• Korean Journal of Medicinal Crop Science
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• v.19 no.6
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• pp.491-500
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• 2011

Ursolic acid, triterpenoid compound has been shown to stimulate osteoblast differentiation and enhance bone formation. In the present study, we examined the effects of similar triterpenoid compounds, oleanolic acid (OA) and its derivatives, such as oleanolic acid acetate (OAA) and oleanolic acetate methyl ester (OAM) on the bone formation in MC3T3-E1 osteoblast cells. We determined cellular proliferation, alkaline phosphatase (ALP) activity, mineralization, and expression of osteoblast specific genes and mitogen activated protein kinase phosphorylation. Treatment of $0.1-10{\mu}m$ OA, OAA, and OAM increased cellular proliferation, but not significantly increased as compared with dimethyl sulfoxide (DMSO). OA, OAA, and OAM at 5uM concentration enhanced ALP expression, mineralization, and osteocalcin (OCN) mRNA level. In conclusion, OA and its derivatives stimulated the osteoblast differentiation by increasing ALP, mineralization, and OCN mRNA expression. However, there were no significantly difference on osteoblast differentiation among treatment of OA, OAA, and OAM.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.9
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• pp.1204-1210
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• 2011

Objective of this study was to examine the effect of sodium nitroprusside (SNP), a nitric oxide (NO) donor on steroid synthesis, growth and apoptosis of buffalo granulosa cells (GCs) in vitro. Follicular fluid of antral follicles (3-5 mm diameter) was aspirated and GCs were cultured in 0 (control), $10^{-3}$, $10^{-5}$, $10^{-7}$, $10^{-9}\;M$ of SNP for 48 h. To evaluate whether this effect was reversible, GCs were cultured in presence of $10^{-5}\;M$ SNP+1.0 mM $N^{\omega}$-nitro-L-arginine methyl ester (L-NAME) a NO synthase (NOS) inhibitor or hemoglobin (Hb, $1.0{\mu}g$) as NO scavenger. Nitrate/nitrite concentration was evaluated by Griess method, progesterone and estradiol concentrations by RIA and apoptosis by TUNEL assay. SNP ($10^{-3}$, $10^{-5}$, $10^{-7}\;M$) significantly (p<0.05) inhibited estradiol and progesterone synthesis, growth, disorganized GCs aggregates and induced apoptosis in a dose dependent manner. However, $10^{-9}\;M$ SNP induced the progesterone synthesis and stimulated GCs to develop into a uniform monolayer. Combination of SNP $10^{-5}$ M+L-NAME strengthened the inhibitory effect while, SNP+Hb together reversed these inhibitory effects. In conclusion, SNP at greater concentrations ($10^{-3}$, $10^{-5}$ and $10^{-7}\;M$) has a cytotoxic effect and it may lead to cell death whereas, at a lower concentration ($10^{-9}\;M$) induced progesterone synthesis and growth of GCs. These findings have important implications that NOS derived NO are involved at physiological level during growth and development of buffalo GCs which regulates the steroidogenesis, growth and apoptosis.

• Proceedings of the KAIS Fall Conference
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• 2010.11a
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• pp.488-490
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• 2010

최근 심각한 환경오염 문제와 화석 에너지 고갈로 차세대 청정 에너지 개발에 대한 중요성이 증대되고 있다. 그중에서 태양정지는 공해가 적고, 자원이 무한적이며 반 영구적인 수명을 가지고 있어 미래에너지 문제를 해결할 수 있는 에너지원으로 기대되고 있다. 본 연구에서는 P3HT(regioregular poly(3-hexylthiophene))와 PCBM(fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester)을 전자 도너와 억셉터 물질을 하나의 브랜드로 광 활성층을 형성하는 BHJ(bulk hetero junction)구조를 갖는 고분자 유기 박막 태양전지를 각각 Toluene, Mono-Chlorobenzene, Dichlorobenzene에 $60^{\circ}C$, 200rpm으로 약 12시간동안 1wt%로 교반(Stirring)한 후에 중량비(1:1 wt%)로 혼합하여 스핀코팅(Spin-coating)으로 제작하였고, 완성된 소자의 광활성층 면적은 0.04cm2이며, $150^{\circ}C$에서 후속 열처리 공정을 통해 특성 향상이 측정 되었다. 태양전지 소자 구조는 Glass / ITO / PEDOT:PSS / P3HT : PCBM / Al이다. 전류-전압, FF(Fill Factor), 변환효율 측정을 위해 solar simulator를 AM1.5 조건(100 mW/cm2)으로 이용하였으며, 소자의 최대 전류밀도는 12mA/$cm^2$, 개방전압은 0.566V이고 F.F(Fill Factor)는 55.2%이고 변환효율은 3.7%이다. 후속 열처리후 더욱 좋은 성능을 갖게 되었고, 최대 효율은 Dichl orobenzene일 때 이다.

• Korean Journal of Pharmacognosy
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• v.37 no.2 s.145
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• pp.67-73
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• 2006

The butanol extracts of Agrimonia pilosa (BAP) induced dose-dependent vascular relaxation of phenylephrine-precontracted aorta, which was abolished by removal of functional endothelium. Pretreatment of the endothelium-intact aortic tissues with $N^G$-nitro-L-arginine methyl ester (L-NAME) and 1H-[1,2,4]-oxadiazole-[$4,3-{\alpha}$]-quinoxalin-1-one(ODQ) inhibited the relaxation induced by BAP. BAP-induced vascular relaxation was also markedly attenuated by addition of verapamiI, while the relaxant effect of BAP was not blocked by indomethacine, glibenclamide, tetraethylammonium (TEA), atropine, or propranolo. In addition, incubation of endothelium-intact aortic rings with BAP increased the vascular production of cGMP. These results suggest that BAP relaxes vascular smooth muscle via endothelium-dependent nitric oxide/cGMP signaling pathway, which may be causally related with L-type $Ca^{2+}$ channels.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.589-593
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• 2007

재생 가능한 자원인 동식물성 기름을 원료로 제조되는 수송용 연료 바이오디젤은 낮은 대기오염물질 배출과 $CO_2$ Neutral 특성으로 환경친화적인 연료로 인정을 받으며 전세계적으로 그 생산량이 급격히 증가하고 있다. 대부분의 상용화 공정은 염기촉매를 이용한 전이에스테르화 반응에 근거하고 있으며 높은 생산성을 위해 연속 공정을 채택하고 있다. 원료유 중의 유리지방산(free fatty acid, FFA)은 염기 촉매와 반응하여 지방산염(Soap)과 수분을 생성하며 반응촉매의 투입양을 증가시카고 반응 후에 글리세롤과 지방산 메틸에스테르와의 분리를 어렵게 만든다. 높은 수율과 후속공정의 부하를 줄이기 위해서는 식물성 원료유 중의 FFA는 고체 산촉매 하에서 메탄올과 에스테르화 반응시켜 전환 제거되어야 한다. 본 연구에서는 고체산 촉매인 Amberlyst-15을 충전한 4단 PBR(Packed Bed Reactor, 충전율 60%(v/v))에서 반응시간과 반응온도에 따른 대두원유의 전처리 효율을 조사하였으며 최적 전처리 조건을 도출하였다. 최적 전처리 조건에서 대두원유는 초기 산가 1.6에서 0.4-0.6으로 연속 전처리할 수 있었다. 본 연구에서는 연속 흐름 반응기인 PFR(Plug Flow Reactor)와 4단 CSTR(Continuous Stirred Tank Reactor)에서 균질계 촉매인 KOH 존재하에 대두유와 메탄올과의 전이에스테르화 반응 특성을 조사하였으며 각 연속 반응시스템에서 최적 운전 조건을 도출하였다. PFR 반응기에서 반응온도, 반응시간, 반응물 흐름방향, static mixer(SM) 개수에 따른 반응특성을 조사한 결과, PFR에서의 최적 반응조건은 하향류 흐름 방향과 3개의 SM를 설치한 조건에서 반응시간 5.8분, 반응온도 90$^{\cdot}C$, 메탄올:오일 몰비 9:1, KOH 농도 0.8%로 도출되었다. CSTR 반응기에서는 반응온도와 체류시간에 따른 반응특성을 조사하였으며 최적반응 조건으로 반응온도 80$^{\cdot}C$, 메탄올/오일 몰비 9:1, KOH 농도 0.8%, 체류시간 18.4분, 교반속도 250rpm로 조사되었다.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.127-134
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• 1984

As a series of studies to clarify clonorchicidal substances in body surface mucus of some freshwater fishes, the substance in the epidermal mucus of Cyprinus carpio was isolated by silica gel column and thin layer chromatography and analysed for its chemical nature. Wormicidal trial was done in vitro, and the results obtained are summarized as follows: The mucus was extracted by ethyl ether and separated into 4 fractions by column chromatography using benzene as solvent. The second fraction with yellowish red colour among them showed the strongest clonorchicidal effect. The yellowish red fraction obtained by column chromatography was then fractionated into 6 spots by thin layer chromatography with petrol/ etherjchloroform (30/70, v/v), and the Rf. 0.714 spot among the 6 spots showed the strongest effect. The Rf. 0.714 spot was further fractionated into 6 spots by thin layer chromatography with benzene/acetone (90/10, vlv), and the Rf. 0.800 spot among the later 6 spots revealed the strongest effect. The Rf. 0.800 spot was chromatographed on column with benzene and 2 fractions were obtained. The second fraction of light brown colour represented the final purified fraction. By these Purification Procedures, clonorchicidal substance was Purified 15-fold with 0.035 yield from the mucus of C. carpio, and 10mg of the final fraction killed the cercaria in 26 min, the metacercaria in 115 min, and the adult in 443 min. Infra red and nuclear magnetic resonance spectrometric analysis of the purified substance revealed that the substance belongs to an ethyl ester of unsaturated fatty acid with 2 double bonds, 15 methylene groups and 1 methyl group.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.617-625
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• 2012

Tree peony is a traditional famous flower of China, and plays an important role in Chinese traditional culture. But the floral scent of tree peony in vivo is little known. In this study, in order to explore the floral composition of tree peony, floral volatiles of six cultivars, including Paeonia suffruticosa 'Zhaofen' (ZF), P. suffruticosa 'Luoyanghong' (LYH), P. ostii 'Fengdanbai' (FDB), P. ${\times}$ lemonei 'High noon' (HN), P. ${\times}$ lemonei 'Renown' (R), and P. rockii 'Gaoyuanshenghuo' (GYSH) were collected by dynamic headspace and then identified by Automated Thermal Desorption-Gas Chromatography/Mass Spectometry. The results showed that floral fragrances of the six cultivars were qualitatively and quantitatively distinct. A total of 105 volatiles involving ten categories were detected. But not all volatile categories were emitted from these cultivars. The six peony cultivars emitted some shared compounds and peculiar compounds. The total released amounts of volatiles emitted from six cultivars were found significantly different, which was greatest for 'GYSH'. The most abundant volatile compounds detected from 'ZF', 'LYH', 'FDB', 'HN', 'R', and 'GYSH' were respectively ${\alpha}$-pinene, 2,3-dihydroxy propanal, 3-methyl-1-butanol, 2-ethyl-1-hexanol, acetic acid 1-methylethyl ester, and 5-ethyl-2,2,3-trimethyl heptane. This result may contribute to exploring the biosynthesis and emission mechanism of floral scent in tree peony.

• Journal of Chest Surgery
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• v.28 no.8
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• pp.742-746
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• 1995

The present study was aimed at investigating possible transmitter mechanisms in the endothelial cell layer in regulating the tone of the vascular smooth muscle. The thoracic aorta was isolated from the anesthetized male white rabbits and its helical strips were prepared. Electrical field stimulation was delivered to platinum wire electrodes positioned parallel to the vessel segment preconstricted with phenylephrine [3.5x10-6 mol/L at a distance of 1.5-2.0 mm. The electrical stimulation [70 V, 5 msec, 0.5-200 Hz caused either relaxation only [34% or a biphasic response [prolonged relaxation following a weak and transient contraction, 66% . The relaxation response was frequency- dependent, and at 200 Hz a complete relaxation was noted. Mechanical rubbing of the endothelial layer abolished or greatly attenuated the relaxation. The relaxation was also markedly attenuated in the presence of NG-nitro- L-arginine methyl ester [10-3mol/L or procaine hydrochloride [3.5x10-4mol/L . Tetrodotoxin,guanethidine, atropine or indomethacin failed to block or enhance the relaxation response to electrical field stimulation. It is concluded that the vascular endothelium in the aorta contains diffusible substances that regulates the function of the smooth muscle layer, in which relaxation is more prominent than contraction. Their release by the electrical stimualtion in vitro may not involve classic neuronal transmitter release mechanisms or metabolism of arachidonic acids by cyclooxygenase. The release of the relaxing agents may require an increase in cytosolic calcium level. The chemical nature of the relaxant may be, to a large extent, nitric oxide.

• Environmental Engineering Research
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• v.23 no.2
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• pp.205-209
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• 2018

The spectral composition of light can affect the growth and biochemical composition of photosynthetic microalgae. This study examined the use of light filtering through a solution of soluble colored additives, a cost-effective method to alter the light spectrum, on the growth and lipid production of an oleaginous microalga, Nannochloropsis gaditana (N. gaditana). Cells were photoautotrophically cultivated under a white light emitting diode (LED) alone (control) or under a white LED that passed through a solution of red and yellow color additive (4:1 ratio) that blocked light below 600 nm. The specific growth rate was significantly greater under filtered light than white light ($0.2672d^{-1}$ vs. $0.1930d^{-1}$). Growth under filtered light also increased the fatty acid methyl ester (FAME) yield by 22.4% and FAME productivity by 80.0%, relative to the white light control. In addition, the content of saturated fatty acids was greater under filtered light, so the biodiesel products had better stability. These results show that passing white light through an inexpensive color filter can simultaneously enhance cellular growth and lipid productivity of N. gaditana. This approach of optimizing the light spectrum may be applicable to other species of microalgae.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.1
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• pp.79-82
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• 1997

The present study was aimed to explore an interaction between endothelium-derived nitric oxide (NO) and atrial natriuretic peptide (ANP) systems in normotensive and hypertensive states. Rats were made two-kidney, one clip (2K1C) hypertensive and supplemented with either $N^G-nitro-L-arginine$ methyl ester (L-NAME, 5 mg/100 ml drinking water) or L-arginine hydrochloride (400 mg/100 ml drinking water). One group supplied with normal tap water served as control. Sham-clipped rats were also divided into the L-NAME, L-arginine, and control groups. The plasma levels and atrial contents of ANP were determined at day 28 following clipping the renal artery. In 2K1C rats, the plasma level of ANP was higher and the atrial content was lower than in the sham-clipped control. L-Arginine increased the atrial content of ANP in association with a decreased plasma ANP, whereas L-NAME significantly affected neither parameter. The increase of blood pressure in 2K1C rats was not affected by L-arginine or L-NAME. In sham-clipped rats, the plasma level of ANP was significantly increased by L-NAME along with an increase in blood pressure. On the contrary, L-arginine did not affect the blood pressure or plasma ANP. The atrial content of ANP was significantly altered neither by L-arginine nor by L-NAME. These results suggest that NO plays a tonic inhibitory role on the ANP release with concomitant increases of the atrial tissue content. In addition, hypertension is suggested to modify the release and tissue storage of ANP.