• 제목/요약/키워드: non-conjugated diene

검색결과 6건 처리시간 0.018초

Zirconocene-catalyzed Copolymerizations of Ethylene with 5-Methyl-1,4-hexadiene as Non-conjugated Diene

  • Jin, Yong-Hyun;Im, Seung-Soon;Kim, Sang-Seob;Soonjong Kwak;Kim, Kwang-Ung;Kim, Keon-Hyeong;Kim, Jungahn
    • Macromolecular Research
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    • 제10권2호
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    • pp.97-102
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    • 2002
  • The mixtures of non-conjugated dienes, 4-methyl-1,4-hexadiene and 5-methyl-1,4-hexadiene (MHD), were successfully synthesized by the reaction of isoprene with ethylene using Fe(III)-based catalyst in toluene. The conversion was over 96 mol% on the basis of the initial amount of isoprene used. The production yield for MHD was nearly 50 mol%, the other was polyisoprene. The mixtures were successfully copolymerized with ethylene by using zirconium-based metallocenes. The products were characterized by the combinations of gas chromatography, high temperature gel permeation chromatography, $^1$H NMR, $^{13}$ C NMR, high temperature $^1$H NMR, UV/visible spectroscopy, and differential scanning calorimetry. It was found that 5-methyl-1,4-hexadiene was active enough to be incorporated into the copolymer chain but the corresponding isomeric material,4-methyl-1,4-hexadiene, was inactive in metallocene-catalyzed copolymerizations. Specifically, in the zirconocene-catalyzed copolymerizations of ethylene with MHD, ansa-structure catalysts seem to be more efficient than non-bridged type zirconocene. The degree of incorporation of MHD in the resulting copolymers was able to be controlled by the amount of non-conjugated dienes used initially.

발효 대두 식품의 폴리페놀, 플라보노이드 함량과 다양한 측정 방법에 따른 항산화 활성 비교 (Total flavonoids and phenolics in fermented soy products and their effects on antioxidant activities determined by different assays.)

  • 박정우;이영진;윤선
    • 한국식생활문화학회지
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    • 제22권3호
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    • pp.353-358
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    • 2007
  • This study was conducted to compare the antioxidant activities of fermented soy products such as chungkukjang, meju and doenjang with soybeans. Total phenolic, flavonoids contents and antioxidative activities of the methanol extract of soy and fermented products were compared with specific reference to alpha-diphenyl-2-picryl-hydrozyl (DPPH) radicals scavenging effects, ferric /reducing power (FRAP), inhibition of conjugated diene formation and tyrosinase activities. Total phenolic and flavonoids contents increased in soybeans after fermentation. Fermented soy products also displayed enhanced antioxidative activities in comparison with the non-fermented soybeans. There were linear relationships between total phenolic and flavonoids contents and ferric reducing/antioxidant power of the samples. Overall, the fermented soy products showed a better antioxidant activity than soybeans. Among the 3 kinds of fermented soy products, chungkukjang, meju and deonjang, doenjang exhibited the highest levels of DPPH-free radicals scavenging activity, ferric /reducing power, inhibition of conjugated diene formation and tyrosinase activities. The fermented soy products with longer fermentation time demonstrated the higher antioxidant activities as well as higher total phenols and flavonoids in the order of doenjang > meju > chunghlkjang> soybeans.

방사선 조사선량에 따른 유지의 이화학적 성질변화 (I) (Changes of the phsico-Chemical Characteristics of oils treated by the ${\gamma}$-ray irradiation (I) -The Extracted soybean oil-)

  • 임국이
    • 대한가정학회지
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    • 제30권4호
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    • pp.77-88
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    • 1992
  • To investigate the oxidative stabilities of the ${\gamma}$-ray irradiated soybean during storage and heating and some physico-chemical characteristics of soybean and the extracted soybean oil (SBO) with/without the ${\gamma}$-ray irradiation were determined. The ${\gamma}$-ray level use in irradiation for soybean were 2.5, 5.0 and 10.0 KGY respectively and Acid Value, Peroxide Value, Conjugated Diene Value, Composed Fatty Acids amounts, and Trans Fatty Acid occurrence were determined for all samples, which were incubated at 45$\pm$1$^{\circ}C$ for 25 days heated at 180$\pm$1$^{\circ}C$ for 30 hours. And these values of the ${\gamma}$-ray treated samples were compared to those of nontreated samples. The results were obtained as follows : 1. According to the increased level of the ${\gamma}$-ray irradiation, there was little difference in Dielectric Constant, Viscosity, and the Induction Period by Rancimat. But, in case of 5.0 KGY, oxidative stability was increased more twice than that of non-irradiation. In the quantity of fatty Acids composition of the extracted soybean oil irradiated with 10.0 KGY, palmitic, oleic and linoleic acids were less increased thanb those of non-irradiation, while stearic, linolenic acids were decreased. In the case of 2.5 KGY irradiation, stearic and oleic acids were increased. 2. The Acid Value of SBO according to the ${\gamma}$-ray irradiation level was almost not change, but was 0.1 lower than that of non-irradiation during incubation (45$\pm$1$^{\circ}C$). The Peroxide Value of SBO with the ${\gamma}$-ray irradiation, was very lower than that of non-irradiation, but its effect on oxidative stability was better of SBO treated with 5.0 KGY and 10.0 KGY. In the Fatty Acids composition of SBO, palmitic, stearic, oleic acids were increased, while linoleic, linolenic acids were decreased during incubation(45$\pm$1$^{\circ}C$). This tendency was more obvious due to the ${\gamma}$-ray level. While heating(180$\pm$1$^{\circ}C$), the Acid Value of SBO treated with the ${\gamma}$-ray irradiation was decreased, the Acid Value of SBO irradiated with 2.5 KGY was the lowest. Also the peroxide Values of SBO treated with 5.0 KGY, 10.0 KGY were very lower than that of non-irradiation. Conjugated Diene Value of SBO was almost unchanged according to the ${\gamma}$-level and heating time. 3. When the methyl linoleate was irradiated with the ${\gamma}$-ray, the Trans Fatty Acid was little produced. In case of SBO with non-irradiation, the trans C18:1 was occured about 6.5~7.9%, but trans C18:2 and C18:3 were not shown, while SBO irradiated with the ${\gamma}$-ray 2.5, 5.0, 10.0 KGY, trans C18:3 and C18:2 amount in SBO were increased according to heating time, but trans C18:3 was little occured. As these results, the effects of the ${\gamma}$-ray irradiation to oil containing food were to cut down the energy for food storage and to increase oxdative stability during storge. And also it was shown to be the best that 10.0 KGY of the ${\gamma}$-ray irradiation would be applied to soybean.

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Combined Effects of Sex Hormones and Dietary Oils on Lipid Peroxidation

  • Ima-Nirwana, S.;Khalid, B.A.K;Jamaludin, M.;Merican, Z.
    • Natural Product Sciences
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    • 제1권1호
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    • pp.17-24
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    • 1995
  • The effects of orchildectomy with/without testosterone replacement in wale rats, and ovarectomy with estrogen replacement in female rats on lipid peroxidation were studied in male and female rats fed with diets fortified with 20% w/w, soybean oil or palm oil for 4 months. Serum, liver and heart homogenates were assayed for malonaldehyde and conjugated diene levels. Orchidectomy was found to reduce levels of lipid peroxidation products in the serum, liver and heart. Testosterone replacement did not increase the lipid peroxidation products to levels in the non-orchildectomised rats, while estrogen did not influence lipid peroxidation significantly. Palm oil decreased, but soybean oil increased lipid peroxidation in the liver and heart of both the castrated and sex hormone-replaced male and female rats.

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고빌리루빈혈증이 유도된 신생자돈에서 근적외석 발광기를 이용한 뇌 혈역학적 변화에 대한 연구 (Near-Infrared Spectroscopy for Monitoring Cerebral Hemodynamics in Hyperbilirubinemia-induced Newborn Piglets)

  • 황종희;최창원;장윤실;박원순
    • Clinical and Experimental Pediatrics
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    • 제48권6호
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    • pp.649-654
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    • 2005
  • 목 적 : 본 연구는 고빌리루빈혈증이 유도된 신생자돈에서 비 침습적인 NIRS을 통한 뇌의 혈역학적 변화에 대해 알아보고자 하였다. 방 법 : 17 마리의 신생자돈을 대상으로 정상 대조군(CG, n=6), 고빌리루빈혈증군(BG, n=7마리), 7-NI를 투여한 고빌리루빈 혈증군(NG, n=4)으로 무작위 구분하였다. 고빌리루빈혈증의 유도는 40 mg/kg의 빌리루빈을 농축괴로 정주한 후 곧 이어 30mg/kg/hr로 4시간 동안 지속 정주하여 혈중 빌리루빈 농도를 20 mg/dL 이상으로 유지하였고 7-NI는 빌리루빈을 농축괴로 투여한 전과 후에 50 mg/kg을 복막투여 하였다. 모든 실험군은 실험 기간 동안 뇌의 혈역학적 변화를 위해 NIRS로 감시하였고 뇌 조직을 적출하여 생화학적인 변화를 관찰하였다. 결 과 : 동맥혈의 base excss, pH, 평균 동맥압은 BG군과 NG군에서 CG군에 비해 유의하게 감소하였다. BG군에서 유의하게 뇌 조직의 $Na^+$, $K^+$-ATPase activity, ATP, PCr은 유의하게 감소하고 conjugated dienes는 유의하게 증가하였으나 NG 군은 이런 이상소견이 유의하게 완화되었다(P<0.05). 뇌 혈역학적 검사상 [$HbO_2$], [HbT], 및 [HbD]는 BG군에서 CG군에 비해 유의하게 감소하였고(P<0.05) NG군은 CG군과 차이가 없었다. 실험 종료시 $ScO_2$는 세 군간에 유의한 차이가 없었다. 결 론 : 고빌리루빈혈증이 유도된 신생자돈에서 뇌의 혈역학적인 변화를 비침습적인 NIRS의 감시를 통해 유용하게 관찰할 수 있었다.

Glutathione S-transferase (GST) 유전자 다형성에 따른 우리나라 젊은 성인의 항산화 상태, DNA 손상 및 지질 양상 (Antioxidative Status, DNA Damage and Lipid Profiles in Korean Young Adults by Glutathione S-Transferase Polymorphisms)

  • 조혜련;이혜진;강명희
    • Journal of Nutrition and Health
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    • 제44권1호
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    • pp.16-28
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    • 2011
  • Oxidative stress leads to the induction of cellular oxidative damage, which may cause adverse modifications of DNA, proteins, and lipids. The production of reactive species during oxidative stress contributes to the pathogenesis of many diseases. Antioxidant defenses can neutralize reactive oxygen species and protect against oxidative damage. The aim of this study was to assess the antioxidant status and the degree of DNA damage in Korean young adults using glutathione s-transferase (GST) polymorphisms. The GSTM1 and GSTT1 genotypes were characterized in 245 healthy young adults by smoking status, and their oxidative DNA damage in lymphocytes and antioxidant status were assessed by GST genotype. General characteristics were investigated by simple questionnaire. From the blood of the subjects, GST genotypes; degree of DNA damage in lymphocytes; the erythrocyte activities of superoxide dismutase, catalase, and glutathione peroxidase; plasma concentrations of total peroxyl radical-trapping potential (TRAP), vitamin C, ${\alpha}$- and ${\gamma}$-tocopherol, ${\alpha}$- and ${\beta}$-carotene and cryptoxanthin, as well as plasma lipid profiles, conjugated diene (CD), GOT, and GPT were analyzed. Of the 245 subjects studied, 23.2% were GSTM1 wild genotypes and 33.4% were GSTT1 wild genotype. No difference in erythrocyte activities of superoxide dismutase, catalase, or glutathione peroxidase, and the plasma TRAP level, CD, GOT, and GPT levels were observed between smokers and non-smokers categorized by GSTM1 or GSTT1 genotype. Plasma levels of ${\alpha}$- and ${\gamma}$-tocopherol increased significantly in smokers with the GSTT1 wild genotype (p < 0.05); however, plasma level of ${\alpha}$-carotene decreased significantly in non-smokers with the GSTM1 wild genotype (p < 0.05). DNA damage assessed by the Comet assay was significantly higher in non-smokers with the GSTM1 genotype; whereas DNA damage was significantly lower in non-smokers with the GSTT1 genotype. Total cholesterol and LDL cholesterol levels were significantly higher in non-smokers with the GSTT1 genotype than those with the GSTT1 wild genotype (p < 0.05). In conclusion, the GSTM1 genotype or the GSTT1 wild genotype in non-smokers aggravated their antioxidant status through DNA damage of lymphocytes; however, the GSTT1 wild type in non-smokers had normal plasma total cholesterol and LDL-cholesterol levels. This finding confirms that GST polymorphisms could be an important determinant of antioxidant status and plasma lipid profiles in non-smoking young adults. Further study is necessary to clarify the antioxidant status and/or lipid profiles of smokers with the GST polymorphism and to conduct a study with significantly more subjects.