• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.883-892
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• 2018

Probiotics, including Enterococcus faecium, confer a health benefit on the host. An Enterococcus strain was isolated from healthy chicken cecum, identified as E. faecium by 16S rDNA gene sequence analysis, and designated as E. faecium L11. To evaluate the potential of E. faecium L11 as a probiotic, the gastrointestinal tolerance, immunomodulatory activity, and lifespan extension properties of the strain were assayed. E. faecium L11 showed >66% and >62% survival in artificial gastric juice (0.3% pepsin, pH 2.5) and simulated small intestinal juice (0.5% bile salt and 0.1% pancreatin), respectively. Heat-killed E. faecium L11 significantly (p < 0.05) increased immune cell proliferation compared with controls, and stimulated the production of cytokines (IL-6 and $TNF-{\alpha}$) by activated macrophages obtained from ICR mice. In addition, E. faecium L11 showed a protective effect against Salmonella Typhimurium infection in Caenorhabditis elegans. In addition, feeding E. faecium L11 significantly (p < 0.05) extended the lifespan of C. elegans compared with the control. Furthermore, genes related to aging and host defense were upregulated in E. faecium L11-fed worms. In conclusion, E. faecium L11, which prolongs the lifespan of C. elegans, may be a potent probiotic supplement for livestock.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.581-586
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• 2004

The growth characteristics and the properties of the Enterococcus faecium (E. faecium) isolated from intestine of slaughting pig were examined in order to confirm whether it will be used practically as probiotics or not. E. faecium was identified by morphological and biochemical tests including of final confirming by API strep kit. Among 264 samples, 44 isolates (16.7%) of E. faecium were observed as an exellent growth as a range of $1{\times}10^7CFU/ml{\sim}3.3{\times}10^9CFU/ml$ in viable bacterial count on MRI medium. All isolates were shown non-haemolysis on the blood agar exception of 28 isolates shown ${\alpha}$-haemolysis and were identified as E. faecium by biochemical test using API strep enzyme kits. Eight strains (18.2%) were finally selected from which they were excellent sensitivity in showing of the acid-tolerance and the bile-tolerance in compare with reference strain.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.435-439
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• 2008

The antimicrobial resistance of 160 strains of Enterococcus faecalis and 173 strains of E. faecium to 12 antimicrobial agents was investigated. The test strains were isolated from 126 wild seawater and farmed fish, including olive flounder (Paralichthys olivaceus), black rock fish (Sebastes schlegeli), red sea bream (Pagrus major), and sea bass (Lateolabrax japonicus), in 2005 and 2006. Overall, 91.9% of the E. faecalis isolates and 88.4% of the E. faecium isolates showed antimicrobial resistance to at least one antimicrobial agent. The pattern of antimicrobial resistance of the isolates differed little according to the species of fish. The percentage of E. faecalis and E. faecium with specific antimicrobial resistance differed according to the sample source. For the isolates from farmed fish samples, 66.7% of E. faecalis were tetracycline resistant and 54.5% of E. faecium were erythromycin resistant. By contrast, in the wild fish seawater samples, 92.0% of E. faecalis were rifampin resistant and 88.5% of E. faecium were tetracycline resistant.

• Food Science of Animal Resources
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• v.28 no.1
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• pp.99-104
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• 2008

A lactic acid bacterium showing growth inhibitory activity against Enterobacter sakazakii was isolated from bovine intestinal tracts. From biochemical and molecular biological studies, the isolate was identified and named as Enterococcus faecium JH95. This strain was resistant to kanamycin and streptomycin at a concentration of $100{\mu}g/mL$. E. faecium JH95 had high antimicrobial activity against food-borne pathogens such as Escherichia coli O157:H7, Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, and Clostridium perfrigens. The culture supernatant of this strain did not have antimicrobial activity. The culture broth of this strain failed to show the antimicrobial activity by heat treatment at $100^{\circ}C$ for 5 min or by pretense treatments for 2 hr. This result suggested that the putative antimicrobial substance produced by E. faecium JH95 is likely a protein which is not secreted into culture medium.

• Journal of Life Science
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• v.27 no.2
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• pp.172-179
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• 2017

The fermentation of Panax ginseng can yield many compounds from ginsenosides that have a wide variety of biological functions. Lactic acid bacteria (LAB) strains are capable of converting ginsenosides. The purposes of this study were to: (1) characterize Enterococcus faecium SA5, an isolated LAB from Mongolian mare milk, (2) identify the existence of extracellular ${\beta}$-glucosidase activity in the milk, and (3) ascertain if the ${\beta}$-glucosidase has the capacity of converting ginsenoside in Korean ginseng. The results revealed that E. faecium SA5 was acid-resistant, bile salt-resistant, and has antibiotic activities against 4 pathogenic microorganisms (Salmonella typhimurium KCTC 3216, Listeria monocytogenes KCTC 3710, Bacillus cereus KCTC 1012, Staphylococcus aureus KCTC 1621). In addition, E. faecium SA5 had tolerance against some antibiotics such as colistin, gentamycin and neomycin. It was also found that E. faecium SA5 possessed bile salt hydrolase activity, which could lower blood cholesterol level. When incubated in 10% (w/v) skim milk as a yogurt starter, E. faecium SA5 caused to decrease pH of the medium as well as increase in viable cell counts. Using TLC and HPLC analysis on the samples incubated in MRS broth, our study confirmed that E. faecium SA5 can produce ${\beta}$-glucosidase, which was capable of converting ginsenoside $Rb_1$ into new ginsenosides $Rg_3-s$ and $Rg_3-r$. It was concluded that E. faecium SA5 possessed a potential of probiotic activity, which could be applied to yogurt manufacture as well as ginsenoside conversion in ginseng.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.516-520
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• 2018

Bacteriocin is a proteinaceous compound produced by microorganisms showing antimicrobial activities. In this study, the physicochemical properties of the bacteriocin produced by Enterococcus faecium CJNU 2008 strain were characterized. Partially purified bacteriocin showed stabilities against heat treatments at $100^{\circ}C$ for 30 min and $121^{\circ}C$ for 15 min and against solvents treatments such as methanol, ethanol, acetone, acetonitrile and chloroform. The bacteriocin also exhibited stabilities against lipase and ${\alpha}-amylase$ treatments but the stability was abolished at protease treatment, indicating that the antimicrobial agent from E. faecium CJNU 2008 was a proteinaceous bacteriocin. The bacteriocin also showed bactericidal mode of action against Listeria monocytogenes. The molecular mass of the bacteriocin was estimated to be under 6.5 kDa by a tricine-SDS-PAGE analysis. The bacteriocin was purified by HPLC. Further studies toward biochemical analysis of the bacteriocin are needed in near future.

• The Korean Journal of Food And Nutrition
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• v.33 no.3
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• pp.223-236
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• 2020

In this study, a safety evaluation was conducted to confirm if the Enterococcus faecium CKDB003 strain obtained by selection from a mixed fermentation of fruit and milk is suitable for use as a probiotic. The MIC value for the 10 antibiotics specified in the EFSA guidance was below the acceptable cut-off value. The antibiotic resistance genes aac(6')-li, eatAv, and msr(C) exist by whole genome sequencing, but are in the chromosome and not in the plasmid, thus confirming that there is no possibility of transmission to other microorganisms. It was confirmed that cytolysin (cylA, cylB, cylI, cylL-l, cylL-s, cylM, cylR1, cylR2), aggregation substance (asa1, asp1), collagen adhesion (ace), enterococcal surface protein (esp), endocarditis antigen (efaA), hyaluronidase (hyl) and gelatinase (gelE) were not present in the genome by examining the genes of factors related to virulence. Also, the biochemical analysis showed no toxic enzyme activities, and no virulence genes were detected by the PCR method. Thus, the E. faecium CKDB003 strain can be safely used as a health functional food probiotic, based on the results of the safety assessment.

• Microbiology and Biotechnology Letters
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• v.36 no.2
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• pp.142-148
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• 2008

To evaluate the antibiotic resistance of Enterococcus from salad and sprout, Enterococcus were isolated and identified from 47 salad samples and 37 sprout samples, and then their antibiotic resistances were analyzed. Ninety five Enterococcus, 41 strains from salad and 54 strains from sprout, were ultimately isolated. The frequent Enterococcus in salad and sprout were E. gallinarum, E. faecalis, E. faecium, E. hirae, and E. avium. Minimum inhibitory concentrations of the isolates for vancomycin were below $4{\mu}g/mL$, which were not high levels of resistance. All Enterococcus proved to be resistant to streptomycin and chloramphenicol. Twenty two percentage of the isolates were resistant to penicillin, however, almost the isolates were sensitive to tetracycline. Eighteen percentage of the isolates were resistant to erythromycin. All E. faecium and E. faecalis were found to be ampicillin-resistant, and seven E. faecalis and five E. faecium were resistant to rifampicin. Overall antibiotic resistances of Enterococcus isolates were relatively low and low resistance to vancomycin was similar to those evidenced by Enterococcus isolated from the other foods. Therefore, there may be no special risk from the antibiotics resistances of Enterococcus and especially vancomycin-resistant Enterococcus from the fresh-cut salads and the sprouts.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.133-138
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• 2013

In this study, a total of 256 samples of retail raw meats (beef, pork and chicken) and sashimi were investigated for the presence of Enterococcus faecalis and Enterococcus faecium. We isolated a total of 117 E. faecalis and E. faecium from the samples, with contamination rates ranging from 18.8% for sashimi samples to 68.8% of chicken samples. E. faecalis was the predominant species recovered from all of the retail raw meats beef (42.2%), pork (42.2%), chicken (65.6%) and sashimi (12.5%). Among 117 isolates, 61 isolates (52.1%) were resistant to tetracycline, 32 isolates (27.4%) were resistant to erythromycin, 23 isolates (19.7%) were resistant to chloramphenicol, 16 isolates (13.7%) were resistant to ripampin, 10 isolates (8.5%) were resistant to gentamycin, 9 isolates (7.7%) were resistant to ciprofloxacin and 1 isolate (0.9%) was resistant to ampicillin and penicillin G. No resistance to amoxicillin + clavulanic acid and vancomycin was observed. Although no strain was resistant to vancomycin, the vanB gene was observed in 9 of 117 of Enterococcus (7.7%) demonstrating potential risk of vancomycin-resistant Enterococcus (VRE). Our results indicate that E. faecalis and E. faecium were highly prevalent in retail raw meats, but most strains were sensitive to tested antibiotics.

• Journal of Periodontal and Implant Science
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• v.38 no.1
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• pp.31-40
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• 2008

Purpose: The probiotic effects of lactic acid bacteria have widely been researched in diverse human pathogens, but only a few effects are reported against oral pathogens. The antimicrobial effects of the Enterococcus faecium 7413 isolated from Korean infants on the 9 pathogen including 6 oral streptococci were investigated the clinical use of the antimicrobial peptide for oral microflora control. Materials and Methods: E. faecium 7413 was identified by morphological, biochemical tests and 16S rDNA sequence analysis. Inhibitory effects of culture supernatants were determined for their ability to grow on agar plate containing pathogenic bacteria. Result: The culture supernatant of Enterococcus faecium 7413 showed inhibitory effects on oral pathogens, namely Streptococcus pyogenes KCTC 3556, S. pneumoniae KCTC 5080, S. mutans ATCC 25175, S. anginosus ATCC 33397, S. constellatus KCTC 3268, S. intermedius ATCC 27823 and Shigella flexneri KCTC 2008. Whereas it did not affect the multiplication of E. coli strains, KCTC 1041 and ATCC 43894. Conclusion: The data obtained in this study could be useful for future development of effective probiotics allowing prevention for oral pathogens.