• Title/Summary/Keyword: pathogens bacteria

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Growth Inhibition of E. coli O157:H7 and Salmonella typhimurium by Lactic Acid Bacteria and Bifidobacteria (젖산균과 비피더스균에 의한 Escherichia coli O157:H7과 Salmonella typhimurium의 생장억제)

  • 김현욱;안영태;신필기
    • Journal of Food Hygiene and Safety
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    • v.12 no.3
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    • pp.181-187
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    • 1997
  • Lactobacillus acidophilus NCFM, Lactobacillus casei YIT 9018, Bifidobacterium longum 8001, and Bifidobacterium longum 8025 at the level of 106 cfu/$m\ell$ were cultured with 104 cfu/$m\ell$ of Escherichia coli O157:H7 KSC 109 or Salmonella typhimurium ATCC14028, in order to verify the effects of lactic acid bacteria and bifidobacteria on the growth of the pathogens. In the mixed culture of lactic acid bacteria with E. coli O157:H7 KSC 109, Growth inhibition and atypical microcolonies of E. coli O157:H7 KSC 109 were observed. The pathogens inoculated grew for 5 hors (pH 5.3), by the time L. acidophilus NCFM reached the exponential growth phase, and then the surviving pathogens were decreased to 101 cfu/$m\ell$ after 35 hours. When L. caseiYIT 9018 was grown with the pathogens, they grew for 10 hours (pH 4.6), by the time L. casei YIT 9018 reached the end of exponential growth phase, and then the surviving pathogens were decreased drastically. Up to the stationary growth phase of lactic acid bacteria, L. acidophilus NCFM exhibited stronger inhibition against the pathogens than L. casei YIT 9018 did, which might be attributed to its faster growth. Likewise bifidobacteria inhibited the growth of the pathogens tested, bifidobaceria was weaker in the inhibitory activity than lactic acid bacteria. When Bifidobacterium longum 8001 was cultured with the pathogens, E. coli O157:H7 KSC 109 was gradually ingibited at the stationary growth phase of bifidobacteria, atypical microcolonies were formed on Levine EMB medium after 48 hours, and Salmonella grew up to 106 dfu/$m\ell$, then was drastically ingibited at the exponential growth phage of Bifidobacterium longum 8001. But when Bifidobacteriuam longum 8025 was cultured with the pathogens, the pathogens grew to the same level of Bifidobacteriuam longum 8025 was cultured with the pathogens, the pathogens grew to the same lever of Bifidobacteriuam longum 8025 after 10 hours, then the surviving pathogens were decreased drastically.

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Effect of Kimchi ingredients on the growth of pathogenic and lactic acid bacteria (김치부재료의 유산균 증식 및 유해균 억제효과)

  • Kang, Sun-Yi;Han, Myung-Joo
    • Korean journal of food and cookery science
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    • v.21 no.6 s.90
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    • pp.838-843
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    • 2005
  • When ingredients of Kimchi were mixed and stored in $18^{\circ}C$, lactic acid bacteria, such as Leuconostoc mesenteroides and Lactobacillus plantarum, were selectively grown up. Herefore, to understand why lactic acid bacteria were selectively cultured in Kimchi, antibacterial activities of Kimchi ingredients against some pathogens and Kinlchi lactic acid bacteria were investigated. Kimchi mixed with all ingredients significantly inhibited the growth of all tested pathogens: S. typhimurium, S. sonnei, and E. coli. Kimchi without green onion, garlic or ginger inhibited the growth of S. typhimurium, but did not E. coli and S. sonnei. However, Kimchi without red pepper powder did not inhibit the growth of all tested pathogens. All ingredients of Kimchi did not inhibit the growth of L. plantarum and L. mesenteroides. These results suggest that Kimchi ingredients can synergistically inhibit the growth of pathogens and Kimchi may be a selective medium for lactic acid bacteria.

Aerobic bacteria from oral cavities and cloaca of snakes in a petting zoo

  • Jho, Yeon-Sook;Park, Dae-Hun;Lee, Jong-Hwa;Lyoo, Young S.
    • Korean Journal of Veterinary Research
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    • v.51 no.3
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    • pp.243-247
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    • 2011
  • It is important to identify the bacteria in snakes because they can cause disease; importantly, bacteria such as Stenotrophomonas maltophilia, Escherichia coli, Proteus vulgaris etc. could be pathogens especially in hospitalized, debilitated hosts, and immunocompromised patients. To analyze the distribution of snakes' bacteria in petting zoo, samples from 20 snakes were collected from 2002 to 2008. Nine bacteria species were isolated from both oral and cloaca while four and six species were identified only from oral and cloaca, respectively. Except for Actinobacter sp., all of the identified strains are opportunistic pathogens, and most of them can cause nosocomial infections in humans. Present results indicate that prevalence of various zoonotic bacterial strains in snakes could be involved in potential transfer of these bacteria into caretakers and other animals. Therefore, it needs to examine the antibiotic resistance of these pathogens to prevent outbreaks.

Quantitative Analysis of Oral Pathogenic Bacteria according to Smoking Using Real-Time PCR

  • Jeon, Eun-Suk;Heo, Hyo-Jin;Ko, Hyo-Jin
    • Journal of dental hygiene science
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    • v.18 no.1
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    • pp.60-68
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    • 2018
  • This study investigates the relationship between smoking and periodontal disease through quantitative analysis of intra-buccal oral pathogenic bacteria detected in smokers and aims to yield objective baseline data for applications in anti-smoking and dental health education programs. From April to May 2016, participants in an oral health management program within an intensive dental hygiene training course at Choonhae College of Health Sciences received an explanation of the study purposes and methods, after which male smokers aged 18~30 years agreed to participate voluntarily. Real-time polymerase chain reaction (PCR) analysis of oral pathogenic bacteria was performed after collecting gingival sulcus fluid samples from 67 smokers. The intra-buccal oral pathogenic bacteria distributions were analyzed based on the subjects' general characteristics, smoking behaviors, and oral care behaviors. The distribution results show that pathogens in the anterior teeth are affected (in this order) by age, toothbrush size, and smoking status; older people had fewer pathogens, those who used larger toothbrushes had more pathogens, and smokers had more pathogens, compared to non-smokers ($_{adj}R^2=19.1$). In the posterior teeth, pathogens were influenced (in this order) by smoking status, smoking duration, and the number of tooth brushings per day; smokers had more pathogens than non-smokers, and those who brushed their teeth more often had fewer pathogens ($_{adj}R^2=25.1$). The overall pathogen distribution was affected only by smoking status: smokers generally had more pathogens, compared to non-smokers. Therefore, it is necessary to provide information about the risk of periodontal disease due to smoking during anti-smoking or dental health education sessions; particularly, the use of smaller toothbrushes for anterior teeth and the need for smokers in their early twenties to quit smoking for dental health should be highly emphasized.

Inactivation of Foodborne Pathogens by Lactic Acid Bacteria

  • Daliri, Frank;Aboagye, Agnes Achiaa;Daliri, Eric Banan-Mwine
    • Journal of Food Hygiene and Safety
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    • v.35 no.5
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    • pp.419-429
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    • 2020
  • The problems caused by foodborne pathogens are not only a concern to the food industry but also with regard to global public health. Over the years, fermentation technology has proved to be one of the cheapest and safest methods for inactivating and controlling pathogenic microorganisms in food. Scientific evidence shows that lactic acid bacteria fermentation exerts significant antimicrobial effect against pathogenic bacteria and viruses. Lactic acid bacteria metabolites such as organic acids, bacteriocins and hydrogen peroxides have adverse effects on foodborne pathogens which lead to their inhibition. These compounds do not only cause physical injuries, but also have significant effects on the pathogens' gene expression. Furthermore, the presence of lactic acid bacteria in food provides nutritional competition among foodborne pathogens, and all these factors together suppress their growth. This study reviews our current knowledge of the antimicrobial abilities of lactic acid bacteria, their molecular mechanisms, and their application for inactivating foodborne pathogens.

Screening for In Vitro Antifungal Activity of Soil Bacteria Against Plant Pathogens

  • Chang, Sung-Hwan;Lee, Jung-Yeop;Kim, Ki-Deok;Hwang, Byung-Kook
    • Mycobiology
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    • v.28 no.4
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    • pp.190-192
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    • 2000
  • Antifungal bacteria for biological control of plant diseases or production of novel antibiotics to plant pathogens were isolated in 1997 from various soils of Ansung, Chunan, Koyang, and Paju in Korea. Sixty-four bacterial strains pre-screened from approximately 1,400 strains were tested on V-8 juice agar against eight plant pathogenic fungi using in vitro bioassay technique for inhibition of mycelial growth. Test pathogens were Alternaria mali, Colletotrichum gloeosporioides, C. orbiculare, Fusarium oxysporum f. sp. cucumerinum, F. oxysporum f. sp. lycopersici, Magnaporthe grisea, Phytophthora capsici, and Rhizoctonia solani. A wide range of antifungal activity of bacterial strains was found against the pathogenic fungi, and strain RC-B77 showed the best antifungal activity. Correlation analysis between inhibition of each fungus and mean inhibition of all eight fungi by 64 bacterial strains revealed that C. gloeosporioides would be best appropriate for detecting bacterial strains producing antibiotics with potential as biocontrol agents for plant pathogens.

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Weissella confusa Strain PL9001 Inhibits Growth and Adherence of Genitourinary Pathogens

  • Lee, Yeon-Hee
    • Journal of Microbiology and Biotechnology
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    • v.14 no.4
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    • pp.680-685
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    • 2004
  • The capability of lactic acid bacteria (LABs) to adhere to intestinal epithelial cells and vaginal epithelial cells is an important factor in the formation of a barrier to prevent the colonization of pathogenic bacteria. In addition, the ability to coaggregate with pathogens and production of antimicrobial agents also allow LABs to fight against pathogens. In this work, Weissella confusa PL9001 was tested for its ability to inhibit the growth and adherence of genitourinary pathogens, including Candida albicans, Escherichia coli, Staphylococcus aureus, and vancomycin-resistant Enterococcus faecium (VRE), isolated from the urine of hospitalized female patients. W. confusa PL9001 was found to coaggregate with the four pathogens, as observed with a light microscope and scanning electron microscope. In competition, exclusion, and displacement tests, the adherence of the pathogens to T24 bladder epithelial cells was also inhibited by W. confusa PL9001. Accordingly, these results suggest that W. confusa PL9001 is potentially useful for both preventive and therapeutic treatment of genitourinary infections.

Public Health Risks: Antibiotic Resistance - Review -

  • Barton, Mary D;Hart, Wendy S
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.3
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    • pp.414-422
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    • 2001
  • Antibiotic resistance in human pathogens is a major public health issue. Some of the resistance problem can be attributed to the transfer of resistant bacteria from animals to people and the transfer of resistance genes from animal pathogens and commensal bacteria to human pathogens. Control measures include improvements in food hygiene to reduce the spread of zoonotic bacteria to people via the food chain. However, to specifically address the issue, the medical profession must control misuse and overuse of antibiotics in hospitals and community practice. In addition, the livestock industries and their advisors must reduce and refine the use of antibiotics in animal production and replace antibiotics with alternative disease control measures as much as possible.

Innate immune response to oral bacteria and the immune evasive characteristics of periodontal pathogens

  • Ji, Suk;Choi, Youngnim
    • Journal of Periodontal and Implant Science
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    • v.43 no.1
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    • pp.3-11
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    • 2013
  • Periodontitis is a chronic inflammation of periodontal tissue caused by subgingival plaque-associated bacteria. Periodontitis has long been understood to be the result of an excessive host response to plaque bacteria. In addition, periodontal pathogens have been regarded as the causative agents that induce a hyperinflammatory response from the host. In this brief review, host-microbe interaction of nonperiodontopathic versus periodontopathic bacteria with innate immune components encountered in the gingival sulcus will be described. In particular, we will describe the susceptibility of these microbes to antimicrobial peptides (AMPs) and phagocytosis by neutrophils, the induction of tissue-destructive mediators from neutrophils, the induction of AMPs and interleukin (IL)-8 from gingival epithelial cells, and the pattern recognition receptors that mediate the regulation of AMPs and IL-8 in gingival epithelial cells. This review indicates that true periodontal pathogens are poor activators/suppressors of a host immune response, and they evade host defense mechanisms.

Investigation of Microbial Safety and Correlations Between the Level of Sanitary Indicator Bacteria and the Detection Ratio of Pathogens in Agricultural Water (농업용수의 미생물학적 안전성 조사 및 위생지표세균 농도와 병원성미생물 검출률과의 상관관계 분석)

  • Hwang, Injun;Lee, Tae Kwon;Park, Daesoo;Kim, Eunsun;Choi, Song-Yi;Hyun, Jeong-Eun;Rajalingam, Nagendran;Kim, Se-Ri;Cho, Min
    • Korean Journal of Environmental Agriculture
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    • v.40 no.4
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    • pp.248-259
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    • 2021
  • BACKGROUND: Contaminated water was a major source of food-borne pathogens in various recent fresh produce-related outbreaks. This study was conducted to investigate the microbial contamination level and correlations between the level of sanitary indicator bacteria and the detection ratio of pathogens in agricultural water by logistic regression analysis. METHODS AND RESULTS: Agricultural water was collected from 457 sites including surface water (n=300 sites) and groundwater (n=157 sites) in South Korea from 2018 to 2020. Sanitary indicator bacteria (total coliform, fecal coliform, and Escherichia coli) and food-borne pathogens (pathogenic E. coli, E. coli O157:H7, Salmonella spp., and Listeria monocytogenes) were analyzed. In surface water, the coliform, fecal coliform, and E. coli were 3.27±0.89 log CFU/100 mL, 1.90±1.19 log CFU/100 mL, and 1.39±1.26 log CFU/100 mL, respectively. For groundwater, three kinds of sanitary indicators ranged in the level from 0.09 - 0.57 log CFU/100 mL. Pathogenic E. coli, Salmonella and Listeria monocytogenes were detected from 3%-site, 1.5%- site, and 0.6%-site water samples, respectively. According to the results of correlations between the level of sanitary indicator bacteria and the detection ratio of pathogens by logistic regression analysis, the probability of pathogen detection increased individually by 1.45 and 1.34 times as each total coliform and E. coli concentration increased by 1 log CFU/100mL. The accuracy of the model was 70.4%, and sensitivity and specificity were 81.5% and 51.7%, respectively. CONCLUSION(S): The results indicate the need to manage the microbial risk of agricultural water to enhance the safety of fresh produce. In addition, logistic regression analysis is useful to analyze the correlation between the level of sanitary indicator bacteria and the detection ratio of pathogens in agricultural water.