• Korean Journal of Microbiology
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• v.50 no.1
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• pp.73-83
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• 2014

The objective of the this study was to investigate the binding capacity and removal ability of lactic acid bacterial strains obtained from Korean soybean paste for mutagenic heterocyclic amines (HCAs) formed during cooking of protein-rich food at high temperature. Among 19 strains identified by carbohydrate fermentation and 16S rRNA sequencing, the live cell or cell-free culture supernatant of Lactobacillus acidophilus D11, Enterococcus faecium D12, Pediococcus acidilactici D19, L. acidophilus D38, Lactobacillus sakei D44, Enterococcus faecalis D66, and Lactobacillus plantarum D70 inhibited the mutagenesis caused by either 3-amino-1,4-dimethyl-5H-pyrido[4,3-b] indole (Trp-P-1) or 3-amino-1-methyl-5H-pyrido[4,3-b] indole (Trp-P-2) in Salmonella typhimurium TA98 and TA100. The bacterial cells of the isolated strains showed greater binding activity than the pure cell wall, exopolysaccharide, and pepetidoglycan. The carbohydrate moieties of the cell wall or protein molecules on the cell surface have a significant role in binding Trp-P-1 and Trp-P-2, since protease, heating, sodium metaperiodate, or acidic pH treatments significantly (P<0.05) reduced the binding efficacy of the tested bacteria. Addition of metal ions or sodium dodecyl sulfate decreased the binding ability of E. faecium D12, L. acidophilus D38, and E. faecalis D66. Therefore, the binding mechanisms of these strains may consist of ion-exchange and hydrophobic bonds. Especially, the high mutagen binding by L. acidophilus D38 and L. plantarum D70 may reduce the accumulation or absorption of Trp-P-1 and Trp-P-2 in the small intestine via increased excretion of a mutagen-bacteria complex.

• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.360-366
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• 2013

This study was it conducted on effluent or river water close to discharge locations from a treatment plant, which were analyzed for the presence, phenotype and antibiotic resistance rates of Vancomycin Resistant Enterococci (VRE). The test results for isolation and identification of Enterococcus spp. showed that they all were VRE positive, with a total of 32 strains detected. Multiplex PCR was conducted for 32 strains, each of which were identified as E. faecium, and the results indicated that they were all confirmed as VRE, corresponding to the Van A phenotype. The results of E. faecium concentrations measured at various locations indicated that they were, on average, higher at the location of sewage treatment plants. The frequency of positive tests as well as the number of colonies was higher downstream of treatment plants. The minimum inhibitory concentration was inspected for 26 strains of discharged water samples from sewage water treatment plants, and 6 strains of river samples. Out of 19 antibiotics, 14 and 5 species showed resistance and sensitivity, respectively.

• Microbiology and Biotechnology Letters
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• v.35 no.3
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• pp.210-219
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• 2007

In this study was investigated the growth effect of native plant (Microlepia marginata(panzer Christ., Prunella vulgaris. aleutica Fernald, Perillafrutescens var. japonica Hara., Gleichenia japonica Spreng) extracts on various lactic acid bacterias, electron donating ability, total cell count and hydroxyl radical scavenging activity. The total cell count of Enterococcus faecium KCCM 12118, Lactobacillus rhamnosus KCCM 32826, Lactobacillus plantarum KCCM 11542, Pediococcus pentosaceus KCCM 40464 in the absence of native plant extracts (10%) at $37^{\circ}C$ after 48hr were $2.2{\times}10^9\;cfu/ml$, $2.1{\times}10^9\;cfu/ml$, $2.3{\times}10^9\;cfu/ml$, $2.2{\times}10^9\;cfu/ml$. On the other hand, the total cell count of E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCCM 11542, P. pentosaceus KCCM 40464 in the presence of native plant extracts (10%) at $37^{\circ}C$ after 48hr were $4.3{\times}10^9\;cfu/ml$, $4.3{\times}10^9\;cfu/ml$, $4.8{\times}10^9\;cfu/ml$, $3.9{\times}10^9\;cfu/ml$. The electron donating ability indicated to E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCCM 11542, P. pentosaceus KCCM 40464 added by 10% native plant extracts, respectively. when 10% native plant extracts were added lactic acid bacterias, the electron donating ability is the highest. Hydroxyl radical scavenging activity of E. faecium KCCM 12118, L. rhamnosus KCCM 32826, L. plantarum KCCM 11542, P. pentosaceus KCCM 40464 showed higher than that of control.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.470-476
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• 2007

To evaluate the vancomycin resistance of Enterococcus spp. (VRE) from Saengsik and Sunsik, Enterococcus were isolated and identified from 25 Saengsik and 35 Sunsik samples, and resistance of Enterococcus to other antibiotics was also assessed. Thirty nine Enterococcus, 16 strains from Saengsik, and 23 strains from Sunsik, were ultimately isolated. The most frequently collected Enterococcus isolates in Saengsik were E. casseliflavus and E. hirae, and were E. casseliflavus and E. faecium in Sunsik. However, E. faecalis was not detected in those foods. Minimum inhibitory concentrations of vancomycin against the isolates were below $4\;{\mu}g/mL$ and no strains evidenced profound levels of resistance. The isolates were found to be susceptible to vancomycin with the exception of eight E. casseliflavus and three E. gallinarum. All Enterococcus isolates proved resistant to streptomycin and chloramphenicol. 23% of the isolates were resistant to penicillin; however, all of the isolates were sensitive to tetracycline. Six and 48%, respectively, of the strains from the Saengsik and Sunsik proved resistant to erythromycin. All of E. mundtii and E. hirae isolates from Saengsik, and 20% of E. gallinarum and E. casseliflavus isolates from Sunsik were found to be ampicillin-resistant. All of E. gallinarum, E. casseliflavus, and E. faecium were rifampin-resistant. The antibiotic resistances of Enterococcus were relatively low, and this low vancomycin resistance was similar to that evidenced by Enterococcus isolates obtained from the other foods. However, there may be a need for some review of the accepted antibiotics criteria for Enterococcus and VRE in ready-to-eat foods.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.4
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• pp.296-303
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• 2005

A strain named as HJ35 was isolated from the skin of sixty-five men and fourteen women for acne therapy, in order to find an effective antimicrobial agent against Propionibacterium acnes. Isolate HJ35 was identified as Enterococcus faecium based on 16 rDNA sequence and produced enterocin HJ35 having antimicrobial activities against most lactic acid bacteria, En­terococcus spp., Staphylococcus aureus, S. epidermidis, Clostridium perfringens, some bacilli, Mi­crococcus flavus, Listeria monocytogenes, L. ivanovii, Escherichia coli, Pseudomonas fluorescens and Propionibacterium acnes, in the modified well diffusion method. Especially, enterocin HJ35 showed a bactericidal activity against Propionibacterium acnes P1. The antimicrobial activity of enterocin HJ35 was disappeared completely with the use of protease XIV. But enterocin HJ35 activity is very stable at high temperature (up to $100^{\circ}C$ for 30 min), in wide range of pH (3.0${\~}$9.0), and by treatment with organic solvents. The apparent molecular mass of enterocin HJ35 was estimated to be approximately 4${\~}$4.5 kDa on detection of its bactericidal activity after SDS-PAGE. In batch fermentation of E. faecium HJ35, enterocin HJ35 was produced at the mid­log growth phase, and its maximum production was obtained up to 2,300 AU/mL at the late stationary phase. By employing fed-batch fermentation, the enhanced production of enterocin HJ35 was achieved up to 12,800 AU/mL by feeding with 10 g/L glucose or 6 g/L lactate.

• Journal of Microbiology and Biotechnology
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• v.31 no.2
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• pp.181-188
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• 2021

Bacillus subtilis and Enterococcus faecium are commonly used probiotics. This study aimed to identify the effect of live combined Bacillus subtilis R0179 and Enterococcus faecium R0026 (LCBE) on obesity-associated hyperlipidemia and gut microbiota in C57BL/6 mice. Forty male C57BL/6 mice were divided into four groups: normal group (N group), model group (M group), low-dose group (L group), and high-dose group (H group). Mice were gavaged with LCBE at 0.023 g/mice/day (L group) or 0.23 g/mice/day (H group) and fed with a high-fat diet for 8 weeks. In vitro E. faecium R0026 showed an ability to lower the low-concentration of cholesterol by 46%, and the ability to lower the high-concentration of cholesterol by 58%. LCBE significantly reduced the body weight gain, Lee index, brown fat index and body mass index of mice on a high-fat diet. Moreover, LCBE markedly improved serum lipids (including serum triglyceride, total cholesterol, low-density lipoprotein and high-density lipoprotein) while also significantly reducing liver total cholesterol. Serum lipopolysaccharide and total bile acid in L and H groups decreased significantly compared with M group. PCR-DGGE analysis showed that the composition of gut microbiota in the treatment groups was improved. Akkermansia muciniphila was found in H group. The PCA result indicated a similar gut microbiota structure between LCBE treatment groups and normal group while the number of bands and Shannon diversity index increased significantly in the LCBE treatment groups. Finally, qPCR showed Bifidobacterium spp. increased significantly in H group compared with M group, LCBE alleviated liver steatosis and improved brown adipose tissue index.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.359-363
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• 2019

Meju is a spontaneously fermented soybean product produced in Korea. We isolated the bacteria of the genera Bacillus, Enterococcus, and Staphylococcus from 12 meju samples collected from five regions of Korea using selective media, and we identified them based on the sequence analysis of 16S ribosomal RNA and gmk (guanylate kinase) genes. Bacillus and Enterococcus strains were identified from all samples and the numbers of Bacillus strains in the 11 samples were >15% of the total cell number. Therefore, the genus Bacillus was confirmed as the predominant bacterial group of meju. Staphylococcus strains were identified from six samples. The identified 151 Bacillus isolates predominated in the following order: B. velezensis, B. sonorensis, B. subtilis, and B. licheniformis. Among the 165 Enterococcus isolates, 163 strains were identified as E. faecium. Eighty-two Staphylococcus isolates were classified into six species of coagulase-negative Staphylococcus group and S. xylosus was the predominant species.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.194-198
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• 2015

Enterococcus faecalis is a Gram-positive and facultative anaerobic bacterium that causes many hospital-acquired infections. Novel E. faecalis specific bacteriophage (phage) ECP3 that had been isolated from thirty-four environmental samples and characterized phenotypically and genotypically. ECP3 phage belongs to the family Myoviridae with contractile tail and lysed E. faecalis specifically but other bacteria including Enterococcus faecium. The genome was double-stranded linear DNA and its size was 145,518 bp comprising of 220 open reading frames. The GC content was 35.9%. The genome sequence showed 97% identity in 90% coverage region with Myoviridae phage PhiEF24C. ECP3 is the first E. faecalis-specific Myoviridae phage isolated in Korea which can be a promising antimicrobial agent against E. faecalis infections.

• Biomedical Science Letters
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• v.21 no.2
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• pp.84-91
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• 2015

To provide guidelines for the empirical treatment of urinary tract infections, we observed annual changes in the occurrence frequency and antimicrobial susceptibility of urinary isolates in a university hospital in the Chungbuk province, South Korea, over a period of 10 years (2004~2013). Escherichia coli (38.2%), Enterococcus faecalis (11.7%), Klebsiella pneumoniae (7.3%), Pseudomonas aeruginosa (4.3%), E. faecium (4.3%), and Staphylococcus aureus (4.1%) were commonly isolated urinary pathogens. The prevalence of E. coli, E. faecium and Streptococcus agalactiae were significantly higher in females (P < 0.001), whereas E. faecalis, P. aeruginosa and S. aureus were significantly more common in male patients (P < 0.001). E. coli mostly frequently showed resistance to ampicillin (67.94%), followed by trimethoprim/sulfamethoxazole (36.06%) and ciprofloxacin (26.84%). Over the studied time period, resistance rates of E. coli to ciprofloxacin significantly increased (20.44% to 33.55%). Moreover, extended-spectrum $\beta$-lactamase (ESBL) producing isolates also significantly increased in E. coli (4.2% to 18.3%) and K. pneumoniae (9.6% to 26.9%). In addition, the proportion of vancomycin-resistant Enterococcus facium (VRE) also increased (15.7% to 25.0%). In conclusion, over the last 10 years, the proportions of ciprofloxacin resistant E. coli and multidrug-resistant bacteria, such as ESBL and VRE have significantly increased. This trend must be strictly controlled and demonstrates the need for more updated guidelines for the treatment of urinary tract infections.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.373-377
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• 2009

From April 2008 to January 2009, a total 458 raw milk samples were randomly collected from 15 stock raising farms located in northern area of Kyunggi province and cultured for the presence of Enterococci spp. A total 170 enterococcal isolates were recovered from the raw milk samples. Enterococcus faecalis was predominant species recovered (64.7%), followed by E. faecium (18.8%), E. avium (5.9%), E. gallinarum (5.9%) and E. durans (4.7%). Antimicrobial resistance patterns of 170 Enterococci spp. against ampicillin, erythromycin, tetracyclin, chloramphenicol, vancomycin, ciprofloxacin and streptomycin were tested. According to the result, they showed high level resistance to erythromycin and streptomycin (82,9% and 93,5% respectively), moderately resistance to ampicillin, chloramphenicol and tetracyclin (50%, 45.9% and 32%, respectively) but fortunately, vancomycin and ciprofloxacin are still effective against this species.