• KSBB Journal
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• 제15권3호
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• pp.219-225
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• 2000

Bacillus thuringiensis를 생물농약으로 이용하기 위해서는 고농도의 포자형성에 의한 높은 살충성의 8 -endotoxin를 생산하는 것이 중요하다. 따라서 본 연구에서는 B. thuringiensis의 고농도 배양에 의한 높은 포자형성 수율을 얻기 위하여 40%의 용존산 소량과 $28^{\circ}C$에서 여랴 가지 방법의 유가식 배양법을 검토하였다. 최종 배양액의 glucose 농도가 50 g/L가 되도록 하는 경우의 유가식 배양에서는 continuos fed-batch culture의 linear gradient f feeding 법에 의하여 $9.37{\times}109$ cell/mL의 최대 생존 세포 수와 8 8.33 X 109 spore/mL의 최대 포자 수를 얻었으며, 이때의 포자 형 성율은 88.9% 이었다 최종 배양액의 glucose 농도가 100 m/L가 되도록 하는 경우의 유가식 배양에서는 intermittent fed-batch culture의 pH-stat 법에 의하여 $1.35{\times}1010$cell/mL의 최대 생존 세포 수와 $1.35{\times}1010$ spore/mL의 최대 포자 수를얻었으며, 이 때의 포자 형성율은 97.8% 이엇다.

• 식물조직배양학회지
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• 제27권5호
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• pp.387-393
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• 2000

The process by which Agrobacterium tumefaciens genetically transforms plants involves a complex series of reactions communicated between the pathogen and the plants. To identify plant factors involved in agrobacterium-mediated plant transformation, a large number of T-DNA inserted Arabidopsis thaliana mutant lines were investigated for susceptibility to Agrobacterium infection by using an in vitro root inoculation assay. Based on the phenotype of tumorigenesis, twelve T-DNA inserted Arabidopsis mutants(rat) that were resistant to Agrobacterium transformation were found. Three mutants, rat1, rat3, and rat4 were characterized in detail. They showed low transient GUS activity and very low stable transformation efficiency compared to the wild-type plant. The resistance phenotype of rat1 and rats resulted from decreased attachment of Agrobacterium tumefaciens to inoculated root explants. They may be deficient in plant actors that are necessary for bacterial attachment to plant cells. The disrupted genes in rat1, rat3, and rat4 mutants were coding a arabinogalactan protein, a likely cell wall protein and a cellulose synthase-like protein, respectively.

• 한국식품영양학회지
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• 제5권2호
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• pp.77-83
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• 1992

The optimum conditions and mechanisms for the plasmid-mediated genetic transformation of intact cells of Bacillus brevis Pl76-2, an extracellular protein producing bacterium by electroporation were investigated. It was found that pUB110 Plasmid DNA can be introduced into intact bacterial cells by electroporation. The frequency of transformation by this electroporation system depended upon the initial electric field strength, the capacity of the electric discharge capacitor, growth stage, number of successive pulses and composition of electroporation buffer. It was effective for transformation that cells were harvested, washed and resuspended with HSM [7M HEPES(PH 7.4), 272mM sucrose, 1 mM MgCl2] electroporation buffer when cell growth was attained to 1.2 at OD660. A maximum frequency of transformation of 2.40$\times$104 transformants per$\mu$g plasmid DNA was obtained by two succesive Pulses with an initial electric field strength of 12.5kV/cm and with a capacitance of 7.3uF.

• International Journal of Oral Biology
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• 제35권2호
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• pp.35-42
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• 2010

The use of bacteria in the treatment of cancer has a long and interesting history. The use of live bacteria in this way however has a number of potential problems including toxicity. Purified low molecular weight bacterial proteins have therefore been tested as anticancer agents to avoid such complications. Oral cancer is a widely occurring disease around the world and these lesions are typically very resistant to anticancer agents. In our present study we investigated the effects of purified recombinant azurin from Pseudomonas (P.) aeruginosa against YD-9 (p53-positive) human oral squamous carcinoma cells. Azurin showed cytotoxic effects against these cells in a dose dependent manner. The cell death accompanied by this treatment was found to be characterized by chromatin condensation and apoptotic bodies. Azurin treatment was further found to increase the expression of p53 The stabilization of p53 and induction of apoptosis in YD-9 cells by azurin suggests that it has potentially very strong anticancer properties in oral squamous carcinoma.

• Asian Pacific Journal of Cancer Prevention
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• 제17권sup3호
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• pp.279-285
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• 2016

It has been established that different kinds of bacteria agents are involved in various cancers. Although the mechanism of tumorigenesis is not clearly understood, there is evidence for the presence of bacteria within tumors, with at least a progression effect for some bacteria that prepare suitable microenvironments for tumor cell growth. The aim of current study was to evaluate bacterial dysbiosis in sentinel lymph nodes of breast cancer patients. One hundred and twenty three fresh-frozen sentinel lymph nodes and a corresponding number of normal adjacent breast tissue specimens and five normal mastectomy samples were investigated employing RT-PCR. In addition using genus-specific primers were applied. There was a significant differences as presence of Methylobacterium radiotolerance DNA recorded between patients and normal control group (p= 0.0). Based on our research work, further studies into the role of microbes in breast cancer would be of great interest.

• 대한의생명과학회지
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• 제24권4호
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• pp.292-304
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• 2018

Microbes is becoming increasingly forensic possibility as a consequence of advances in massive parallel sequencing (MPS) and bioinformatics. Human DNA typing is the best identifier, but it is not always possible to extract a full DNA profile namely its degradation and low copy number, and it may have limitations for identical twins. To overcome these unsatisfactory limitations, forensic potential for bacteria found in evidence could be used to differentiate individuals. Prokaryotic cells have a cell wall that better protects the bacterial nucleoid compared to the cell membrane of eukaryotic cells. Humans have an extremely diverse microbiome that may prove useful in determining human identity and may even be possible to link the microbes to the person responsible for them. Microbial composition within the human microbiome varies across individuals. Therefore, MPS of human microbiome could be used to identify biological samples from the different individuals, specifically for twins and other cases where standard DNA typing doses not provide satisfactory results due to degradation of human DNA. Microbial forensics is a new discipline combining forensic science and microbiology, which can not to replace current STR analysis methods used for human identification but to be complementary. Among the fields of microbial forensics, this paper will briefly describe information on the current status of microbiome research such as metagenomic code, salivary microbiome, pubic hair microbiome, microbes as indicators of body fluids, soils microbes as forensic indicator, and review microbial forensics as the feasibility of microbiome-based human identification.

• 대한임상검사과학회지
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• 제47권4호
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• pp.279-285
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• 2015

본 연구는 경기도와 인천지역의 치과 병원급 19개 기관, 의원급 28개 기관 진료실의 유닛체어 등받이, 라이트 손잡이, 타구대 표면의 검체를 채취하여 실험하였다. 우선 치과 진료실 내 표면의 세균수는 타구대 $44.82{\times}10^3CFU/mL$, 라이트 손잡이 $5.47{\times}10^3CFU/mL$ 유닛체어 $16.28{\times}10^3CFU/mL$로 타구대가 높게 측정되었으며, 의료기관의 규모로는 병원급이 높게 나타났고, 환자수가 많을수록 타구대에서 세균수가 높게 측정되었다. 표면 세균 동정 결과는 Gram positive 균주는 47.3%, Gram negative 균주는 52.7%였으며, Gram positive 균주 중 Micrococcus luteus 10.9%, Bacillus pumilus, Staphylococcus aureus 균주가 각각 3.6%로 확인되었다. Gram negative 균주로는 Acinetobacter ursingii 5.5%로 가장 많이 검출되었으며, Brevundimonas diminuta, Chryseobacterium (Flavo.) indologenes (CDC IIb), Methylobacterium sp.가 각각 4.5%로 나타났다. 이에 본 연구는 치과 진료실 내 표면 세균 오염도를 측정하고, 세균의 종류를 확인함으로써 진료실 내 감염관리의 중요성을 인식시키고, 감염방지에 대한 구체적인 계획 수립의 기초 자료가 될 것으로 사료된다.

• 한국식품과학회지
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• 제12권4호
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• pp.272-277
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• 1980

본 연구는 유용 세균의 포자를 정제화(tabletting)하는 과정에서 포자의 내구성 특히 타정 압력에 대한 세균 포자의 파괴율을 규명하려 하였다. Bacillus coagulans, Bacillus subtilis 및 Clostridium butyricum의 세가지 포자 형성균의 포자와 포자를 형성하지 않는 세균인 Streptococcus faecalis의 영양세포에 대하여 시험하였다. 정제제조 과정에서 포자의 파괴는 주로 타정과정에서 일어나며 세균의 포자는 타정압력에 대하여 대수적 파괴율을 나타내었다. 세균포자의 압력에 의한 파괴율은 세균의 종류에 따라 달라지며 이것을 정량적으로 나타내기 위하여 Decimal Reduction Pressure라는 개념을 도입하여 P-value라 칭하고 각 세균 포자의 P-value를 구하였든 바 B. subtilis의 포자는 $2.9\;ton/cm^2$, B. coagulans의 포자는 $2.6\;ton/cm^2$, Cl. butyricum의 포자는 $2.1\;ton/cm^2$의 값을 각각 나타내었다. 반면, Str. faecalis의 영양세포는 $1.7\;ton/cm^2$의 낮은 값을 나타내었다. 세균포자의 파괴율은 사용하는 부형제에 따라 영향을 받았으며 동일한 B. coagulans의 포자라도 lactose filler에서는 그 P-value가 $2.8\;ton/cm^2$이었으며 starch filler에서는 $2.0\;ton/cm^2$이었다. 동일한 부형제를 사용하였을 때 생존 포자수는 정제의 경도와 밀도에 역비례하였다. 그러나 경도와 밀도가 낮은 starch filler에서는 lactose filler에 비교하여 더 높은 포자 파괴율을 보였다. 결론적으로 부형제의 종류는 정제 형성뿐만 아니라 세균 포자의 생존에도 중요한 요인이며, 물리적 성질이 서로 다른 부형제를 알맞게 혼합함으로서 타정시 유용세균포자의 생존율을 크게 향상시킬 수 있다.

• 한국식품조리과학회지
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• 제19권4호
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• pp.521-528
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• 2003

This research was conducted to find the effects of the addition of kugija to the quality and conservativeness of Nabak kimchi. Kugija extract was prepared by boiling kugija fruits, at different ratios (1, 3, 5 and 7%; w/v) in water for 30 minutes. The changes in the sensory and microbiological properties of the Nabak kimchi were measured for 25 days, following the preparation at a uniform temperature of 10$^{\circ}C$, and compared to a control (distilled water without kugija). For the properties of acceptability, the Nabak kimchi treated with 3% kugija was evaluated as being best during the whole fermentation. The number of total cell counts and number of lactic acid microorganisms gradually increased to a maximum, and then decreased. It was the maximum for controlling and 1 % treatment on day 2, forand 3, 5 and 7% treatment on day 7. (Eds note: the highlighted sentence needs c1arification\ulcorner)This experimental study revealed the effect of kugija extract in enhancing the eating qualities on Nabak kimchi and retarding the fermentation over the initial seven days. The optimum levels of kugija extract on Nabak kimchi obtained through experiments was between 1 and 3% of the water content. Although 3% gave a better color, the fermentation-retarding effect and savory taste. The application of kugija extract could be domestically applied to improve the eating quality and the preservation of traditionally prepared Nabak kimchi.

• Preventive Nutrition and Food Science
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• 제8권1호
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• pp.24-28
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• 2003

There is evidence to suggest that cranberry juice supplements improve the health of the urinary tract by inhibiting the binding of fimbriated uropathogenic E. coli to the bladder mucosa. In patients with neurogenic bladders, urinary tract infections (UTI) are particularly common and often poorly managed by antibiotic treatment. A double-blind, randomized, placebo-controlled trial was undertaken on 29 geriatric and spinal cord injured patients with dysfunctional bladders. They received three times daily at mealtimes a 4 oz bottle of cranberry juice (Ocean Spray Cranberries, USA) or a specially prepared synthetic placebo drink. Two episodes of UTI arose in week one of cranberry intake and none thereafter, compared to four episodes of UTI in 4 placebo patients in weeks four, six and 10. Mean bacterial adhesion counts on bladder cells of the patients rose during the first month of treatment in 71 % of the placebo patients compared to only 31 % of cranberry patients (p < 0.001). The difference persisted to some extent for the second and third months. Bacterial adhesion levels correlated with culture findings (higher adhesion and higher viable counts in urine) (p < 0.001), positive leukocyte nitrite tests (136$\pm$131 bacteria per cell versus 52$\pm$86 in negative tests) (p < 0.001), and higher white blood cell counts (> 10) per high power field (126$\pm$125 versus 48$\pm$85 bacteria per cell) (p<0.001). E. coli was the most frequently isolated organism (40% samples) followed by K. pneumoniae (17%) and a number of other uropathogens. Group B Streptococci, and coagulase negative Staphylococcus were recovered from urine in 4 samples but were not associated with any red blood cell presence. The daily intake of cranberry juice, in amounts which are not detrimental to long term compliance, appeared to have a role in reducing the risk of bladder colonization and infection in a highly susceptible patient population.