• 한국식품조리과학회지
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• 제16권4호
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• pp.358-362
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• 2000

1. 보리에서 분리한 균주는 Gram 양성의 구균으로 미생물 동정기를 이용하여 동정해 본 결과 Enterococcus mundtii와 89%의 상동성을 보여 이 균주는 Enterococcus 속으로 동정되었다. 2. 초기 pH는 모두 5.5였으며 시간이 경과함에 따라 가장 먼저 pH가 떨어지기 시작한 것은 Lactobacillus sanfrancisco이였으며 다음으로 Enterococcus mundtii와 Lactobacillus plantarum의 순이였다. pH 4.5까지 떨어지는데 걸리는 시간도 Lactobacillus sanfrancisco이 8시간 10분으로 가장 짧았으며 Enterococcus mundtii는 9시간 30분이였으며 Lactobacillus plantarum은 9시간 50분의 순이었다. 동일한 pH에서 산도는 Lactobacillus sanfrancisco가 가장 산도가 높았으며 Entercoccus mundtii, Lactobacillus plantarum의 순이었다. 3. 대조군에 비해 균주가 혼합된 식빵 3개 모두 부피가 커졌으며 이중 Lactobacillus sanfrancisco가 가장 부피가 컸으며 대조군에 비해 11%정도 부피가 증가하였다. 부피를 무게로 나눈 용적비도 부피와 같은 경향을 보였다. 식빵의 높이는 Lactobacillus sanfrancisco와 Enterococcus mundtii이 가장 컸고 다음이 Lactobacillus plantarum, 대조군의 순이었다. 4. 96시간 경과 시 대조군에만 곰팡이가 발견되었고 다른 군에서는 144시간 이후에도 곰팡이가 발견되지 않았다. 경도는 시간경과에 따라 지속적으로 증가하였으며 경도가 가장 낮은 Lactobacillus sanfrancisco와 다음으로 낮은 Enterococcus mundtii의 경우 초기에는 경도 변화가 별로 없었다가 48시간 경과 시 경도가 증가하였다.

• 한국미생물·생명공학회지
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• 제52권2호
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• pp.163-178
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• 2024

Pan-genome analysis is used to interpret genome heterogeneity and diversification of bacterial species. Here, we present pan-genome analysis of 22 strains of Enterococcus mundtii. The GenBank file of E. mundtii strains that have been isolated from different sources i.e., human fecal matter, soil, leaf, dairy products, and insects was downloaded from National Center for Biotechnology Information (NCBI) database and analyzed using BPGA-1.3.0 (Bacterial Pan Genome Analysis) pipeline. Out of a total, 4503 gene families, 1843 belongs to the core genes whereas 1,762 gene families represent the accessory genes and 898 gene families depict the unique genes among all the selected genomes. Majority of the core genes belongs to the categories of Metabolism (37.83%) and Information storage & processing (29.84%) whereas unique genes belongs to the category of Information storage & processing (48.08%). Further, accessory genes are almost equally present in both functional categories i.e. Information storage & processing and Metabolism (34.34% and 32.27% respectively). Further, subset analysis on the basis of the origin of isolates exhibits presence and absence of exclusive gene families. The observation suggests that even closely related strains of a species show extensive disparity in genome owing to their ability to adapt to a specific environment.

• Food Science and Biotechnology
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• 제16권3호
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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.

• 한국축산식품학회지
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• 제37권5호
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• pp.670-681
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• 2017

The aim of this study was to isolate enterococci in Sucuk, a traditional Turkish dry-fermented sausage and to analyze isolates for their biodiversity, antibiotic resistance patterns and the presence of some antibiotic resistance genes. A total of 60 enterococci strains were isolated from 20 sucuk samples manufactured without using a starter culture and they were identified as E. faecium (73.3%), E. faecalis (11.7%), E. hirae (8.3%), E. durans (3.3%), E. mundtii (1.7%) and E. thailandicus (1.7%). Most of the strains were found resistant to rifampin (51.67%) followed by ciprofloxacin (38.33%), nitrofurantoin (33.33%) and erythromycin (21.67%). All strains were found susceptible to ampicillin. Only E. faecium FYE4 and FYE60 strains displayed susceptibility to all antibiotics. Other strains showed different resistance patterns to antibiotics. E. faecalis was found more resistant to antibiotics than other species. Most of the strains (61.7%) displayed resistance from between two and eight antibiotics. The ermB, ermC, gyrA, tetM, tetL and vanA genes were detected in some strains. A lack of correlation between genotypic and phenotypic analysis for some strains was detected. The results of this study indicated that Sucuk manufactured without using a starter culture is a reservoir of multiple antibiotic resistant enterococci. Consequently, Sucuk is a potential reservoir for the transmission of antibiotic resistance genes from animals to humans.

• Asian-Australasian Journal of Animal Sciences
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• 제28권5호
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• pp.620-631
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• 2015

A total of 59 lactic acid bacteria (LAB) strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA) sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L.) plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC $43971^T$, Micrococcus luteus ATCC $4698^T$ and Escherichia coli ATCC $11775^T$ were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at $100^{\circ}C$), but the antimicrobial activity was eliminated after treatment at $121^{\circ}C$ for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0), but became inactive under neutral and alkaline condition (pH 7.0 to 9.0). In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory.

• International Journal of Industrial Entomology and Biomaterials
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• 제48권1호
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• pp.42-47
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• 2024

The value of silkworms as functional health food materials has increased, as has the interest in its disease control for stable production, and in the economic value of entomopathogenic microorganisms. In this study, we isolated and identified disease-causing fungi from white muscardine silkworms, and confirmed whether this strain could produce white muscardine silkworms. For the analysis of the cause of white muscardine disease in the infected silkworms, the fungi and prokaryotes causing the disease were identified, isolated, and identified using metagenome analysis. Metagenomic analysis detected a large amount of the fungus Metarhizium rileyi in silkworms, and a large amount of the bacterium Enterococcus mundtii, which was presumed to be the causative agent of the disease. For accurate identification of the fungi, these were purified by culture medium, and sequencing and phylogenetic tree analyses were performed using an internal transcribed spacer. As a result, M. rileyi, Cladosporium cladosporioides, and C. tenuissimum were identified. In general, M. rileyi is known to form green conidia, but in this study, white-yellow conidia were formed, indicating that the exact causative agent of the fungal disease cannot be estimated by diagnosing the symptoms. Thus, a diagnostic method is necessary for the continuously collection of required pathogens, and identifying their morphological and genetic characteristics.

• 한국환경보건학회지
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• 제45권3호
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• pp.222-230
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• 2019

Objectives: This study aims to evaluate water quality in terms of microorganisms and identify the antibiotic resistance of Enterococci isolated from the recycling water in floor fountains at three parks and one reservoir in the Gwangju area. Methods: Water samples were analyzed for Enterococci using membrane Enterococcus indoxyl ${\beta}$ d glucoside agar (mEI) as described in USEPA Method 1600. The vancomycin-resistant Enterococci with VanA and VanB were identified by PCR. An examination of the antibiotic resistance of isolates against 14 antibiotics was performed by the disk diffusion method. Results: The drinking water quality criterion was exceeded for total colony counts in 68% of all recycling water samples. The average concentration of total califorms and fecal coliforms was 139,325 and 413 CFU/100 mL, respectively. VanA and VanB were not detected from the isolates. We found the antibiotic resistant Enterococci strains to be E. faecalis, E. faecium, E. durans, E. mundtii, E. hirae, and E. thailandicus. The isolates were resistant to Rifampin (50%), Erythromycin (25.8%), Tetracycline (10.2%), Nitrofurantoin (8.1%), Minocycline (3.1%), Erythromycin (1.2%), Penicillin (0.7%), Norfloxacin (0.5%), and Teicoplanin (0.5%) among the 14 antibiotics tested. Antibiotic resistance tests for Enterococci from the recycling water of floor fountains resulted in 30.2% showing resistance to two or more antibiotics. Conclusions: These results showed that the multi-antibiotic resistance of Enterococci, E. coli, and others should be investigated continuously in each environment field.