• Journal of Environmental Health Sciences
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• v.2 no.1
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• pp.17-19
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• 1975

Widal Test has been performed on the patients of 1052 admitted with suspicious typhoid for 5 years (Jan. '68 Dec. '72) White blood cell count, Hematocrit and Bacterial cultures are compared with widal titer and found a slight atypical variation from the characteristic pattern of it. 1. There is frequency distribution on the age of 20-40 yrs. as far as social activity concerned. (Table 1) 2. A slight leukopenia exists on the high titer of it but no definite pattern has been found. 3. S. Typhi has been grown on the low titer of it but no growth on the high titer. 4. It ia the most important in public health view point (no definite clinical symptom, Hematological, Serological, Microbiological characteristics.)

• Journal of Microbiology and Biotechnology
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• v.5 no.3
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• pp.167-171
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• 1995

A bacterial strain C-02 using methanol as a carbon source was isolated from Gumi Industrial Estate and selected based on its rapid growth and capability of poly-$\beta$-hydroxybutyrate accumulation. Characteristics of strain C-02 showed that it belongs to the Methylococcaceae family, Type II subgroup. Strain C-02 could incorporate valerate into the PHB chain to form 3-hydroxybutyrate and 3-hydroxyvalerate (P(3HB-co-3HV)). Among various nutrient limitation tests, the nitrogen limitation test resulted in the highest content of P(3HB-co-3HV) per dry cell weight, 50$%$. Under the nitrogen limited condition, the average molecular weight of P(3HB-co-3HV) obtained was determined to be approximately $2.8\times 10^5$ daltons.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.582-586
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• 2005

In this Study, we have attempted to determine the effects of dietary fructose polymers (fructan), high molecular-weight ${\beta}-(2,6)-linked$ levan, and low-molecular-weight ${\beta}-(2,1)-linked$ inulin, on two intestinal enzymes $({\beta}-glucuronidase\;and\;{\beta}-glucosidase)$. As a preliminary experiment, when intestinal microflora were cultured in anaerobic media harboring levan or its oligosaccharides, bacterial cell growth was observed in the levanoligosaccharide-supplemented media, but not in the levan-supplemented media, indicating that levan's size is important for the utilization by intestinal bacteria of levan as an energy Source. In our animal study, the intake of a levan-rich diet was determined to significantly attenuate the activity of the harmful enzyme $({\beta}-glucuronidase$, but d id not affect the activity of ${\beta}-glucosidase$.

• Journal of Microbiology and Biotechnology
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• v.13 no.2
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• pp.309-312
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• 2003

A bacterial strain NB01, isolated from wastewater, was found to utilize nitrobenzene (NB) as the sole source of nitrogen, carbon, and energy. The strain was classified as a member of a high G+C Gram-positive group and identified as Mycobacterium chelonae based on an analysis of its 16S rRNA gene sequence. The strain grew on NB with a concomitant release of about 63% of the total available nitrogen as ammonia, suggesting a reductive degradation mechanism. The optimal pH and temperature for degradation were PH 7.0-8.0 and $30^{\circ}C$, respectively. The cell growth was retarded at NB concentrations above 1.8 mM. The degradation of NB followed Michaelis-Menten kinetics within the tolerance range, and the $K_m$ and maximum specific removal rate for NB were 0.33 mM and $11.04\;h^{-1}$, respectively.

• International Journal of Oral Biology
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• v.41 no.1
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• pp.39-43
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• 2016

Dental caries, the most common oral disease, is a multifactorial disease caused by interactions among bacteria within the dental plaque, food, and saliva, resulting in tooth destruction. Streptococcus mutans has been strongly implicated as the causative organism in dental caries and is frequently isolated from human dental plaque. Photodynamic therapy (PDT) is a technique that involves the activation of photosensitizer by light in the presence of tissue oxygen, resulting in the production of reactive radicals capable of inducing cell death. Postantibiotic effect (PAE) is defined as the duration of suppressed bacterial growth following brief exposure to an antibiotic. In this study, the in vitro PAE of PDT using erythrosine and light emitting diode on S. mutans ATCC 25175 was investigated. The PAE of PDT for 1 s irradiation and 3 s irradiation were 1.65 h and 2.1 h, respectively. The present study thus confirmed PAE of PDT using erythrosine on S. mutans.

• Microbiology and Biotechnology Letters
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• v.27 no.2
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• pp.136-144
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• 1999

Since the condition of immobilization must be optimized, it is very important to know whether and on how conditions bacterial cells retain their metabolic activity during immobilization process. A bioluminescence intensity had the maximum value when cell concentrations were between 1.0 and 1.2 measured at O.D660. The strontium alginate was used as an immobilization matrix and two independent factors for immobilization of Photobacterium phosphoreum with strontium alginate were optimized with the response surface methodology(RSM) considering degree of bioluminescence. As a result, the optimum concentration for immobilization was found to be 2.4%(w/w) for sodium alginate and 0.31M for strontium chloride, respectively. A dilution was carried out with 2.5%(w/v) NaCl solution that is an optimum environmental condition for growth of P. phosphoreum. Under the such condition of immobilization, hardness could be predicted as 4.66$\times$104N/$m^2$ and it took different time according to the volume of matrix to be immobilized completely.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2071-2078
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• 2018

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight, which results in severe economic damage to rice farms. Xoo produces biofilms for pathogenesis and survival both inside and outside the host. Biofilms, which are important virulence factors, play a key role in causing the symptoms of Xoo infection. In the present study, we investigated the nutritional conditions for biofilm formation by Xoo. Although Xoo biofilm formation may be initiated by interactions with the host, Xoo biofilm cannot mature without the support of favorable nutritional conditions. Nitrogen sources inhibited Xoo biofilm formation by overwhelming the positive effect that cell growth has on it. However, limited nutrients with low amino acid concentration supported biofilm formation by Xoo in the xylem sap rather than in the phloem sap of rice.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.269-275
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• 1988

Inhibitory effects on bacterial growth by using lysozyme and mixtures of it with other antibacterial substances (sodium hexametaphosphate and sodium pyrophosphate) were investigated against the 7 kinds of hacterial strains isolated from putrefied surumi products. The growth inhibitory concentrations of lysozyme and lysozyme + sodium hexametaphosphate + sodium pyrophosphate against the bacteria were added to kamaboko, imitation crab meat and fried surumi, then viable cell count, pH and VBN were examined during the storage at $30^{\circ}C$ for 7 days. Lysozyme showed growth inhibitions against 6 of 7 isolates and the inhibition effect of mixture of antibacterial substances was multiplied against all the isolates compare with those of its individual use. Growth inhibitory effect of the substances on the bacteria was high in order of lysozyme + sodium pyrophosphate + sodium hexametaphosphate, lysozyme + sodium hexametaphosphate, lysozyme + sodium pyrophosphate and lysozyme. The most effective inhibitory concentration of mixture of the antibacterial substances in kamaboko and imitation crab meat was $0.05\%$ of lysozyme, $0.5\%$ of sodium pyrophosphate and $0.1\%$ sodium hexametaphosphate. But the bacterial growth was slightly inhibited in fried surumi even if the same concentration of the dipped mixture and the effect of the mixture was less than that of $0.2\%$ sorbic acid.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.973-978
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• 2001

The bacterial flagellar motor is a molecular machine that couples proton or sodium influx to force generation, mostly for driving rotation of the helical flagellar filament. In this study, we cloned a gene (motX) encoding a component of the sodium-driven flagellar motor from Vibrio fluvialis. The nucleotide sequence of the motX gene, composed of 633 bp and 211 amino acid residues, was determined. Overexpression of the motX gene in Escherichia coli using a strong promoter induced growth inhibition and cell lysis. The lethal effect of E. coli was suppressed by adding amiloride, as a potent inhibitor for the sodium channel. Electron microscopic observation of the expressed protein indicated that MotX protein induced by isopropyl ${\beta}$-D-thiogalactopyranoside caused the lysis of host cell.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.667-671
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• 2016

Oridonin, an ent-kaurane diterpenoid compound isolated from the traditional Chinese herb Rabdosia rubescens, has shown various pharmacological and physiological effects such as anti-tumor, anti-bacterial, and anti-inflammatory properties. However, the effect of oridonin on human ovarian cancer cell lines has not been determined. In this study, we demonstrated that oridonin inhibited ovarian cancer cell proliferation, migration and invasion in a dose-dependent manner. Furthermore, we showed oridonin inhibited tumor growth of ovarian cancer cells (SKOV3) in vivo. We then assessed mechanisms and found that oridonin specifically abrogated the phosphorylation/activation of mTOR signaling. In summary, our results indicate that oridonin is a potential inhibitor of ovarian cancer by blocking the mTOR signaling pathway.