• Bulletin of the Korean Chemical Society
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• 제11권5호
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• pp.391-395
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• 1990

The kinetics of thermnal cis-trans isomerization reaction of 1-bromopropene(1-BP) was studied at temperatures from 620.8 to 753.15 K over the pressure range 0.17-50.3 Torr. Both the inhibition effect by cyclohexene or propene and the catalytic effect by HBr showed a radical process as the main mechanism of the isomerization. In the suppression of the radical process by the inhibitors, the molecular process also contributed to overall reaction rate. The reactions demonstrated the first order kinetics under both uninhibited and inhibited conditions and could be represented by the expressions (R = 1.987 cal/mol/K) $k_{un}/s^{-1} = (3.45{\pm}1.50){\times}10^{11}$exp$[(- 48100{\pm}2000)/RT]\;k_{ink}/s^{-1} = (2.98{\pm}1.40){\times}10^{12}$exp$[(- 55800{\pm}1800)/RT]$> where $k_{un}$ is the observed rate constant of cis-1-bromopropene(1-B$P_c$) to trans-1-bromopropene(1-B$P_t$) under uninhibited condition at initial pressure of 50 Torr and $k_{ink}$ is the rate constant under maximal inhibition by cyclohexene. The ratio of rate constants for bromine atom elimination from the allylic hydrogen of reactant(1-BP) and from the inhibitors, propene and cyclohexene, were measured from the observed rates of the uninhibited and inhibited reactions. The inhibition efficiencies of cyclohexene and propene were compared kinetically from the rate constants and shown to give good agreement with the previous results reported from other alkyl bromide pyrolyses.

• 한국식품영양과학회지
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• 제40권12호
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• pp.1734-1742
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• 2011

본 실험에서는 들기름에 약 60%로 존재하는 ${\alpha}$-linolenic acid를 알칼리 이성질화 반응을 이용하여 CLnA(conjugated linolenic acid)와 CLA(conjugated linoleic acid)를 생산하고자 하였다. 들기름을 가수분해한 뒤에 10분에서 6시간까지의 반응시간과 5%에서 60%까지의 NaOH 농도에서 CLnA와 CLA의 생성을 표준물질과 함께 GC와 spectrophotometer를 이용하여 확인하였다. 시간에 따른 CLnA와 CLA 함량 변화는 나타나지 않았으나, NaOH 농도가 증가함에 따라서 CLnA와 CLA가 유의적으로 증가하는 경향을 보였다. 반응조건 중, 20% KOH, $180^{\circ}C$, 1시간 반응에서 14.5%와 14%의 CLnA와 CLA의 함량을 나타냈으며, 42.2%의 C18:3 conjugated 이성질체가 생성되었다. 이성질체를 확인하기 위해 GC-MS 그리고 FT-IR을 이용한 실험을 수행하였다. GC-MS의 ion peak 분석 결과, conjugated 형태에서만 특징적으로 나타나는 m/z=91 ion peak를 확인할 수 있었고, CLA와 CLnA의 분자량이 C18:2와 C18:3과 일치하는 것을 확인할 수 있었다. 그리고 NIST Library에서 검색된 methyl 9c, 11t-CLA, methyl 10t, 12c-CLA와 methyl 9cis, 11trans, 13trans-octadecatrienoate의 결과와 일치하는 ion peak를 형성하였다. 이 외의 이성질체는 FT-IR 분석 결과, 높은 trans fatty acid 함량을 보여 알칼리 이성질화 반응 시, $180^{\circ}C$의 높은 열에 반응을 하여 trans 형태의 conjugated form이 다량 생성된 것으로 사료된다. conjugated 이성질체의 생성 양을 높이기 위해 들기름 가수분해물을 우레아 분별을 한 뒤에, ${\alpha}$-linolenic acid의 함량을 70%까지 높인 뒤에 알칼리 이성질화 반응을 수행한 결과 CLnA의 생성 양이 16.6%까지 증가한 것을 확인할 수 있었다. 그러나 CLnA 이외의 conjugated 지방산 함량의 변화는 없었다.

• Journal of Nutrition and Health
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• 제36권7호
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• pp.661-666
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• 2003

The study was designed to compare the anti-carcinogenic effect of conjugated linoleic acid (CLA) isomers on colon carcinogenesis in 1,2-dimethylhydrazine (DMH)-treated rats by determining the levels of apoptosis, cell proliferation, eicosanoids and 1,2-diacylglycerol (DAG) in colonic mucosa. Sixty male Sprague Dawley rats were randomly divided into 3 groups depending on the types of CLA isomers, i.e. BT group (no CLA contained), CLA-C group (cis-9, trans11 isomer contained), and CLA- T group (trans-10, cis-12 isomer contained). The experimental diet was composed of protein at 20%, carbohydrate at 56.2%, and fat at 14.5% including 0.8% CLA isomers by weight. The experimental diet was fed for 14 weeks with the initiation of intramuscular injection of DMH, which was injected twice a week for 6 weeks to give total dose of l80mg per kg body weight. Two CLA isomers (c9t11 and t10c12) significantly increased the relative percentage of apoptosis but reduced cell proliferation in mucosal cell and also the levels of PGE$_2$, TXB$_2$, and DAG in colonic mucosa. However, there was no significant differences in anti-carcinogenic effect between c9t11 isomer and t10c12 isomer. Overall, colon carcinogenesis could be significantly inhibited by CLA isomers by increasing apoptosis and reducing cell proliferation, the levels of eicosanoids and DAG in colonic mucosa.

• Bulletin of the Korean Chemical Society
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• 제19권11호
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• pp.1211-1216
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• 1998

Bis(diethyldithiocarbamato)ioxomolybdenum(VI), cis-MoO2(S2CNEt2)2, 1, reacted with chlorotrimethylsilane (Me33SiCl) to give a seven-coordinate, pentagonal bipyramidal complex MoOC12(S2CN]Et2)2, 3, in which the oxo ligand is trans to the chloride ligand and the two chloride ligands are mutually cis. The monooxo molybdenum complex bis(diethyidithiocarbamato)oxomolybdenum(IV), MoO(S2CNEt2)2, 2, reacted with phenyl isocyanate (PhNCO) to give an Mo dimer MO2{μ-N(CONPh)Ph}(μ-NPh)(NPh)2(S2CNEt2)2, 4, which contains an Mo-Mo bond, two diethyldithiocarbamato ligands, two terminal imido (NPh) ligands, and two bridging hnido (NPh) ligands. One of the two bridging NPh ligands seemed to have been attacked by the electrophilic phenyl isocyanate carbon, which suggests that the bridging imido NPh ligand is more nucleophilic than the terminal one. Crystallographic data for 3: monoclinic space group P21/c, a=8.908(l) Å, b=17.509(3) Å, c=12.683(2) Å, β=110.15(1)°, Z=4, R(wR2)=0.0611(0.1385). Crystallographic data for 4-THF: orthorhombic space group P212121, a=17.932(4) Å, b=22.715(5) Å, c=11.802(3) Å, Z=4, R(wR2)=0.0585(0.1286).

• 식물조직배양학회지
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• 제25권2호
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• pp.89-93
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• 1998

Tomato phenylalanine ammonia-lyase 5 (tPAL5) was identified that alternate initiation sites were utilized differentially in response to environmental stimuli (Lee et al, 1992b). In this study, we tried to look into tissue -or cell- specific expression pattern of tPAL5 gene by fusing with ${\beta}-glucuronidase$ (GUS) gene in transgenic tobacco plants. In transgenic plants, root and stem extracts contained 8~12 fold higher levels of GUS activity than petiole or leaf tissue while the highest levels of induction was observed from leaf tissue by mechanical wounding (5~11 fold). In trans-sections of stems and petioles, GUS activity was restricted to phloem cells(outer region) of developing vascular bundle and mainly at apical tip region in the root tissues. The levels of GUS activity was drastically reduced (10~12 fold reduction) when the 5'-upstream region of tPAL5 gene (-1151bp from ATG codon) was deleted up to -665. The levels of GUS expression, however, raised up by 6~8 fold when deleted up to -455. Therefore, we conclude that there are positive cis-elements at the region -1151 to -1008 and at -455 to -195 while the negative cis-element is at -1008 to -455.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.222-226
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• 2003

The effects of dietary sources of C18:2 n-6 or C18:3 n-3 fatty acids on the occurrence of conjugated linoleic acid (CLA) and time-dependent changes of free fatty acid fractions in rumen contents were investigated. Sheep (n=4) fitted with rumen fistula were used in a 44 Latin square design wxith each 14 d period. Sheep were fed one of four diets consisting of grass hay and concentrates in a ratio of 70:30. Dietary treatments were 100% concentrates (served as the control), and concentrates were replaced by safflower seed at 30% (SFS), safflower meal at 18% - safflower oil at 12% (SFO), and safflower meal at 18%-linseed oil at 12% (LNO). At the end of each experimental period, rumen contents from each sheep were collected before feeding and at 1, 3, 6 and 12 h after feeding. The levels of cis-9, trans-11 CLA in free fatty acid fraction were considerably increased in all treated groups relative to the control, but not significantly. The increase in cis-9, trans-11 CLA was slightly higher in SFS and SFO groups than group fed diet containing linseed oil. The level of cis-9, trans-11 CLA in free fatty acid fraction was reached to the maximum value at 1hr after feeding and, thereafter gradually decreased to near the value before feeding. The generation of trans-11 C18:1 was significantly higher in all treated groups than that of control. The level of trans-11 C18:1 was linearly increased after feeding of experimental diets, reaching the maximum value at 3 h. Feeding of diets containing polyunsaturated fats to sheep resulted in a marked increase in the levels of trans-11 C18:1 and a slight increase of CLA in free fatty acid fraction of rumen contents. Our results support that endogenous synthesis of CLA from trans-11 C18:1 may be involved the primary source of CLA in dairy product. (Asian-Aust.

• 미생물학회지
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• 제43권2호
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• pp.100-105
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• 2007

홀스타인 건유우의 반추위에서 분리한 혼합 곰팡이에 첨가한 linoleic acid가 biohydrogenation 과정 중 생산되는 지방산의 농도와 종류를 측정하고, 최종 산물로 생산되는 지방산이 trans-11 vaccenic acid인지 stearic acid인지 조사하기 위하여 본 연구를 수행하였으며 결과는 다음과 같다. 반추위 혼합 박테리아 배양구에 linoleic acid 용액을 첨가한 결과, 배양 90분 이내에 100%의 linoleic acid가 stearic acid로 biohydrogenation되었다. 반면에 linoleic acid 용액을 반추위 혼합 곰팡이에 첨가한 결과 24시간 이내에 모든linoleic acid는 conjugated linoleic acid (cis-9, trans-11)와 trans-11 vaccenic acid로 biohydrogenation되었다. Linoleic acid가 함유된 혼합곰팡이 처리구는 배양시간이 증가할수록 stearic acid의 농도도 소량 증가하는 경향을 보였다. 또한 linoleic acid가 함유되지 않은 혼합곰팡이 대조구에서도 배양시간이 증가할수록 stearic acid 농도가 처리구와 비슷하게 증가하는 경향을 나타내었다. 그러나 혼합 박테리아의 linoleic acid 첨가구에서는 배양시간이 증가할수록 stearic acid의 농도가 급격하게 증가하는 것을 조사되어 반추위 혼합곰팡이의 stearic acid생산은 linoleic acid의 biohydrogenation과 무관하게 생산되는 것으로 조사되었다. 따라서 반추위 혼합 곰팡이에 의한 linoleic acid biohydrogenation의 최종 산물은 trans-11 vaccenic acid로 판단되며, 혼합 박테리아는 stearic acid로 나타났다.

• Journal of Animal Science and Technology
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• 제48권4호
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• pp.521-532
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• 2006

본 실험은 대두유 또는 아마유를 in vitro 방법으로 배양 할 때, 탄수화물원의 첨가수준이 반추위 박테리아에 의한 bio-hydrogenation과 CLA 생성에 미치는 효과를 조사하였다. 4수준(0%, 0.3%, 0.6% 그리고 0.9%, w/v)의 혼합된 탄수화물원(glucose, cellobiose, soluble starch, 1:1:1, w/w/w)과 두 종류의 oil을 cellulose powder에 흡착시킨 형태로 각각 60mg씩 인공타액(120ml)과 반추위액(30ml)이 혼합된 배양액(150ml)에 넣은 다음 39℃에서 12시간동안 혐기적으로 배양하였다. 배양액의 pH와 암모니아 농도는 두 종류 oil을 첨가한 배양액 모두에서 탄수화물원의 첨가 수준이 높을수록 pH와 암모니아 농도가 낮았다(P<0.05). 탄수화물원의 첨가 수준이 증가할수록 total VFA 생성량 역시 증가되었으나(P<0.01) 첨가한 oil 간의 차이는 없었다. 배양시간이 경과됨에 따라 탄수화물원의 첨가수준이 높을수록 propionate의 조성비율이 증가된 반면(P<0.001) acetate와 butyrate의 조성비율은 감소되었다. 배양 후 3시간이 경과하였을 때 배양액 내 oleic acid의 조성비율은 대두유에 비하여 아마유를 첨가한 배양액에서 낮았으나(P<0.001) linoleic acid의 비율은 높았다(P<0.001). 이와는 달리 탄수화물원의 수준이 증가될수록 stearic acid(P<0.05), CLA(P<0.01) 및 cis-9, trans-11 CLA(P<0.001)의 조성비율은 감소되었으나, linoleic acid의 조성 비율은 증가되었다(P<0.05). Linolenic acid의 조성비율에 있어서는 첨가된 oil의 종류와 첨가된 탄수화물원의 수준간의 상호작용이 있는 것으로 나타났는데(P<0.001), 12시간의 배양종료 후 대두유 첨가구에 비해 아마유 첨가구에서 stearic acid(P<0.01), oleic acid(P<0.001), 그리고 trans-11C18:1(P<0.01)의 조성비율이 감소된 반면, linoleic acid(P<0.001)와 linolenic acid(P<0.01)의 조성비율은 증가되었다. 탄수화물원의 첨가수준이 증가될수록 stearic acid와 총 CLA의 조성비는 감소되었으나(P<0.01), trans-11-C18:1(P<0.05)와 linoleic acid(P<0.01)의 조성비율은 증가되었다. 배양 12시간 후 배양액 내의 oleic acid (P<0.05), linoleic acid(P<0.05) 및 linolenic acid(P<0.01)의 조성비율에 있어서는 첨가한 oil의 종류와 첨가한 탄수화물원의 수준간의 상호작용이 있었는데, 탄수화물원의 첨가수준이 감소됨에 따라 cis-9, trans-11 CLA와 trans-10, cis-12 CLA의 조성비 역시 감소되는 경향이었으나 첨가한 oil의 종류에 대한 영향은 거의 받지 않았다. 본 실험의 결과를 종합해 볼 때, 탄수화물의 첨가수준과 oil의 첨가는 반추미생물의 bio-hydrogenation 작용 및 CLA 생성에 영향할 수 있는 것으로 여겨진다.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.634-640
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• 2005

The reaction of cis-[Cr([14]-decane)(OH$_2)_2]^+$ ([14]-decane = rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-teraazacyclotetradecane) with auxiliary ligands {$L_a$ = citrate(cit)} leads to a new dimeric complex cis-[{Cr([14]-decane)($\mu$-cit)}$_2](ClO_4)_2$. This binuclear complex has been structurally characterized by a combination of elemental analysis, conductivity, IR and Vis spectroscopy, mass spectrometry, and X-ray crystallography. Analysis of the crystal structure of cis-[{Cr([14]-decane)($\mu$-cit)})($_2]^+$ reveals that each chromium has a distorted octahedral coordination environment and citrato ligands are monodentate to the two chromium atoms via the carboxyl groups. For dimeric complex the bridging geometry is as follows: Cr$\ldots$Cr = 7.361 $\AA$; Cr-O(average) = 1.958 (8) $\AA$; Cr-N range = 2.108 (9)-2.147(9) $\AA$; N(1)-Cr-N(3) (equatorial position) = 98.0(4)$^{\circ}$; N(2)-Cr-N(4) (axial position) = 166.4(4)$^{\circ}$; O(1)-Cr-N(2) = 98.1(4)$^{\circ}$; O(3)-Cr-N(4) = 96.6(3)$^{\circ}$; O(1)-Cr-O(3) = 90.4$^{\circ}$. The FAB mass spectrum of the dimeric complex displays peak due to the molecular ions cis-[{Cr([14]-decane)($\mu$-cit)})($_2]^+$ at m/z 1053.

• 한국식품과학회지
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• 제28권3호
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• pp.440-445
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• 1996

Methyl linoleate를 기질로하여 온도 및 과산화물가에 따른 monohydroperoxide 이성체의 조성변화를 $60^{\circ}C$와 $90^{\circ}C$ 그리고 $120^{\circ}C$와 $150^{\circ}C$에서 조사하여 보았다. Silica gel column으로 분획한 monohydroperoxide 분획물을 NaBH로 환원시켜 HPLC를 이용하여 분석 및 분획하였다. 각각의 이성체 분획은 trimethylsolyl ester 형태로 유도체화시킨 후 GC-MS로 확인하였다. 확인된 이성체중 기하이성체의 조성변화는 $60^{\circ}C$와 $90^{\circ}C$의 경우 9/13-OOH-trans, trans-diene이 9/13-OOH-cis, trans-diene보다 높게 나타났으나 $150^{\circ}C$의 초기단계에서는 9/13-OOH-cis, trans-diene이 9/13-OOH-trans, trans-diene 보다 다소 높게 나타났다. 한편 위치이성체의 경우에는 온도 및 과산화물가의 변화에 따라 거의 비슷한 비율을 나타내었다.