• 한국식품과학회지
• /
• 제25권4호
• /
• pp.379-385
• /
• 1993

Phenol성 물질로서 hydroxyl기가 두개인 caffeic acid와 세개인 phloroglucinol을 methyl linoleate에 첨가하여 산화시키면서 활성화 효과와 산화생성물을 분석하였다. Methyl linoleate에 대한 $37^{\circ}C,\;3{\sim}9$일간의 산화반응에서 caffeic acid 및 phloroglucinol 첨가군은 ${\alpha}-tocopherol$ 첨가군에 비해 높은 항산화성을 나타내었다. 이 때 산화생성물로서는 methyl linoleate(ML)군은 methyl-8-(2-furyl)-octanoate, 9,13-trans, cis hydroperoxide isomer 9,13-trans, trans hydroperoxide isomer 및 9-TMSO-12, 13-epoxy-10-octadecenoate로 나타났으며, 기간이 경과함에 따라 9,13-trans, trans isomer에 대한 9,13-trans, cis isomer의 비율이 낮아졌다. Caffeic acid 첨가군(CML)에서는 methyl-8-(2-furyl)-octanoate, 9-trans, cis hydroperoxide isomer 및 9-trans, trans hydroperoxide isomer였으며, 13-hydroxy isomer는 검출되지 않았다. Caffeic acid의 농도를 높일수록 9-trans, trans isomer에 대한 9-trans, cis isomer의 비율이 높아지는 것으로 나타났으며, 이 때 가장 주된 산화물인 caffeic quinone이 생성되는 것으로 보아 caffeic acid와 같은 o-dihydroxy cinnamate들은 lipid media에서 산화가 쉽게 일어나는 것으로 나타났다. 또한 phloroglucinol 첨가군(PML)의 산화 생성물들은 methyl-8-(2-furyl)-octanoate, 9-trans, cis hydroperoxide isomer, 9-trans, trans hydroperoxide isomer 및 9-hydroxy-12,13-epoxy-10-octadecenoate로서 CML군과 유사한 경향을 보였으나 phloroglucinol은 반응 9일째에도 산화되지 않았다.

• Biomolecules & Therapeutics
• /
• 제19권2호
• /
• pp.201-205
• /
• 2011

Although various biological activities of resveratrol have been extensively studied, most reports have focused on trans-resveratrol and little attention has been paid to the cis-isomer. In this study, the effect of cis-resveratrol on platelet activity was examined and compared with that of the trans-isomer. Treatment with cis-resveratrol resulted in inhibition of platelet aggregation induced by thrombin, collagen or ADP, which are representative aggregation-inducing agents, and the trans-isomer elicited the same effects. These effects were concentration-dependent in the range of 1-100 ${\mu}M$. However, the potency of the cis-isomer was much lower than that of the trans-isomer; the $IC_{50}$ values for the cis-isomer versus the trans-isomer were $31{\pm}12$ vs $151{\pm}3$, $161{\pm}3$ vs $91{\pm}4$, and $601{\pm}15$ vs $251{\pm}6\;{\mu}M$ for thrombin-, collagen- and ADP-induced aggregation, respectively. These results indicate that cis-resveratrol has a less potent anti-platelet activity, compared with the trans-isomer, and raise the possibility that the biological activities of the cis-isomer may be different from those of the trans-isomer. It will be necessary to evaluate the activity of cis-resveratrol independently of the trans-isomer.

• Journal of Photoscience
• /
• 제1권1호
• /
• pp.61-62
• /
• 1994

Upon exposure to daylight, trans-2,2'-dimethoxyazobenzene isomerized to give a equilibrium mixture of 70% cis and 30% trans isomer. The high photo-steady concentration of cis isomer is discussed compared with that of azobenzene.

• Bulletin of the Korean Chemical Society
• /
• 제30권5호
• /
• pp.1143-1146
• /
• 2009

[$Mn_{12}O_{12}(azo-L)_{16}(H_2O)_4$] (1), a new Mn12 single molecule magnet containing a photochromic azobenzene ligand, has been successfully synthesized by substitution of acetate ligand of Mn12 with 6-[4-{4-hexyloxyphenyl( azo)}-phenoxy]hexanoic-1-acid. The reversible photoisomerization of the azobenzene group was confirmed by UV-visible absorption spectroscopy. The temperature and field dependence of dc susceptibility and the temperature and the frequency dependence of ac susceptibility were measured for the cis and the trans isomer of 1. The magnetization value of the cis isomer in dc measurement is higher than that of the trans isomer. The cis isomer of 1 has a slower relaxation because cis-trans photoisomerization of the azobenzene group in peripheral ligands induces changes in its structure and dipole moment.

• 한국환경과학회지
• /
• 제18권12호
• /
• pp.1325-1330
• /
• 2009

The fumigant 1,3-dichloropropene (1,3-D) was recently proposed as a direct replacement for methyl bromide ($CH_3Br$) in soil fumigation. This study was conducted to better understand behavior phase partitioning, diffusion and volatilization of 1,3-D as affected by isomer. The Henry's law constant(KH) of cis-1,3-D and trans-1,3-D was 0.058 and 0.037 at $20^{\circ}C$, respectively. $K_H$ of cis form of 1,3-D was higher than that of trans form of 1,3-D. To compare with volatilization of 1,3-D isomer, soil column [70 cm (length)${\times}$12 cm (i.d.)] included a shank injection at 30 cm with 300 kg $ha^{-1}$. Maximum cis-1,3-D and trans-1,3-D concentration reached 57 mg $L^{-1}$ and 39 mg $L^{-1}$ at 30 cm depth at 1h after application. Cumulatively, after 10 days, 51.8% and 43.57% of applied cis-1,3-D and trans-1,3-D was emitted via volatilization, respectively. The total losses of cis-1,3-D were significantly greater than that of trans-1,3-D. Finally, cis-1,3-D and trans-1,3-D, such as isomer are dominant of 1,3-D fates in soil.

• 한국임상수의학회지
• /
• 제20권1호
• /
• pp.66-73
• /
• 2003

Numerous physiological effects are attributed to conjugated linoleic acid(CLA). The purpose of this study is to consider these effects with respect to the cis-9, trans-11 and trans-10, cis-12 CLA isomer. Both isomers are natural products. The c9,t11-CLA isomer is the principal dietary form of CLA, but the concentrations of this isomer and the t10,c12-CLA Isomer in dairy products or beef vary depending on the diet fed to cows or steers, respectively. The influence of dietary CLA isomers on the immune response was examined, body weight and weight ratio of organ to body of Balb/C mice. Mice were divided into four groups of 8 mice. Balb/C mice were fed the experimental diets supplemented with 1% CLA (c9,t11-CLA isomer : t10,c12-CLA isomer = 2:3) (Group 1), 1% CLA (c9,t11-CLA isomer t10,c12-CLA isomer : 1:1) (Group 2), 1% safflower oil (Group 3) or nothing (Control) for 3 weeks. After 3 weeks, serum, gut lumen lavage, fat, liver, spleen and thymus were taken. Measurement of total immunoglobulin were executed using sandwich ELISA. Serum levels of IgA and IgM showed that group fed with t10,c12-CLA isomer significantly were higher than group fed with c9,tl1-CLA isomer. In addition serum level of IgG showed that group fed with t10,c9-CLA isomer significantly were lower than group fed with c9,tl1-CLA isomer. However, no significantly differences were observed in the serum IgE and secretory IgA. Weight ratio of spleen to body showed no significant differences. In weight ratio of liver and thymus to body, tl0,c9-CLA isomer significantly were respectively higher than group fed with c9,t11-CLA isomer. In weight ratio of fat to body, tl0,c9-CLA isomer significantly were respectively lower than group fed with c9,tl1-CLA isomer. In conclusion, t10,c12-CLA isomer produced a situation favorable for immunopotentiative effect and body composition. But it should be protected against hepatomegaly induced lipid accumulation in liver.

• 한국식품과학회지
• /
• 제25권6호
• /
• pp.614-619
• /
• 1993

Methyl linoleate에 ${\alpha}-Tocopherol$을 첨가하여(TML) $37^{\circ}C$에서 9일간 산화시키면서 산화생성물의 확인 및 생성기구에 대하여 GC/MS를 사용하여 검토하였다. TML군에서의 산화 생성물들은 methyl octanoate와 methyl-8-(2-furyl)-octanoate 및 9,13-trans, cis isomer와 9,13-trans, trans isomer로 밝혀졌다. 전보의 methyl linoleate(ML)에서의 산화생성물과 비교하여 볼 때 9-TMSO-12,13-epoxy-10-octadecenoate 대신 methyl octanoate가 생성되었다. ${\alpha}-Tocopherol$의 주된 산화물인 ${\alpha}-Tocopherol$ quinone은 반응 6일부터 생성되었으며, ${\alpha}-Tocopherol$은 aqueous media보다 lipid media에서 산화가 빨리 진행되는 것으로 나타났다. Methyl linoleate의 산화에 의한 생성물들의 생성과정 기구를 추정한 결과, 우선 methyl-9,13-hydroxy-octadecadienoate가 생성되고 다시 methyl-9-hydroxy-10 trans, 12 trans-octadecadienoate로부터 methyl-8-(2-furyl)-octanoate와 9-TMSO-12,13-epoxy-10-ortadecenoate 및 methyl octanoate가 생성된 것으로 사료되었다.

• Journal of Animal Science and Technology
• /
• 제46권6호
• /
• pp.967-974
• /
• 2004

본 연구는 여 러 conjugated linoleic acid(CLA) 이성체가 돼지 지방전구세포의 분화에 미치는 영향을 구영하기 위해 수행하였다. 돼지 지방전구세포는 갓난 돼지의 등 지방에서 분리해서 성숙지방세포로 분화될 때 까지 배양했다. 여러 CLA 이성체를 배양중의 세포에 처리했다. 세포분화는 세포배양이 끝난 후 세포의 glycerol-3-phosphate의 활성도를 측정함으로써 구명했다. 20$\mu$M과 50$\mu$M의 transto-cis12 CLA 이성체는 돼지 지방천구세포의 분화를 억제했고，한펀 cis9-cisl1 이성체는 세포분화를 촉진했다. cis9-trans 11 과 trans9-trans11 이생체는 세포분화에 아무런 영향을 마치지 않았다. CLA의 세포분화에 미치는 작용은 배양후기 (day8${\sim}$14) 보다 배양전기(day 0${\sim}$ 8)에 더 두드러지게 나타냈다. 위의 결과는 여러 CLA 이성체는 돼지 지방천구세포 분화에 각각 다른 작용을 가짐을 나타낸다.

• Archives of Pharmacal Research
• /
• 제20권4호
• /
• pp.346-350
• /
• 1997

The synthesis of cis- and trans-1,6-dihydroxypyrrolizidine starting from trans-4-hydroxy-L-proline and their evaluation as glycosidase inhibitors are reported. The cis-isomer was found to be a potent inhibitor against .alpha.-glucosidase and showed weak inhibitory effect against other glycosidases. The trans-isomer exhibited weak inhibitions of b-glucosidase and amylo-glucosidase and poor inhibition of other glycosidases.

• 한국식품과학회지
• /
• 제25권4호
• /
• pp.307-312
• /
• 1993

Linoleic acid methylester와 토코페놀류$({\alpha}-,\;{\beta}-,\;{\gamma}-,\;{\delta}-tocopherol$과 ${\alpha}-,\;{\gamma}-,\;{\delta}-tocotrienol)$를 사용한 model system에서의 자동산화과정에서 온도$(40,\;60,\;80^{\circ}C)$와 산소의 양 $(0,\;10,\;20%\;O_2)$에 따르는 항산화효과를 고찰하였다. Linoleic acid methylester에서 생성된 주요 산화생성물인 13-cis/trans-, 13-trans/trans-, 9-trans/cis-, 9-trans/trans-hydroperoxide를 HPLC를 이용하여 분석하였으며, 그 양적 변화로 항산화정도를 비교하였다. 모든 토코페롤류$({\alpha}-tocotrienol$제외)는 $60^{\circ}C$ 범위에서 항산화효과가 있었다. ${\alpha}-tocopherol$, ${\alpha}-tocotrienol$ and ${\delta}-tocotrienol$의 경우 $80^{\circ}C$ 범위에서 산화촉진효과가 관찰되었다. $40^{\circ}C$ 범위에서는 주로 cis/trans-hydroperoxide가 많이 생성되었고 $80^{\circ}C$ 범위에서는 trans/trans-hydroperoxide가 많이 생성되었다. $80^{\circ}C$ 범위의 hydroperoxide 생성량간의 오차가 심한 구간을 제외한 $40^{\circ}C/10%,\;O_2$에서부터 $60^{\circ}C/20%,\;O_2$까지의 산화구간에서 cis/trans-: trans/trans-hydroperoxides의 비율은 ${\alpha}-T>{\alpha}-T_3>{\gamma}-T>{\beta}-T>{\gamma}-T_3>{\delta}-T>{\delta}-T_3$의 순으로 고찰되어, 토코페롤류 중 ${\alpha}-tocopherol$이 가장 낮은 항산화효과가 있는 것으로 나타났다.