• Title/Summary/Keyword: $C_L/C_D$

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Triterpenoid Saponins from Elsholtzia bodinieri

  • Hu, Hao-Bin;Zheng, Xu-Dong;Hu, Huai-Sheng;Jian, Yu-Feng
    • Bulletin of the Korean Chemical Society
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    • v.28 no.9
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    • pp.1519-1522
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    • 2007
  • A new oleanane-type triterpenoid estersaponin, bodinierin C (1), along with two known saponins, mazusaponin I (2) and ciwujianoside C (3), were isolated from the water-soluble part of the root barks of Elsholtzia bodinieri. The structure of bodinierin C was characterized by spectroscopic means and chemical hydrolysis as 3β -Ocaffeoyl- 23-hydroxylechinocystic acid 28-O-α -L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β- D-glucopyranosyl ester. The known compounds were identified by comparing their spectral data with those of authentic samples or data reported in the literature. All compounds were firstly isolated from Elsholtzia bodinieri family.

Isolation and Properties of Amino Acid Antimetabolite from Streptomyces sp. YS-943 (Streptomyces sp. YS-943균주가 생산하는 아미노산 대사길항물질의 정제와 성상)

  • 유성재;박부길
    • Microbiology and Biotechnology Letters
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    • v.23 no.1
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    • pp.81-86
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    • 1995
  • A Streptomyces strain YS-943, which produced amino acid antimetabolite, was isolated from soil. During the course of screening for new amino acid antimetabolites from the culture broth of Actinomycetes, we found that the strain produced a substance active against Gram-positive bacteria and its activity was reversed by L-methionine and L-histidine on the synthetic minimal agar medium in the culture broth.The morphological and cultural characteristics serve to identify the producing organism strain YS-943 as the genus Streptomyces. Fermentation was carried out in the synthetic medium at 28$\CIRC$C for 48 hours. The fermentation yield reached about 12 mg per liter of the broth. The YS-943 substance was obtained as white powder, mp 194$\CIRC$C and has the molecular formular of C$_{4}$H$_{8}$N$_{2}$O$_{4}$. Its structure was determined to be o-carbamyl-D-serine by spectroscopic data. It is active against some Gram-positive bacteria and reversed by L-methionine and L-histidine.

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Chemical Structures and Physiological Activities of Plant Growth Substance, Malformin A's (식물생장조절물질 말포민 A동족체의 화학구조 및 생리활성)

  • Kim, K.W.
    • Korean Journal of Weed Science
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    • v.15 no.1
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    • pp.73-84
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    • 1995
  • Four malformin A's produced by Aspergillus niger van Tiegh. were separated by HPLC equipped with $C_{18}$ reversed-phase column and subjected to structural determination. Amino acid analyses and mass spectra data of the compounds indicate that they structurally resemble the cyclic pentapeptide malformin $A_1$. Their structures were deduced by two dimensional NMR and MS/MS experiments as cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-Ile for $A_1$, cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-Val for $A_2$, cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-Leu for $A_3$, and cyclo-D-Cys-D-Cys-L-Val-D-Ile-L-Val for $A_4$. Among the mal-formin A's, the structure of $A_3$ was identical to that of malformin C, which was produced by A. niger strain AN-1. All the malformin A's caused severe curvatures of corn(Zea mays L.) roots and the activities of the malformin A's with molecular weight 529 were greater than those with molecular weight 515. Malformin $A_1$ caused the corn root curvature by 83% at a concentration of $0.25{\mu}M$. In the mung bean(Phaseolus aureus Roxb.) hypercotyl segment test, however, the molecular weight of malformin A's was not a factor influencing the physiological activities. Malformin $A_1$ stimulated the growth of mung bean hypercotyles by 165% at a $0.1{\mu}M$ concentration.

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Temperature-driven Models of Lipaphis erysimi (Hemiptera: Aphididae) Based on its Development and Fecundity on Cabbage in the Laboratory in Jeju, Korea (양배추에서 무테두리진딧물의 온도의존 발육 및 산자 단위모형)

  • Oh, Sung Oh;Kwon, Soon Hwa;Kim, Tae Ok;Park, Jeong Hoon;Kim, Dong-Soon
    • Korean journal of applied entomology
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    • v.55 no.2
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    • pp.119-128
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    • 2016
  • This study was conducted to develop temperature-driven models for a population model of turnip aphid, Lipaphis erysimi: nymphal development rate models and apterious adult's oviposition (larviparous) model. Nymphal development and the longevity and fecundity of adults were examined on cabbage at six constant temperatures (10, 15, 20, 25, 30, $35{\pm}1^{\circ}C$, 16L:8D). L. erysimi nymphs did not survive at $10^{\circ}C$. Development time of nymphs increased with increasing temperature up to $30^{\circ}C$ and thereafter slightly decreased, ranging from 18.5 d at $15^{\circ}C$ to 5.9 d at $30^{\circ}C$. The lower threshold temperature and thermal constant were estimated as $7.9^{\circ}C$ and 126.3 degree days, respectively. The nonlinear model of Lactin 2 fitted well for the relationship between the development rate and temperature of small (1+2 instar), large (3+4 instar) and total nymph (all instars). The Weibull function provided a good fit for the distribution of development times of each stage. Temperature affected the longevity and fecundity of L. erysimi. Adult longevity decreased as the temperature increased and ranged from 24.4 d at $20^{\circ}C$ to 16.4 d at $30.0^{\circ}C$ with abnormal longevity 18.2 d at $15^{\circ}C$, which was used to estimate adult aging rate model for the calculation of adult physiological age. L. erysimi showed a maximum fecundity of 91.6 eggs per female at $20^{\circ}C$. In this study, we provided three temperature-dependent components for an oviposition model of L. erysimi: total fecundity, age-specific cumulative oviposition rate, and age-specific survival rate.

Isolation and Characteristics of Listeria monocytogenes from Frozen Foods in Korea (국내에서 판매되는 냉동식품으로부터 Listeria monocytogenes의 분리 및 특성조사)

  • Chang, Yun-Hee
    • Korean Journal of Food Science and Technology
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    • v.31 no.5
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    • pp.1324-1329
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    • 1999
  • This study was carried out to investigate the distribution and characteristics of Listeria monocytogenes isolated from frozen Mandoo and pizza in 1998. A total 72 samples were examined and USDA, FDA and modified cold enrichment methods were used for the detection of Listeria spp. Overall prevalence of L. monocytogenes in frozen foods was 9.7% and L. monocytogenes was isolated from 11.1% of frozen Mandoo and 5.6% of frozen pizza. The highest detection rate of Listeria spp. in frozen Mandoo was found at USDA method and the serotype of L. monocytogenes isolates was 4. Isolated L. monocytogenes was confirmed by PCR method with Hly 1 and 2 as primers. It would be necessary to develop more rapid and specific method to isolate and confirm L. monocytogenes from foods because USDA and PCR methods used in this study took 3-4 days. D value of L. monocytogenes isolate in tryptic soy broth was 49.2 sec at $60^{\circ}C$ and 8.8 sec $at\;65^{\circ}C$, and D value of L. monocytogenes in foods with high distribution rate of Listeria spp. would be necessary to evaluate for the safe use of frozen foods.

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Development of Vancomycin Dosing Nomogram Based on Clinical Pharmacokinetic Data of Korean Adult Patients (한국성인환자의 임상약동학 자료를 이용한 반코마이신 용량설정표 (nomogram)의 개발)

  • 배성미;김상일;강문원;조혜경
    • YAKHAK HOEJI
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    • v.45 no.2
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    • pp.153-160
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    • 2001
  • This research developed an intravenous (IV) vancomycin dosing nomogram based on the clinical pharmacokinetic data of Korean adult patients. Total 99 pairs of steady-state peak and trough serum concentrations of vancomycin were obtained from 73 adult patients in a tertiary general hospital. Serum vancomycin concentrations were determined to assess the appropriateness of initial vancomycin dosing. Only 47.2% of the cases were within therapeutic range. To characterize the clinical pharmacokinetics (PK) of vancomycin, PK parameters including elimination rate constant ( $K_{e}$) half-life( $T_{1}$2/), clearance (C $l_{van}$), volume of distribution ( $V_{d}$) were calculated by using one-compartment, first order pharmacokinetic equations. PK parameters were evaluated based on the differences of patients'renal function and age. Regression analysis showed a significant correlation between C $l_{van}$ and $C_{cr}$ (C $l_{van}$ = -1.89+0.914 $C_{cr}$ , r=0.763) and between $K_{e}$ and $C_{cr}$ , ( $K_{e}$=-0.0037+0.00139 $C_{cr}$ =0.724). The relationship between $K_{e}$ and $C_{cr}$ , and the mean $V_{d}$ were utilized for developing the nomogram to individualize the initial dosing regimen of vancomycin for the patients with various degrees of renal functions. The nomogram may be used as an efficient tool to determine safe and effective doses of vancomycin for the Korean adult patients.nts.nts.nts.s.nts.

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Production of Indole-3-acetate in Corynebacterium glutamicum by Heterologous Expression of the Indole-3-pyruvate Pathway Genes

  • Kim, Yu-mi;Kwak, Mi-hyang;Kim, Hee-sook;Lee, Jin-ho
    • Microbiology and Biotechnology Letters
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    • v.47 no.2
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    • pp.242-249
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    • 2019
  • Biosynthesis of indole-3-acetate (IAA) from L-tryptophan via indole-3-pyruvate pathway requires three enzymes including aminotransferase, indole-3-pyruvate decarboxylase, and indole-3-acetate dehydrogenase. To establish a bio-based production of IAA, the aspC, ipdC, and iad1 from Escherichia coli, Enterobacter cloacae, and Ustilago maydis, respectively, were expressed under control of the tac, ilvC, and sod promoters in C. glutamicum. Cells harboring ipdC produced tryptophol, indicating that the ipdC product is functional in this host. Analyses of SDS-PAGE and enzyme activity revealed that genes encoding AspC and Iad1 were efficiently expressed from the sod promoter, and their enzyme activities were 5.8 and 168.5 nmol/min/mg-protein, respectively. The final resulting strain expressing aspC, ipdC, and iad1 produced 2.3 g/l and 7.3 g/l of IAA from 10 g/l L-tryptophan, respectively, in flask cultures and a 5-L bioreactor.

Effect of droplet length on a burning constant rate of suspended droplet (액적간격이 고정액적의 연소율상수에 미치는 영향에 관한 연구)

  • Han, Jae-Seob;Kim, Seon-Jin;Kim, Yoo
    • Journal of the Korean Society of Propulsion Engineers
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    • v.6 no.1
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    • pp.47-54
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    • 2002
  • This paper presents the results of an experimental investigation on the combustion of single droplets and 1-D droplet arrays of jet A-1 fuel droplets in atmospheric pressure. Experimental results indicate that burning rate constants$({\kappa}_c)$ of jet A-1 fuel droplets were independent of initial droplet size as $0.915{mm}^2$/sec. It was acquired a general relationship expressing the variation of $d^2$ with time for droplet burning For 1-D droplet arrays $(l/d_o$=1.208{\sim}2.922)$/TEX>, the burning rate constant ${\kappa}_c$ decreased with decreasing droplet spacing $l/d_o$ and, The effect on combustion rate constant ${\kappa}_c$ was stronger to second fuel droplet than third fuel droplet with uniform droplet distance

C-reactive protein and N-terminal pro-brain natriuretic peptide discrepancy: a differentiation of adenoviral pharyngoconjunctival fever from Kawasaki disease

  • Choi, Jung Eun;Kang, Hee Won;Hong, Young Mi;Sohn, Sejung
    • Clinical and Experimental Pediatrics
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    • v.61 no.1
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    • pp.12-16
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    • 2018
  • Purpose: To differentiate adenoviral pharyngoconjunctival fever (PCF) from acute Kawasaki disease (KD) using laboratory tests before results of virus-real time polymerase chain reaction and ophthalmologic examination are obtained. Methods: Baseline patient characteristics and laboratory measurements were compared between 40 patients with adenovirus infection and 123 patients with KD. Results: The patients with adenovirus infection were generally older than those with KD (median: 3.9 years vs. 2 years, P=0.000). White blood cell and, platelet count, and aspartate aminotransferase, alanine aminotransferase, and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels showed significant differences between the 2 groups, but the C-reactive protein (CRP) levels did not ($6.8{\pm}3.0mg/dL$ vs. $8.3{\pm}5.8mg/dL$, P=0.126). In the adenovirus infection group, the CRP levels were <1, <3, <10, and ${\geq}10mg/dL$ in 2 (5%), 3 (7.5%), 30 (75%), and 5 patients (12.5%), respectively. The cutoff NT-proBNP level was 265 pg/mL. Discrepancy was defined as CRP and NT-proBNP levels of ${\geq}3$ or <3 mg/dL, and <265 or ${\geq}265pg/mL$, respectively. Among the 35 patients with adenovirus infection whose CRP levels were ${\geq}3mg/dL$, 29 (82.9%) showed a discrepancy. Conversely, of the 103 patients with KD whose CRP levels were ${\geq}3mg/dL$, 83 (80.6%) showed no discrepancy. Between the groups, a significant difference in discrepancy rate was observed (P=0.000). None of the patients with adenovirus infection had CRP and NT-proBNP levels of <3 mg/dL and ${\geq}265pg/mL$, respectively. Conclusion: With a sensitivity of 82.9% and a specificity of 80.6%, CRP and NT-proBNP levels may differentiate between adenoviral PCF and acute KD.

The Influence of Temperature Pretreatment on the Production of Microspore Embryos in Anther Culture of Capsicum annuum L. (고추 (Capsicum annuum L.)의 약배양 시 온도 전처리가 소포자배 발생에 미치는 영향)

  • 김문자
    • Korean Journal of Plant Tissue Culture
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    • v.26 no.2
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    • pp.71-76
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    • 1999
  • Anthers of two hot pepper cultivars, Milyang-jare and Geryongsan-jare, were cultured on MS medium containing 0.1 mg/L 2,4-D and 0.1 mg/L kinetin. The influence of pretreatment at 4$^{\circ}C$ and 32$^{\circ}C$ on induction of microspore embryo was investigated. Milyang-jare was superior to the Geryongsan-jare in microspore embryo induction. The 32$^{\circ}C$ pretreatment increased embryo induction compared to the 4$^{\circ}C$ pretreatment while the 4$^{\circ}C$ pretreatment stimulated callus induction. Microspore embryos were regenerated to plantlets in the same medium or hormone free medium at 32$^{\circ}C$ treatment but most embryos failed to develop directly into plantlets at 4$^{\circ}C$ treatment. The optimal period of the 32$^{\circ}C$ pretreatment was 3 days in Milyang-jare and 6 days in Geryongsan-jare. The 32$^{\circ}C$ pretreatment was essential for induction and growth of microspore embryo in pepper.

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