• YAKHAK HOEJI
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• v.42 no.2
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• pp.175-180
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• 1998

Bifidobacterium bifidum OFR9 that exhibits acquired resistance to rifampicin and fluoroquinolones was selected by MNNG and multi-step mutation method. To investigate the resistance mechanism to rifampicin in the strain, RNA polymerase from B. bifidum parent strain and rifampicin-resistance OFR9 was partially purified and its sensitivity to rifampicin was assayed. The profile of RNA polymerase preparation of B. bifidum parent and B. bifidum OFR9 is similar to that of E. coli RNA polymerase that includes the basic subunits of ${\beta}$`, ${\beta},\;{\sigma},\;{\alpha}$ but which are a little different in size when they are compared with E. coli RNA polymerase subunits. RNA polymerase isolated from the parent strain was inhibited by 1${\mu}$g/ml rifampicin but that from B. bifidum OFR9 was not affected by 100${\mu}$g/ml concentration of rifampicin. RNA polymerase activity of B. bifidum OFR9 was maintained over 90% through that rifampicin concentration. This result is consistent with MIC values of in vitro test. It can be concluded that the mechanism of rifampicin resistance in B. bifidum OFR9 is due to an alteration of RNA polymerase.

• YAKHAK HOEJI
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• v.37 no.5
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• pp.483-489
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• 1993

Bifidobacterium bifidum, one strain of medical preparations being on the market for human intestinal disorder, is very sensitive to rifampicin. If this preparation is taken with rifampicin, its therapeutic effect can't be expected. To develope rifampicin resistant mutants, B. bifidum was treated with N-methyl-N'-nitro-N-nitrosoguanidine(MNNG). All of thirty strains grown on the plates containing 10 $\mu\textrm{g}$/ml rifampicin were over 1, 000 times more resistant to rifampicin than parental strain and they were identified as B. bifidum by fructose-6-phosphoate phosphoketolase test. Three strains out of thirty, which produced almost same amount of organic acid as parental strain, were selected for further studies. They showed identical growth inhibition activity aganist E. coli compared with that of parental strain. And rifampicin was not inactivated.

• Microbiology and Biotechnology Letters
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• v.51 no.4
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• pp.566-568
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• 2023

In this report, we present the whole-genome sequence of Bifidobacterium bifidum DS0908 isolated from the human fecal sample. The genome composed of a single circular chromosome is 2,223,317 bp long and the DNA G+C content is 62.65%. No virulence genes were detected in the genomic sequences of B. bifidum DS0908.

• YAKHAK HOEJI
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• v.38 no.6
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• pp.763-769
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• 1994

Bifidobacterium bifidum, one strain of medical preparation being on the market for human intestinal disorders, was sensitive to rifampicin and fluoroquinolones. If this preparation is taken with rifampicin and fluoroquinolones, its therapeutic effect can't be expected. Serial passage of B. bifidum RFR61, which was obtained by MNNG mutation method, on agar with 2-fold minimal inhibitory concentration of ofloxacin produced B. bifidum OFR9 with minimal inhibitory contentrations of fluoroquinolones up to $4{\sim}256-fold$ higher than that for the original strain. B. bifidum OFR9 produced almost the same amount of organic acid as parental strain. This strain showed growth inhibitory activity against E. coli NM522, Shigella dysenteriae ATCC9752 and E. coli 078. No inactivations of rifampicin and ofloxacin by this resistant mutant strain were found.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.749-754
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• 2009

The polysaccharide (BB-pol) extracted from Bifidobacterium bifidum BGN4 showed growth inhibitory effects on several colon cancer cell lines such as HT-29 and HCT-116. To increase the yield of polysaccharide, B. bifidum BGN4 was cultured in various culture media with different compositions. When B. bifidum BGN4 was cultured in modified MRS broth containing phytic acid, the cells showed increased branch formation and enlarged morphology. The content of total carbohydrate and the ability of adhesion to intestinal epithelial cells were also increased by phytic acid. The polysaccharide obtained from the cells grown in the presence of phytic acid inhibited the proliferation of cancer cell lines such as HT-29 and MCF-7 cells but not normal colon cell line, FHC. Taken together, Bifidobacterium grown in the presence of phytic acid may confer enhanced beneficial function for the host.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.184-187
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• 2008

S-Adenosyl-L-methionine (SAM) is an important metabolic intermediate in living organisms and participates in many reactions as a methyl group donor. SAM has been used as a dietary supplement and is proposed to have beneficial effects on the liver and brain. The aim of this study was to find lactic acid bacteria with high SAM-producing ability to be used as SAM enhancing probiotics. We used high performance liquid chromatography (HPLC) to quantify the amount of SAM produced, and found that Bifidobacterium bifidum BGN4 produced a significantly higher amount of SAM than other Bifidobacterium or Lactobacillus strains. The effect of various carbon and nitrogen sources on SAM production was examined. This study confirmed that Bifidobacterium may be utilized as a source of SAM in the functional food industry.

• Journal of Microbiology and Biotechnology
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• v.27 no.5
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• pp.909-915
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• 2017

Bifidobacterium bifidum BGN4 (BGN4) has many proven beneficial effects, including antiallergy and anticancer properties. It has been commercialized and used in several probiotic products, and thus strain-specific identification of this strain is very valuable for further strain-dependent physiological study. For this purpose, we developed novel multiplex polymerase chain reaction (PCR) primer sets for strain-specific detection of BGN4 in commercial products and fecal samples of animal models. The primer set was tested on seven strains of B. bifidum and 75 strains of the other Bifidobacterium species. The BGN4-specific regions were derived using megaBLAST against genome sequences of various B. bifidum databases and four sets of primers were designed. As a result, only BGN4 produced four PCR products simultaneously whereas the other strains did not. The PCR detection limit using BGN4-specific primer sets was $2.8{\times}10^1CFU/ml$ of BGN4. Those primer sets also detected and identified BGN4 in the probiotic products containing BNG4 and fecal samples from a BGN4-fed animal model with high specificity. Our results indicate that the PCR assay from this study is an efficient tool for the simple, rapid, and reliable identification of BGN4, for which probiotic strains are known.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.143-143
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• 1993

현재 시판되고 있는 정장용 생균 제제에 함유되어있는 정장 균주의 하나인 Bifidobacterium bifidum은 항결핵제 중 rifampicin에 감수성으로 rifampicin과 병용 투여시 본래의 정장 효과를 기대할 수없다. 따라서, rifampicin에 내성인 돌연변이 균주를 얻기 위해 B. bifidum을 N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)로 처리하여 rifampicin에 내성인 30 종의 균주를 선별하였고, rifampicin에 대한 Minimal Inhibitory Concentration (MIC)를 측정해 본 결과 내성이 1,000 배 이상 상승하였다. 균주 동정을 위하여 fructose-6-phosphate phosphoketolase test를 실시해 본 결과 Bifidobacterium임이 확인되었다. 이들 내성 균주들의 유기산 생산량을 측정하여 그 생산량이 모균주와 가장 유사한 3 종의 균주를 선발하였다. 이들에 대하여 Escherichia coli 생육 억제능을 시험해 본 결과 E. coil 생육 억제능이 모균주와 유사하였다. 또, rifampicin을 함유한 배지에서 돌연변이 균주를 배양시킨 경우 rifampicin이 안정한 상태로 잔존한 것을 알 수 있었다. 이것으로 보아 돌연변이 균주들은 rifampicin을 분해 또는 변형시키는 효소를 생산하지 않는다고 볼 수 있다. 이상의 결과로 본 연구에서 개발한 돌연변이 균주들, 즉 B. bifidum RFRll, RFR21 그리고 RFR61은 rifampicin에 내성이면서 모균주와 동일한 생화학적 특성을 갖는 정장 균주로 여겨진다.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.790-794
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• 2004

Bifidobacterium spp. exhibits the highest number of counts among species of microflora in breast-feeding infant intestines and has been used as probiotics. From infant groups with different diets, 42 Bifidobacterial strains were isolated by selective plate, Gram-staining, and morphology using method of Mitsuoka, among which seven isolates were identified as Bifidobacterium spp. by F6PPK test, MIDI, and PCR. B. bifidum PBH-30, selected for development of probiotics, showed high resistance against low pH and oxgall treatment, and inhibition against pathogens such as Salmonella typhimurium and Staphylococcus aureus. B. bifidum PBH-30 could be applicable to dairy products as probiotic strains due to its excellent growth in raw milk.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.484-489
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• 2004

Bifidobacterium species isolated from infant feces were fractionated into cell wall, cytosol, and extracellular preparations of culture broth, and each fraction was examined for Peyer's patch-mediated bone marrow cell proliferation activity in vitro. Cell wall preparation of B. bifidum SL-21 (CWP) showed the highest bone marrow cell proliferating activity dose dependently, and enhanced production of cytokines, such as hematopoietic growth factor (GM-CSF), IL-2, and IL-6, in culture supernatant of Peyer's patch cells, After treatment with lysozyme, CWP was fractionated, among which intermediate molecular-weight fraction (30-50 kDa) showed significantly high bone marrow cell proliferating activity. These results suggest CWP of B. bifidum SL-21 effectively activates lymphocytes in Peyer's patch, and several cytokines, possibly playing important role in enhancement of systemic immune system, were produced by activated lymphocytes.