• 한국동물위생학회지
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• 제15권2호
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• pp.134-143
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• 1992

The present study was conducted to investigate the biochemical characteristics and anti-biotic resistance of Escherichia coli(E. coli) isolated from piglets with diarrhea in Kyongbuk province during the Period from February to November 1991. 368 E. coli strains were isolated from 382 piglets with diarrhea and the biochemical and cultural reaction were compared with the classification criteria of Edwards and Ewing. Tetracycline and sulfadimethoxine were found to be highly ineffective at in vitro inhibition of the E. coli of piglets origin. The majority of E. coli were susceptible to amikacin, chloramphenicol and gentamicine. 89 (89.0%) of 100 strains of E. coil were resistant to one or more drugs. The organisms resistant to 20 or 3 drugs were 54(60.6%) of 89 strains, whereas 16(17.9%) strains were found to be resistant to one drug. 55(61.8%) out of 89 drug resistance strains carried R factors($R^+$) which were transfer-able to the recipients by conjugation.

• 한국식품위생안전성학회지
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• 제12권3호
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• pp.188-194
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• 1997

The growth inhibition effect of Orally administrated yogurt ACE and Metchnikoffupon E. coli O157:H7 and S. typhimurium inoculated into gastric lumen of rabbits was in vestigated. The rabbits challenged with each 1 $m\ell$ of suspension containing 108 CFU/$m\ell$ of the pathogens were divided into 4 groups by the interval of yogurt administration: A group; preadministrated 7 days before inoculation of the pathogens and fed daily; B group; administrated daily after inocjlation of the pathogens, C group; administrated every 3 days after inoculation of the pathogens; Control group, not fed after inoculation of the pathogens. Each 3 $m\ell$ of yogurt containing 109 CFU/$m\ell$ was orally administrated into rabbits. All yogurt administrated groups (A, B, c) chowed growth ingibition effect on E. coli O157:H7 in one day after inoculation of the pathogen by the level of 0.8~1.0 log CFU/g, compared with the result differences between the control group and the yogurt administrated groups. In the control group after 5 days of inoculation, the number of colonized pathogens was 105~106 CFU/g, whereas 103~104 CFU/g was detected in the yogurt administrated groups. After 10 days of inoculation, the viable pathogen number per gram (g) of the rabbit feces was 103 CFU/g in the control group, whereas the number below 101 CFU/g was detected in the group A, and 102 CFU/g in the control group, B and C. The growth inhibition effect of yogurt administration on E. coli O157:H7 was highly increased in the order of A, B, and C group. The same effect on S. typhimurium was observed at the level of 2 log CFU/g in the Metchnikoff yogurt administrated groups, compared with the control group result in one day after inoculation of the pathogen. In 7 days after inoculation of the pathogen, the viable number was increasingly decreased, and finally after 15 days no viable cell of S. typhimurium was discharged into the fecal samples in the group A, and the mean level of 10* CFU/g was detected in the group B, but there was no growth inhibition effect in the group C. The growth inhibition effect on S. typhimurium was observed at the same level of viable cell number between the yogurt ACE administrated groups and the control group in 5 days after inoculation. But, after 10 days of inoclation the viable cell number was started to decrease, and the viable cell of S. typhimurium was not discharged from rabbit intestinal contents after 15 days of inoculation in the yogurt ACE administrated groups. In such a case that yogurt was administrated in order to prevent the pathogens, pre-administration on a daily basis one week before inoculation of the pathogens exerted considerable effect in growth inhibition. In comparison with two kinds of yogurt tested in this study, the growth inhibition effect on two kinds of pathogens was observed more highly in the Metchnikoff administated group than the ACE administrated group.

• Journal of Animal Science and Technology
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• 제44권4호
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• pp.491-498
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• 2002

본 실험에서는 lactobacilli와 bifidobacteria에 의한 E. coli와 S. typhimurium에 대한 생육 억제능을 조사 하였다. 생육억제활성은 well disc assay와 turbidimetry method로 측정하여 비교하였다. 시험균주 10종 중에서 두 가지 방법 모두 평균적으로 높은 항균 활성을 나타낸 균주는 L. acidophilus La-5, L. acidophilus NCFM와 L. casei Lc-01인 것으로 나타났다. 선택된 3가지 유산균과 대표적 enteropathogen인 E. coli와 S. typhimurium을 각각의 혼합 배양하여 생균수를 측정한 결과 병원성균 생육억제는 생균수가 급격히 감소하는 배양 9시간 이후부터 나타났으며 30시간 혼합배양 후에는 병원성균의 생균수는 거의 존재하지 않았다. 실험결과 유산균의 항균활성은 pH 저하 만에 의한 것이 아니었고 유산균의 종류에 따라 생육억제활성에 차이가 있었다.

• 한국축산식품학회지
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• 제36권2호
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• pp.186-193
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• 2016

This study aimed to inhibit Escherichia coli (E. coli) O157:H7 artificially contaminated in fresh meat using bacteriophage. Among 14 bacteriophages, the highly lytic bacteriophage BPECO19 strain was selected to inhibit E. coli O157:H7 in artificially contaminated meat samples. Bacteriophage BPECO19 significantly reduced E. coli O157:H7 bacterial load in vitro in a multiplicity of infection (MOI)-dependent manner. E. coli O157:H7 was completely inhibited only in 10 min in vitro by the treatment of 10,000 MOI BPECO19. The treatment of BPECO19 at 100,000 MOI completely reduced 5 Log CFU/cm² E. coli O157:H7 bacterial load in beef and pork at 4 and 8h, respectively. In chicken meat, a 4.65 log reduction of E. coli O157:H7 was observed at 4 h by 100,000 MOI. The treatment of single bacteriophage BPECO19 was an effective method to control E. coli O157:H7 in meat samples.

• 대한의생명과학회지
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• 제13권1호
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• pp.47-53
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• 2007

Due to wide abuse of antibiotics both in human and livestock use, the advent and spread of multidrug resistant (MDR) pathogens becomes a serious health problem all over the world. Since the development of new antibiotics is at a standstill in pharmaceutical industry, the choice of therapeutic antibiotics is getting narrower. In this study, in an effort to search new antibiotics, the antimicrobial activity of Paenibacillus DY1 isolated from Korean soil was characterized on its growth inhibition spectrum against various health threatening MDR strains, with its stability and chemical structure. Extracellular culture filtrate of Paenibacillus DY1 effectively inhibits the growth of all the tested MDR enteropathogenic Eshcherichia coli, enterohemolytic E. coli, and enterotoxigenic E. coli strains, at a similar level to that on the nonresistant control E. coli strains. It showed significant growth inhibition effect against the causative agents of class one legal communicable disease, MDR Salmonella typhi, MDR Salmonella paratyphi A, food poisoning bacteria, MDR Salmonella typhimurium, and other MDR Salmonella spp. The growth of all of 10 different MDR Shigella spp. strains and 6 different Vibrio spp. strains tested was also inhibited. The antimicrobial activity of Paenibacillus DY1 was well preserved after heat treatment, and was also stable in both alkaline and acidic environment. The antimicrobial activity was partially purified with Diaion HP20 column and TLC. By NMR study, the putative structure of the activity was postulated as an alkane having hydroxyl groups.

• Food Science and Biotechnology
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• 제15권5호
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• pp.817-819
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• 2006

8-Quinolinol and other quinolinol derivatives were evaluated with regard to their growth-inhibitory effects against intestinal bacteria, using the paper disk-agar diffusion method. The observed growth responses varied according to the chemicals and dosages used, as well as the bacterial species tested. 8-Quinolinol showed a significant inhibitory effect against Clostridium difficile, C. perfringens, and Escherichia coli, at 5, 2, 1, and 0.5 mg/disk, and also exhibited a very strong inhibitory effect at 0.25 mg/disk. At low concentrations, 8-quinolinol had strong inhibitory effects against C. perfringens at 0.1 and 0.05 mg/disk; 8-quinolinol also manifested a moderate inhibitory effect against C. perfringens at 0.025 mg/disk. Furthermore, 8-quinolinol revealed moderate and weak growth inhibition against C. difficile and E. coli at concentrations of 0.1 and 0.05 mg/disk, respectively, but 2-quinolinol, 4-quinolinol, and 6-quinolinol evidenced no growth inhibition against B. bifidum, B. longum, C. difficile, C. perfringens, E. coli, or L. casei. The inhibitory effects of 8-quinolinol against C. difficile, C. perfringens, and E. coli lead to its consideration as a possible therapeutic modality for the treatment of diseases associated with harmful intestinal bacteria.

• Food Science and Biotechnology
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• 제15권4호
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• pp.559-563
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• 2006

The growth responses of six bacterial strains exposed to materials extracted from turmeric (Curcuma longa) rhizomes were examined using impregnated paper disk agar diffusion. Methanol extracts of turmeric rhizomes exhibited strong inhibitory activity against Clostridium perfringens and weak inhibitory activity toward Escherichia coli at 5 mg/disk. However, in tests conducted with Bifidobacterium adolescentis, B. bifidum, B. longum, and Lactobacillus casei, the methanol extract showed no inhibitory response. The biologically active constituent isolated from the turmeric rhizomes extracts was characterized as ar-turmerone using various spectroscopic analyses including EI-MS and NMR. The responses varied according to the dosage, chemicals, and bacterial strain tested. At 2 and 1 mg/disk, ar-turmerone strongly inhibited the growth of C. perfringens and moderately inhibited the growth of E. coli without any adverse effects on the growth of four lactic acid-bacteria. Of the commercially available compounds originating from turmeric rhizomes, curcumin exhibited strong and moderate growth inhibition against C. perfringens at 2 and 1 mg/disk, respectively, and weak growth inhibition against E. coli at 1 mg/disk. However, little or no activity was observed for borneol, 1,8-cineole, and sabinene against all six bacteria strains tested. The observed inhibitory activity of the turmeric rhizome-derived curcumin and ar-turmerone against C. perfringens and E. coli demonstrate one of the important pharmacological activities of turmeric rhizomes.

• Food Science and Biotechnology
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• 제14권1호
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• pp.164-167
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• 2005

The growth responses of materials extracted from Juniperus virginiana leaves against Bifidobacterium bifidum, B. longum, Clostridium perfringens, Escherichia coli, Lactobacillus acidophilus, L. casei, and Streptococcus mutans were examined using impregnated paper disk agar diffusion. The biologically active constituent isolated from the J. virginiana extracts was characterized as ${\alpha}$-cedrene using various spectroscopic analyses including IR, EI-MS, and NMR. The responses varied according to the dose, chemicals, and bacterial strain tested. Methanol extracts of J. virginiana leaves exhibited a strong and moderate inhibitory activity against C. perfringens and E. coli at 5 mg/disk, respectively. However, in tests conducted with B. bifidum, B. longum, L. acidophilus, L. casei, and S. mutans, the methanol extracts showed no or weak inhibitory response. At 2 mg/disk, a-cedrene strongly inhibited the growth of C. perfringens and moderately inhibited the growth of E. coli and S. mutans, without any adverse effects on the growth of four lactic acid-bacteria. Of the commercially available compounds originating from J. virginiana leaves, cedrol and ${\alpha}$-pinene exhibited strong and moderate growth inhibition against C. perfringens, and ${\alpha}$-copaene revealed moderate growth inhibition against E. coli at 1 mg/disk. Furthermore, cedrol exhibited moderate and weak growth inhibition against S. mutans at 2 and 1 mg/disk, respectively. However, little or no activity was observed for camphene, (+)-2-carene, p-cymene, limonene, linalool, and a-phellandrene against B. bifidum, B. longum, C. perfringens, L. acidophilus, L. casei, and S. mutans at 2 mg/disk. The observed inhibitory activity of the J. virginiana leaf-extracted materials against C. perfringens, E. coli, and S. mutans may be an indication of at least one of the pharmacological actions of the J. virginiana leaf.

• 한국식품조리과학회지
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• 제28권1호
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• pp.9-15
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• 2012

This study analyzed the antibacterial activity of a Rubus coreanum (Bokbunja) ethanol extract. The antimicrobial activity was determined by disc diffusion, minimum inhibitory concentration (MIC), and growth inhibition methods with seven kinds of bacteria related to foodborne illness (Bacillus cereus, Escherichia coli, Escherichia coli O157:H7, Listeria monocytogenes, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhimurium). In the results, disc diffusions of the ethanol extract from R. coreanum (9.8-17.5 mm at $4,000{\mu}g/disc$) clearly showed the antimicrobial activity of the extract against all tested microorganisms. Rubus coreanum promoted an inhibitory effect as follows: E. coli O157:H7 > P. aeruginosa > L. monocytogenes > E. coli > S. aureus > B. cereus ${\geq}$ S. typhimurium. In the MIC test, R. coreanum showed high antimicrobial effect against L. monocytogenes at 500 ppm. Moreover, the R. coreanum ethanol extract showed strong growth inhibition against microorganisms, similar to the MIC results. These results show that a R. coreanum ethanol extract has powerful antimicrobial activity against all tested microorganisms, suggesting that R. coreanum will be useful as a potential natural preservative.

• 한국응용과학기술학회지
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• 제37권1호
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• pp.145-152
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• 2020

본 연구에서는 붉나무 열매 Ethanol extract(ET)과 Ethyl acetate fraction(EA) 및 Butanol fraction(BT)을 천연보존제로서의 활용 가능성을 평가하기 위하여 항균활성을 측정 하였다. 항균활성은 Staphylococcus aureus(S. aureus), Staphylococcus epidermidis(S. epidermidis), Escherichia coli(E. coli), Pseudomonas aeruginosa(P. aeruginosa), Candida Albicans(Candida. A)에 대하여 Paper disc법으로 생육저해환과 최소저해농도(MIC)를 평가하였다. Paper disc법으로 생육저해환을 측정한 결과 ET, EA, BT 모든 시료에서 S. aureus, S. epidermidis, E. coli, P. aeruginosa 균주에서 생육저해환이 관찰되었고 BT에서는 Candida. A 균주에 대한 생육저해환이 추가로 관찰 되었다. MIC 측정결과 EA 시료가 S. aureus, S. epidermidis, E. coli, P. aeruginosa 대하여 가장 낮은 농도를 보였다. 따라서 본 연구의 결과는 붉나무 열매 추출물이 다양한 항균스펙트럼을 가지고 있어 화장품에서 천연보존제로 활용 가능성이 높다고 사료 된다.