• Journal of Microbiology and Biotechnology
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• 제33권1호
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• pp.35-42
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• 2023

This study aimed to identify the therapeutic ability of a novel toll-like receptor (TLR) 5 agonist, KMRC011, on ulcerative colitis induced by Citrobacter rodentium and dextran sulfate sodium in a C57BL/6N mouse model. Ulcerative colitis was induced in the mice by the oral administration of 1% dextran sulfate sodium in sterile drinking water for seven days ad libitum, followed by C. rodentium infection on the seventh day by intra-gastric administration (DSS-CT group). KMRC011 was administered intramuscularly at both 24 h and 15 min before (Treatment 1 group), and at both 15 min and 24 h after (Treatment 2 group) the C. rodentium infection. The length of the large intestine and histopathological counts were significantly greater and mucosal thickness was significantly thinner in the Treatment 1 group compared to the DSS-CT and Treatment 2 groups. Il-6 and Il-10 mRNA expression levels were upregulated, while Ifn-γ and Tnf-α mRNA expression levels were significantly downregulated in the Treatment 1 group, compared to the DSS-CT group. NF-κB p65 expression level was elevated due to ulcerative colitis in the DSS-CT group, but was significantly downregulated in the Treatment 1 group. Overall, KMRC011 showed protective effects against murine colitis by inhibiting NF-κB signaling.

• 대한환경공학회지
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• 제27권12호
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• pp.1298-1304
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• 2005

Citrobacter Amalonaticus strain JB101을 이용하여 과염소산염과 질산염이 동시에 존재할 때 두 전자수용체 간의 경쟁특성을 파악하고, MBR(membrane bioreactor)을 이용한 과염소산염 처리 가능성을 검토하였다. 과염소산 및 질산염에 대한 strain JB101의 비성장속도는 각각 0.27 및 0.58 $hr^{-1}$, 최대기질이용속도는 각각 35.1 mg $ClO_4^-/g$ protein-day 및 45.6 mg $NO_3^-/g$ protein-day이었다. 질산염은 과염소산염에 대한 경쟁적 저해제이었으며, strain JB101은 과염소산보다는 질산염을 전자수용체로 선호하였다. 유입 과염소산염 농도가 20 mg/L이였던 HCMBR에서는 막 면적당 부하 4.6 g $ClO_4^-/m^2-day$까지 과염소산염의 제거효율이 100%이었으나, 질산염 5 mg/L를 첨가하자 질산염은 완전히 제거되었으나 과염소산염 제거효율이 96.5%로 감소하였다. 유입 과염소산염 농도가 0.7 mg/L이였던 LCMBR에서는 부하 0.23 g $ClO_4^-/m^2-day$까지 과염소산염의 제거효율이 100%이었다. 두 MBR 모두 높은 부하에서는 막의 막힘현상이 문제로 제기되었다. 과염소산염에 대한 아세트산염 소모비는 LCMBR의 경우 $13.7{\sim}51.7$로 HCMBR의 $2.5{\sim}3.6$보다 높았으며, 이는 아세트산염이 산소를 전자수용체로 이용하여 소모되었기 때문이다. 따라서 전자공여체 첨가량은 유입수에 포함된 다른 전자수용체의 농도를 고려하여 결정하여야 한다.

• 한국식품위생안전성학회지
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• 제12권4호
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• pp.294-299
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• 1997

A study was conducted to determine contamination status of fish sold at wholesale market in Seoul. A total of 79 samples (35 different kindry fish) were collected from the wholesale market. E. coli and coliform group bacteria were cultured and tested for sensitivity against antibiotics. The results are summarized as follows; 1. E. coli was isolated from 23 out of 79 samples (29.1%), and coliform groups from 53 out of 79 (67.1%). 2. Of coliform group, Citrobacter freundii was the most common and Enterobacter clacae was the next. 3.23 E. coli strains isolated from fishes were resistant to Oxacillin, Erythromycin and Lincomycin, meanwhile 23 E. coli strains were sensitive to Cefoperazone, Ceftazidime, Imipenem, and Ciprofloxacin.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 추계학술대회
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• pp.19-25
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• 1997

Bicyclomycin(BCM)은 1972년에 일본 Hokkaido, Sapporo지방의 토양균중의 하나인 Streptomyces Sapporoneosis의 배양액으로부터 최초로 분리된 항생물질로서 특히 Gram(-) 박테리아인 Escherichia coli. Klebsiella, Shigella, Salmonella, Citrobacter, Enterobacter cloacae, Neisseria gonorrhoeae등에 대한 선택적인 항균효과를 가지고 있고 Streptomycin, Kanamycin, Chloramphenicol, Tetracyclin, Aminobenzylpenicillin 및 naldixic acid 등에 대해 교차내성을 가지고 있지 않다. BCM은 구조적인 면에서 [4.2.2]bicyclic구조를 가지고있는 특이한 항생물질로서 C(1)-triol부분, diketopiperazine부분 그리고 C(5)-C(5a)exomethylene의 3 부분으로 크게 나눌수 있다(Fig. 1). BGM은 E. coli에 대한 항균력으로서 250-500 $\mu\textrm{g}$/mL의 MIC value를 가지고 있고 급성독성으로서 LD$_{50}$가 4g/kg 이상으로 거의 독성이 없는 것이 특징이다. 현재 Fujisawa pharmaceutical Ltd.로부터 Bicozamycin이라는 상품명으로 설사치료제 용도로 시판되고 있다.

• 미생물학회지
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• 제17권2호
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• pp.49-57
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• 1979

Cadimium ion-resistant microorganism was isolated from the sludge of wastewater. The physiological, morphological and other cultural data showed that this strain belonged to Citrobacter freudii. A clearcut distinction of growth among nutrient broth, typtic soy broth and synthetic medium was demonstrated. The resistant cells showed only slight mutagenic action. During the growth of bacterial population in resting state, the organisms reduced the initial level of resistance to cadmium ions when they were not kept in contact with cadmium ions in bacteral multiplication. And cadmium ion-resistant and cadmium ion-sensitive strain were found to show equal, lower or higher sensitivity to other heave metals.

• 한방안이비인후피부과학회지
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• 제17권1호
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• pp.126-130
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• 2004

Objectives; Bioassay-directed fractionation of the dried roots of Salvia miltiorrhiza led to the isolation of abietane tanshinones, crptotanshinone and dihydrotanshinone. Methods: Their structures were elucidated using 1H-and 13C-NMR, UV, IR and mass spectral analysis. Result and Conclusions : These compounds exhibited a moderate antimicrobial activities against Staphylococcus epidemidis, Staphylococcus aureus, Staphylococcus pyogene. Actinobacillus actinomycetemcomitans, Escherichia coil, Enterbacter cloacae, Pseudomonas aeruginosa, Citrobacter freundii, and Samonella typhimurium.

• 한국미생물·생명공학회지
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• 제24권2호
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• pp.222-226
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• 1996

The enzymatic synthesis of 3, 4-dihydroxyphenyl-L-alanine (L-DOPA) was examined for the effects of the reaction additives such as sodium borate, alcohol, and organic solvents. The enzyme used was tyrosine phenol-lyase of Citrobacter freundii KCTC 2006 produced in Escherichia coli. The amounts of tyrosine phenol-lyase and pyridoxal-5-phosphate were optimized to 2.0 units/ml and 0.1 mM, respectively, for the synthetic reaction. Sodium borate, a substance that forms a complex with pyrocatechol, reduced the enzyme deactivation by pyrocatechol although it seriously inhibited the enzyme activity. Among the organic solvents tested, dimethylsulfoxide, dimethylformamide, and alcohol increased the productivity of the L-DOPA synthesis. In a reaction system with 5% methanol, L-DOPA concentration increased up to 210 mM after 24 hours, and 77.1% of which was separated as precipitates. The L-DOPA was purified to 99.96% by solubilizing and recrystallyzing the precipitates.

• Archives of Pharmacal Research
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• 제21권5호
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• pp.527-530
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• 1998

The antibacterial activity of novel ${\beta}$-lactamase inhibitors, 6-exomethylene penamsulfones (CH1240, CH2140), has been compared in vivo with that of sulbactam and clavulanic acid against b-lactamase producing strains. In vivo microbiological assessment was used as experimental mouse infection model by gram negative strains. Against Pseudomonas aeruginosa F0013, cefoperazone/CH 1240 was slightly less active than sulbactam. ampicillin/CH 2140 was less effective than sulbactam against escheriachia coli 3457. Especially against Citrobacter diversus 2046E, amoxicillin/CH 2140 was the most potent and amoxicillin/CH 1240 was slightly more active than clavulanic acid. consequently the difference in efficacy between the drug combinations appers to be related to the degree of protection afforded the animals by the b-lactamasse inhibitors. CH1240 and CH2140 are promising new agents and should undergo further investigations.

• 한국임상수의학회지
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• 제37권1호
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• pp.57-59
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• 2020

A 3-year-old, captive female river cooter was presented with a 4-day history of progressive unilateral swelling of the right side of the head, lethargy, and anorexia. History, physical examination, and radiographic examination revealed an aural abscess. After administration of antibiotics and supportive care, surgical intervention was performed. Swab samples were collected from the tympanic cavity during surgery for cytology and antimicrobial susceptibility testing. Molecular analyses of 16S ribosomal RNA gene sequences identified Citrobacter spp. and Morganella morganii. The patient was treated with ciprofloxacin and meloxicam and recovered after 2 months. This report describes the successful correction of a unilateral aural abscess that responded well to surgical intervention and a properly selected antibiotic.

• 원예과학기술지
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• 제28권5호
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• pp.871-876
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• 2010

자생허브 및 도입허브를 몇 가지 선발하여 추출물의 DPPH에 대한 전자공여능으로 항산화 활성과 배지 희석법으로 장내세균과 부패세균에 대한 항균활성을 분석하였다. 선발된 허브는 백리향, 구절초, 삼백초 등 7종의 자생허브와 로즈마리, 케모마일 등 4종의 도입허브로 삼백초를 제외한 대부분이 꿀풀과와 국화과에 속하였다. 또한 대부분이 다년초로서 실생과 삽목방법에 의해 번식하며, 7-10월에 걸쳐 개화하고 식용, 약용, 향료 등으로 이용되었다. DPPH를 이용한 전자공여능을 측정한 결과 자생허브는 69.7-78.7%의 범위에서 평균 74.21%를 나타냈으나 도입허브는 67.4-75.4%의 범위에서 평균 70.67%로 도입허브보다는 자생허브에서 3.54% 높았다. 자생허브 중에는 배초향 78.7%, 삼백초 77.8% 등의 전자공여능이 높았으며, 서양허브 중에는 케모마일이 75.4%로 가장 높았다. 장내세균과 부패세균에 대한 항균활성으로 Gram positive인 $Enterococcus$ $faecalis$에 항균활성 효과가 있는 허브 추출물은 구절초, 삼백초, 울릉미역취 등이었다. 이들 추출물은 50%이상 colony수 감소율을 나타냈으며, 그 중 삼백초 추출물이 $E.$ $faecalis$에 항균활성 효과가 80%로 가장 높았다. Gram negative인 $Citrobacter$ $freundii$에 항균 활성 효과가 있는 허브 추출물은 구절초, 울릉미역취, 배암차즈기, 감국, 로즈마리, 케모마일, 라벤더 등 7종이었다. 특히, 구절초와 케모마일은 $C.$ $freundii$에 항균활성 효과가 가장 높게 나타났는데, 구절초 추출물은 $10^2mg{\cdot}L^{-1}$에서 90.7%, $10^3mg{\cdot}L^{-1}$에서 99.45%의 colony수가 감소되었으며, 케모마일 추출물은 $10^2mg{\cdot}L^{-1}$에서 89.4%, $10^3mg{\cdot}L^{-1}$에서 99.1%의 colony수가 감소되는 결과를 얻었다. 또한 Gram negative인 $Escherichia$ $coli$에 항균활성 효과가 있는 허브 추출물은 백리향, 울릉미역취, 배암차즈기, 로즈마리, 라벤더 등 5종이었다.