• Journal of Microbiology and Biotechnology
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• 제18권7호
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• pp.1221-1226
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• 2008

The soft rot bacterium Pectobacterium wasabiae is an economically important pathogen of many crops. A new phytase gene, appA, was cloned from P. wasabiae by degenerate PCR and TAIL-PCR. The open reading frame of appA consisted of 1,302 bp encoding 433 amino acid residues, including 27 residues of a putative signal peptide. The mature protein had a molecular mass of 45 kDa and a theoretical pI of 5.5. The amino acid sequence contained the conserved active site residues RHGXRXP and HDTN of typical histidine acid phosphatases, and showed the highest identity of 48.5% to PhyM from Pseudomonas syringae. The gene fragment encoding the mature phytase was expressed in Escherichia coli BL21 (DE3), and the purified recombinant phytase had a specific activity of 1,072$\pm$47 U/mg for phytate substrate. The optimum pH and temperature for the purified phytase were pH 5.0 and 50$^{\circ}C$, respectively. The $K_m$ value was 0.17 mM, with a $V_{max}$ of 1,714 $\mu$mol/min/mg. This is the first report of the identification and isolation of phytase from Pectobacterium.

• 한국자기공명학회논문지
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• 제23권4호
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• pp.87-92
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• 2019

Allium hookeri (Liliaceae) has been received the increasing attention as a bioactive resource due to its potent biological activities including anti-oxidant, anti-obesity, anti-microbial and lipid-regulating activities. The beneficial effects of A. hookeri are known contributed from the high content of organosulfur compounds in A. hookeri. Though a variety of articles demonstrated that A. hookeri contains 'saponin' as a bioactive constituent, the scientific evidence to prove it was limited. In the present study, we have attempted to identify saponin contained in A. hookeri through chromatographic isolation and NMR spectroscopic methods. As a result, a spirostane-type steroidal saponin (1) has been successfully isolated from the methanolic extract of A. hookeri roots. The structure of 1 was elucidated by extensive 1D and 2D spectroscopic methods including ¹H-NMR, ¹³C-NMR, ¹H-¹H COSY, HSQC, HMBC and NOESY; identified as (3β, 22R, 25S)-spirost-5-en-3yl O-6-deoxy-α-L-mannopyranosyl-(1→4)-O-6-deoxy-α-L-mannopyranosyl-(1→4)-O-[6-deoxy-α-L-mannopyranosyl-(1→2)]-β-D-gluco pyranoside. 1 showed the significant inhibitory activity on mushroom tyrosinase with IC₅₀ values of 248.7 μM while the inhibition on alpha-glucosidase was not significant.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1269-1270
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• 2007

Carbon nanotubes (CNTs) are directly grown on W-tips at $700^{\circ}C$ using an ICP-CVD method. Sharpening of W-tip is done by electrochemical etch and their diameters are limited to range from $3{\mu}m$ to $5{\mu}m$. Catalysts for CNTs growth are formed by RF and DC co-sputtering systems using Ni and Co. The composition ratio of Ni and Co has been evaluated by energy dispersive x-ray spectroscopy (EDS). The micro-images of CNTs are monitored by field emission scanning electron microscope (FESEM). It is observed from Raman study that the intensity of the D-peak is increased by increasing the amount of Co catalyst. Furthermore, the measurement of field emission properties of CNTs show that the CNT grown on a single Co catalyst possess the greatest performance such as $V_{th}$=1,115V and $I_{max}=164{\mu}A$.

• Natural Product Sciences
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• 제13권2호
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• pp.123-127
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• 2007

We investigated effect of small black soybean fraction (SBSF) T cell-mediated responses for tumor surveillance and proliferation in leukemia cells in vitro. Each SBSF butanol fraction (SBSFBu) and SBSF chloroform fraction (SBSFCh) was administered p.o. once a day far 21 days in BALB/c mice and then levels of serum cytokines and subpopulation of lymphocytes were measured. Moreover, SBSF fraction was treated into the cultured various cell lines for proliferation in leukemia cell lines, NO production by RAW264.7 cells, and expression of p53 gene in U937 leukemia cells. These results showed that SBSFBu increased levels of serum IL-4but not IL-2 and IFN-${\gamma}$, and increased expression of CD4$^+$ T cells and CD8$^+$ T cells in splenocytes in vivo, while SBSFCh increased levels of serum IL-2 and IFN-${\gamma}$ but decreased IL-4, and increased CD8$^+$ T cells but not CD4$^+$ T cells. Moreover, both of SBSFBu and SBSFCh inhibited proliferation of HL60, U937, and L1210 leukemia cell lines in a dose-dependent manner, up-regulated NO production by RAW264.7 cells in a dose-dependent manner, and enhanced expression of p53 gene in U937 leukemia cells. Our findings indicate that SBSFBu and SBSFCh may enhance T cell-dependent immune responses, and that both of SBSFBu and SBSFCh may inhibit proliferation of leukemia cells by up-regulation of NO production and expression of p53 gene.

• Journal of Microbiology
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• 제35권3호
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• pp.200-205
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• 1997

Bothl $Ca^{2+}$ and Sr$^{2+}$-containing methanol dehydrogenases (MDH) were purified to homogeneity with yields of 48% and 42%, respectively, from Methylabacillus methanolovorus sp. strain SK5. Most of the biochemical and structural properties were similar to each other. However, some differences were found: (1) although the overall shape of the absorption spectrum of Sr$^{2+}$-MDH was very similar to that of $Ca^{2+}$-MDH, the absorption intensity originating from the cofactor in Sr$^{2+}$. MDH was higher than that in $Ca^{2+}$-MDH. Small blue shift of the maximum was also observed. These are probably due to a difference in redox state of the cofactors in $Ca^{2+}$ and Sr$^{2+}$-MDH; (2) Sr$^{2+}$-MDH was more heat-stable than $Ca^{2+}$-MDH above 56$^{\circ}C$; (3) the V$_{max}$ values for the methanol-dependent activities of Sr$^{2+}$- and $Ca^{2+}$-MDH in the presence of 3 mM KCN were 2.038 and 808 nmol/mg protein/min, respectively. In addition, the $K_{m}$ values of Sr$^{2+}$ and $Ca^{2+}$ MDH for methanol were 12 and 21 $\mu$M, respectively; (4) the endogenous activity of $Ca^{2+}$-MDH was more sensitive than that of Sr$^{2+}$-MDH in the presence of cyanide; (5) Diethyl pyrocarbonate treatment increased the enzyme activities of $Ca^{2+}$- and Sr$^{2+}$-MDH 4.2- and 1.4-folds, respectively. These results indicate that Sr$^{2+}$ stabilizes the structural conformation and enhances the activity of MDH more than $Ca^{2+}$.

• Biomolecules & Therapeutics
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• 제19권4호
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• pp.498-503
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• 2011

The purpose of this study was to investigate the effects of nisoldipine on the pharmacokinetics of repaglinide in rats. The effect of nisoldipine on cytochrome P450 (CYP) 3A4 activity and P-glycoprotein (P-gp) were evaluated. The pharmacokinetic parameters of repaglinide were also determined in rats after oral (0.5 $mg{\cdot}kg^{-1}$) and intravenous (0.2 $mg{\cdot}kg^{-1}$) administration of repaglinide to rats without or with nisoldipine (0.3 and 1.0 $mg{\cdot}kg^{-1}$). Nisoldipine inhibited CYP3A4 enzyme activity with a 50% inhibition concentration of 5.5 ${\mu}M$. In addition, nisoldipine significantly enhanced the cellular accumulation of rhodamine-123 in MCF-7/ADR cells overexpressing P-gp. Compared to the oral control group, nisoldipine significantly increased the $AUC_{0-{\infty}}$ and the $C_{max}$ of repaglinide by 46.9% and 24.9%, respectively. Nisoldipine also increased the absolute bioavailability (A.B.) of repaglinide by 47.0% compared to the oral control group. Moreover, the relative bioavailability (R.B.) of repaglinide was 1.16- to 1.47-fold greater than that of the control group. Nisoldipine enhanced the oral bioavailability of repaglinide, which may be attributable to the inhibition of the CYP3A4-mediated metabolism in the small intestine and/or in the liver and to inhibition of P-gp in the small intestine rather than to reduction of renal elimination of repaglinide by nisoldipine. The increase in the oral bioavailability of repaglinide should be taken into consideration of potential drug interactions when co-administering repaglinide and nisoldipine.

• Biomolecules & Therapeutics
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• 제19권4호
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• pp.493-497
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• 2011

The aim of this study was to investigate the effect of amlodipine on the pharmacokinetics of warfarin after oral and intravenous administration of warfarin in rats. Warfarin was administered orally (0.2 mg/kg) or intravenously (0.05 mg/kg) without or with oral administration of amlodipine (0.1 or 0.4 mg/kg) in rats. The effect of amlodipine on the P-glycoprotein (P-gp) as well as cytochrome P450 (CYP) 3A4 activity was also evaluated. Amlodipine inhibited CYP3A4 enzyme activity with 50% inhibition concentration ($IC_{50}$) of 9.1 ${\mu}M$. Compared to those animals in the oral control group (warfarin without amlodipine), the area under the plasma concentration-time curve (AUC) of warfarin was significantly greater (0.1 mg/kg, p<0.05; 0.4 mg/kg, p<0.01) by 26.5-53.5%, and the peak plasma concentration ($C_{max}$) was significantly higher (0.4 mg/kg, p<0.05) by 26.2% after oral administration of warfarin with amlodipine, respectively. Consequently, the relative bioavailability of warfarin increased by 1.26- to 1.53-fold and the absolute bioavailability of warfarin with amlodipine was significantly greater by 61.7-72.5% compared to that in the control group (47.4%). In contrast, amlodipine had no effect on any pharmacokinetic parameters of warfarin given intravenously. Therefore, the enhanced oral bioavailability of warfarin may be due to inhibition of CYP 3A4-mediated metabolism in the intestine and/or liver rather than renal elimination and P-gp by amlodipine.

• Biomolecules & Therapeutics
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• 제17권2호
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• pp.205-210
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• 2009

The present study investigated the effects of hydrocortisone on the pharmacokinetics of loratadine in rats after intravenous and oral administration. A single dose of loratadine was administered either orally (4 mg/kg) or intravenously (1 mg/kg) with or without oral hydrocortisone (0.3 or 1.0 mg/kg). Compared to the control group (without hydrocortisone), after oral administration of loratadine, the area under the plasma concentration-time curve (AUC) was significantly increased by 30.2-81.7% in the presence of hydrocortisone (p<0.05). The peak plasma concentration ($C_{max}$) was significantly increased by 68.4% in the presence of 1.0 mg/kg hydrocortisone after oral administration of loratadine (p<0.05). Hydrocortisone (1.0 mg/kg) significantly increased the terminal plasma half-life ($t_{1/2}$) of loratadine by 20.8% (p<0.05). Consequently, the relative bioavailability of loratadine was increased by 1.30- to 1.82-fold. In contrast, oral hydrocortisone had no effects on any pharmacokinetic parameters of loratadine given intravenously. This suggests that hydrocortisone may improve the oral bioavailability of loratadine by reducing first-pass metabolism of loratadine, most likely mediated by P-gp and/or CYP3A4 in the intestine and/or liver. In conclusion, hydrocortisone significantly enhanced the bioavailability of orally administered loratadine in rats, which may have been due to inhibition of both CYP 3A4-mediated metabolism and P-gp in the intestine and/or liver by the presence of hydrocortisone.

• 수산해양기술연구
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• 제12권1호
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• pp.25-30
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• 1976

겨울철 북서태평양인 캄차카 부근 해역에 영향을 주는 저기압의 특성을 종합,분석하고 그 발달기구를 규명하기 위하여 기상월보(1966~1974년) 9닌분과 일본 기상철 발행의 인쇄기일도(1970~1974년)5년분을 사용 분석한 결과를 요약하면 다음과 같다. 1) 겨울철 우리나라 부근에서 발현하는 저기압의 총수는 157개 였다. 이것을 월별로 보면 12월 1월에 각각 48개였고,2월에는 61개 발생했으며 경로별로는 BD경로, 즉 중국에서 발생하여 한국을 통과한 뒤 일본의 북해도로 진입하는 저기압은 총 53개로 전체의 36%로 가장 많았으며, CD경로 즉 대만 부근에서 발생하여 동해를 통과하는 저기압은 총 15개로 전체의 13%로 가장 적었다. 2)저기압 강하도는 A경로 일때가 제일 적었고, CD경로 일때가 가장 컸다. 또한 풍속변화량은 C,CD경로일 대가 최대였고, A경로 일때가 최소였다. 3)저기압이 통과하는 상층에 Jet류가 전일에 비해서 하강, 남하할 경우에는 한기중의 막대한 양이 저기압 후면으로 강하하면, 이에 따르는 위치 에너지의 감량이 저기압을 발달시킨다. 반면에 Jet류가 본래의 상태로 정체하고 있는 경우에는 위치에너지의 변화가 거의 없으므로 저기압은 별로 발달하지 않으며,만일 발달한다고 해도 해면 증발등과 같은 지상조건에 따를 뿐이다. 4)700mb면 등온선의 상층골과 기온극대축(혹은 극소축)의 상관위치 관걔는 저기압 발달에 많은 영향을 준다.

• 한국식품조리과학회지
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• 제29권1호
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• pp.19-28
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• 2013

This study was carried out to investigate the quality characteristics and storage of noodle with added flowering cherry fruit powder. Wet noodles were prepared at concentration of 1, 2, and 3% (w/w) of the fruit based on flour weight. Moisture content of the noodles with or without flowering cherry fruit powder was 33.09~33.50%. Ca, K and Mg contents of flowering cherry fruit noodle were increasing at increasing concentrations of flowering cherry fruit powder. Cooked weight, volume, and water absorption decreased with increased fruit powder, whereas turbidity increased. For Hunter's color values of noodles, L (lightness) and b (yellowness) values decreased with increasing concentration of flowering cherry fruit powder, whereas a (redness) value increased. For mechanical characteristics of the noodles, adhesiveness of cooked noodle with flowering cherry fruit powder were higher than those of control. The pH of flowering cherry fruit noodle was lower than that of control during storage. Bacterial counts of wet noodle with flowering cherry fruit powders were lower than those of the control on the 10th day of storage at $5^{\circ}C$. From the sensory evaluation of 20's, texture, taste, and overall preference were not significantly different between the control and the fruit groups, but the color scores of 2% and 3% flowering cherry fruit noodle were significantly higher than that of 1% fruit noodle (p<0.05). In 40's sensory evaluation, color and overall preference scores of flowering cherry fruit noodle were significantly higher than those of control. In conclusion, the results of this study were suggested that the addition of flowering cherry fruit powder in combination with flour was tended to improve antimicrobial effects during storage when compared to control.