• Animal Bioscience
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• 제35권1호
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• pp.138-146
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• 2022

Objective: The objective of the current study was to investigate the influences of conventional (CO) and deep litter (DE) systems on antimicrobial resistance in fecal Escherichia coli (E. coli). Methods: A cross-sectional study was carried out to detect antimicrobial resistance to E. coli in swine fecal samples in CO and DE systems located in western and northeastern Thailand. Individual rectal swab samples were taken only from healthy pigs. A total of 215 individual and healthy pigs were randomly selected for isolation and antimicrobial susceptibility test of E. coli by the disc diffusion method. The test panel included amoxicillin (AMX), colistin, doxycycline (DOX), enrofloxacin, gentamicin (GEN), kanamycin, neomycin (NEO), and trimethoprim-sulfamethoxazole (SXT). Results: There were significant (p<0.05) lower resistance levels for GEN, NEO, and SXT in the DE farms compared to those in the CO farms. There was a lower number of antimicrobial resistance agents (p<0.001) in the DE farms compared to those in the CO farms. This result was consistent with those in western (p<0.01) and northeastern (p<0.01) Thailand. Overall, antibiograms of AMX-SXT and AMX-DOX-SXT were found in the CO (19.09% and 20.91%, respectively) and the DE (16.19% and 24.76%, respectively) farms. No antimicrobial resistance (5.71%) was found and AMX (13.33%) resistant pigs in the DE farms, whereas the pattern of AMX-GEN-SXT (6.36%) and AMX-DOX-GEN-SXT (11.82%) resistant pigs was found in the CO farms. Conclusion: The DE system for pig farming was superior to conventional pig farming by lowering the resistance level of fecal E. coli to GEN, NEO, and SXT, with decreasing the number of antimicrobial resistance agents and inducing a small proportion of pigs to be free from antimicrobial resistance.

• 한국의류산업학회지
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• 제15권4호
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• pp.630-634
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• 2013

Cow leather coated with polyurethane film that contains various organic photosensitizers was investigated to demonstrate the antimicrobial properties in the application of the material to protective clothing and home appliances. To prepare the antimicrobial coating on leather surfaces with high potency against microbes, photoactive agents, such as benzophenone (BP), 4,4'-bis(dimethylamino) benzophenone (MK), 4,4'-dihydroxybenzophenone (DHBP) and methylene blue (MB), were incorporated into polyurethane-based coating solutions. The photoactive antimicrobial agent treated leather samples were characterized by SEM, color appearance, color fastness against abrasion, and antimicrobial tests. The optical properties of organic photosensitizers indicated that active UV absorbance ranges were different: BP (around 250 nm), MK (around 360 nm), DHBP (around 305 nm) and MB (around 295 nm &570 nm-685 nm). The intensity of the UV absorbance curve at the UVA light wavelength for the antimicrobial test showed the highest value with MK; subsequently, this was followed by MB, DHBP and BP in decreasing order. The treated-leather samples demonstrated excellent antibacterial activity under UVA light. The antimicrobial effects for the Staphylococcus aureus were superior to Escherichia coli. Moreover, the polyurethane finishing showed an effective durability to abrasion. The overall results indicated that DHBP is the most suitable PU coating additive to provide antimicrobial properties to leather as well as color and surface appearance than MK, MB, and BP.

• KSBB Journal
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• 제17권4호
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• pp.345-349
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• 2002

항균성 물질이 함유된 투명한 신기능 포장필름의 제조를 위하여 흡착제로서 수용성 silica를 선택하여 항균성 물질의 흡착 및 내열성을 조사하였다. Methanol 자화 방선균 (MO-16, MO-17)이 생산하는 천연 항균성 물질을 ethylacetate로 추출, 농축하여 silica에 흡착시킨 후 열처리한 결과 15$0^{\circ}C$에서 5분까지 항균효과가 유지되었다. 따라서 투명필름의 제조시에 흡착제로서 silica의 첨가가 효과적이라고 판단되었다. 항균제인 benzoic acid(BA) 는 세균 및 곰팡이에 강한 항균효과를 나타내었으며, 특히 곰팡이에 대한 항균력이 우수하였고, 10$0^{\circ}C$, 5분간 열처리시에도 항균력을 유지하였다. 또한 항균성 물질과 공동 첨가시 약간의 상승효과를 나타내어 필름 제조시 공동 첨가하므로서 첨가량의 감소에 따른 비용의 절감 및 항진균 효과가 보완된 필름제조가 가능하다고 사료되었다.

• Journal of Periodontal and Implant Science
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• 제32권1호
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• pp.249-255
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• 2002

Zea Mays L. has been known to be effective for improving tissue health and Magnoliae cortex to have effective antibacterial and antimicrobial activity against pathogenic microbes. The purpose of this study was to examine the antimicrobial effects of Zea Mays L. and Magnoliae cortex extract mixtures on periodontal pathogens(Prevotella intermedia, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Streptococcus mutans )and to examine the effects on human gingival fibroblast cellular activity. Zea Mays L. and Magnoliae cortex extracts and their mixtures were prepared with various mixing ratios (0.5:1, 1:1, 1.5:1, 2:1). These extracts were loaded to periodontal pathogen cultured petri dish for antimicrobial test and also loaded to cultured human gingival fibroblast for cellular activity test. Each test was repeated 3 times and data were analyzed by one-way ANOVA with 95% confidence level. Mixture of these two extracts showed greater amount of inhibition area on periodontal pathogen and more improved gingival fibroblast activity as Zea Mays L. ratio reduced. So, mixture ratio 0.5:1 (Zea Mays L. : Magnoliae cortex) group showed statistical significance in antimicrobial activity and cellular activity among various mixtures(p < 0.05). In conclusion, 0.5:1 (Zea Mays L. : Magnoliae cortex) mixture possessed best gingival fibroblast cellular activity and antimicrobial activity toward periodontal pathogens.

• 한국식품과학회지
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• 제34권4호
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• pp.700-709
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• 2002

식품에 사용가능한 천연식품보존제를 개발하기 위하여 총 62종이 특용작물을 대상으로 실험하였다. 공시된 62종의 특용작물에 대한 물추출물 및 80% 에탄올 추출물을 제조하였으며 Escherchia coli, Listeria monocytogens 및 Candidia albicans의 3종의 미생물을 대상균주로 하여 paper disk method에 의해 항균력을 측정하였으며 그 결과 7종의 특용작물을 1차로 선발하였고 이후 정밀실험을 통하여 복분자 (Rubus coreanus miquel), 가자육(Therminalia chebula Retz), 오배자(Rhus javanica) 3종의 특용작물을 최종 선발하였다. 선발된 3종의 특용작물에 대한 항균 spectrum 측정 결과 가자육과 오배자 추출물이 비교적 넓은 항균 spectrum을 가지고 있었다. 최소성장억제농도인 MIC(minimal inhibition concentration)를 측정한 결과 가자육과 오배자 추출물이 낮은 수치의 MIC를 가지고 있는 것으로 나타났다. 액체배양시 균주의 성장억제에 미치는 영향을 측정한 결과 Listeria monocytogens에 대한 생육억제 활성이 매우 우수한 것으로 나타나 천연 식품보존제로서의 가능성이 있음을 알 수 있었다.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.700-706
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• 1994

Lactic acid bacteria in Kimchi fermentation were tested for inhibitory activity against Gram positive bacteria and Gram negative bacteria. The Lactobacillus brevis (KCCM 35464) was found to produce a antimicrobial substance. It showed relatively wide range of inhibition spectrum against gram positive and gram negative bacteria and maintained the inhibitory activity between pH 4.0 and pH 9.0. The antimicrobial substance was obtained in the stationary growth phase and was purified by gel chromatography. The inhibitory effect of the antimicrobial substance on sensitive bacterial strains was determined by filter paper test. The activity of antimicrobial substa- nce was stable at 75$\circ$C. On the basis of its electrophoretic pattern is SDS-PAGE, antimicrobial substance appeared as a single band of 59 KDalton.

• 한국염색가공학회지
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• 제12권3호
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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.

• 한국식품영양과학회지
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• 제27권2호
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• pp.232-238
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• 1998

To developed natural food preservatives, ethanol and water extracts were prepared from the defatted camellia(Camellia japonica L.) seeds. Antimicrobial activities were examined against 14 microorganisms which were food borne pathogens and/or food poisoning microorganisms and food-related bacteria and yeasts. Ethanol extract showed antimicrobial activities against several microorganisms tested, but not on lactic acid bactria. Especially, minimum inhibitory concentrations(MIC) for yeasts were as low as 1mg/ml. Water extract exhibited antimicrobial activities for the yeasts tested, but almost bacteria were not observed. The ethanol extract was fractionated in the order of hexane, chloroform, ethylaetate and butanol fractions to test antimicrobial activity. The strongest activity for the tested yeasts were found in the butanol fractions, but bacteria were chloroform fraction. Hansenula anomala treated with ethanol were observed by scanning electron micrograph, and the results exhibited morphological changes, including the irregularly contracted cell surface and expanded ellipsoidal shape.

• 한국동물위생학회지
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• 제30권3호
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• pp.339-351
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• 2007

Salmonella infections cause the diseases in poultry and some zoonotic Salmonella can be transmitted to human through poultry products, resulting in food-borne disease. This study was conducted to obtain some useful information for the control of salmonellosis in human. Twenty four Salmonella spp were isolated from poultry carcasses, and they were examined with several methods such as serotyping, antimicrobial resistance test and random amplified polymorphic DNA(RAPD) to identify their characteristics. In serotyping test of 24 strains S enteritidis was 17 (70.8%), followed by S schwarzengrund 3 (12.5%), untyped strain 4 (16.7%). In the results of antimicrobial resistance test, 23 (95.8%) isolates were resistant to at least one antimicrobial agent, generating eight different resistance patterns. In RAPD analysis using URP-6 primer to differentiate Salmonella isolates within a serotype, 4 serogroups were divided into 10 RAPD types: 5 types in S enteritidis, 2 types in S schwarzengrund and 3 types in the remainder.

• 생명과학회지
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• 제10권5호
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• pp.524-528
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• 2000

택사(Alismatis Rhizoma)는 중국에서 많이 생산되고, 우리나라에서도 그 생산량의 50%이상이 전남 순천지방에서 생산되고 있는데, 옛부터 생약으로 많이 사용되어 왔으며, 최근 택사분말은 무좀에 도포약으로 쓰이고 있어 택사에는 다양한 생리활성이 있는 것으로 생각된다. 따라서 본 연구에서는 추출용매에 따른 택사 추출물에 대한 항균 및 항산화성에 대하여 조사하였다. Paper disc법에 의한 택사 추출물의 항균 test결과 물추출물에서는 거의 모든 시험균주에서 항균활성이 나타났으나, 메탄올 및 에탄올 추출에서는 그 활성이 작게 나타났으며, 시험균주중 Vibrio parahaemolyticus균에 가장 강한 항균활성을 나타내었다. Linoleic acid에 대한 항산화력의 조사에서 택사 물추출물 100$\mu{l}$첨가시 메탄올 및 에탄올 추출물은 항균효과 나타나지 않았고, 물추출물은 효과가 나타났으나 0.1% BHT첨가시 보다는 그 효과가 적었다.