• Korean Journal of Materials Research
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• v.28 no.1
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• pp.24-31
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• 2018

This study reports an environment-friendly synthetic strategy to process nickel oxide nanocrystals. A mesoporous nickel oxide nanostructure was synthesized using an environmentally benign biomimetic method. We used a natural rambutan peel waste resource as a raw material to ligate nickel ions to form nickel-ellagate complexes. The direct decomposition of the obtained complexes at $700^{\circ}C$, $900^{\circ}C$ and $1100^{\circ}C$ in a static air atmosphere resulted in mesoporous nickel oxide nanostructures. The formation of columnar mesoporous NiO with a concentric stacked doughnuts architecture was purely dependent on the suitable direct decomposition temperature at $1100^{\circ}C$ when the synthesis was carried out. The prepared NiO nanocrystals were coated on cotton fabric and their antibacterial activity was also analyzed. The NiO nanoparticle-treated cotton fabric exhibited good antibacterial and wash durability performance.

• Analytical Science and Technology
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• v.13 no.2
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• pp.131-135
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• 2000

We studied adsorption isotherm, surface properties and antibacterial activity of Cu treated activated carbon fiber (ACF). The BET surface area of Cu treated ACF are distributed to $688.2-887.8m^2/g$. The adsorption results show that BET surface areas move gradually to lower value with increasing treated Cu mole concentration. Using t-method, the specific micropore volumes and average pore size were obtained. From the SEM study, it is also observed that many of micropores in activated carbon fiber are blocked surface after the treatment. And we also observed that the activity of E. coli in kind of colon bacillus increases gradually to larger range with increasing Cu mole ratio. From these results, we suggest the antibacterial mechanism for metal treated ACF.

• Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.79-84
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• 2013

In an effort to discover an alternative antibiotic for treating infections with methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas sp. UJ-6, a marine bacterium that exhibited antibacterial activity against MRSA, was isolated. The culture broth and its ethyl acetate extract exhibited bactericidal activity against MRSA. The extract also exhibited antibacterial activity against gram-negative bacteria, which were not susceptible to vancomycin. The treatment of MRSA with the extract resulted in abnormal cell lysis. The extract retained >95% of its anti-MRSA activity after heat treatment for 15 min at $121^{\circ}C$. Thus, although most antibiotics are unstable under conditions of thermal stress, Pseudomonas sp. UJ-6 produces a heat-stable anti-MRSA substance. The results of this study strongly suggest that Pseudomonas sp. UJ-6 can be used to develop a novel, heat-stable, broad-spectrum antibiotic for the treatment of MRSA infections.

• Natural Product Sciences
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• v.24 no.1
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• pp.47-53
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• 2018

Callophylum symingtonianum (Guttiferae), an evergreen broad-leaved tree that usually grows in hill forests, can be found distributed in the Malay Peninsula. The barks, leaves, flowers and seeds is often used medicinally to treat diarrhea and rheumatism. In the present study, we isolated two inophyllum type coumarins, 12-O-ethylinophyllum D (1) and iso-soulattrolide (2) from the stembarks of C. symingtonianum together with their antibacterial activity. The compounds were isolated by chromatographic methods on a silica gel. The structures were established by spectroscopic methods including UV, IR, (1D and 2D) NMR and mass spectrometry as well as by comparison with several literature sources. The antibacterial activity of those compounds was tested using a disc-diffusion assay against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. Both compound exhibited mild inhibition against P. aeruginosa with both $111{\mu}g/ml$ MIC value. Compound 2 also inhibits S. aureus with $25{\mu}g/ml$ MIC value.

• Korean Journal of Veterinary Research
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• v.54 no.3
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• pp.189-192
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• 2014

This study evaluated the antibacterial effects of a mixture of Sophorae radix and Glycyrrhiza uralensis Fischer (1 : 1) ethanol extracts (SGE) on mice infected with Streptococcus (S.) pyogenes. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration of SGE necessary for antibacterial effects against S. pyogenes were $20{\mu}g/mL$. Based on the time-kill curves for S. pyogenes, SGE was effective at $4{\times}$ MIC after 16 h. On Day 12 after challenge, the survival rate of mice treated with 2.0 mg/kg SGE was 60%. In conclusion, SGE had potent in vitro and in vivo antibacterial activities against S. pyogenes.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.467-476
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• 2013

This study was conducted to investigate the effect of fermentation on biological activity of Chelidonium majus var asiaticum and to screen effective starter culture strains. Antibacterial activity against to Staphylococcus aureus, Listeria monocytogenes and Salmonella gallinarum and antioxidant activity as free radical scavenging activity by using DPPH were tested. Total six starter culture strains, two of Lactobacillus brevis, one of Lactobacillus plantarum and three of Saccharomyces cerevisiae were used. Plant extract was prepared after fermentation by using ethanol. All strains showed normal growth in viable cell counts of fermented cultures and L. plantarum showed the highest cell growth significantly (p<0.05). In antibacterial activities of extracts, the activity was found only in the extract from the fermentation using L. plantarum. In antioxidant activity, the highest activity was shown in the fermentation using L. plantarum significantly (P<0.05). Newly produced spots in two of three elution systems on TLC-DPPH test were detected in the fermentation using L. plantarum.

• Journal of the Korean Chemical Society
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• v.62 no.2
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• pp.93-98
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• 2018

Bis-GMA, TEGDMA, and camphorquinone were used as the main material, cross-linking agent, and photoinitiator, respectively. In addition, 2-isocyanatoethyl methacrylate was used as an additive for high strength, while the 3-hydroxypyridine was used as an additive for antibacterial activity. Photopolymerization was also carried out at a 440-480 nm wavelength and at about $1000mW/cm^2$ intensity for about 40 seconds. The breaking strength measurement of the samples showed that the breaking strength increased along with increasing the addition ratio of IEM, while it took less time until the polymerization was complete, thereby suggesting that the degree of polymerization has the tendency to increase. And also, compared to the size of the clear zone formed by ampicillin, the 3-hydroxypyridine group exhibited antimicrobial activity induced by ampicillin. The results of this study suggest that the use of 2-isocyanatoethyl methacrylate as an additive for high strength and 3-hydroxypyridine as an additive for improved antibacterial activity would improve the usability of the fabricated polymer as a dental resin cement material with high functionality.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.1
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• pp.104-112
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• 2008

Objective : This experimental study was preformed to investigate the effect of ethanol extract of Belamcandae Rhizoma (EBR) on dermal bioactive properties related to cosmeceuticals such as radical scavenging activity and depigmentation. Methods : The free radical scavenging activity of EBR was assayed in cell free systems using 1,1-diphenyl-2-picrylhydrazyl (DPPH). Antibacterial potency was measured by the size of inhibition zone with change of volume. Cell viability was measured by MTT assay and tyrosinase activity was assessed using L-DOPA. Results : EBR showed slightly radical scavenging activity and protected against UVB-induced cell cytotoxicity. Futhermore, EBR showed antibacterial activities on S. epidermidis and S. aureus. Although the proliferation of B16/F10 cells was decreased by EBR, necrosis was not revealed. EBR augmented tyrosinase activity and dendrite outgrowth in B16/F10 cells. Conclusions : These results suggest that EBR has antioxidative ＆ antibacterial activities, and stimulate melanogenesis.

• Environmental Engineering Research
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• v.11 no.6
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• pp.325-332
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• 2006

A novel series of polystyrene (PS) beads containing various sulfonamide groups was prepared, and their chemical stabilities in an aqueous solution were tested in order to determine their ability to inactivate microbes. By reacting aminomethyl polystyrene (AM PS) beads or carboxy polystyrene beads with various benzenesulfonic acid derivatives, the sulfonamide groups were introduced on the PS beads. The characteristics of the product beads were analyzed by elementary analysis after the substitution of various sulfonamide groups. Energy Dispersive Spectroscopy (EDS), and FT-IR analysis were used to analyze the elemental functional group composition, respectively. The hydrolytic stabilities of the PS beads containing various sulfonamide groups along with the relationship between the swelling ratio and their hydrophilicity were investigated. The antibacterial activity of the beads was determined by their ability to inactivate E. coli. This study reports that PS beads containing sulfonamide groups had lasting antibacterial efficacy over a satisfactory period, whilst maintaining their chemical stabilities against hydrolysis. The 8 synthesized polymer beads exhibited antibacterial ability.

• Korean Journal of Veterinary Research
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• v.45 no.1
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• pp.113-119
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• 2005

Resistance to antibiotics is a problem all over the world, and this problem also is so extended in veterinary fields. Therefore, this study aimed to find out the antibacterial substances from natural medicinal herbs against bovine mastitis pathogens, especially methicillin-resistant Staphylococcus aureus (MRSA). Among seventy two medicinal herbs, Terminaliae chebula extract showed antimicrobial effect against MRSA isolated from mastitis milk in cow and patient in human. However, Terminaliae chebula extract didn't show antibacterial effects on various strains including other contagious and environmental pathogens related with mastitis of dairy cows.