• Food Science and Preservation
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• v.9 no.1
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• pp.102-108
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• 2002

The purpose of this study was to investigate antibacterial activity of extracts of Cordyceps spp.(Paecilomyces japonica and Cordyceps militaris), mugwort and pine needle. Fruiting body and mycelium of Cordyceps spp., mugwort and pine needle were extracted with water and 70% ethanol. Antibacterial activities of each extracts against 3 kinds of Gram positive (Bacillus subtilis, Listeria monocytogenes and Staphylococcus aureus) and 3 kinds of Gram negative pathogenic bacteria(Escherichia coli O157 : H7, Shigella sonnei and Salmonella typhimurium) were tested. The yields of water and ethanol extracts of fruiting body (39∼58%) were 2.4 ∼4.4 times higher than mycellium(9∼24%) in Cordyceps sup., while those of mugwort and pine needle were less than 9%. Ethanol extract of P. japonica mycelium(JFE) had antibacterial to S. monocytogenes at 1% level and ethanol extract of C. militaris fruiting body (MFE) had antibacterial to S. aureus at 3% level. Ethanol extract of mugwort was antibacterial against L monocytogenes and S. aureus at 1% level. Water extracts of Cordyceps spp.(P. japonica and C. militaris) and mugwort had no antibacterial activity against tested bacterial strains. Water extract of pine needle had antibacterial activity against all bacterial strains except E. coli and ethanol extract had antibacterial activity against all tested bacterial strains at 1% level. Pine needle extracts had the most wide antibacterial spectrum against bacterial strains used for this experiment. Growth inhibiting activities of pine needle extracts were higher in ethanol extract than water extract for most of tested bacteria in tryptic soy broth.

• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.130-135
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• 2005

To investigate the antimicrobial effect of the Patrinia scabiosaefolia extracts against food-borne pathogens, we extracted the P. scabiosaefolia with methanol at room temperature and the fractionation of the methanol extracts was carried out by using petroleum ether, chloroform, ethyl acetate, and methanol, respectively. The antimicrobial activity of the P. scabiosaefolia extracts was determined by using a paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extracts of P. scabiosaefolia showed the highest antimicrobial activity against Escherichia coli and Shigella sonnei. Synergistic effect in inhibition was observed when P. scabiosaefolia extract was mixed Forsythiae fructus extract as compared to each extracts alone. Finally, the growth inhibition curves were determined by using ethyl acetate extracts of P. scabiosaefolia against Staphylococcus epidermidis and Shigella sonnei. The ethyl acetate extract of P. scabiosaefolia had strong antimicrobial activity against S. sonnei at the concentration of 4,000 ppm. At this concentration, the growth of S. Sonnei was retarded more than 72 hours and up to 48 hours for S. epidermidis. These results suggest that the ethyl acetate extracts of P. scabiosaefolia can be used for the efficient material against the growth of S. epidermidis and S. sonnei.

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.356-365
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• 2012

There have been growing concerns among people about food safety due to insufficient information on foodborne pathogens. In this study, we developed a risk priority of 15 foodborne pathogens. For the priority determination we collected risk profile criteria information from CODEX Alimentarius Commission and developed countries. The basis for criteria we selected from information of surveillance were frequency and severity of disease, frequency of consumption and probability of cross-contamination. We also considered foodborne pathogens which have been managed in developed countries though those pathogens are not currently managed appropriately in Korea. Priorities were divided into three groups following these consideration. The first priority group includes Norovirus, pathogenic E. coli, Salmonella spp, Clostridium botulinum and Listeria monocytogenes. The second priority group includes Vibrio parahaemolyticus, Stapylococcus aureus, Campylobacter jejuni and Bacillus cereus, and the third priority group includes Clostridium perfringens, Yersinia enterocolitica, Shigella spp, Cronobacter sakazakii and Hepatitis A virus. Our results could be applied to prevent foodborne illness from fresh produce.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.110-116
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• 2019

To investigate the antagonistic inhibitory effects in a mixed culture between probiotics and various pathogenic microorganisms, 140 probiotics were identified using a 16 rRNA sequencing phylogenetic analysis method, and various probiotics strains were isolated from Korean kimchi from January to December 2016. The antagonistic inhibition test of a mixed culture of four probiotics (Enterococcus faecalis, Lactobacillus plantarum, Lactobacillus rhamnosus, and Lactobacillus reuteri) with excellent antimicrobial activity and six pathogenic microorganisms (Candida albicans, Salmonella Enteritidis, E. coli O157:H7, Shigella flexneri, Staphylococcus aureus, and Pseudomonas aeruginosa)showed that the growth of most probiotics strains increased normally after culture, but growth was inhibited almost completely in most pathogenic microorganisms, except for S. Enteritidis. This antagonistic inhibitory effect in vitro was attributed to the low pH of the lactic acid and organic acid produced during fermentation. As a result, four probiotics strains isolated from Korean Kimchi are very likely to be developed as therapeutic agents for female yeast infections and colon and skin care. In the future, these therapeutic agents will help improve public health related to probiotics.

• Journal of Food Hygiene and Safety
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• v.18 no.4
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• pp.229-236
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• 2003

The five different foodborne pathogenic bacterial genera of Escherichi, Salmonella, Shigella, Vibrio and Listeria are important sources of foodpoison. However, the method was not developed to simultaneously differentiate these five bacteria at molecular level. The optimized concentrations of the four major PCR cocktail components of $MgCl_2$, dNTPs, primers and template DNA were determined when ERIC (enterobacterial repetitive intergenic consensus)-PCR reactions were carried out to differentiate the five differnet foodborne pathogenic bacteria. The optimized concentration of $MgCl_2$ was determined to be 2 mM in order to obtain a consistent fingerprinitng pattern. The similar fingerprinting pattern was obtained when ERIC primers and dNTPs were added up to the concentrations of 2 ${\mu}M$ and 200 ${\mu}M$, respectively. As for template DNA, the numbers of PCR fragments were not affected, but their intensities were increased as the concentrations of the DNA were increased.

• Journal of Life Science
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• v.25 no.12
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• pp.1399-1407
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• 2015

Klebsiella pneumoniae is found in the normal flora of the skin, mouth, respiratory tract, urinary tract, and intestines in human. However, the stain is opportunistic pathogen, which is the causative agent of community acquired pneumonia. Corn silk has been known to be effective for antimicrobial activity against pathogenic bacteria, including K. pneumoniae, Staphylococcus aureus, Bacillus subtilis, Shigella spp., Salmonella spp., Escherichia coli, Pseudomonas aeruginosa, et al. In this study we focused on the antimicrobial properties of con silk water extract of K. penumoniae. K. pneumoniae isolates K. pneumoniae ATCC 13883 and broad-spectrum β-lactamase (BSBL), exteded-spectrum β-lactamase (ESBL), carbapenemase-producers. Antimicrobial susceptibilities were determined by the disk diffusion method. Searches for bla genes were performed by PCR amplication and direct sequencing. MacConkey agar plate medium was prepared using the corn silk extracts (50% or 100%) instead of distilled water for antimicrobial activity test. The microbial growth inhibitory potential of K. pneumoniae was determined by using the MacConkey agar plate spreading method, and the plate was incubated 18 hr at 37℃. Genes encoding β-lactamases including SHV-1 (n=8), SHV-2a (n=8), SHV-5 (n=2), SHV-11 (n=2), SHV-12 (n=18), TEM-1 (n=10), CTX-M-3 (n=2), CTX-M-14 (n=2), CTX-M-15 (n=1), GES-5 (n=5), KPC-2 (n=6), KPC-3 (n=4), and NDM-1 (n=2) were detected. The corn silk extract showed significantly antimicrobial activity against K. pneumoniae ATCC 13883, but BSBLs, ESBLs, and carbapenemase producers were not. Therefore, corn silk extract is thought to be able to assist in the prevention and rapid recovery of infectious disease caused by K. pneumoniae.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.495-501
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• 1999

Lactobacillus acidophilus KY 2104 was isolated from 41 healthy korean ($2{\sim}35\;age$, 26 man, 15 woman) feces to use as a probiotic lactic acid bacteria for functional foods, fermented milk and pharmaceutical products. L. acidophilus KY 2104 survived in the presence of acid and bile, and inhibited pathogens. It survived almost 100% in pH 3.0 phosphate buffer for 2 hr, and more than $10^4\;cfu/mL$ in pH 2.0 phosphate buffer when inoculated by $10^7\;cfu/mL$. It was also found to grow in MRS medium containing 0.5% oxgall. L. acidophilus KY 2104 exerted inhibitory effect against enteric pathogens such as Escherichia coli, Shigella dysenteriae, Staphylococcus aureus and Salmonella typhimurium, when grown with each in associative cultures for 16 hr. As a result of acute toxicity of L. acidophilus KY 2104 in rats, there was no observation on motality, clinical signs, body weights and gross findings in the oral administration.

• Korean Journal of Microbiology
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• v.45 no.1
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• pp.74-81
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• 2009

In this research, we investigated the actual conditions of water purification systems at ten elementary schools located in Gunsan, Korea from July to December, 2007. The results were as follows; The population densities of heterotrophic bacteria in water purifiers ranged from 0 to $1.2{\pm}0.2{\times}10^4$ CFU/ml and those of tap water were in the range from 0 to $1.9{\pm}0.3{\times}10^4$ CFU/ml during investigation periods. Ninety percentage of purified water samples in July and September, 87.2% in October and November, and 93.7% in December turned out not to be suitable for drinking. The seasonal variation of the population densities of heterotrophic bacteria from purified waters was not notable. The total coliform, Salmonella and Shigella were not detected in purified water and tap water during investigation periods. Forty-five species of bacteria were isolated from water purifiers. The identified bacterial genera were Sphingomonas, Methylobacterium, Caulobacter, Novosphingobium, Bosea, Brevundimonas, Aminobacter, Ralstonia, Mitsuaria, Variovorax, Acidovorax, Massilia, Pseudomonas, Acinetobacter, Aeromonas, Bacillus, Staphylococcus, Brevibacillus, Microbacterium, Lapillicoccus, Micrococcus, Arthrobacter, Janibacter, Flavobacterium, Chryseobacterium, and Hymenobacter: Among the isolates, opportunistic pathogens such as Pseudomonas fluorescens, Staphylococcus epidermidis, Flavobacterium johnsoniae, and Acinetobacter johnsonii were also found.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.326-332
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• 2008

Various bacteria were isolated from Korean soil samples based on their capability inhibiting the growth of MRSA strains. Among them, strain YK5 with the highest activity was a Gram positive sporulative bacillus with motility. It did not produce indole and no acid was formed from mannitol by the bacterium. The 16S rRNA sequence of the strain showed $95{\sim}98%$ homology with those of Paenibacillus spp.. The bacterial isolate shared the highest homology with that of P. elgii (98%), but was named as Paenibacillus incheonensis YK5 due to differences in physiological properties. Butanol extract of the P. incheonensis YK5 culture grown in SST medium at $37^{\circ}C$ for 96 hr showed a broad antimicrobial activity against Gram-positive (MRSA and Streptococcus pneumoniae) and negative (Pseudomonas aeruginosa, Salmonella spp., Shigella spp., Escherichia coli, Klebsiella pneumoniae) pathogenic bacteria and fungi (Cryptococcus neoformans and Trichophyton). The antimicrobial activity in the crude extract was stable in a broad range of temperature and pH, $20{\sim}100^{\circ}C$ and $3.0{\sim}6.0$, respectively. Therefore, the antimicrobial activity of P. incheonesis YK5 had potential as a novel antibiotics for pathogens including MRSA.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.2
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• pp.124-129
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• 2016

Endotoxin, also known as lipopolysaccharide (LPS) produced by the cell wall of gram negative bacteria can be present in any liquid or on any biomaterial. Endotoxin in blood can cause fever and inflammation. In this study, we compared bacterial endotoxin using Escherichia coli O157:H7, Klebsiella oxytoca, Salmonella Typhi, Shigella sonnei and Morganella morganii. Bacteria were cultured for use in the experiment, and diluted to $1.5{\times}10^8CFU/mL$. A check marked sensitivity confirmatory test of the Limulus amebocyte lysate (LAL) reagent was performed to examine the validity. The end point reaction to each bacteria sample was confirmed with 10 fold dilution and then the final reaction end point was confirmed by 2 fold dilution between the dilution step and the upper dilution step. According to the results, in detection of endotoxins in more than 0.015 EU/mL, E. coli O157 was 75~37.5 CFU/mL, K. oxytoca 37.5~18.75 CFU/mL, M. morganii and S. Typhi 3.75~1.875 CFU/mL, and S. sonnei 7.5~3.75 CFU/mL. The resulting value was finally ensured by a confirmation test for the inhibitory factor. Based on this study, conduct of further research on bacterial endotoxin is encouraged.