• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.37-37
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• 2017

Mechanistic studies of halophytes are urgent areas of agricultural research due to the increase in saline-contaminated and irrigated land worldwide. The halophyte Suaeda glauca (S. glauca) has advantages in terms of biomass and saline elimination due to its large mass and well-developed phenotype on seashores, although its mechanistic features and growing specificities still require systematic investigation. In this study, S. glauca was cultivated under various saline concentrations (0-400 mM) in Hoagland's solution in the absence or presence of indole derivatives to elucidate physiological features. The results confirmed the optimal growth and development of S. glauca in 50 mM NaCl, and morphologies such as the number of branches, shoot length, and fresh and dry weights were improved by indole-3-carboxylic acid (ICA) treatment. The cation concentrations in roots, shoots and leaves were investigated to examine the ionic imbalances in response to saline treatment, and the results demonstrated that sodium ions accumulated to high concentrations in leaves. The levels of calcium and potassium ions in roots were maintained or slightly decreased in the presence of 50 mM NaCl and proline concentration was increased significantly in roots at optimal concentrations. These results demonstrate that the concentrations of ions and metabolites are key regulators of optimal growth by regulating the physiology of halophytes.

• Korean Journal of Veterinary Research
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• v.55 no.2
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• pp.81-88
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• 2015

This study was conducted to isolate lactic acid bacteria (LAB) from dog intestine and identify potential probiotic strains for canine use. One hundred and one LAB were isolated from feces of 20 healthy dogs. Acid, bile, and heat resistance along with adherence to Caco-2 cells and antimicrobial activity against pathogens were examined. To analyze immunomodulative effects, the production of nitric oxide (NO), TNF-${\alpha}$, and IL-$1{\beta}$ was measured using RAW 264.7 macrophages. Additionally, RAW BLUE cells were used to evaluate nuclear factor-${\kappa}B$ (NF-${\kappa}B$) generation. Ultimately, three strains were selected as canine probiotics and identified as Lactobacillus reuteri L10, Enterococcus faecium S33, and Bifidobacterium longum B3 by 16S rRNA sequence analysis. The L10 and S33 strains showed tolerance to pH 2.5 for 2 h, 1.0% Oxgall for 2 h, and $60^{\circ}C$ for 5 min. These strains also had strong antimicrobial activity against Escherichia coli KCTC 1682, Salmonella Enteritidis KCCM 12021, Staphylococcus aureus KCTC 1621, and Listeria monocytogenes KCTC 3569. All three strains exerted better immunomodulatory effects than Lactobacillus rhamnosus GG (LGG), a well-known commercial immunomodulatory strain, based on NO, NF-${\kappa}B$, IL-$1{\beta}$, and TNF-${\alpha}$ production. These results suggested that the three selected strains could serve as canine probiotics.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2311-2314
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• 2016

Pistagremic acid (PA) is a bioactive triterpenoid isolated from various parts of Pistacia integerrima plants. The aim of this research was to investigate PA for reversion of multidrug resistant (MDR) mediated by P-glycoprotein using rhodamine-123 exclusion study on a multidrug resistant human ABCB1 (ATP-binding cassette, sub-family B, member 1) gene-transfected mouse T-lymphoma cell line in vitro. Results were similar to those with verapamil as a positive control. Docking studies of PA and standard Rhodamine123 were carried out against a P-gp crystal structure which showed satisfactory results. Actually, PA cannot bind exactly where co-crystallized ligand of P-gp is already present. However, the docking study predicted that if a compound gives a lesser score then it may have some potency. The docking scores of PA and Rhodamine were similar. Therefore, we can conclude that there are certain important chemical features of PA which are responsible for the inhibiting potency of P-gp.

• Journal of Microbiology and Biotechnology
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• v.11 no.5
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• pp.831-837
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• 2001

Pediocin K1, a bacteriocin produced by Pediococcus sp. K1 isolated from Korean traditional fermented flatfish, inhibited certain strains of Lactobacillus, Streptococcus, and Listeria monocytogenes. Pediocin K1 was found to be stable at $90^{\circ}C$ for 30 min. Among the organisms tested, Listeria monocytogenes was the most sensitive to pediocin K1 and was completely killed when the initial inoculum size of L.monocytogenes cells was equal to or less than $10^3 CFU/ml$. The degree of inibition of Listeria monocytogenes by pediocin K1 increased 10-fold on the addition of citric acid ($0.2\%$) to the medium, thereby showing the synergistic effect of citric acid. Listeria monocytogenes cells resistant to pediocin K1 appeared at a frequency of about $10^-4$/cells. Once developed after exposure to pediocin K1, the resistant phenotype still persisted in the absence of pediocin K1 in successive cultures. This infers that resistance may be attributable to genetic change(s) in the resistant cells.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.177-184
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• 2009

Three hundred lactic acid bacteria isolated from human feces were studied their probiotic characters to develop potential probiotics. The properties were tested on the basis of guideline for probiotic selection protocol such as tolerance for acid or bile salt, thermal stability, antimicrobial, anticancer cell, and antiviral activity. Strain Miny-148 was selected as a potential probiotic bacterium which showed resistance to low pH, bile salts and thermal stability. On the basis of fatty acid profiles and 16S rDNA sequences analysis, the strain was identified as Lactobacillus pentosus (similarity 99.9%). The strain, L. pentosus Miny-148, showed broad antimicrobial spectrum against E. coli O157:H7, Shigella flexneri, Bacillus anthracis, Staphylococcus aureus, E. coli, Vibrio cholerae, V. vulnificus, Salmonella typhimurium, and Methicillin-resistant S. aureus (MRSA). Cell-free culture supernatant of the strain also inhibited against the growth of HT-29 colon cancer cell and transmissible gastroenterits virus.

• Korean Journal of Microbiology
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• v.50 no.3
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• pp.233-238
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• 2014

For the collection of starters suitable for the brewing of traditional liquor, an alcohol-resistant strain of lactic acid bacteria with low level of acid production was isolated from traditional fermented soybean lumps. The strain named as JBE 30 was identified as Lactobacillus brevis by 16S rRNA sequence analysis and additional biochemical tests. The strain could grow well at a MRS medium containing 8% (v/v) ethanol for 96 h of cultivation at $30^{\circ}C$. The final pH after cultivation was 4.5. It also inhibited the growth of food spoilage and pathogenic bacteria including Escherichia coli, Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Micrococcus luteus, and Pseudomonas aeruginosa. These results showed that Lactobacillus brevis JBE 30 could be used as a promising starter in brewing process of traditional liquor.

• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.642-648
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• 2020

In this study, we investigated the effects of linoleic acid (LA) treatment on Brucella abortus infection in professional phagocyte RAW264.7 cells, particularly during the pathogen's invasion and intracellular growth in these cells, as well as in murine model BALB/c mice focusing on bacterial splenic proliferation and immunoregulatory activities. LA inhibited the growth of Brucella in a dose- and time-dependent manner. The ability of the pathogen to enter the phagocytes was inhibited as was its survival within these cells. This was accompanied by increased nitrite accumulation in these cells at 24 h post-infection. The concentration of LA used in the present study did not affect the total body weight or liver function of the mice. During Brucella infection, the total splenic weight of these animals was not changed; rather, resistance to bacterial proliferation was enhanced in the spleen. Furthermore, mice treated with LA displayed elevated levels of IL-12 and IFN-γ but reduced levels of IL-10 during infection. The findings in this study showed the regulatory role of LA against B. abortus infection suggesting its potential use in designing intervention strategy for brucellosis.

• The Plant Pathology Journal
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• v.19 no.2
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• pp.85-91
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• 2003

Pre-treatment with DL-3-aminobutyric acid (BABA) in the cucumber plants caused the decrease of disease severity after inoculation with anthracnose pathogen Colletotrichum orbiculare. In this study, ultrastructures of the vascular bundle and the infection structures in the leaves of BABA-treated as well as untreated cucumber plants were observed after inoculation with the anthracnose pathogen by electron microscopy. The ultrastructures of vascular bundle in the leaves of BABA-treated plants were similar to those of the untreated plants except plasmodesmata. In the BABA-treated plants, the plasmodesmata were more numerous than in the untreated plants, suggesting that the BABA treatment may cause the active transfer of metabolites through the vascular bundle. In the leaves of untreated plants, the fungal hyphae were spread widely in the plant tissues at 5 days after pathogen inoculation. Most cellular organelles in the hyphae were intact, indicating a compatible interaction between the plant and the parasite. In contrast, in the leaves of BABA pre-treated plants the growth of most hyphae was restricted to the epidermal cell layer at 5 days after inoculation. Most hyphae cytoplasm and nucleoplasm was electron dense or the intracellular organelles were degenerated. The cell walls of some plant cells became thick at the site adjacent to the intercellular hyphae, indicating a mechanical defense reaction of the plant cells against the fungal attack. Furthermore, hypersensitive reaction (HR) of the epidermal cells was often observed, in which the intracellular hyphae were degenerated. Based on these results it is suggested that BABA causes the enhancement of defense mechanisms in the cucumber plants such as cell wall apposition or HR against the invasion of C. orbiculare.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.463-468
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• 1998

When sulfuric acid was added in HCl etching solution, corrosion of aluminum metal was inhibited by the chemical adsorption of sulfate ions. In the presence of $SO_4^{-2}$, cyclic voltammetry showed that the protective oxide film was formed on the inner surfaces of etch pits and, pit density was increased by nucleation on both the aluminum surface and the pits inside. Structure and distribution of etch pits found in AC etching of aluminum were strongly influenced by the concentration of $SO_4^{-2}$ and the amount of cathodic pulse charging. Below $0.8mC/cm^2$ of cathodic pulse charging, oxide films formed inside actively dissolving pits indicated the higher resistance to pit nucleation as the concentration of $SO_4^{-2}$ increases. However, the structural change of oxide films occurred above the $0.8mC/cm^2$ charging and the effect of $SO_4^{-2}$ was minimized, and it resulted in the rapid formation of etch pits.

• Polymer(Korea)
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• v.28 no.6
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• pp.494-501
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• 2004

A new alkali developable photosensitive poly(amic acid) (PAA-0) with transmittance at 400 nm was synthesized from cyclobutane-1,2,3,4-tetracarboxylic dianhydride, 2-(methacryloyloxy)ethyl-3,5-diamino-benzoate and 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyl disiloxane in N-methyl-2-pyrrolidinone. Photosensitivity of the PAA-0 was investigated at 365-400 nm in the presence of a photoinitiator using a high pressure mercury lamp. The photo-cured poly(amic acid) was insoluble toward aqueous 2.38 wt% tetramethylammonium hydroxide solution. Negative pattern of the PAA-0 with 25 ${\mu}{\textrm}{m}$ resolution was obtained by developing with 2.38 wt% tetramethylammonium hydroxide solution after exposure of 600 mJ/$\textrm{cm}^2$ in the presence of 2,2-dimethoxy-2-phenyl-acetophenone as a photoinitiator. The patterned poly(amic acid) was converted to polyimide by thermal curing at 25$0^{\circ}C$ for 50 min, which showed chemical resistance against photoresist stripper as well as good transmittance at 400 nm.