gasseri MG570. Results show that resistance to low pH and bile salts. Also, the selected strains were resistant to bile acid up to 3% and their autoaggregation rates were as high as 60%. All strains tested were resistance to nalidixic acid and kanamycin.

• KSBB Journal
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• v.27 no.3
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• pp.161-166
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• 2012

The purpose of this work was to examine the antibacterial activity derived from a lactic acid bacterium isolated from korean rice wine, called makgeolli. Various physiological and biochemical properties of this strain were characterized. Both the BIOLOG system and phylogenetic analysis using 16S rRNA sequencing were utilized for identification, and the strain was designated as Lactobacillus casei HK-9, and registered in GenBank as [JQ951606]. Growth rate, production of organic acids (e.g., lactic acid and acetic acid), and pH changes during growth were monitored. The maximum concentrations of lactic acid and acetic acid were approximately 576 mM and 199 mM, respectively, and pH was changed from 7.00 to 3.74 after 72 h of incubation. HPLC was used to confirm the production of lactic acid and acetic acid. Significant antimicrobial activity of the concentrated supernatant was demonstrated against various food-poison causing bacteria (e.g., Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Escherichia coli, Salmonella enteritidis). Ethanol tolerance of L. casei HK-9 showed up to 12% of ethanol within the culture.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.23-31
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• 2009

To compare the effects of nanometer-sized silver ions and support materials (nano-silver coating material, NM-silver) and silver ions, we exposed zebrafish embryos to both types of nano-silver ions and compared the acute responses during embryogenesis. The amount of silver in the NM-silver (17.16%) was greater than that in the silver ion (4.56%). Both of these materials have different atomic compositions. The silver ion-exposed groups (10 and 20 ppt) showed lower survival rates than the NM-silver-exposed groups (10 and 20 ppt). NM-silver penetrated the skin and blood tube of zebrafish larvae as aggregated particles, whereas, silver ions penetrated the organelles, nucleus and yolk in a spread-out pattern. Micro-array analysis of RNA from zebrafish larvae (72 hours post-fertilization) that were treated with either NM-silver or silver ions, showed alteration in expression of the BMP, activin, TGF-$\beta$, and $GSK3{\beta}$ genes pathway. Additionally, $GSK3{\beta}$ gene pathway for apoptosis that was related with left-right asymmetry. Gene expression changes in the NM-silver or silver ions-treated zebrafish embryo led to phenotypic changes in the hatched larvae, reflecting increased apoptosis and incomplete formation of an axis.

• Membrane and Water Treatment
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• v.8 no.6
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• pp.563-574
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• 2017

Antibacterial effective, high performanced, novel ZnO embedded composite membranes were obtained by blendig ZnO nanoparticles with polysulfone. IR, TG/DTG, XRD and SEM analysis were performed to characterize structure and morphology of ZnO nanoparticles and composite membranes. Contact angle, EWC, porosity and pore structure properties of composite membranes were investigated. Cross-flow filtration studies were performed to investigation of performances of prepared membranes. It was found from the cross section SEM images that ZnO nanoparticles dispersed homogenously up to additive amount of 2% and the membrane skin layer thicknesses increased in the presence of ZnO. Contact angle of pure PSf membranes were reduced from $70^{\circ}$ to $55^{\circ}$ after addition of 4% ZnO. Porosity of composite membrane contains 1% ZnO was higher about 22% than pure PSf membrane. BSA rejection ratio and PWF of 0.5% ZnO embedded composite membrane became 2.2 and 2.3 times higher than pure PSf membrane. It was determined from flux recovery ratios that ZnO additive increased the fouling resistance of composite membranes. Also, the bacterial killing ability of ZnO is well known and there are many researches related to this in the literature. Therefore, it is expected that prepared composite membranes will show antibacterial effect.