• Journal of Ginseng Research
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• 제17권2호
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• pp.148-152
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• 1993

One kind of microorganism was isolated and identified from Korean fresh, white and red ginseng, and the effect of a preservative, sodium benzoate on the microorganism and its thermal resistant propertues were studied. The results obtained were as follows. The predominant strain on ginseng and ginseng products was identified as Penicillium sp. The strain showed perithecium structure producing ascospores. The growth of the strain was slightly inhibited at 0.0571 concentration of sodium benzoate. The minimal inhibitory concentration (MIC) of sodium benzoate against the strain was 0.26%. The D value of the strain at 56, 59, $62^{\circ}C$ were 9.9, 5.0 and 4.5 min, respectively.

• 대한수의학회지
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• 제26권1호
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• pp.79-85
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• 1986

This paper deals with the isolation of Salmonella on 3 herds during the period from May 1984 to May 1985. Isolated Salmonella were examined for serotypes, adhesive fimbriae, antibiotic susceptibility and detection of R plasmid. The results were as follows; Of total 1505 cattle, 24 Salmonella were isolated from 18 cattle (1.2%) and their serotypes were S. enteritidis (9 strains), S. derby(4 strains), S. infantis (1 strain), $C_1$ group(8 strains), $C_2$ group(1 strain) and untypable(1 strain). Twelve strains of Salmonella were isolated from 227 cattle with diarrhea and their serotypes were S. enteritidis(4 strains), S. derby(3 strains), S. infantis(1 strain), $C_1$ group(3 strains) and untypable(1 strain). The isolation rate of Salmonella in cattle varied from 1.6 to 0.9% in 3 herds, it was higher in summer and autumn and lower with the age. Of total 24 strains, 23 were adhesive type 1 fimbriae. Antibiotic susceptibility test of Salmonella isolated was performed by the agar dilution method, using 9 antibiotics as follows: ampicillin(Am), chloramphenicol(Cm), gentamicin(Gm), kanamycin(Km), nalidixic acid(Na), rifampicin(Rf), streptomycin(Sm), sulfadimethoxine(Su) and tetracycline(Tc). All the strains tested were susceptible to Am, Cm, Gm, Km, Na, Rf and Tc. Of total 24 strains, 23(95.8%) were resistant to Su and 14(58.3%) to Sm. Of the 23 resistant Salmonella strains, all the strains were found to carry R plasmid. Among them, two strains which had the R plasmid conferring SmSu resistance was transferable at $25^{\circ}C$ only.

• 한국식품영양학회지
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• 제27권2호
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• pp.213-218
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• 2014

적리를 동반하는 돼지 분변에서 용혈성 균주를 분리 동정한 후, 장 독소 생성 유 무 및 항생제 감수성 시험을 수행하였다. 분리된 용혈성 균주 B. cereus BY06의 gyrB 유전자 염기서열을 분석한 결과, B. cereus와 99% 유사성을 나타내었다. PCR법에 의한 장 독소 유전자 검출 시험에서 B. cereus BY06는 장 독소 분비 양성으로 판정됨에 따라 설사형 식중독 균임이 확인되었다. B. cereus BY06를 이용한 항균제의 감수성 시험 결과, penicillin G에는 내성을 나타낸 반면 cephalothin, vancomycin, clindamycin, fusidic acid, gentamicin, ciprofloxacin, tetracycline 및 rifampin에 대하여 감수성을 나타냈다. 본 연구를 통해 돼지 분변에서 분리된 B. cereus 균주는 설사를 유발하는 장 독소를 분비하며, penicillin G에 대한 내성을 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제34권5호
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• pp.1040-1050
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• 2024

To isolate and analyze bacteria with Verticillium wilt-resistant properties from the fermentation residue of kitchen wastes, as well as explore their potential for new applications of the residue. A total of six bacterial strains exhibiting Verticillium wilt-resistant capabilities were isolated from the biogas residue of kitchen waste fermentation. Using a polyphasic approach, strain ZL6, which displayed the highest antagonistic activity against cotton Verticillium wilt, was identified as belonging to the Pseudomonas aeruginosa. Bioassay results demonstrated that this strain possessed robust antagonistic abilities, effectively inhibiting V. dahliae spore germination and mycelial growth. Furthermore, P. aeruginosa ZL6 exhibited high temperature resistance (42℃), nitrogen fixation, and phosphorus removal activities. Pot experiments revealed that P. aeruginosa ZL6 fermentation broth treatment achieved a 47.72% biological control effect compared to the control group. Through activity tracking and protein mass spectrometry identification, a neutral metalloproteinase (Nml) was hypothesized as the main virulence factor. The mutant strain ZL6ߡNml exhibited a significant reduction in its ability to inhibit cotton Verticillium wilt compared to the strain P. aeruginosa ZL6. While the inhibitory activities could be partially restored by a complementation of nml gene in the mutant strain ZL6CMߡNml. This research provides a theoretical foundation for the future development and application of biogas residue as biocontrol agents against Verticillium wilt and as biological preservatives for agricultural products. Additionally, this study presents a novel approach for mitigating the substantial amount of biogas residue generated from kitchen waste fermentation.

• 방사선산업학회지
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• 제17권2호
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• pp.183-190
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• 2023

The global problem of handling radioactive materials is facing limitations. Eco-friendly bioremediation methods using microorganisms are being studied. This study was conducted to screen cesium-resistant microbial strains. M1 strain was selected from the soil sample by enriched culture in R2A medium containing 100 mM CsCl. In liquid medium containing above 40 mM of CsCl, the growth of M1 was inhibited in a concentration-dependent manner. Otherwise, M1 can survive up to 80mM CsCl in solid medium although the growth rate was slow and colony size was small. M1 strain was genetically identified as a strain of the genus Acinetobacter through 16S rRNA sequencing, and radiation resistance (D10 value) of M1 was found to be 0.307 kGy. These results showed that M1 strain is highly resistant to cesium and can grow in radiation environment. It was considered that M1 strain is useful in the field of biological decontamination of cesium.

• 농약과학회지
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• 제2권2호
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• pp.75-82
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• 1998

벼멸구의 카보후란에 대한 저항성 기작을 구명하기 위해 실내에서 카보후란으로 30세대 도태하여 얻은 저항성계통($LD_{50};\;20.3{\mu}g/g$)과 약제를 12년 동안 처리하지 않은 벼멸구 감수성 계통($LD_{50};\;0.3{\mu}g/g$)에 $^{14}C$-카보후란을 처리하여 계통 간 대사물 량의 차이를 조사한 바 카보후란의 대사물인 benzofuran과 TLC의 의해 전개되지 않은 원점 부분은 감수성 계통에서 많았으며, 대사되지 않은 카보후란은 저항성 계통에서 많았다. 이러한 경향은 처리 후 1, 3시간 대사에서도 같은 경향이었다. 이상의 결과로부터 저항성 벼멸구에서 가수 분해 효소의 일종인 에스테라제가 저항성이 발달함에 따라 에스터 결합을 끊는 역할에서 카보후란과의 결합체 역할로 그 기능이 전환되는 것으로 생각되며 이것이 저항성 기작 중 주요한 하나의 요인으로 사료된다. 산화효소와 전이효소는 저항성과 감수성 계통에서 대사물의 양에 차이가 없어 저항성과는 무관한 것으로 생각된다.

• 한국환경과학회지
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• 제6권3호
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• pp.249-258
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• 1997

Mercury- and cadmium-resistant bacteria were Isolated from an Industrial complex wastewater of Taejon area. All of them were motile, gram negative rods. In the results of physicochemical test and VITEK card test. HM1 was Identified with Achetobacter cd- coaceucus, CM3 was Identified 65 Commonas acidovorns, HM2, HM3, CMI , and CM4 were Pseudomonas sp., but HM4 and CM2 were unidenteed. They were tested for subceptlbility to 14 heavy metals. Mercury-resistant bacteria(HM1, HM2, HM3, and HM4) were sensitive to low concentration(100~400ppm) of $Cd^{2+}$, $Co^{2+}$. $Zn^{2+}$, and Ni2+, while cadmium-resistant bacteria(CM1, CM2, CM3, and CM4) showed resistance up to the high concentration(600~ 1, 200ppm) of these metal loons. As a result of resistance spectrum test of mercury-resistant bacteria, HM1 was broad-spectrum strain, HM2. HM3, and HM4 were narrow-spectrum stratas. Transmission electron microscopic examination of cell wall of HM1 culture grown with and without 100ppm of $HgCl_2$ showed remarkably merphological abnormalities. In the result of atomic absorption spectrometric analysis of cadmium-resistant bacteria grown at 200ppm of $CdCl_2$ for 6h, all of them accumulated cadrnium(14ppm~57ppm) In cell. In cadinium-resistant bacteria, CM1, CM2, and CM4 were spared from the Inhibitory effect of $Cd^{2+}$ by the addition of $Mn^{2+}$, CM4 were also spared from the Inhibitory effect of $Cd^{2+}$ by the addition of $Mn^{2+}$ as well as $Zn^{2+}$.

• 한국환경보건학회지
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• 제29권2호
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• pp.94-102
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• 2003

This study was carried out to investigated the distribution and characteristics of Vibrio spp. isolated from fish and shellfish, seawater and brackish water samples collected from Pohang, Uljin, Yeongduk and Gyeongju in Gyeongbuk Province from April 2000 to October 2000. Total 155 strains of genus Vibrio were isolated from 439 collected samples, and numbers of isolated strains of V. parahaemolyticus and V. vulnificus were 140 and 15, respectively. The isolation rate from the samples collected in Pohang was the highest as 41.5% (76 strains), and wat the highest as 71.4% (30 strains) in brackish water, and was the highest as 55.7% (34 strains) in August. And the optimal pH, temperature, and NaCl concentration for growth of V. parahaemolyticus and V. cholerae were 8.0, 3$0^{\circ}C$ and 2.0％, respectively. In a resistance test for environmental factors, heat and cold resistants of V. parahaemolyticus were higher than those of V. vulnificus, withstanding for 15 minutes at 6$0^{\circ}C$ and 6 days at -18$^{\circ}C$. The pH range for existence of V. parahaemolyticus and V. vulnificus were 4.5~l1.0 and 4.5~10.0, showing the similar resistance to pH. V. parahaemolyticus and V. vulnificus could grow in media containing up to 10.0% and 7.0% NaCl, respectively, Salt-tolerance of V. parahaemolyticus was higher than that of V. vulnificus. In an antibiotics sensitivity test against 16 strains of V. parahaemolyticus, twelve strains were resistant to ampicillin, eight strains were resistant to cephalothin. one strain was resistant to streptomycin, and one strain was resistant to ticarcillin.

• 대한미생물학회지
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• 제21권3호
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• pp.381-385
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• 1986

Twenty strains of penicillin(PC)-resistant Staphylococcus aureus ($MIC{\geqq}32U/ml$) were chosen randomly from recent isolates and submitted to the present experiment to see what effect the combined antibiotic action of moxalactam(MX) and fosfomycin(FM) would bring about on the cells, using MS-2 system. 1. The conventional agar dilution method and the rapid automatic MS-2 system were used in measuring the MICs of MX and FM against each strain and the comparison of the data obtained revealed no significant difference between the two methods in the titer and distribution of the MICs. 2. The automatic MS-2 system was, therefore, used alone in determining the combined growth inhibitory effect of MX and FM because of its more rapidness, and the obtained results were that most of the PC-resistant strains(16 out of 20, 80%) were synergistically inhibited by the two antibiotic combination while additive effect was observed in the remaining 4 strains(20%). 3. Thus, it is suggested that the growth of PC-resistant staphylococcal cells may be synergistically inhibited by MX and FM combination and the efficiency of two antibiotic action as well as MIC of single antibiotic may be more rapidly determined by the MS-2 system than by the conventional method.

• 대한수의학회지
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• 제20권2호
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• pp.159-165
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• 1980

A total of 98 strains of Bordetella bronckiseptica isolated from pigs affected the infectious atrophic rhinitis(AR) during 1978 were surveyed for drug sensitivity to 26 chemotherapeutic agents, and minimum inhibitory concentration(MIC), incidence rate of resistant strain and resistant patern from the strains which were obtained from the different pig farm in Jeonnam province were examined. The results obtained are summarized as follows. 1. Most of the strains tested were resistant to Ampicillin (AB, PC), spiramycin(SPO, sulfa drugs (SD) (MIC:$400.0{{\mu}g/ml}$) and streptomycin(SM) (MIC:$200.0{{\mu}g/ml}$). Of the 75.0% of strains were also resistant to penicillin(PC) (MIC:$200.0{{\mu}g/ml}$) and of the 14.3 of strains were inhibited to grow to tetracycline(TC), chlortetracycline(CTC), oxytetracyc-line(OTC), erythromycin(EM), tylosin(TS), leucomycin (LM) and chloramphenicol (CP) (MIC:$6.25{{\mu}g/ml}$). On the other hand, most of the strains tested were inhibited to grow to kanamycin(KM), gentamycin(GM) neomycin(NM) (MIC:$25.0{{\mu}g/ml}$) and to colistin(CL) (MIC:$12.5{{\mu}g/ml}$). 2. Incidence rate of resistant strains to main chemotherapeutic agents was 100.0% of sulfa drugs, 96.4% of streptomycin, 85.7% of penicillin, tetracycline, chloramphenicol and erythromycin, 46.4% of gentamycin, 17.9% of colistin and 0.0% of kanamycin and nalidixic acid.