• Title/Summary/Keyword: silica-gel

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The Isolation and Antioxidative Effects of Vitexin from Acer palmatum

  • Kim Jin Hwa;Lee Bum Chun;Kim Jin Hui;Sim Gwan Sub;Lee Dong Hwan;Lee Kyung Eun;Yun Yeo Pyo;Pyo Hyeong Bae
    • Archives of Pharmacal Research
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    • v.28 no.2
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    • pp.195-202
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    • 2005
  • Free radicals and reactive oxygen species (ROS) caused by UV exposure or other environmental factors are critical players in cellular damage and aging. In order to develop a new antiphotoaging agent, this work focused on the antioxidant effects of the extract of tinged autumnal leaves of Acer palmatum. One compound was isolated from an ethyl acetate soluble fraction of the A. palmatum extract using silica gel column chromatography. The chemical structure was identified as apigenin-8-C-beta-D-glucopyranoside, more commonly known as vitexin, by spectral analysis including LC-MS, FT-IR, UV, $^{1}H-$, and $^{13}C-NMR$. The biological activities of vitexin were investigated for the potential application of its anti-aging effects in the cosmetic field. Vitexin inhibited superoxide radicals by about $70\%$ at a concentration of $100\;{\mu}g/mL$ and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals by about $60\%$ at a concentration of $100\;{\mu}g/mL$. Intracellular ROS scavenging activity was indicated by increases in dichlorofluorescein (DCF) fluorescence upon exposure to UVB $20\;mJ/cm^2$ in cultured human dermal fibroblasts (HDFs) after the treatment of vitexin. The results show that oxidation of 5-(6-)chloromethyl-2',7'-dichlo-rodihydrofluorescein diacetate ($CM-H_{2}DCFDA$) is inhibited by vitexin effectively and that vitexin has a potent free radical scavenging activity in UVB-irradiated HDFs. In ROS imaging using a confocal microscope we visualized DCF fluorescence in HDFs directly. In conclusion, our findings suggest that vitexin can be effectively used for the prevention of UV-induced adverse skin reactions such as free radical production and skin cell damage.

Induction of Growth Hormone by the Roots of Astragalus membranaceus in Pituitary Cell Culture

  • Kim, Chung-Sook;Ha, Hye-Kyung;Kim, Jin-Sook;Kim, Yun-Tai;Kwon, Sun-Chang;Park, Sie-Won
    • Archives of Pharmacal Research
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    • v.26 no.1
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    • pp.34-39
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    • 2003
  • The traditional Asian medicinal herb, roots of Astragalus (A.) membranaceus (Leguminosae), is used for many purposes, some of which are purported to stimulate the release of growth hormone in vivo. Extracts of A. membranaceus were tested to determine whether they stimulate the release of growth hormone in rat pituitary cell culture. A. membranaceus was extracted sequentially with 80% ethanol (fraction A), n-hexane (fraction B); the test compound from the herbal extraction was isolated using silica gel column chromatography and was identified with spectral data. Test compound was also extracted by traditional boiling water methods. Induction of growth hormone in pituitary cell culture was conducted with isolated compounds and extracted fractions of A. Radix (dried roots of A. membranaceus). The fraction A was not active in the rat pituitary cell culture, but the fraction B derived from the ethanol fraction stimulated the release of growth hormone in culture. Six compounds from fraction B (1-6) were isolated and identified previously. The compounds 1,2-benzendicarboxylic acid diisononylester (1), $\beta$-sitosterol (2), and 3-Ο-$\beta$-D-galactopyranosyl-$\beta$-sitosterol (5) did not induce growth hormone release in the culture. Formononetin (3), 9Z, 12Z-octadecadienoic acid (4), stigmast-4-en-6$\beta$-o1-3-one (6) and 98-E, a mixture of 1'-9, 12-octadecadienoic acid (Z,Z)-2',3'-dihydroxy-propylester (7) and 1'-hexadecanoic acid-2',3'-dihydroxy-propylester (8) stimulated the release of growth hormone in the rat pituitary cell culture significantly compared to the control. In conclusions, four compounds isolated from extracts of A. Radix induced growth hormone release in the rat pituitary cell culture. The 98-E isolate was the most active inducer of growth hormone release.

Metal-Dinitrosyl Complexes(Ⅳ) : Synthesis and Characterization of Symmetric and Asymmetric Dinuclear Molybdenum and Tungsten Complexes (금속-디니트로실 착물 (제 4 보) : 몰리브덴과 텅스텐의 대칭 및 비대칭 이핵 착물의 합성과 특성)

  • O, Sang O;Mo, Seong Jong
    • Journal of the Korean Chemical Society
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    • v.38 no.7
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    • pp.485-495
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    • 1994
  • Several new symmetric and asymmetric homo and hetero dinuclear complexes of the type $[Cl(dppp)(NO)_2M({\mu}-pyz)M'(NO)_2(dppp)Cl][ClO_4]_2$ and $[Cl(phen)(NO)_2M({\mu}-pyz)M'(NO)_2(dppp)Cl][ClO_4]_2$(M,M'= Mo or W; phen = 1,10-phenanthroline; dppp = 1,3-bis(diphenylphosphino)propane; pyz = 1,4-pyrazine) were synthesized in three-steps starting from $[M(NO)_2Cl_2]_n(M = Mo, W)$. The final products were purified by eluting it through silica gel column ($2{\times}20$ cm) with acetone as the eluent. Characterization of these complexes and some related complexes was accomplished through UV-vis., $^1H$-NMR, $^{13}C$-NMR and IR spectroscopies as well as elemental analysis. The infrared spectra indicate that the NO groups occupy cis-positions of the octahedral. The $^1H$ and $^{13}C-NMR$ data for the new compounds revealed a dimeric structures with bridged pyz.

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Chemical Constituents of the Root of Dystaenia takeshimana and Their Anti-Inflammatory Activity

  • Kim, Ju-Sun;Kim, Jin-Cheul;Shim, Sang-Hee;Lee, Eun-Ju;Jin, Wen-Yi;Bae, Ki-Hwan;Son, Kun-Ho;Kim, Hyun-Pyo;Kang, Sam-Sik;Chang, Hyeun-Wook
    • Archives of Pharmacal Research
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    • v.29 no.8
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    • pp.617-623
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    • 2006
  • In our ongoing search for bioactive compounds originating from the endemic species in Korea, we found that the hexane and EtOAc fractions of the MeOH extract from the root of Dystaenia takeshimana (Nakai) Kitagawa (Umbelliferae) showed cyclooxygenase-2 (COX-2) and 5- lipoxygenase (5-LOX) dual inhibitory activity by assessing their effects on the production of prostaglandin $D_2\;(PGD_2)$ and leukotriene $C_4\;(LTC_4)$ in mouse bone marrow-derived mast cells. By activity-guided fractionation, five coumarins, viz. psoralen (2), xanthotoxin (3), scopoletin (4), umbelliferone (5), and (+)-marmesin (6), together with ${\beta}-sitosterol$ (1), were isolated from the hexane fraction, and two phenethyl alcohol derivatives, viz. 2-methoxy-2-(4'-hydroxyphenyl)ethanol (7) and 2-hydroxy-2-(4'-hydroxyphenyl)ethanol (8), three flavonoids, viz. apigenin (9), luteolin (10), and cynaroside (11), as well as daucosterol (12) were isolated from the EtOAc fraction using silica gel column chromatography. In addition, D-mannitol (13) was isolated from the BuOH fraction by recrystallization. Two of the coumarins, scopoletin (4) and (+)- marmesin (6), the two phenethyl alcohol derivatives (7, 8) and the three flavonoids (9-11) were isolated for the first time from this plant. Among the compounds isolated from this plant, the five coumarins as well as the three flavonoids showed COX-2/5-LOX dual inhibitory activity. These results suggest that the anti-inflammatory activity of D. takeshimana might in part occur via the inhibition of the generation of eicosanoids.

[ $\beta$ ]-Secretase (BACE1) Inhibitors from Sanguisorbae Radix

  • Lee, Hee-Ju;Seong, Yeon-Hee;Bae, Ki-Hwan;Kwon, Soon-Ho;Kwak, Hye-Min;Nho, Si-Kab;Kim, Kyung-A;Hur, Jong-Moon;Lee, Kyung-Bok;Kang, Young-Hwa;Song, Kyung-Sik
    • Archives of Pharmacal Research
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    • v.28 no.7
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    • pp.799-803
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    • 2005
  • In the course of screening anti-dementia agents from natural products, two $\beta$-secretase (BACE1) inhibitors were isolated from the ethyl acetate soluble fraction of Sanguisorbae Radix by the activity-guided purification using silica gel, Sephadex LH-20, and RP-HPLC. They were identified as 1,2,3-trigalloyl-4,6-hexahydroxydiphenoyl-$\beta$-D-glucopyranoside (Tellimagrandin II, 1) and 1,2,3,4,6-pentagalloyl-$\beta$-D-glucopyranoside (2) and were shown to non-competitively inhibit $\beta$-secretase (BACE1) with the $IC_{50}$ values of $3.10{\times}10^{-6}M\;and\;3.76{\times}10^{-6}M$, respectively. The Ki values of 1 and 2 were $6.84{\times}10^{-6}M\;and\;5.13{\times}10^{-6}M$. They were less inhibitory to asecretase (TACE) and other serine proteases such as chymotrypsin, trypsin, and elastase, suggesting that they were relatively specific inhibitors of BACE1.

Characteristics of Zeolites (Zeolite의 특성)

  • Im, Goeng
    • The Journal of Natural Sciences
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    • v.6 no.1
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    • pp.103-108
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    • 1993
  • Zeolites were discovered as a natural mineral more than two hundred ago. In the beginning, the mineral was used as ion-exchange material and adsorbent. After the end of World War II , however, a variety of zeolites have become available in large amounts because of the establishment of low temperature synthesis and the discobery of natural zeolite deposits of sedimentary origin. Various uses of xeolite were developed utilizing the unique crystal strucrure and function of these minerals. In connection with this development remakable progress has also been made in basic stuides on the related geology and mineralogy, crystallization from sols and gels, structure, ion exchange, adsorption and cataiysis. As a result, zeolites, which had been known only as mineral specimens displayed in museums. established a firm position among the high-technology masterials with excellent functional capabilities.

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Formation of Luteoskyrin by Penicillium islandicum (Penicillium islandicum에 의한 황변미독(黃變米毒) Luteoskyrin의 생성(生成))

  • Kim, Yong-Hwa;Lee, Su-Rae
    • Korean Journal of Food Science and Technology
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    • v.10 no.1
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    • pp.46-51
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    • 1978
  • One of yellowed rice toxins, luteoskyrin, was investigated with respect to its identification, quantitation and producibility by Penicillium islandicum isolated from deteriorated rice. 1) Luteoskyrin was best resolved by thin-layer chromatography with silica gel G plate impregnated with 0. 5 N oxalic acid and acetone : n-hexane : water (6 : 3 : 1.5, upper layer) solvent system. The isolated yellow spot showed maximum absorption bands at 426 and 448 nm and changed to purple color upon exposure to sunlight for $2{\sim}3$ hours. 2) Detection limit for luteoskyrin was 4 ppm in elution-colorimetry and 0.1 ppm in densitometry after TLC. Assuming that the tolerance for luteoskyrin in rice is set below 3.68 ppm, densitometry is usable for its screening in grain samples 3) Producibility of luteoskyrin by Pen. islandicum was shown to be 11 mg/g mycelial mat in liquid culture and 40 mg/g autoclaved rice.

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Estimation of polycyclic aromatic hydrocarbons emission from sewage sludge of sewerage treatment plants in Korea

  • Kim, Dong-Hwan;Hwang, Jong-Seob;Lee, Min-Hee;Ok, Gon
    • Journal of Environmental Science International
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    • v.12 no.11
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    • pp.1167-1171
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    • 2003
  • Polycyclic aromatic hydrocarbons (PAHs) are an important group of organic contaminants present in sewage sludge, due to their persistence, toxic, bioaccumulative and long range transfer. These characters make themselves as Persistent Organic Pollutants(POPs) in Long Range Transboundary Air Pollutions convention(LRTAP) of Europe. A method of the gas chromatographicmass spectrometric (GCMS) determination of PAHs present in sewage sludge was developed and applied to analyzed samples from five sewerage treatment plants (SWTPs), having different treatment types. PAHs were extracted from freeze-dried samples by toluene 16 hours in a soxhlet extraction system. The sludge extracts were cleaned-up by an activated silica gel column chromatography. The sum of the 16 US Environmental Protection Agency PAHs sewage sludge samples varied from 2.44 to 4.82 $\mu\textrm{g}$/g. Concentration of emission carcinogen PAHs(PAHcarc), such as Benzo(a)anthracene, Benzo(b)f1uoranthene, Benzo(k)f1uoranthene, Benzo(a)pyrene, Dibenzo(a,h)anthracene and Indeno( 1,2,3-cd)pyrene ranged from 0.62 to 1.03 $\mu\textrm{g}$/g. The total amount of PAHs emission from sewage sludge in Korea was calculated as a top-down approach. PAHs and $\Sigma$PAHcarc from sewage treatment plants had emitted to environment by several pathway. The highest amount of emission to the environment was remarked in the ocean dumping(PAHs and $\Sigma$PAHcarc emissions were 1155.95 kg/year and 5040.32 kg/year, respectively).

Analysis of Functional Constituents in Mulberry (Morus alba L.) Twigs by Different Cultivars, Producing Areas, and Heat Processings

  • Choi, Sang Won;Jang, Yeon Jeong;Lee, Yu Jin;Leem, Hyun Hee;Kim, Eun Ok
    • Preventive Nutrition and Food Science
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    • v.18 no.4
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    • pp.256-262
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    • 2013
  • Four functional constituents, oxyresveratrol 3'-O-${\beta}$-D-glucoside (ORTG), oxyresveratrol (ORT), t-resveratrol (RT), and moracin (MC) were isolated from the ethanolic extract of mulberry (Morus alba L.) twigs by a series of isolation procedures, including solvent fractionation, and silica-gel, ODS-A, and Sephadex LH-20 column chromatographies. Their chemical structures were identified by NMR and FABMS spectral analysis. Quantitative changes of four phytochemicals in mulberry twigs were determined by HPLC according to cultivar, producing area, and heat processing. ORTG was a major abundant compound in the mulberry twigs, and its levels ranged from 23.7 to 105.5 mg% in six different mulberry cultivars. Three other compounds were present in trace amounts (<1 mg/100 g) or were not detected. Among mulberry cultivars examined, "Yongcheon" showed the highest level of ORTG, whereas "Somok" had the least ORTG content. Levels of four phytochemicals in the mulberry twigs harvested in early September were higher than those harvested in early July. Levels of ORTG and ORT in the "Cheongil" mulberry twigs produced in the Uljin area were higher than those produced in other areas. Generally, levels of ORTG and ORT in mulberry twigs decreased with heat processing, such as steaming, and microwaving except roasting, whereas those of RT and MC did not considerably vary according to heat processing. These results suggest that the roasted mulberry twigs may be useful as potential sources of functional ingredients and foods.

Effect of Extract from Paeoniae radix on Rabbit Platelets (작약 추출물의 혈소판 작용에 관한 연구)

  • 박영현;손동주
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.3
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    • pp.511-515
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    • 2002
  • Paeoniae radix has been considered as one of the most important crude drugs used in traditional oriental medicine and has been employed as a circulatory tonic in care of weakness, night sweats, and lumbar pain, etc. Platelet activation plays an important role in thrombosis and haemostasis. Active compounds for the inhibition of platelet activation from Paeoniae radix were extracted and fractionated into five fractions. Its fraction two and three of ethyl acetate extract inhibited the aggregation of washed rabbit platelets induced by collagen. Two active compounds, bezoyloxypaeoniflorin and paeoniflorin, were isolated from fraction two and three by silica gel column and high performance liquid chromatography. The chemical structures were determined by comparison of their proton and carbon nuclear magnetic resonance spectra. Benzoyloxypaeoniflorin showed strong inhibition at the concentration of 100 ug/mL against collagen-induced washed rabbit platelets aggregation. It is suggested that Paeoniae radix has become food material to prevent a cardiovascular disease.