• Title/Summary/Keyword: Conjugated addition

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Indium and Gallium-Mediated Addition Reactions

  • Lee, Phil-Ho
    • Bulletin of the Korean Chemical Society
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    • v.28 no.1
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    • pp.17-28
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    • 2007
  • Indium and gallium have emerged as useful metals in organic synthesis as a result of its intriguing chemical properties of reactivity, selectivity, and low toxicity. Although indium belongs to a main metal in group 13, its first ionization potential energy is very low and stable in H2O and O2. Therefore, indium-mediated organic reactions are of our current interest. On the basis of these properties of indium, many efficient indium-mediated organic reactions have been recently developed, such as the addition reactions of allylindium to carbonyl and iminium groups, the indium-mediated synthesis of 2-(2-hydroxyethyl)homoallenylsilanes, the indiummediated allylation of keto esters with allyl halides, sonochemical Reformatsky reaction using indium, the indium-mediated selective introduction of allenyl and propargyl groups at C-4 position of 2-azetidinones, the indium-mediated Michael addition and Hosomi-Sakurai reactions, the indium-mediated β-allylation, β- propargylation and β-allenylation onto α,β-unsaturated ketones, the highly efficient 1,4-addition of 1,3-diesters to conjugated enones by indium and TMSCl, and the intramolecular carboindation reactions. Also, we found gallium-mediated organic reactions such as addition reactions of propargylgallium to carbonyl group and regioselective allylgallation of terminal alkynes.

Low Molecular Weight Polyethylenimine-Mitochondrial Leader Peptide Conjugate for DNA Delivery to Mitochondria

  • Choi, Joon-Sig;Choi, Min-Ji;Go, Gyeong-Su;Rhee, Byoung-Doo;KimPak, Young-Mi;Bang, In-Seok;Lee, Min-Hyung
    • Bulletin of the Korean Chemical Society
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    • v.27 no.9
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    • pp.1335-1340
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    • 2006
  • It has been found that a number of diseases are associated with mutations in the mitochondrial DNA. Therapeutic gene delivery to mitochondria has been suggested as a clinical option for these diseases. In this study, we developed a gene carrier to mitochondria by the conjugation of mitochondrial leader peptide (LP) to polyethylenimine (PEI). Mitochondrial LP conjugated PEI (PEI-LP) was synthesized with low molecular weight PEI (2,000 Da, PEI2K). Gel retardation assay showed that PEI2K-LP formed complexes at a 1.0/1 weight ratio. In addition, PEI2K-LP protected DNA from the enzymatic degradation for at least 60 min, while naked DNA was completely degraded within 20 min. PEI2K-LP was compared with LP conjugated high molecular weight PEI (25,000 Da, PEI25K) in terms of toxicity and delivery efficiency. MTT assay showed that PEI2K-LP had much lower cytotoxicity than PEI25K-LP to 293 cells. In addition, cell-free DNA delivery assay showed that PEI2K-LP delivered more DNA to mitochondria at a 1.8/1 weight ratio than naked DNA or PEI. This result suggests that PEI2K-LP may be useful for the development of mitochondrial gene therapy system with lower cytotoxicity.

Targeted Delivery of VP1 Antigen of Foot-and-mouth Disease Virus to M Cells Enhances the Antigen-specific Systemic and Mucosal Immune Response

  • Kim, Sae-Hae;Lee, Ha-Yan;Jang, Yong-Suk
    • IMMUNE NETWORK
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    • v.13 no.4
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    • pp.157-162
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    • 2013
  • Application of vaccine materials through oral mucosal route confers great economical advantage in animal farming industry due to much less vaccination cost compared with that of injection-based vaccination. In particular, oral administration of recombinant protein antigen against foot-and- mouth disease virus (FMDV) is an ideal strategy because it is safe from FMDV transmission during vaccine production and can induce antigen-specific immune response in mucosal compartments, where FMDV infection has been initiated, which is hardly achievable through parenteral immunization. Given that effective delivery of vaccine materials into immune inductive sites is prerequisite for effective oral mucosal vaccination, M cell-targeting strategy is crucial in successful vaccination since M cells are main gateway for luminal antigen influx into mucosal lymphoid tissue. Here, we applied previously identified M cell-targeting ligand Co1 to VP1 of FMDV in order to test the possible oral mucosal vaccination against FMDV infection. M cell-targeting ligand Co1-conjugated VP1 interacted efficiently with M cells of Peyer's patch. In addition, oral administration of ligand-conjugated VP1 enhanced the induction of VP1-specific IgG and IgA responses in systemic and mucosal compartments, respectively, in comparison with those from oral administration of VP1 alone. In addition, the enhanced VP1-specific immune response was found to be due to antigen-specific Th2-type cytokine production. Collectively, it is suggested that the M cell-targeting strategy could be applied to develop efficient oral mucosal vaccine against FMDV infection.

Effect of acid whey and freeze-dried cranberries on lipid oxidation and fatty acid composition of nitrite-/nitrate-free fermented sausage made from deer meat

  • Karwowska, Malgorzata;Dolatowski, Zbigniew J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.1
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    • pp.85-93
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    • 2017
  • Objective: This study evaluated the effect of acid whey and freeze-dried cranberries on the physicochemical characteristics, lipid oxidation and fatty acid composition of nitrite-free fermented sausage made from deer meat and pork fat. Antioxidant interactions between acid whey and cranberry compounds were also explored. Methods: Four formulations of fermented venison sausage were prepared: F1 (control), F2 (with 5% liquid acid whey), F3 (with 0.06% of freeze-dried cranberries), and F4 (with 5% liquid acid whey and 0.06% of freeze-dried cranberries). Each sample was analyzed for pH, water activity ($a_w$), heme iron content, 2-thiobarbituric acid reactive substances (TBARS) value and conjugated dienes at the end of the manufacturing process and at 30 and 90 days of refrigerated storage. Fatty acid composition was measured once at the end of the manufacturing process. Results: At the end of ripening, all samples presented statistically different values for a pH range of 4.47 to pH 4.59. The sum of the unsaturated fatty acids was higher, while the conjugated diene and the TBARS values were lower in sausages with freeze-dried cranberries as compared to the control sausage. The highest content of heme iron (21.52 mg/kg) at day 90 was found in the sausage formulation with the addition of freeze-dried cranberries, which suggests that the addition of cranberries stabilized the porphyrin ring of the heme molecule during storage and thereby reduced the release of iron. The use of liquid acid whey in combination with cranberries appears to not be justified in view of the oxidative stability of the obtained products. Conclusion: The results suggest that the application of freeze-dried cranberries can lower the intensity of oxidative changes during the storage of nitrite-free fermented sausage made

Effect of Concentrate Level on the Formation of Conjugated Linoleic Acid and Trans-octadecenoic Acid by Ruminal Bacteria when Incubated with Oilseeds In Vitro

  • Wang, J.H.;Song, M.K.;Son, Y.S.;Chang, M.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.5
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    • pp.687-694
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    • 2002
  • An in vitro study was conducted to examine the effect of addition level of concentrate on fermentation characteristics and long-chain unsaturated fatty acids composition, especially conjugated linoleic acid (CLA) and trans-octadecenoic acid (t-FA) by mixed ruminal bacteria when incubated with linseed or rapeseed. Four levels (0.83, 1.25, 1.67 and 2.08%, w/v) of concentrate and ground oilseeds (linseed or rapeseed; 0.83%, w/v) were added to mixed solution of strained rumen fluid with artificial saliva (1:1, v/v) in the glass jar with a glass lid equipped with stirrer, and was incubated anaerobically for 24 h at $39^{\circ}C$. Addition level of concentrate slightly reflect on pH and ammonia concentration of the culture solution at the various incubation times when incubated with both linseed and rapeseed. Total VFA concentration slightly increased with incubation times and concentrate levels for incubations with oilseeds. While CLA composition had a clearly increasing trend with incubation time when incubated with linseed, percent CLA was relatively stable when incubated with rapeseed. Percent CLA, however, had a clearly decreasing trend with concentrate level throughout incubation times with significances at 3 h incubations when incubated with linseed (p<0.038) and rapeseed (p<0.0009). The differences in compositions of t-FA were relatively small among concentrate levels for both incubations with linseed and rapeseed. The ratios of t-FA to CLA were lower for linseed with increased proportion of CLA than for rapeseed.

Delivery of Hypoxia Inducible Heme Oxygenase-1 Gene Using Dexamethasone Conjugated Polyethylenimine for Protection of Cardiomyocytes under Hypoxia

  • Kim, Hyun-Jung;Kim, Hyun-Ah;Choi, Joon-Sig;Lee, Min-Hyung
    • Bulletin of the Korean Chemical Society
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    • v.30 no.4
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    • pp.897-901
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    • 2009
  • Heme oxygenase-1 (HO-1) is an anti-inflammatory and anti-apoptotic protein and has been applied to various gene therapy researches. However, constitutive expression of HO-1 may induce deleterious side effects. In this research, hypoxia inducible HO-1 expression plasmid, pEpo-SV-HO-1, was constructed with the erythropoietin (epo) enhancer and simian virus 40 (SV40) promoter to avoid these unwanted side effects. Dexamethasone conjugated polyethylenimine (PEI-Dexa) was used as a gene carrier. It was previously reported that dexamethasone protected cardiomyocytes from apoptosis under hypoxia. In this research, PEI-Dexa reduced the caspase-3 level in hypoxic H9C2 cardiomyocytes as a derivative of dexamethasone, suggesting that PEI-Dexa is an anti-apoptotic reagent as well as a gene carrier. pEpo-SV-HO-1 was transfected to H9C2 cardiomyocytes using PEI-Dexa and the cells were incubated under normoxia or hypoxia. HO-1 expression was induced in the pEpo-SV-HO-1 transfected cells under hypoxia. In addition, cell viability under hypoxia was higher in the pEpo-SV-HO-1 transfected cells than the pEpo-SV-Luc transfected cells. Also, caspase-3 level was reduced in the pEpo-SV-HO-1 transfected cells under hypoxia. In addition to the anti-apoptotic effect of PEI-Dexa, hypoxia inducible HO-1 expression by pEpo-SVHO- 1 may be helpful to protect cardiomyocytes under hypoxia. Therefore, pEpo-SV-HO-1/PEI-Dexa complex may be useful for ischemic heart disease gene therapy.

The In vitro Effects of Nano-encapsulated Conjugated Linoleic Acid on Stability of Conjugated Linoleic Acid and Fermentation Profiles in the Rumen

  • Heo, Wan;Kim, Eun Tae;Cho, Sung Do;Kim, Jun Ho;Kwon, Seong Min;Jeong, Ha Yeon;Ki, Kwang Seok;Yoon, Ho Baek;Ahn, Young Dae;Lee, Sung Sill;Kim, Young Jun
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.3
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    • pp.365-371
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    • 2016
  • This study was aimed to evaluate the stability of conjugated linoleic acids (CLAs) by nano-encapsulation against in vitro ruminal biohydrogenation by microbial enzymatic conversion. CLAs (free fatty acid form of CLA [CLA-FFA], nano-encapsulated CLA-FFA, triglyceride form of CLA [CLA-TG], and nano-encapsulated CLA-TG) were used in the in vitro fermentation experiments. When Butyrivibrio fibrisolvens (B. fibrisolvens) was incubated with CLA-FFAs, the concentrations of cis-9, trans-11 CLA and vaccenic acid (VA) slightly was decreased and increased by nano-encapsulation, respectively. When B. fibrisolvens was incubated with CLA-TG, the concentrations of cis-9, trans-11 CLA and VA decreased, but these were increased when B. fibrisolvens was incubated with nano-encapsulated CLA-TG. The nano-encapsulation was more effective against the in vitro biohydrogenation activity of B.fibrisolvens incubated with CLA-FFA than with CLA-TG. In the in vitro ruminal incubation test, the total gas production and concentration of total volatile fatty acids incubated with nano-encapsulated CLA-FFA and CLA-TG were increased significantly after 24 h incubation (p<0.05). Nano-encapsulated CLA-FFA might, thus, improve the ruminal fermentation characteristics without adverse effects on the incubation process. In addition, nano-encapsulated CLA-FFA increased the population of Fibrobacter succinogenes and decreased the population of B. fibrisolvens population. These results indicate that nano-encapsulation could be applied to enhance CLA levels in ruminants by increasing the stability of CLA without causing adverse effects on ruminal fermentation.

Effect of Conjugated Linoleic Acid on the Proliferation of the Human Colon Cancer Cell Line, HT-29 (Conjugated Linoleic Acid가 대장암 세포인 HT-29의 증식에 미치는 영향)

  • 김은지;조한진;김석종;강영희;하영래;윤정한
    • Journal of Nutrition and Health
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    • v.34 no.8
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    • pp.896-904
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    • 2001
  • Conjugated linoleic acid(CLA) is a group of positional and geometric isomers of linoleic acid(LA) and exhibits anticarcinogenic activity in multiple experimental animal models. Cis-9,trns-11(c9t11) and trans-10,cis-12(t10c12) CLA are the principal isomers found in foods. The present study was performed to determine whether CLA and the two isomers inhibits HT-29 cell proliferation and to assess whether such an effect was related to changes in secretion of eicosanoids. Cells were incubated in serum-free medium with various concentrations(0 to 20$\mu$M) of CLA or LA. CLA inhibited cell proliferation in a dose-dependent manner, with maximal inhibition(70 $\pm$ 1%) observed at 20$\mu$M concentration after 96 hours. However, LA had no effect at the same concentration range. To compare the ability of c9f11 and t10c12 to inhibit cell proliferation, cells were incubated with increasing concentrations(0 to 4$\mu$M) of these isomers. T10c12 inhibited cell proliferation in a dose-dependent manner. A 66 $\pm$ 2% decrease in cell number was observed within 96 hours after addition of 4$\mu$M t10c12. By contrast, c9t11 had no effect. The concentrations of CLA and the two isomers in the plasma membrane were increased when they were added to the incubation medium. However, they did not alter the levels of arachidonic acid in plasma membrane. To assess whether the proliferation inhibiting effect of CLA was related to changes in eicosanoid production, prostaglandin E$_2$(PGE$_2$) and leukotriene B$_4$(LTB$_4$) concentrations in conditioned media were estimated by a competitive enzyme immunoassay. Both CLA and t10c12 increased the production of materials reactive to PGE$_2$ and LTB$_4$ antibodies in a dose-dependent manner. By contrast, c9t11 had no effect. These results indicate that inhibition of HT-29 cell proliferation by CLA is attributed to the effect of the t10v12 isomer. The materials reactive to PGE$_2$ and LTB$_4$ antibodies may inhibit growth stimulatory effect of arachidonic acid-derived eicosanoids on HT-29 cell proliferation.

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The Effects of Conjugated Linoleic Acid and/or Exercise on Body Weight and Body Composition in College Women with High Body Fat Mass (Conjugated linoleic acid의 섭취와 운동여부가 체지방 함량이 높은 여대생의 체중과 체성분 변화에 미치는 영향)

  • Son, Say-Jin;Lee, Ji-Eun;Park, Eun-Kyo;Paik, Eun-Young;Lee, Ji-Eun;Kim, Young-Jae;Kim, Tae-Wook;Kim, Dae-Han;Kim, Jong-Hyuck;Jung, In-Kyung;Kim, Jung-Hyun
    • Korean Journal of Food Science and Technology
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    • v.41 no.3
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    • pp.307-312
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    • 2009
  • To investigate the effects of conjugated linoleic acid (CLA) and/or exercise on body fat mass and weight, college women of normal weight (2130%) were recruited for this study. The participants were divided into 4 groups: placebo-no exercise, placebo-exercise, CLA-no exercise, and CLA-exercise groups. Three grams of either a placebo (corn oil) or CLA were taken every day for 12 weeks, and the exercise groups performed 80 minutes of aerobic and anaerobic exercise three times a week for 12 weeks. There were no differences in nutrient intakes among the groups. The CLA-exercise group had significantly lower body weight, BMI and body fat mass compared to the placebo-no exercise group. In addition, the HDL-cholesterol levels of subjects in the CLA-no exercise and CLA-exercise groups significantly increased compared to those in the placebo-no exercise group. These results suggest that a combination of CLA supplementation with exercise could efficiently reduce body fat mass and body weight compared to CLA supplementation or exercise alone.

Effect of Dietary Conjugated Linoleic Acid on Growth Performance, Carcass Characteristics and Muscular Fatty Acid Composition in Broiler (사료내 Conjugated Linoleic Acid 첨가수준이 육계의 생산성, 도체특성 및 근내 지방산 조성에 미치는 영향)

  • Kim, Young-Jik;Kim, Byung-Ki;Yoon, Yong-Bum
    • Food Science of Animal Resources
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    • v.28 no.4
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    • pp.451-456
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    • 2008
  • This study was conducted to determine the effects of dietary supplementation with conjugated linoleic acid (CLA) feeding levels (0, 0.5, 1.0, 1.5, and 2.0%) on the carcass characteristics, growth performance, serum cholesterol, and fatty acid in thigh of chicken meat. Two hundred broiler (Arbor Acre Broiler, male) were randomly assigned to five groups and were fed for five weeks and slaughtered. Thigh muscle was used for determining fatty acid composition. There was no significant difference in growth performance, such as weight gain, feed intake and feed conversion by CLA levels. Among carcass characteristics, percentage of carcass, thigh, breast, and drumstick was not influenced by the dietary CLA levels, but abdominal fat was significantly reduced with the increased CLA amount in the broilers diets (p<0.05). Higher CLA levels increased HDL-C and reduced total cholesterol and LDL-C (p<0.05). As the dietary CLA levels increased, muscular palmitic acid (saturated fatty acid) levels was increased, but the rates of oleic acid, linoleic acid, and arachidonic acid (unsaturated fatty acid) were decreased. In addition. CLA isomers were linearly increased with the increase in dietary CLA levels (p<0.05). As a conclusion, 2% of CLA feeding is possible to maximize accumulation of CLA in meat, but changes in fatty acid composition is not profitable. Therefore, 1% of CLA feeding i,j considered to be proper for accumulation of CLA and minimization of the change in fatty acid.