• Korean Aquaculture
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• v.19 no.1
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• pp.52-57
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• 2007

Chum salmon의 알이 부화하는 동안 물곰팡이의 감염으로부터 보호하기 위해 알을 10 mg/L 염소농도의 하이포아염소산나트륨(NaOCl) 용액에 매일 15분간 수정란에서부터 발안기까지 처리하였다. 감염된 알의 수 및 발안기 알의 수는 부화 23일째 관찰하였다. 전체의 알에서 감염된 알의 비율은 대조구(11.3;59.3%)보다 NaOCl 처리한 실험구(1.8; 33.4%)에서 유의적으로 낮게 나타났다(P<0.01). 전체 알에 대한 발안란의 비율은 대조구(66.1:97.5%)보다 NaOCl처리한 실험구(85.9:98.6%)에서 유의적으로 우수한 경향을 보였다(P<0.01). NaOCl의 항균 활성은 알의 생존율을 향상시킨다. 따라서 NaOCl는 chum salmon의 난에 대한 물곰팡이의 감염에 대하여 아주 유용한 항균물질이라고 판단된다.

• Journal of Life Science
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• v.13 no.6
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• pp.943-949
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• 2003

New quinolone derivatives of 7-(cis- or trans-3-amino-4-mehtylthiomethylpyrrolidinyl) quinolone-3-carboxylic acids were synthesized by condensation of 7-halo substituted quinolone-3-carboxylic acids with cis- or trans-3-amino-4-mehtylthiomethylpyrrolidine. Some of these compounds showed broad spectra of antibacterial activities against Gram-positive and Gram-negative organisms except Pseudomonas aeruginosa, and exhibited much stronger activity against MRSA.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.52-53
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• 2013

According to the increases the standard of living of the people, requirements for building environments are also being diversified. The fungus that occurred the building is not good the health of occupants as well as undermine the value of the building. However, chemical antimicrobial agent contain ingredients harmful to human body and it has an impact on indoor air quality. Therefore, the use of natural antimicrobial material is strongly required. In this study, the fungal reproductive inhibit capacity was evaluated by using mortars with natural antimicrobial material.

• Korean Journal of Veterinary Service
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• v.25 no.3
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• pp.229-236
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• 2002

This study was carried out to compare the residual antibiotic materials in muscles of slaughter cattle and swine from slaughterhouses in Seoul from 2000 to 2001 by EEC-4-plate method, Charm II and HPLC method. 1. Residual antibiotic materials were detected from 95 samples(0.8%) by EEC-4-plate and 57 samples(10.2%) by Charm II. The final HPLC method determined the positives are 43(45.3%) and 27(47.3%) respectively. 2. The detection ratios were 45% by EEC-4-plate and 47% by Charm II. 3. Seventy samples were classified as tetracyclines 56(75.7.4%), sulfonamides 10(14.9%), $\beta$-lactam 6(8.1%) chloramphenicol 1(1.4%). Three of them were confirmed to be positive simmultaneously for tetracyclines, sulfonamides and chloramphenicol. 4. The highest residual concentration of chlortetracycline, oxytetracycline, sulfamethazine, sulfadimethoxine, sulfaquinoxaline, penicillin, ampicillin and chloramphenicol were 0.34, 11.29, 68.16, 0.13, 4.0, 0.12, 0.4 and 0.04ppm, respectively.

• Journal of Life Science
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• v.20 no.8
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• pp.1254-1260
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• 2010

Microorganisms near the plant rhizosphere usually inhabit the surface or the inside of the plant roots and have a direct effect on plant growth by secreting plant growth promoters or antagonistic materials which protect the root zone system from various pathogens. This study was carried out to identify and isolate the antagonistic materials after isolation of microorganisms showing high antagonistic activities, in hopes of contributing to the development of sustainable agriculture and the preservation of agricultural environments. A number of antagonistic bacteria were isolated from paddy soil. Among isolates, RRj 228 showed plant growth promotion and antagonistic activity. RRj 228 was identified as Pseudomonas sp. according to the results of physiological properties and genetic methods. On the basis of the results of anti-fungal spectrum against several pathogens by RRj 228, the antagonistic effect of the isolate against Botrytis cinerea, Pythium ultimum, Phytopthola capsici, and Rhizoctonia solani, especially against red-pepper anthracnose caused by Colletotrichum acutatum, was remarkable. The experiment evaluating the biological control effect by RRj 228 revealed that the $ED_{50}$ value by the RRj 228 culture against C. acutatum, R. solani and P. ultimum were 0.14 mg/ml, 0.16 mg/ml and 0.29 mg/ml, respectively. An antagonistic substance was isolated and purified by several chromatographies from the RRj 228 culture. The $^1H$ and $^{13}C$ assignment of the antagonistic substance was achieved from two-dimensional $^1H-^1H$ COSY, HMQC, and HMBC. Finally, the antagonistic substance was identified as Phenazine-1-carboxylic acid ($C_{13}H_8N_2O_2$, M.W.=224).

• Journal of Food Hygiene and Safety
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• v.34 no.6
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• pp.591-594
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• 2019

Some strains of Escherichia coli are categorized as pathogenic bacteria and alternative antimicrobials including bacteriophages for controlling these bacteria have been studied. In this study we screened antimicrobial candidates that present synergistic inhibition of the growth of E. coli DH5α as a model when co-treated with the bacteriophage ECP27 to target the bacteria. As candidates, CaCl₂, lactic acid, and citric acid were tested. CaCl₂ showed a synergistic inhibition against the strain by dose-dependent manner at 6 h of incubation but the viable cell count was recovered at 12 h. However, lactic acid and citric acid at 30 mM concentration showed synergistic inhibitions at 6 h of incubation and cleared the viable cells of E. coli DH5α at 12 h when co-treated with the bacteriophage even though lactic acid or citric acid alone was effective. Therefore, co-treatment using the bacteriophage and organic acids such as lactic acid and citric acid can be a solution for synergistic inhibition of the growth of E. coli.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.125-132
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• 2009

In order to develop probiotics which may be a viable alternative of antibiotic use in pig industry, five bacterial strains (Lactobacillus sp. HN 52, 92, 98, 235 and AP 116) possessing antimicrobial properties were selected from 500 strains isolates of pig intestines. The bacteriocin produced by Lactobacillus sp. HN 235 displayed a relative broad spectrum of inhibitory activity against all Enterococcus strains, Pseudomonas aeruginosa, Listeria monocytogenes and Clostridium perfringens using the spot-on-lawn method. The production of antimicrobial substance started in the middle of the exponential growth phase, reached maximum levels (6,400 AU/mL) in the stationary phase, and then declined. Bacteriocin activity remained unchanged after 30 min of heat treatment at $95^{\circ}C$ and stable from pH 2.0 to 10 for 1 h, or exposure to organic solvents; however, it diminished after treatment with proteolytic enzymes. The molecular weight of the bacteriocin was about 5 kDa according to a tricine SDS-PAGE analysis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.10
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• pp.1466-1470
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• 2009

This study was focused on the development of anticariogenic edible films using pullulan containing grapefruit seed extract (GFSE), polylysine or propolis. According to the result of antimicrobial activity (disc diffusion method) of GFSE, polylysine and propolis against Streptococcus mutans, antimicrobial pullulan film was produced by adding grapefruit seed extract. The optimum combination of pullulan and sorbitol (plasticizer) was 10$\sim$15% (w/v) and 40$\sim$50% of pullulan (w/w), respectively. Minimum concentration of grapefruit seed extract for growth inhibition of Str. mutans was 50 ppm in medium. Formulation of antimicrobial pullulan films containing grape seed extract was established and these results evidently showed potential for commercial application.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1864-1871
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• 2013

The effect of additives on the quality of low salted doenjang was investigated during storage. Amylase activity gradually decreased during storage and protease activity decreased after four weeks. The number of yeast was lower in the mustard or ethanol added groups without a difference in bacterial count. The L- and b-values decreased gradually during storage with lower total color difference (${\Delta}E$) in garlic added doenjang. Gas production was reduced in the ethanol or mustard added groups. Titratable acidity and acid values were low in the ethanol and ethanol-garlic added ones. A reducing sugar content was higher in the groups with added additives. Ethanol decreased to the largest extent in mustard added doenjang. Amino-type nitrogen decreased in ethanol added doenjang, whereas ammonia-type nitrogen was low in the ethanol or mustard added groups. The taste, flavor, and overall acceptability of doenjang were significantly higher in the ethanol or garlic added groups than in the other groups.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.47-53
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• 2007

The DY1 strain of Gram-positive, rod-shaped bacteria was isolated from the soil sample collected from Daeam mountain, Korea. The culture filtrate of DY1 strain showed a broad spectrum of antimicrobial activity on various pathogenic and food poisoning enteric bacterial species tested in vitro. It showed significant growth-inhibitory effect on Salmonella enterica sp., Shigella sp., pathogenic Escherichia coli, Vibrio cholerae, Vibrio parahemolyticus, and Yersinia enterocolitica. For the identification of the DY1 strain, morphological, biochemical and molecular phylogenetic approaches were performed. The DY1 strain was found to be a member of the genus Paenibacillus on the basis of morphological and biochemical analyses. The 16S rDNA of DY1 showed the highest pairwise identity with Paenibacillus polymyxa with 99.79% (1,413 bp/1,416 bp). The antimicrobial entity from DY1 looked different from preciously reported ones and seems to have a great potential to be further studied as a candidate of new antibiotics to control multi-drug resistant pathogens.