• 한국미생물·생명공학회지
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• 제13권3호
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• pp.203-207
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• 1985

장내세균 Bifidobacterium longum에 의한 대장균성 설사증의 주 원인균인 E. coli $A_2$의 생육저해를 혐기적 조건에서 조사한 결과를 요약하면 다음과 같다. 한국 성인으로부터 분리ㆍ동정한 Bif. longum SKD-2001은 E. coli $A_2$의 생육을 저해시키는 생육저해 작용을 가지고 있었다. Bifidus 균제제에서 분리ㆍ동정한 Bif. longum SKD-2004도 역시 E. coli $A_2$의 생육을 저해하였다. pH가 저하됨에 따라서 생육저해가 있는 것으로 보아 E. coli $A_2$의 생육저해는 Bif., longum이 생산한 lactic acid와 acetic acid에 의해 배양액의 pH가 저하됨으로써 나타나는 것으로 사료되었다.

• 미생물학회지
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• 제11권4호
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• pp.175-180
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• 1973

This study was attempted to see more clear relationships among the enterobacteria, especially between the intestinal normal flora and pathogenic bacteria. It has been known that some intestinal normal flora produce the bactrial metabolites that are harmful to other enteric bacteria. One of the metabolites is known as colicin, the protein fraction, which possesses certain degree of inhibitory effect against other bacterial growth fraction, whih possesses certain degree of inhibitory effect against other bacterial growth. As a preliminary study for a colicin purification, the antagonistic effect of E, coli to groups of Salmonella and Shigella has been studied by means of in vitro quantitative culture method. 1. E.coli showed definite inhibitory effects aganist both Salmonella and Shigella groups in the mixture of two organisms. 2. The inhibitory effects of E.coli in the E.coli-Salmonella and the E.coli-Shigella mixture occurred from 4 hours incubation following the inoculation. 3. Even the complete inhibition of pathogenic enteric bacterial growth was noticed in the E.coli-Salmonella mixture at overnight incubation. 4. Among the diluted mixtures, 1:100, 1:1,000, and 1:10,000, survival rate of pathogenic enteric bacteria in the mixtures with E.coli showed least affected at the 1:1,000 dilution. 5. It was found that the antagonistic effect aganist groups of Salmonella-shigella was depending upon the groups of the genera.

• 한국축산식품학회지
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• 제22권1호
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• pp.66-71
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• 2002

예천산 프로폴리스는 ethanol과 butanol 분획물이 S.typhimurium과 B. subtilis에 강한 항미생물 활성을 보였으며, 용매별로는 butanol, ethyl acetate, chloroform 분획물의 순이었다. C. utilis와 A. niger에는 모든 분획물이 항균활성을 나타내지 않았다. 농도별 균생육 억제 시험 결과, E. coli의 경우 예천산은 0.4mg/ml에서 초기에 균증식이 억제되었으며 영월은 0.25mg/ml에서 12시간 이후 균증식이 완전히 억제되었다. S. aureus의 경우, 영월과 예천산 프로폴리스가 0.25와 0.30mg/ml에서 완전히 균증식을 억제시켰다. P. aeruginosa의 경우, 예천산 프로폴리스는 0.20mg/ml에서 12시간 이후 균생장 억제를 보였으며, 영월산 프로폴리스는 0.20mg/ml에서 균생장이 완전히 억제되었다. S. typhimurium의 경우, 영월산은 0.20, 0.25mg/ml에서 균증식이 거의 억제되었으며, 예천산은 0.40mg/ml에서 균증식이 거의 억제되었다. MIC는 예천산 프로폴리스가 P. aeruginosa가 >0.2mg/ml로 가장 낮았고 S. aureus 0.25mg/ml, S. typhimurium > 0.35mg/ml 순이었다. 영월산은 P. aeruginosa가 0.15mg/ml로 가장 낮았으며 E. coli, S. aureus 및 S. typhimurium이 0.25mg/ml, B. subtilis 와 C. utilis는 각각 0.3, 0.4mg/ml 이었다.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2460-2464
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• 2014

Recently studies indicate that the microcalorimetry is a suitable measurement for metabolic activities of organisms by recording the rate of heat outputs. In this work, we investigated the growth thermogenic curves of Escherichia coli (E. coli) affected by three kinds of Glycyrrhiza extracts by microcalorimetry. The power-time and exponential phase power-time curves of the E. coli growth at various concentrations of extracts were generated. The kinetic parameters such as the growth rate constants (C), maximum power outputs (Pm), peak times (Tm), and inhibition ratios were calculated and the relationships between Pm or Tm and C were established. Also, the clear correlations among the antimicrobial effects, Pm and C were obtained. The results revealed the Glycyrrhiza extracts had inhibitory activities towards E. coli while the Glycyrrhiza polysaccharides showed the most potent effects.

• 한국식품과학회지
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• 제18권4호
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• pp.249-254
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• 1986

Escherichia coli와 Salmonella typhimurium의 생육을 억제하기 위하여 TGY, TSB (pH 6)의 액체배지에 potassium sorbate와 sodium benzoate를 각각 최고 허용농도의 1/2량인 0.1%, 0.03%로 처리하고 식염을 내염성 기준 농도인 2%로 첨가하여 보존료의 단독 및 병용효과와 식염과의 상승효과를 진탕 및 정치배양 조건에서 조사하였다. E. coli는 진탕배양보다 정치배양하였을 때 보존료의 단독 혹은 병용효과가 더 컸으며 S. typhimurium은 보존료를 단독처리하였을 때에는 억재효과를 보이지 않았으나 병용처리의 경우에 진탕배양에서는 정균효과를 현저하게 나타내었고 정치배양에서는 유도기를 연장시켰다. 식염의 첨가는 E. coli의 경우, 진탕배양에서는 거의 효과를 나타내지 않았으나 정치배양시에는 potassium sorbate 단독처리구 및 potassium sorbate + sodium benzoate병용처리구에서 항균작용을 현저히 증가시켰다. 식염의 상승효과는 S. typhimurium의 경우에 더욱 현저하였는데 진탕 및 정치배양시에 두 보존료와 식염의 혼합구에서 배양 중의 세균수는 오히려 초기농도보다 점점 감소되는 결과를 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제18권7호
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• pp.1278-1285
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• 2008

The intestinal epithelial cell (IEC) layer of the intestinal tract makes direct contact with a number of microbiota communities, including bacteria known to have deleterious health effects. IECs possess innate protective strategies against pathogenic challenge, which primarily involve the formation of a physicochemical barrier. Intestinal tract mucins are principal components of the mucus layer on epithelial surfaces, and perform a protective function against microbial damage. However, little is currently known regarding the interactions between probiotics/pathogens and epithelial cell mucins. The principal objective of this study was to determine the effects of Lactobacillus on the upregulation of MUC2 mucin and the subsequent inhibition of E. coli O157:H7 attachment to epithelial cells. In the current study, the attachment of E. coli O157:H7 to HT-29 intestinal epithelial cells was inhibited significantly by L. acidophilus A4 and its cell extracts. It is also important to note that the expression of MUC2 mucin was increased as the result of the addition of L. acidophilus A4 cell extracts (10.0 mg/ml), which also induced a significant reduction in the degree to which E. coli O157:H7 attached to epithelial cells. In addition, the mRNA levels of IL-8, IL-1$\beta$, and TNF-$\alpha$ in HT-29 cells were significantly induced by treatment with L. acidophilus A4 extracts. These results indicate that MUC2 mucin and cytokines are important regulatory factors in the immune systems of the gut, and that selected lactobacilli may be able to induce the upregulation of MUC2 mucin and specific cytokines, thereby inhibiting the attachment of E. coli O157:H7.

• 대한수의학회지
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• 제52권1호
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• pp.33-38
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• 2012

Germanium biotite, a natural mineral, has been used as a feed supplement to reinforce innate immune ability. The aim of the present study was to evaluate the effects of germanium biotite on the adsorptive and inhibition of growth abilities against Escherichia (E.) coli and Salmonella spp. in vitro. Two strains of enterotoxigenic E. coli and four strains of two Salmonella serotypes (Salmonella Derby and Salmonella Typhimurium), major bacterial diarrheal pathogens, were used for this experiment. The absorptive ability of germanium biotite against most Salmonella used in present experiment was observed weakly. The germanium biotite, however, showed significant effect of bacterial growth inhibition in most experiment bacteria. These results suggest that the use of the germanium biotite as feed supplement could alleviate diarrhea following inhibition of bacteria growth. It is also presumed that antibiotics usage for farm animals, considered as causes of antibiotic residue in meat and emerging antibiotic resistance, could be reduced through the use of germanium biotite as a feed supplement, in place of antibiotics used for the prevention of diarrhea.

• Restorative Dentistry and Endodontics
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• 제17권1호
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• pp.134-140
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• 1992

The purpose of this study was to investigate the antibacterial effect of zinc oxide eugenol(ZOE), zinc phosphate cement(ZPC), glass ionomer cement, resin, and Vitapex to S. muntans, S. sanguis, S. fecalis and E. coli by agar diffusion method. Four wells were punctured in mitis-salivarius agar plate per each group and each wells were filled with restorative matetials. The width of inhibition zones produced in mitis - salivarius agar were measured as the parameter of the antibacterial effect after 16 hours and 40 hours. In S. mutans and S. sanguis, the largest inhibition zone was produced on ZOE, followed by glass ionomer cement, and ZPC. Inhibition zones was not observed in resin and Vitapex. In S. fecalis, ZOE and glass ionomer cement showed wider inhibition zone than ZPC. In E. coli, ZOE showed wider inhibition zone than ZPC, but no inhibition zone was observed on glass ionomer cement.

• KSBB Journal
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• 제9권5호
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• pp.492-498
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• 1994

설관막 장치를 이용하여 대장균의 투석배양을 수 행했다. 투석액으로 배지 내의 초산을 제거함으로써 초산의 저해효과를 경감할 수 있었다. 초산 생성속도는 포도당과 용존산소농도에 대단히 민감하였고, 따라서 막을 통한 포도당의 투과속도는 산소공급속도와 균형을 유지해야 했다. 막을 통해 포도당이 천 천히 공급될 때, 대장균의 비성장속도는 포도당 투 과속도에 좌우되었고 초산의 생성은 억제되였다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1996년도 추계 학술발표회
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• pp.500-506
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• 1996

To study antimicrobial activities of Impatiens balsamina, its leaf and stem was extracted by methanol and water. The extracts were tested their microbial inhibition activities against several microorganisms, staphylococcus aureus KCTC 1928, Escherichia coli KCTC 1116, Klebsiella pneumoniae KCTC 2690, Trichophyton mentagrophytes KCTC 6316. The methanol extract and water extract of the leaf and stem didn't show the inhibition effect on E. coli but showed the inhibition effect against the ohter 3 species of the microorganisms tested. The extract of leaf showed higher inhibition than the extract of stem. And the methanol extract showed higher inhibition than the water extract.