• Journal of Life Science
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• v.11 no.3
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• pp.266-272
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• 2001

A total of 79 Salmonella spp. were isolated from Pusan area in 2000. The serotypes of 79 Salmonella isolates were classified as 42 strains of S. typhi(53.1%), 24 strains of S. enteritidis(30.4%), 9 strains of S. montevideo(11.4%), 2 strains of S. typhimurium(2.5%), 1 strain of S. infantis(1.3%) and 1 strain of S. indiana(1.3%) strains(16.5%) of Salmonella sp. were isolated at May July, respectively. The isolates of S. typhi were sensitive to most sntibiotics except streptomycin. All isolates of S. typhi were especially sensitive to tobramycin, gentamicin, colistin, kanamycin, samikacin, sulfamethozazole/ trimethoprim, cefriaxone, ceftazdime, cifrofloxacin, cefoxitin and cefotaxime. Isolates of S. enteritidis wer presented higher resistance than isolates of S. typhi. Twenty-four strains of S. enteritidis were sensitive to kanamycin, amikacin cifrofloxacin, cefoxitin and cefotaxime, however 13 strains(54.2%) of S. enteritidis were resistant to carbenicillin, ampicillin and ticarcillin. Nine strains of S. montevideo were sensitive to most antibiotics except carbenicillin and streptomycin. Each 1 stain of S. indiana and S. infantis was sensitive to most antibiotics used in this study except streptomycin. Three kinds of resistant pattern (CB, SM, TE, AM, TC). In the case of S. enteritidis isolates, 9 kinds resistant pattern were detected. Most frequent resistant pattern of S. enteritidis isolates was CB, AM, TC type(16.7%)

• The Journal of the Korean Society for Microbiology
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• v.12 no.1
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• pp.1-10
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• 1977

40 strains of E. coli isolated from residents of a doctorless area in Korea in 1976 and 40 strains of E. coli isolated from patients of Seoul National University Hospital from 1975 to 1976 were examined for susceptibilities to 14 antimicrobial agents by the agar dilution method. The susceptibilities of the two groups to each antimicrobial agent were compared and correlations in the antimicrobial susceptibility of the 80 strains of E. coli among the 14 antimicrobial agents were also analyzed. The results were obtained as follow: 1. With Tetracycline, Oxytetracycline, Doxycycline and Ampicillin, the mean MIC's of E. coli isolated from patients of Seoul National University Hospital were 8.6 to 14 times higher than. those of E. coli isolated from residents of a doctorless area. 2. With Streptomycin, Minocycline and Carbenicillin, the mean MIC's o{ E. coli isolated from patients of Seoul National University Hospital were 4.1 to 5.6 times higher than those of E. coil isolated from residents of a doctorless area. 3. With Kanamycin, Penicillin and Cotrimoxazole, the mean MIC's of E. coli isolated from patients of Seoul National University Hospital were 2.6 to 3.7 times higher than those of E. coli isolated from residents of a doctorless area. 4. There were no significant differences in susceptibility to Erythromycin respectively between E. coli isolated from patients of Seoul National University coli isolated from residents of a doctorless area. 5. E. coli isolated from patients of Seoul National University Hospital were resistant to Erythromycin(100%), Streptomycin(75%), Tetracycline(72.5%), Oxytetracycline(72.5%), Doxycycline(72.5%), Minocycline(67.5%), Penicillin(82.5%), Ampicillin(60%) and Carbenicillin(65%) respectively and were sensitive to Gentamicin(97.5%), Cephalexin(92.5%) and Kanamycin(72.5%) respectively. 6. E. coli isolated from residents of a doctorless, area were resistant to Erythromycin(100%), Streptomycin(40%) and Penicillin(50%) respectively and were sensitive to Gentamicin(100%), Kanamycin(92.5%), Tetracycline(87.5%), Oxytetracycline(87.5%), Doxycycline(87.5%), Minocycline(87.5%), Ampicillin(95%), Carbenicillin(92.5%) and Cephalexin(97.5%) respectively. 7. There were high correlations among the suscebtibilities of the 80 strains of E. coli to Tetracycline analogues(Tetracycline, Oxytetracycline, Doxycycline and Minocycline) and among susceptibilities of the 80 strains of E. coli to Penicillin analogues(Penicillin, Ampicillin and Carbenicillin). 8. There were relatively high correlations between the susceptibilities of the 80 strains of E. coli to Penicillin analogues and those to Tetracycline analogues, between the susceptibilities to Penicillin analogues and those to Streptomycin and between the susceptibilities to Tetracycline analogues and those to Streptomycin.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.508-513
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• 2010

Ninety three strains (4.2%) of Vibrio parahaemolyticus were isolated from 2,239 samples of commercial marine products during 2006-2008 in Seoul, Korea. We examined 16 antimicrobial susceptibilities of 93 V. parahaemolyticus isolates. Antibiotic resistance of V. parahaemolyticus was most frequently observed to ampicillin (93.5%), followed by cephalothin (90.3%), streptomycin (87.1%), ticarcillin (55.9%), and amikacin (40.9%). Antibiotic susceptibility was most frequently observed to nalidixic acid, chloramphenicol and ampicillin/sulbactam (100%), followed by trimethoprim/sulfamethoxazole (98.9%), gentamicin and tetracycline (82.8%), and ceftriaxone (63.4%). In addition, the isolates also displayed intermediate resistance to kanamycin (79.6%), ciprofloxacin (64.5%), amikacin (47.3%) and cefoxitin (43.0%). All isolates were resistant to more than two drugs. The most prominent multiple drug resistance was 3 drug resistance (37.6%), followed by 4 drug (24.7%), 5 drug (17.2%), and 6 drug resistance (11.8%). The most prominent multiple drug resistance pattern was the cephalothin-streptomycin-ampicillin resistance pattern (22.6%), followed by cephalothinticarcillin-streptomycin-ampicillin (18.3%) and cephalothin-ticarcillin-streptomycin-ampicillin-amikacin (9.7%). Multiple drug resistance patterns of V. parahaemolyticus from marine products require continuous monitoring.

• Journal of Life Science
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• v.8 no.1
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• pp.40-50
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• 1998

Staphylococuus aureus and Escherichia coli is increasingly responsible for outbreaks of nosocomial infection around the world. Because serious infections due to these organisms currently necessiate use of non-$\beta$-lactam antimicrobial therapy and because strains is ofen resistant to many antimicrobial agents, infections with this organism are difficult to treat. Isolated strains from post operaton wounds of PNU hospital patient were tested for the antimicrobial susceptibility, resistant pattern and combined action to the 6 antibiotics. The minimal inhibitory concentraction of each antibiotic anc antibiotics combining in various ratios were measured by checkerboard dilution method. the synergism was determined through calculating the fractional inhibitory concentraction index (FICI). In case of S. aureus, 15 strains was shown to be highly sensitive to streptomycin and 13 strains to cephalothin. In case of E. coli, it is excellent senstitive 16 strains, sensitive 4 strains on cefoperazone, as like S. aureus, and thus the sensitive is most to be 66%. As the result of gaining MIC from S. aureus upon agar dilution method, MIC$_{50}$ was 8$\mu$g/ml, MIC$_{90}$ was 16$\mu$g/ml and thus the streptomycine is shown to be lowest. In case of E, coli, S. MIC$_{50}$ was 4$\mu$g/ml, MIC$_{90}$ was 16$\mu$g/ml, in streptomycin and thus is shown to be lower than S. aureus. As the result of comparing the resistance aspect of combining the antibiotics on S. aureus and E. coli, the resistant strain can be known to be reduced to the large range more than each 40% than combining with only aminoglycoside-series or cephalosporine-series. As the result of combining aminoglycoside-series, streptomycin and cephalothin or cefuroxime sensitive to S. aureus and E. coli in the above mentioned results, the increase or imporovement of effect is over 73% and 80%, respectively, thus the case od combining 2 antibiotics is shown to be better in the effect. Isolated strains from operating wounds were for the antimicrobial susceptibility. In case of S. aureus 15 strains was shown to be sensitive very much on streptomycin. In case of E. coli it is excellent sensitive 16 strains. As the results of combining aminoglycosides-series, streptomycin and cephalosporine series, cephalothin and cefuroxime, the increase or improvement of effect is over 73%, thus case of combining 2 antibiotics is shown to be better in the effect.

• Research in Plant Disease
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• v.29 no.2
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• pp.168-173
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• 2023

Agricultural antibiotics are widely used to inhibit the growth of phytopathogenic bacteria involved in plant diseases. However, continuous antibiotic overuse in crop production may lead to the development of antibiotic resistance in phytopathogenic bacteria. This study was conducted to evaluate the resistance to three different agricultural antibiotics (oxytetracycline+streptomycin, streptomycin, and validamycin A) in 91 strains of phytopathogenic bacteria including Pectobacterium carotovorum, Pseudomonas syringae pv. actinidiae, Clavibacter michiganensis subsp. michiganensis, C. michiganensis subsp. capsici, and Xanthomonas arboricola pv. pruni. Bacterial growth in the presence of various concentrations of validamycin A was also assessed spectrophotometrically by analyzing the optical density. All strains did not grow when the cells were exposed to oxytetracycline+streptomycin or 100× of streptomycin. However, among the 91 strains, 4% and 2% strains showed bacterial growth at the concentrations of 1× and 10× of streptomycin, respectively. Furthermore, 97%, 93%, and 73% strains were resistant to the 1×, 10×, and 100× of validamycin A, respectively, and especially, P. carotovorum contained the highest resistance to the validamycin A. Minimum bactericidal concentration values of validamycin A did not correlate with the patterns of agricultural antibiotic resistance. Further studies are needed to understand the incidence and development of antibiotic resistance in phytopathogenic bacteria.

• Korean Journal of Pharmacognosy
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• v.22 no.1
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• pp.45-50
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• 1991

The combined effect of berberine isolated from the bark of Phellodendron amurense and some antibiotics was evaluated in order to measure the antibiotic activities. In this study, in the presence of streptomycin, tetracycline, cephradine as antibiotics, Staphylococcus aureus, Escherichia coli, Shigella sonnei as microorganisms were grown in an Automated Microbiology System. In case of Staphylococus aureus, combination with berberine and cephardine resulted in the strongest synergistic activity and in case of Escherichia coli and Shigella sonnei, combination with berberine and streptomycin resulted in the strongest synergistic activity. The combination with berberine and antibiotics increased the antibiotic activities, thereby showing a synergistic action.

• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.150-155
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• 1996

1993년과 1994년에 걸쳐 한국의 고추 재배 지역에서 분리한 고추 더뎅이병균은 66개의 균주중 24개가 race 1이었으며, 나머지는 42균주가 race 3이었다. Race 2균주는 발견되지 않았다. 총 66개의 균주중 8%가 200 $\mu\textrm{g}$/ml의 황산구리에 저항성을 보였으며, 100 $\mu\textrm{g}$/ml의 streptomycin sulfate에는 단지 한 균주만이 저항성을 나타냈다. Race 1균주중 21%가 구리에 저항성을 보였으나 race 3균주는 모두 구리에 감수성을 나타냈다. 모든 감수성 균주는 구리 농도 1 $\mu\textrm{g}$/ml에서 죽거나 아주 낮은 수준만이 생존하였으나 저항성 균주는 128 $\mu\textrm{g}$/ml에서도 생존하였다.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.86-90
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• 2003

Little is known to data about the in vitro activity of antimicrobial agents aganist Brucella cams (B cams) isolated from Korea. Our study aimed at determining the in vitro activities of 15 antimicrobial agents against 3 isolates and 52 isolates of B cams from dogs in 1994 and 2002, respectively. In minimal inhibitory concentration (MIC) study, minocycline and doxycycline showed the lowest MICs ( < 0.06-0.5 ug/ml). Gentamicin, streptomycin, ciprofloxacin, norfloxacin and rifampin showed MICs in the range of less than 1 ug/ml. Lincomycin and sulfisox azole showed the highest MICs ( > 32 ug/ml). Interestingly, MICs of macrolides (erythromycin, spiramycin, tylosin) against 52 isolates in 2002 were 16-64 times higher than that of 3 isolates in 1994. In minimal bactericidal concentration (MBC) study, gentamicin, streptomycin, ciprofloxacin and norfloxacin showed the lowest MBCs [0.12-1 ug/ml (1-2 times higher than MIC)], but minocycline and doxycycline showed the highest MBCs [8-32 ug/ml (128 times higher than MIC)]. Rifampin showed the MBCs in the range from 2 to 4 ug/ml (2-4 times higher than MIC).

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.429-432
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• 1991

In order to prepare probiotics, a strain which has resistant against acid, bile salts and antibiotics was isolated from infant and anirnat feces. Among these isolated strains, TK- 19 showed a strong acid tolerance and growth at 500 $\mu g$/ml of Na-deoxycholate. Also strain TK-19 was resistant to kanarnycin (30 $\mu g$/ml), streptomycin (10 $\mu g$/ml), nisin (50 $\mu g$/ml) and tetracycline (10 $\mu g$/ml). The isolated strain TK-19 was identified as Streptococcus faeciam, and was named Streptococcus faeciurn TK-19.

• Journal of Plant Biotechnology
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• v.33 no.2
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• pp.75-84
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• 2006

Heteroplasmic rice plastid transformant was generated using suspension cells as bombardment materials. PCR analyses confirmed incorporation of aadA and cp4-epsps genes into the rice plastid genome by homologous recombination events via the flanking sequences of the trnI and trnA. Transplastomic calli were actively proliferated when cultured on AAM2 medium supplemented with various concentrations (500-3000 mg/L) of streptomycin in dark condition, and transplastomic suspension cells showed resistance to nonselective herbicide, glyphosate. Through 'agarose pie selection' method, heteroplastomic calli, containing considerably high level of transplastome and expressing the CP4 EPSPS protein, were obtained. They were further regenerated to green shoots with healthy roots.