• 생약학회지
• /
• 제4권4호
• /
• pp.167-172
• /
• 1973

Five crystalline substances, which are positive to$L_{IEBERMAN}-B_{URCHARD}$ reaction, were isolated from the unsaponifiable fraction of the fresh leaves of Betula latifolia $K_{OMAROV}$ (Betulaceae)by silica gel column chromatographic purification. Compound $A\;(C_{29}H_{50}O,\;mp\;136^{\circ}), \;B\;(C_{30}H_{52}O_3,\;mp\;165^{\circ}), \;C\;(C_{30}H_{52}O_4,\;mp\;237^{\circ}), \;D\;(C_{30}H_{52}O_3,\;mp\;196^{\circ})\;and\; E\;(C_{30}H_{52}O_4,\;mp\;121^{\circ})$ were isolated. Compound B was characterized as a new tetracyclic triterpenoid. Compounds A, C and D were identified as ${\beta}-sitosterol$, betulatriterpene C, and betulafolienetriol, respectively.

• 생약학회지
• /
• 제20권2호
• /
• pp.83-87
• /
• 1989

The alkaloids of thirty five Korean plants which belong to Rhamnaceae, Sterculiaceae, Celastracea, Urticaceae and Rubiaceae were screened. Plant was extracted and solvent fractionated to yield ether soluble alkaloidal fraction and butanol soluble fraction. Each fraction was subjected to alkaloidal test by Dragendorff's reaction. The result showed eighteen plants strong positive, fourteen weak and six negative to alkaloidal test.

• Bulletin of the Korean Chemical Society
• /
• 제32권10호
• /
• pp.3641-3643
• /
• 2011

Multiconfigurational wavefunctions were adopted to study structural isomers, their isomerization reactions and excited states of $HN_3$. In addition to the known linear isomer, two new structural isomers were found. The three isomers can be classified as sp, $sp^2$ and $sp^3$ hybridized species, respectively. The sp3 hybridized species turned out to be the second most stable. Large reaction barriers among these species prevent thermal isomerizations. A low-lying $^3A'$ exists with a relative energy of 13.5 kcal/mol. Dramatic re-hybridization and bond elongation was found in the first excited $^1A"$.

• Journal of Species Research
• /
• 제6권3호
• /
• pp.214-223
• /
• 2017

As part of a larger study with the aim to discover indigenous prokaryotic species in Korea, nine bacterial strains were isolated and assigned to the phylum Proteobacteria in 2016. High 16S rRNA gene sequence similarity (>98.5%) and formation of a robust phylogenetic clades with known species indicated that each strain belongs to an independent and predefined bacterial species. This is the first report of these nine species in Korea: two strains of the Methylobacterium, two strains of the Microvirga, one strain of the Pantoea, and four strains of the Psychrobacter, all within the Proteobacteria. Gram reaction, colony and cell morphology, basic biochemical characteristics, and isolation sources are also described in the species description section.

• 약학회지
• /
• 제39권1호
• /
• pp.14-23
• /
• 1995

The current study was undertaken to select the crude drug showing life prolonging effect on the starved rats(Sprague-Dawley) and elucidate the reaction mechanism there of. As distilled water extracts prepared from twenty kinds of natural drugs were administered orally to female starved rats, Bupleuri Radix demonstrated the most prominent effect with 34.6% increment in the survival time. To investigate underlying mechanism of life prolonging effect of Bupleuri Radix, the concentrations of adrenocorticosteroids(corticsterone, testosterone and aldosterone) and enzyme activities of superoxide dismutase(SOD), glutamate oxaloacetate transaminase(GOT), glutamate pyrurate transaminase(GPT) were assayed in the serums of rats starved for, 2, 4 and 6 days respectively. The results manifested much elevated values of corticosterone, aldosterone(2 days) and rather decreasing tendency afterwards, specially in the late periods of starvation(6 days). With respect to such a considerable changes according to starvation periods, Bupleur Radix restored these values much near to normal suggesting that Buplerum Radix may play a life prolonging action during starvation probably through reinforcing the homeostatic properties of corticosteroids and some enzyme activities.

• 한국균학회지
• /
• 제17권4호
• /
• pp.202-208
• /
• 1989

N-methylmaleimide와 Harmaline의 혼합용액에서 자외선을 조사시켜 합성한 주생성물을 분광학적으로 분석하였다. 그 결과 harmaline의 아민기와 N-methylmaleimide의 탄소-탄소 이중결합 사이에 광부가 반응을 한 harmaline의 N-methylmaleimide 유도체가 얻어졌으며 이 유도체는 몇 가지의 효모 및 광합성 세균의 성장을 억제하므로 생물학적 독성을 가지고 있는 것으로 보여진다.

• 콘크리트학회논문집
• /
• 제11권3호
• /
• pp.101-111
• /
• 1999

Compared with the BF slag, the EAF slag has expansion due to the reaction with water and free CaO. Therefore it is specified in Concrete Specification that the FAP slag aggregated must not be used in concrete. Because of this reason it is unusual to use the EAF slag aggregate in concrete. The EAF slag aggregate treated with accelerated and water aging was comparatively satisfied with fundamental properties, which are specific gravity, unit weight, abrasion and immersion expansion ratio, as concrete aggregate. Therefore when we measured the compressive strength till 28 days, we found that the mortar and concrete replacing the natural aggregate with the EAF slag aggregate by 4 steps had better results than the concrete using the natural aggregate in a view of the compressive strength. But at 91 days, concrete using the EAF slag aggregate had no difference with it using the natural aggregate.

• The Plant Pathology Journal
• /
• 제31권4호
• /
• pp.438-440
• /
• 2015

We developed a loop-mediated isothermal amplification (LAMP) method to rapidly diagnose Wheat streak mosaic virus (WSMV) during quarantine inspections of imported wheat, corn, oats, and millet. The LAMP method was developed as a plant quarantine inspection method for the first time, and its simplicity, quickness, specificity and sensitivity were verified compared to current reverse transcription-polymerase chain reaction (RT-PCR) and nested PCR quarantine methods. We were able to quickly screen for WSMV at quarantine sites with many test samples; thus, this method is expected to contribute to plant quarantine inspections.

• Bulletin of the Korean Chemical Society
• /
• 제6권2호
• /
• pp.86-90
• /
• 1985

(Z)-13-Eicosen-10-one, an active component of the sex pheromone of the peach fruit moth was synthesized from 4-oxo-tridecan-1-al and heptylidenetriphenylphosphonium ylide by Wittig reaction. The key intermediate, 4-oxo-tridecan-1-al, was synthesized by three different methods. The biological activity test of the synthetic pheromone as attractant for the male peach fruit moth was tested at several districts in Korea.

• Bulletin of the Korean Chemical Society
• /
• 제6권5호
• /
• pp.270-272
• /
• 1985

The rate constants of the hydrogen-deuterium exchange of 8-CH groups in 5'-rAMP and 5'-GMP were measured by laser Raman spectroscopy. The Arrhenius activation energies calculated from the rate constants measured as a function of temperature were similar for both compounds. However, the effects of pD on exchange rate constants were different for the two compounds. Our kinetic data support the exchange reaction mechanism involving an ylide type intermediate.