• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.247-259
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• 2008

Terminal-restriction fragment length polymorphism (T-RFLP) analysis, one of rapid culture-independent microbial community analysis methods, was used to determine the lactic acid bacterial complexity and dynamics during kimchi fermentation at $15^{\circ}C$ and $4^{\circ}C$. At both temperatures, the common presence of Leuconostoc mesenteroides, Lc. inhae, Lc. kimchi, Weissella koreensis, W. cibaria, Lactobacillus sakei, Lb. curvatus, Lb. plantarum, Lb. paraplantarum, Lb. pentosus, and Lb. brevis was predicted. Lc. citreum and Enterococcus faecalis were detected at $15^{\circ}C$ and $4^{\circ}C$, respectively. W. koreensis predominated during the mid stage of kimchi fermentation whereas lactobacilli were dominants during later stage. Lb. sakei and Lb. curvatus became dominants regardless of fermentation temperature but the growth of Lb. plantarum, Lb. paraplantarum, Lb. pentosus, and Lb. brevis was restricted at psychrophilic temperature. Some species of leuconostocs were maintained until the later stage of kimchi fermentation.

• 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.

• Biomedical Science Letters
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• v.1 no.1
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• pp.55-72
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• 1995

Forty gentamicin-resistant isolates of Enterococcus faecalis were selected from various clinical materials, determined their antimicrobial susceptibility, and studied there R-plasmid characteristics and polypeptide patterns. All of the isolates were susceptible to vancomycin. The MICs($\mu$/ml) of antimicrobial agents to the isolates were as follows; the MIC of gentamicin was 128 and $\geq$2040, ampicillin 1 and 1, chlorarmphenicol 2 and 8, erythromycin 32 and 256, and vancomycin 1 and 2. E. faecalis HL-1 strain had 8 plasmid DNA elements, HL-2 and HL-3 strains had 6, HL-4 had 7, HL-5 had 4, and HL-6 had 5. The 51.7 Kb of gentamicin resistance plasmid DNA was conjugally transferred from two strains of E. faecalis HL-1 and HL-6 to S. aureus SK 982. The plasmid transfer frequency between S. aureus SK 982 and E. faecalis HL-1 or E. faecalis HL-6 was 6.3$\times10^{-4} and 3.7$\times10^{-5}$, respectively. Plasmid curing ratio after the treatment of ethidium bromide(10$\mu$/ml) to E. faecalis tarnsconjugants R-1 and R-6 were about 51% and 67%, respectively. The tetracycline gene was located in 2.15 Kb plasmid of E. faecalis HL-1, but it was not found in the E. faecalis HL-6 by Southern blot analyses. The antigenic components of E. faecalis HL-1, HL-6, R-1 and R-6 strains were analyzed by SDS-PAGE and immunoblotting. The E. faecalis strains had 7 to 16 polypeptide bands, however their major proteins were 97.8 and 26.8 Kd. At the Immunoblotting, 97.8, 95.8, 74.8, 63.5, 33.7 and 26.8 Kd polypeptides of the strains showed major antigenic activities with patient's sera infected intra-abdominally with an E. faecalis strain.

• Journal of Life Science
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• v.33 no.6
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• pp.481-489
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• 2023

The taste and quality of soy sauce, a fermented liquid condiment, is greatly influenced by microbial metabolism during fermentation. To investigate the microbiological characteristics of ganjang during the initial fermentation process, we prepared meju (fermented soybean) blocks fermented with starter cultures and solar salts and analyzed the microbial community quantitively using 16S rRNA gene profiling from ganjang that had been fermented over a five-week period. The ganjang samples were collected and analyzed after soaking for week one (1W), three (3W), and five (5W) weeks. We found that Halomonadaceae was significantly higher in the 1W group (89.83%) than the 3W and 5W groups (14.46%, and 13.78%, respectively). At a species level, Chromohalobacter beijerinckii and Chromohalobacter canadensis were the dominant species in the 1W group but several taxa such as Bacillus subtilis, Pediococcus acidilactici, and Enterococcus faecalis were more abundant in the 3W and 5W groups. Pearson correlation analysis of the relative abundance of the bacteria showed a negative correlation between Chromohalobacter and two bacterial genera Bacillus and Enterococcus. Beta-diversity showed a statistical distinction between the 1W and the 3W and 5W groups, while no significance was evident between the 3W and 5W groups. Linear discriminant effect size analysis was used to identify biomarkers and significant differences in the relative abundance of several halophilic bacteria, Bacillus sp. and lactic acid bacteria at 1W, 3W, and 5W, recpectively, which indicates the important role of the bacterial community at these time points.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.129-136
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• 2011

Microorganisms are the main causative factors of pulpal and periapical diseases, therefore successful endodontic treatment is depend on the effective elimination of intracanal bacterial populations. Many studies have been reported antimicrobial effect of Allyl isothiocyanate (AIT) which the principle ingredient of Horseradish (Armoracia rusticana) root extracts. The purposes of this study are to evaluate the antimicrobial effectiveness of Horseradish root extracts against Enterococcus faecalis in root canals of extracted human teeth and compare to sodium hypochlorite (NaOCl). Extracted human mandibular premolar root canals were infected with E. faecalis for 21 days, and then irrigated with Horseradish root extracts, NaOCl solution and saline. After canal irrigation, first samples (S1) were taken. After first sampling, the canals were additionally incubated 7 days, and then second samples (S2) were taken. The samples were inoculated on EHI agar plate to determine the colony forming units (CFU). 1. Mean values of CFU in S1 were $5.815{\times}10^3$ CFU/ml at Horseradish groups, and $3.465{\times}10^3$ CFU/ml at NaOCI groups. There was no statistically significant differences (p=0.086). 2. Mean values of CFU in S2 were $3.100{\times}10^3$ CFU/ml at Horseradish groups, and $5.252{\times}10^5$ CFU/ml at NaOCI groups. There was statistically significant difference (p<.05). 3. There was no statistically significant differences (p=0.076) between S1 and S2 at Horseradish groups in the mean values of CFU. However, there was statistically significant differences (p<.05) between S1 and S2 at NaOCI groups in the mean values of CFU.

• Restorative Dentistry and Endodontics
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• v.34 no.6
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• pp.500-507
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• 2009

The purpose of this study is to compare the antibacterial effect of $Listerine^{(R)}$ on two microorganisms (P. gingivalis and E. faecalis) with various root canal irrigants (NaOCl, CHX, EDTA) and to identify possibility of using $Listerine^{(R)}$ as a root canal irrigant. Porphyromonas gingivalis ATCC 3327 and Enterococcus faecalis ATCC 29212 were used in this experiment. For the test irrigants, 0.5%, 1%, 2.5%, 5.25% NaOCl, 0.1%, 0.2%, 1%, 2% CHX, 0.5M EDTA (18.6% EDTA) and $Listerine^{(R)}$ were prepared. Distiled water was used as control. Two methods-1) Comparison of turbidity in broth and 2) Agar diffusion test-were used to determine the extent of antibacterial effect of $Listerine^{(R)}$ and to compare it with that of NaOCl, CHX, and EDTA. All solutions tested were effective against two bacterial strains compared with control (p < 0.001). Any concentration of NaOCl, CHX, and EDTA showed similarly high effectiveness against all bacterial strains. In all experiment, $Listerine^{(R)}$ showed significantly low antibacterial effect compared with the other root canal irrigants (p < 0.05). In conclusion, the results reflect remarkably low antibacterial effect of $Listerine^{(R)}$ as compared with root canal irrigants in general so it is not suitable for the root canal irrigant.

• Journal of Life Science
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• v.27 no.10
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• pp.1168-1175
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• 2017

Probiotics are usually defined as intestinal bacteria that provide healthy benefit to the host and may offer new therapeutic materials for the treatment of inflammatory diseases. Lactobacillus, Bifidobacterium and Enterococcus are known as typical probiotics. But, these bacteria have mostly a weak viability and thus decreased probiotics-mediated effects in the intestinal tract. Asthma is an inflammatory airway disease, which is characterized by the releases of inflammatory mediators including cytokine and IgE. They are mainly associated with the recruitment, activation and disregulation of specific inflammatory cells, especially mast cells, monocytes, T cells, eosinophils and neutrophils in asthma. We performed these studies as in vitro and in vivo test the human inflammatory cell lines and ovalbumin (OVA)-induced asthma mouse model. And then the inhibitory effects of Enterococcus faecalis whole extract on inflammatory responses were examined. For our examinations, the E. faecalis whole extract (Ef extract) was acquired from whole bacteria of E. faecalis using freeze/thawing after ultrasonication method. As results, OVA-mediated THP-1 cell viability was decreased by the treatment of Ef extract. In the asthmatic mouse model, Ef extract inhibited the infiltration of inflammatory cells into the inflammatory sites and blood. This whole extract may have anti-asthmatic effects associated with the regulation of IL-5 and IgE expression. It may also be a promising candidate in anti-allergic medicine for the treatment of asthma.

• Journal of Dairy Science and Biotechnology
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• v.38 no.2
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• pp.70-88
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• 2020

Lactic acid bacteria (LAB) form an essential part of the intestinal microbiota of the human body and possess the ability to stabilize the intestinal microbiota, strengthen immunity, and promote digestion as well as intestinal synthesis of vitamins, amino acids, and proteins. Hence, LAB are currently widely used in various products. However, due to the indiscriminate overuse of antibiotics in humans and livestock, bacterial resistance to antibiotics has been increasing rapidly, which has led to serious problems in the treatment of bacterial infections. Additionally, several reports have revealed that antibiotic-resistant LAB may infect people whose immune systems are not fully developed or whose immune systems are temporarily weakened. Therefore, it is imperative to consider the possibility of antibiotic-resistant LAB causing diseases in humans and animals, investigate the mechanism of action between antibiotics and LAB, and determine the relevant regulations for the safe use of LAB.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.899-904
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• 2002

Aloe and propolis are extensively used in folk medicine. Ethanol extracts of Aloe vera (AE), ethanol extract of propolis (PE) and waxfree extract of propolis (PW) were prepared to test antimicrobial activities against five oral microorganisms (Streptococcus mutans, Enterococcus faecalis, Enteococcus hirae, Escherichia coli, Candida albicans). Antimicrobial activities were tested by serial broth dilution method and expressed by minimal inhibitory concentration (MIC). The AE showed relatively weak antimicrobial activities, while both of PE and PW greatly inhibited all microorganisms tested. To investigate the antimicrobial effects of the combined extracts of aloe with propolis, the fractional inhibitory concentration index (FICI) was determined by checkerboard assay for each strain. The combination of AE with PE or PW resulted in Synergistic effect against oral microorganisms tested (FICI=0.375) except Escherichia coli (FICI=1.0 for PE, FICI=0.75 for PW).

• Korean Journal of Clinical Laboratory Science
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• v.54 no.4
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• pp.273-278
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• 2022

This study evaluates the improved effect of photodynamic therapy (PDT) by subjecting pathogenic bacteria to a combination of 630 nm light-emitting diode (LED) and 5-aminolevulinic acid (ALA). Bacterial suspensions of 1.5×10⁴ cells/mL were diluted and exposed to ALA concentrations of 10, 5, 2.5, 1.25, and 0.625 mg/mL, incubated for 30 minutes, followed by irradiation with 630 nm LED (18 J/cm² ). The non-irradiated P. aeruginosa group and the group administered only LED light averaged 415 and 245 colonies, respectively. Conversely, the PDT group showed an average of 109, 225, 297, and 285 colonies at concentrations of 10, 5, 2.5, and 1.25 mg/mL of ALA. Evaluating the effect on E. faecalis revealed an average of 8,750 and 8,000 colonies in the group that did not receive the control photosensitizer and the group exposed to light alone, respectively. However, an average of 0, 2350, 4825, and 7475 colonies at concentrations of 5, 2.5, 1.25, and 0.625 mg/mL ALA were determined for the PDT groups. In conclusion, better inhibitory effects were observed for E. faecalis than for P. aeruginosa. Moreover, our results validate the possibility of improved PDT efficacy using a combination of ALA and 630 nm LED.