• Biomolecules & Therapeutics
• /
• 제7권2호
• /
• pp.153-157
• /
• 1999

The anticancer effect of medicinal plants against two oral carcinoma cells, A253 and SCC-25 were investigated in this study. Methanol extracts from 63 medicinal plants, which have anticancer activities against other cancers such as stomach, hepatocellular or colon carcinomas, were prepared and screened for their anti- oral cancer activity by using MTT assay. Thirty one samples showed anti-oral cancer activity against either cell line used, however, other 32 samples had no anti-oral cancer activity. Among these samples methanol extract of Caesalpinia sappan revealed the strongest anti-oral cancer activity. The $IC_{50}$/ values of this extract against A253 and SCC-25 cells were 16 and 25 $\mu$g/m1, respectively. Fractions of n-hexane, dichloromethane, ethylacetate, n-buthanol and water were prepared from methanol extracts of Caesalpinia sappan, Anthriscus sylvestris, Rhus japonica, Curcuma arowatica, Inula helenium, Sinoarnudinaria reticulata, and Polygonum cuspidatum, respectively. Among these 35 fractions the n-hexane fraction of Inula helenium showed the strongest anti-oral cancer activity, the $IC_{50}$/ value was 1.6$\pm$0.3 $\mu\textrm{g}$/ml. Ten other fractions showed $IC_{50}$/ values lower than 10 $\mu\textrm{g}$/ml.

• Journal of Applied Biological Chemistry
• /
• 제61권2호
• /
• pp.187-190
• /
• 2018

Two curcumin derivatives, demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC), isolated from Curcuma longa were analyzed for their inhibitory activities against two isoforms of monoamine oxidase (MAO), which is involved in the catalysis of neurotransmitting monoamines. In the study, DMC and BDMC potently inhibited human MAO-B, with $IC_{50}$ values of 2.45 and $2.59{\mu}M$, respectively, and both compounds showed effective inhibitory activities against human MAO-A, with $IC_{50}$ values of 3.24 and $3.09{\mu}M$, respectively. The inhibitory activities of the two compounds were higher than those of curcumin. The removal of the methoxy or dimethoxy groups in curcumin might increase the inhibitory activities against human MAO-A and MAO-B. The inhibited activities were recovered to almost the values of the reversible references in the dialysis experiments with DMC and BDMC. DMC and BDMC showed competitive inhibition for MAO-A and MAO-B, respectively, with $K_i$ values of 0.91 and $0.80{\mu}M$, respectively. These results suggest that the two curcumin derivatives may be useful or lead compounds in the treatment of related disorders as potent reversible MAO inhibitors.

• 천문학회보
• /
• 제46권2호
• /
• pp.50.2-50.2
• /
• 2021

There is increasing evidence that the convective mixing length (α) in stellar evolution models depends on metallicity of stars. In order to confirm a more precise metallicity-dependent mixing length trend, we investigate the effective temperature and metallicity of 14 red supergiant stars (RSGs) in the irregular dwarf galaxy IC 1613 using the near-infrared spectra observed with the MMIRS on the MMT telescope. From the synthetic spectral fitting to the observed spectra, we find that the mean metallicity is about [Fe/H]=0.69 with a weak bimodal distribution. We also find that the effective temperature of RSGs in IC 1613 is higher by about 250 K than that of the SMC on average. We compare the RSG position with stellar evolutionary tracks on the HR diagram, finding that models with α = 2.2-2.4 H_p can best reproduce the effective temperatures of the RSGs in IC 1613. It is evident that the mixing length values for IC 1613 is lower than that of the Milky Way. This result supports our previous study on a metallicity-dependent mixing length: mixing length decreases with decreasing metallicity of host galaxies. However, this dependency becomes relatively weak for RSGs having a metallicity equal to or less than the SMC metallicity.

• 생명과학회지
• /
• 제25권7호
• /
• pp.786-794
• /
• 2015

본 연구는 황금찰수수의 에탄올 추출물을 이용하여 항산화 활성 및 뉴라니미데이즈 억제 효과를 조사하였다. 헥산, 에틸아세테이트, 메탄올과 70% 에탄올 조추출물에서 항산화력의 IC₅₀값을 비교한 결과 70% 에탄올 추출물이 DPPH 라디칼 소거능, ABTS 라디칼 소거능에서 각각 83.2±2.7, 85.6±2.4 μg/ml으로 가장 높았고, 뉴라니미데이즈 억제활성 IC₅₀값을 비교한 결과 메탄올 추출물에서 1.8±0.1 μg/ml로 나타났다. 또한 황금찰수수 추출물에서 컬럼크로마토그래피와 UPLC-PDA-MS/MS 분광기 분석을 통해, Gallic acid (1), Protocatecuic acid (2), p-Hydroxy benzoic acid (3), Vanillic acid (4), Caffeic acid (5), Ferulic acid (6), Luteolinidin (7), Apigeninidin (8), Luteolin (9), 총 9종의 폴리페놀 화합물을 확인하였다. 또한 각각의 화합물에 대한 항산화력의 IC₅₀값을 비교한 결과 Luteolinidin이 DPPH 라디칼 소거능, ABTS 라디칼 소거능에서 각각 10.9±0.5, 8.6±3.0 μM로 가장 우수 하였고, 뉴라니미데이즈 억제활성은 Luteolin이 12.9±3.8의 IC₅₀값과 비경쟁적 저해모델을 보였다. 결과적으로 황금찰수수는 높은 항산화 효과와 뉴라미니데이즈 억제활성을 보여 식품, 사료 등의 새로운 기능성소재로 다양하게 활용될 수 있음을 시사한다.

• Bulletin of the Korean Chemical Society
• /
• 제33권5호
• /
• pp.1571-1576
• /
• 2012

A diarylurea compound 1 possessing pyrrolo[3,2-$c$]pyridine nucleus was designed and synthesized with structure similarity to Sorafenib. Compound 1 was tested over 60-cancer cell line panel at a single dose concentration of 10 ${\mu}M$ and showed high activity. It was further tested in a five-dose mode to determine its $IC_{50}$, TGI, and $LC_{50}$ values over the 60 cell lines. Compound 1 showed high potency and good efficacy, and was accordingly tested at a single dose concentration of 10 ${\mu}M$ over a panel of 40 kinases. At this concentration, it completely inhibited the enzymatic activities of a number of oncogenic kinases, including ABL, ALK, c-RAF, FLT3, KDR, and TrkB. The target compound was subsequently tested over these 6 kinases in 10-dose testing mode in order to determine its $IC_{50}$ values.

• 생약학회지
• /
• 제29권4호
• /
• pp.271-276
• /
• 1998

The inhibitory effects of MeOH extracts of 100 medicinal herbs on monoamine oxidase (MAO) activity were investigated. MAO was purified from mouse brain and its activity was determined by fluorospectrophotomer using kynuramine as a substrate. Nine kinds of MeOH extracts of herbs including Artemisia iwayomogi showed a mild inhibitory effect with ${100}-{200}\;{\mu}/ml$ in their $IC_{50}$ values on MAO activity. Seventeen MeOH extracts including Juglans mandshurica exhibited a weak inhibition of MAO activity with ${200}-{300}\;{\mu}/ml$ in their $IC_{50}$ values.

• Natural Product Sciences
• /
• 제18권4호
• /
• pp.233-238
• /
• 2012

Nine compounds (1 - 9), ${\alpha}$-linolenic acid (1), cis-5,8,11,14,17-elcosapentaenoic acid (2), phytol (3), loliolide (4), uridine (5), thymidine (6), deoxyadenosine (7), adenine (8), and adenosine (9), were isolated from the n-hexane, methylene chloride, ethyl acetate and n-butanol fractions of Capsosiphon fulvescens. The structures of these compounds were elucidated on the basis of spectroscopic evidence. Compounds 1 - 9 exhibited acetylcholinesterase (AChE) inhibitory activities with $IC_{50}$ values ranging from 114.91 to $252.40{\mu}M$, whereas 2 - 4 showed butyrylcholinesterase (BChE) inhibitory activities with $IC_{50}$ values ranging from 251.18 to $499.16{\mu}M$.

• Archives of Pharmacal Research
• /
• 제25권5호
• /
• pp.625-627
• /
• 2002

From the leaves of Brassica juncea, an radical scavenging isorhamnetin 7-Ο-glucoside on peroxynitrite and 1,1-diphenyl-2-picrylhydrazyl (DPPH) was isolated and characterized based on the spectroscopic evidence. The compound showed the peroxynitrite and DPPH scavenging activities with $IC_{50}$ values of 2.07$\pm$0.17 and 13.3 $\mu$M, respectively. Penicillamine and L-ascorbic acid as positive control exhibited radical scavenging activities with $IC_{50}$ values of 3.17$\pm$0.39 and 12.78 $\mu$M, respectively.

• Journal of Advanced Marine Engineering and Technology
• /
• 제23권4호
• /
• pp.543-551
• /
• 1999

Diesel engine is a major source of the air pollution. In general the concentrations of these pollu-tants in diesel engine exhaust differ from values calculated assuming chemical equibrium. Thus the detailed chemical mechanisms by which these pollutions form and the kinetic of these process-es are important in determining emission levels. In this study the computer program has been developed to calculate the required thermodynam-ic properties of combustion products(10 spacies) for both equilibrium and non-equilibrium in cylin-der for diesel engines. Nitric oxide emissions are calculated by using the extended Zeldovich Kinet-ic mechanism with a steady state assumption for the N concentration and equilibrium values used for H, O, $O_2$ and OH concentrations. By the results it is confirmed that developed simulations program with the NO prediction model is validated against residual mass fraction combustion index of Wiebe's functions pre-mixed com-bustion ration fuel injection timing.

• 한국임상약학회지
• /
• 제8권2호
• /
• pp.139-142
• /
• 1998

The effects of MeOH extracts from 28 herbal medicines on monoamine oxidase (MAO) activity were investigated. MAO was purified from mouse brain and its activity was determined by fluoro-photometry using kynuramine as a substrate. Three MeOH extracts, Coptis japonica, Cinnamomum cassia and Poncirus trifoliate from the herbal medicines showed a strong inhibitory effect with less than $100\;{\mu}g/ml$ in their inhibitory amounts of $50\%$ ($IC_{50}$ values) on MAO activity. Four MeOH extracts including Evodia officinalis exhibited a mild inhibition of MAO activity with $100-200\;{\mu}g/ml$ in their $IC_{50}$ values.