• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.156-161
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• 1996

세계적으로 구리약제에 대해서 저항성을 나타내는 균주들이 발견되있으며, 이들은 구리약제의 방제효과를 감소시켰다. 국내에서도, 구리 저항성 균주 Xanthomonas campestris. pv. vesicatoria HN94-2, -3, -4, -5, -6 들이 천안지역의 고추재배지에서 처음으로 분리되었으며, 이들 균주들의 nutrient agar에서 황산구리(CuSo\ulcorner)에 대한 최소억제농도(minimum inhibitory concentration, MIC)는 1.4~1.6 mM이었다. 이들은 모두 황산아연(ZnSO\ulcorner)에 대해서는 감수성을 보여, 구리저항성 균주에 대한 방제약제로서 아연 함유 약제를 사용할 수 있을 것이다. 분리된 균주중 HN94-2와 HN94-6을 이용하여 접합(conjugation)을 통해 구리저항성의 전파를 실험한 결과, 이들 두 균주 모두 구리감수성 균주에게 4.3$\times$10\ulcorner에서 1.0$\times$10\ulcorner(transconjugant/donor)의 정도로 구리 저항성이 전이되었다. 이들 HN94-2와 HN94-6 균주의 구리정항성 유전자들은 약 200 kb 정도의 커다란 플라스미드(plasmid)에 존재하며, 이들은 각각 pXVK9402와 pXVK9406이라 명명되었다.

• Food Science and Biotechnology
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• v.14 no.2
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• pp.286-289
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• 2005

Active antibacterial compound against periodontitis-causing bacterium Porphyromonas gingivalis was isolated from Kaempferia pandurata and identified as panduratin A. Minimum inhibitory concentration (MIC) value of panduratin A was $4\;{\mu}g/mL$, much lower than those of other natural antibacterial agents. Panduratin A also showed antibacterial activity against Prevotella intermedia ($2\;{\mu}g/mL$), P. loescheii ($4\;{\mu}g/mL$), and cariogenic Streptococcus mutans ($4\;{\mu}g/mL$). Damage on cell wall and perturbation of cytoplasmic membrane of panduratin A-treated P. gingivalis were visualized through transmission electron microscopy. These results suggest panduratin A, exhibiting strong and preferential antiperiodontal and anticariogenic activities, may be utilized in functional foods for prevention of oral diseases.

• Fashion & Textile Research Journal
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• v.4 no.6
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• pp.557-563
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• 2002

Water-soluble chitosan and water-insoluble chitosan with molecular weight of 2,000,000, 500,000, 80,000, and 40,000 with more than 90%of degree of deacetylation were produced to test antibacterial activity of chitosan against a pathogenic bacteria, Methicillin Resistant Staphylococcus aureus(MRSA). the AATCC Test Method 100and Modified AATCC Test Method 100 were used to evaluate the antibacterial activity of chitosan. Antibacterial activity of chitosan/acetic acid solution was the same when they were tested by two different methods, but those of polyester fabrics treated with chitosan/acetic acid solution were different in different antibacterial test. So several problems were found in the experimental methods. The AATCC Test Method 100 seems that excessive nutrition exists in inoculum solution by quantitative analysis on the basis the result of antibacterial activity on chitosan/acetic acid solution and amount of chitosan attached to the surface of treated fabrics.

• YAKHAK HOEJI
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• v.48 no.1
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• pp.20-26
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• 2004

Twelve strains of Bifidobacterium spp. were isolated from the feces of healthy Korean 20∼30 years. The identification of genera from isolates were performed by the microscopic observation and fructose-6-phosphate phosphoketolase (F6PPK) activity which is the key enzyme to distinguish the Bifidobacterium spp. from other anaerobic bacteria. To determine the antibacterial resistance patterns, minimum inhibitory concentration (MIC) of several antibiotics (including anti-tuberculosis agents) was determined. Five of the isolate!, showed the high degree of resistance to vancomycin. To investigate the genetic diversity between isolates and type strain of Bifidobacterium spp. from KCTC, we peformed the RAPD-fingerprinting. Using a total set of four primers, it is possible to distinguish the isolates and Bifidobacterium spp. from KCTC. Thus, Bifidobacterium strains isolated from our samples may be a new species or strains of Bifidobacteriurn genera, and have the potential as a probiotics.

• Textile Coloration and Finishing
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• v.12 no.3
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• pp.166-173
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• 2000

Various kinds of water soluble N,N,N-trimethylchitosan ammonium chloride(TMC) with different molecular weights were synthesized to examine the antimicrobial activity against Methicillin Sensitive Staphylococcus aureus(MSSA) and Methicillin Resistant Staphylococcus aureus(MRSA), which causes serious hospital infection, and to apply them to antimicrobial finishing agents for textiles. Chitosan samples were highly deacetylated with sodium hydroxide solution and degraded with hydrogen peroxide to control the molecular weight. TMC has the antimicrobial activities against MRSA and MSSA. TMC showed an excellent antimicrobial activity below the molecular weight of 70,000, especially at 40,000. The minimum inhibitory concentration (MIC) of TMC with optimum molecular weight against MRSA and MSSA was 250ppm. Because MRSA did not resist TMC in the subculture test of bouillon medium, it was expected that the successive use of TMC against MRSA was possible.

• Archives of Pharmacal Research
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• v.29 no.10
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• pp.815-820
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• 2006

Antibacterial activity-guided fractionation of the $CHCl_3-MeOH$ (1:1) extract of Paeonia suffruticosa root bark furnished three monoterpene glycosides, 6-O-vanillyoxypaeoniflorin (1), mudanpioside-H (2), and galloyl-oxypaeoniflorin (3). Of the isolated compounds, compound 1 is a new compound. All isolated compounds showed broad, but moderate, antibacterial activity with minimum inhibitory concentration (MIC) values in the range of 100 to $500\;{\mu}g/mL$ against eighteen pathogenic microorganisms of concern for public health or zoonosis.

• Food Science and Preservation
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• v.3 no.2
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• pp.187-193
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• 1996

To investigate the antimicrobial activities and effect of grapefruit seed extract(GFSE) on the physiological function of microorganism, antimicrobial activity, fatty acids of bacterial cell lipid and amino acids of bacterial cell protein were measured. The change of cell morphotype was observed by transmission electron microscope. GFSE was very stable on the wide range temperture and pH. The growth rate of E. coli and B. suvtilis were decreased above 40ppm GFSE There fore, minimum inhibitory concentration (MIC) of the E. coli and B. subtilis to GFSE were determined around 40ppm. In the change of fatty acids quantities, hexadecanoate was significantly decreased on the treatment compared with control in case of E. coli, whereas tridecanoate was not detected in case of B. subtilis. In the change of amino acids quantities, alanine, glutamic acid, glycine, lysine were decreased on the treatment compared with control in case of E. coli and B. subtilis Transmission electron microsgraphs(TEM) showed the microbial cells were destroyed by GFSE.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.13 no.1
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• pp.267-279
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• 2000

Minimum inhibitory concentration(MIC) of Sophorae Subprostratae Radix. Aconiti Radix, Hibisci Syriaci Cortex and those mixture. Phellodendri Cortex, Sophorae Radix, Torilis Fructuson on various species of the dermatophytes on Microsporium gypseum, Trichophytone rubrum and Epidermophytone floccosum were determined after 4 weeks of incubation at $25^{\circ}C$ in Sabouraud dextrose broth. The results were summarized as followes : 1. Antifungal effects of Phellodendri $Cortex\;{\cdot}Hibisci$ Syriaci Cortex and mixture of Sophorae Subprostratae Radix, Aconiti Radix, Hibisci Syriaci Cortex on T rubrum which is the most common organism of tinea pedis were more effective than that of the others. 2 These results suggested that herbal medicines such as Phellodendri $Cortex\;{\cdot}Hibisci$ Syriaci Cortex and mixture of Sophorae Subprostratae Radix, Aconiti Radix, Hibisci Syriaci Cortexse can be used to treat tinea pedis and to improve untoward effects associated with the administration of antifugual agents.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.27 no.2
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• pp.57-58
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• 2001

Biosurfactant has antibiological activities. Due to its low toxicity, biosurfactant can be applied to human health care products. Posseing the antibiological activities as well as the surfactant properties implies that biosurfactant can be widely used in the cosmetic industry. In this presentation, applications of biosurfactant have been reviewed including the antimicrobial activities of sophorolipid. Sophorolipid, a biosurfactant produced from Candida bombicola ATCC 22214, showed antimicrobial activity against Bacillus subtilis, Staphylococcus xylosus, Streptococcus mutans, and Propionibacterium acne at 4, 1, 1, 0.5 ppm as MIC (minimum inhibitory concentration). Also 100 ppm of sophorolipid inhibited 50% of cell growth of plant pathogenic fungus, B. cinera. However, sophorolipid showed no effect on the Escherichia coli., indicating its selective antimicrobial activity depending on the cell wall structure. Treatment of B. subtilis with sophorolipid increased the leakage of intracellular enzyme, malate dehydrogenase, indicating the possible interaction of sophorolipid with cellular membrane. Between lactone-type and acid-type sophorolipid, the former showed higher antimicrobial activity.

• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.459-465
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• 2011

BACKGROUND: Nowadays, Chemical antiseptics have become great problems for health and environmental, so that developing of new substitutes for chemical antiseptics is more and more important. Natural product is a kind of environment-friendly additive that could be used as antiseptic in food industry. Thuja orientalis cv Aurea Nana is a gymnospermous plant of the family Cupressaceae, native to northwestern China and widely naturalised elsewhere in Korea and Japan. This study was aimed to investigate the antibacterial potential of various organic extracts from T. orientalis cones against some food-borne and food-spoilage bacteria. METHODS AND RESULTS: Hexane extract (HE), chloroform extract (CE), ethyl acetate extract (EAE) and methanol extract (ME) were obtained from female cones of T. orientalis. The antibacterial activities of various extracts were tested by standard agar diffusion and minimum inhibitory concentrations (MICs) against five gram-positive and six gram-negative bacteria. Cell viability and morphology change of L. monocytogenes ATCC 10943 treated with hexane extract were also observed. The various extracts displayed remarkable antibacterial effects against all the gram-positive bacteria but did not show any effect against the gram-negative bacteria. Hexane extract has the highest inhibitory effect on cell viability of L. monocytogenes ATCC 10943. SEM observation also demonstrated the damaging effect of the hexane extract on the morphology of L. monocytogenes ATCC 10943 at the minimum inhibitory concentration. CONCLUSION(s): The tested gram-positive bacteria were significantly inhibited by organic extracts of T. orientalis cone. Hexane extract was the most potent against Listeria monocytogenes ATCC 10943, as evidenced by the lowest MIC level and the complete inhibition of cell viability within shortest exposure time, along with SEM observation.