• Title/Summary/Keyword: Polyenes

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Non-Linear Optical Properties of Polyacetylene Using Ab Initio Time-Dependent Hartree-Fock Theory (폴리 아세틸렌의 비선형 광학성질에 대한 양자 역학적 고찰)

  • Kim, Seung Joon
    • Journal of the Korean Chemical Society
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    • v.40 no.5
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    • pp.317-326
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    • 1996
  • The frequency dependent longitudinal polarizabilities ${\alpha}zz(\omega)$ and the second hyper-polarizabilities ${\gamma}zzzz(\omega)$ of the linear polyenes, $C_4H_6\;to\;C_{30}H_{32}$, have been evaluated using the ab initio time-dependent coupled perturbed Hartree-Fock (TDCPHF) theory with the 6-31G basis set. The ratios of the dynamic properties to the static values have been examined to illustrate the relative dispersion effect and extrapolated to the infinite polymer limit. Also the effect of interchain interaction for linear and nonlinear optical properties has been investigated for $C_4H_6$ and the theoretical discussion has been described to overcome the limitation of ab initio TDHF method in the resonance region.

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Effects of Drying Conditions on Lipid Oxidation and Patty acid Compositions of Large Anchovy (대멸치의 지질산화 및 지방산 조성의 변화에 미치는 건조조건의 영향)

  • Cho, Young-Je;Shim, Kil-Bo;Kim, Tae-Jin;Kang, Su-Tae;Lee, Ho-Soo;Choi, Young-Jin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.3
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    • pp.192-197
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    • 2000
  • To develop plain dried products of large anchovy, Engraulis japonica, lipid oxidation during drying of large anchovy and optimal drying condition were investigated. The moisture contents of large anchovy on 7 hrs dryness were $ 9.0{\%},\;34.0{\%},\;38.0{\%} and\;38.8{\%}\;in\;60^{\circ}C$ hot-air drying (wind velocity, 1.4m/sec), $40^{\circ}C$ hot-air drying (wind velocity, 1.4 m/sec), sun drying($30{\pm}5^{\circ}C$) and $20^{\circ}C$ cold-air drying (wind velocity, 3.1 m/sec), respectively. The cold-air drying depressed remarkably the lipid oxidation of large anchovy during drying, resulting from AV, POV, COV and the formation of browning pigment. The fatty acid composition of large anchovy was $35.8{\%} in saturates, 20.0{\%} in monoenes and 44.2{\%}$ in polyenes. Saturates and monoenes were increased in proportion to the increase of drying time, while polyenes were decreased. The contents of 20 : 5 and 22 : 6 of polyenes were decreased remarkably in proportion to the progress of lipid oxidation, while 14 : 0, 16 : 0, 16 : 1 and 18 : 1 of saturates and monoenes were increased. The changes in fatty acid compositions by drying conditions were remarkably clarified in sun drying, followed by $60^{\circ}C$ hot-air drying $40^{\circ}C$ hot-air drying and $20^{\circ}C$ cold-air drying in order.

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Seasonal Variation in Body Composition in Boleophthalmus pectinirostris Collected from Gangjin, Jeonnam, Korea (전남 강진산 짱뚱어(Boleophthalmus pectinirostris) 체성분의 계절변화)

  • Jung, Bok-Mi;Jeong, Soon-Jae;Han, Kyeong-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.50 no.3
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    • pp.270-277
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    • 2017
  • This study was carried out to investigate seasonal changes in body composition in Boleophthalmus pectinirostris in Korea. B. pectinirostris collected in Gangjin, Jeonnam, consisted of 58.7-75.8% moisture content, 16.1-17.6% protein, 0.8-3.4% crude lipids, and 1.3-3.6% crude ash. Livers consisted of 15-17% moisture content, 14.0-16.8% crude protein, 34.4-71.2% crude lipids, and 0.5-1.2% crude ash. Calcium, iron, potassium, etc., content in B. pectinirostris muscle averaged 267.5-599.8 mg/100 g, 1.98-28.3 mg, 160.7-327.9 mg, 20.6-60.2 mg, 0.4-2.2 mg, 0.23-0.46 mg, 66.5-192.9 mg, and 1.32-3.8 mg, respectively. (Please clarify: the list of measured values must correspond directly with what was measured, not just "etc.") The major amino acids in B. pectinirostris muscle, in proportional order, were glutamic acid, isoleucine, and leucine; whereas the major amino acids in the liver were glutamic acid, lysine, aspartic acid, and leucine. The major saturated fatty acids in the muscle were palmitic acid (15-19%) and stearic acid (8-11%). The major monoenes and polyenes were palmitoleic acid (C16:1) and oleic acid (C18:1), and EPA and DHA, respectively. The major saturated fatty acids and polyenes in the liver were the same as in muscle, but the monoenes were palmitoleic acid (C16:1) and cis-10-hepta-decenoic acid (C17:1). Seasonal changes in B. pectinirostris body composition may be attributable to differential accumulation of fat and nutrients in comparison to the spawning and hibernation period.

Studies on the Lipid Components in Sweetfish from Korea-1 Comparison of the contents of total lipid components (한국산 은어의 지질성분에 관한 연구-1 총지질성분의 비교)

  • MOON Soo-Kyung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.26 no.3
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    • pp.235-240
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    • 1993
  • This study was carried out to compare the difference of proximate composition and total lipid components by size and various tissues in sweetfish(Plecoglossus altivelis). Lipid contents of the small and large sweetfish in viscera were $43.2\%\;and\;52.8\%$, respectively. Total lipid contents of the small and large sweetfish were consisted of $3.84{\sim}46.90g/100g$ neutral lipid, $0.86{\sim}4.38g/100g$ phospholipid, respectively. In fatty acid compositions of total lipid, sweetfish showed higher content in saturates such as 16:0, 18:0($43.78{\sim}48.29\%$), and lower content in polyenes such as 18:2n-6, 22:6n-3($13.13{\sim}17.10\%$), and the large sweetfish was somewhat higher in ratio of polyenes compared with the small one. The major fatty acids were 16:0, 18:1n-9, 16:1n-7, 18:2n-6, 22:6n-3, 18:0 and 14:0, in order.

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Collective Electronic Oscillator Method: Application to Conjugated Organic Molecules

  • Lee, Jin-Yong
    • Bulletin of the Korean Chemical Society
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    • v.24 no.6
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    • pp.780-784
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    • 2003
  • The collective electronic oscillator (CEO) method was developed by Mukamel and collaborators.[Phys. Rev. Lett. 1992, 69, 65; Science 1997, 277, 781] Recently Ⅰ have extended the CEO method to obtain the frequency dependent optical properties with all the contributing components. The brief introduction of the CEO fomalism and its recent applications to linear absorption and two-photon absorption (TPA) of conjugated organic molecules will be discussed. The size scaling of optical properties of polyenes and polyynes have studied by ab initio calculations, and this result is consistent with the coherence length of the time dependent densities to first ($ρ^(1)$) and second order ($ρ^(2)$) in the electric field obtained from the CEO method.

Food Components of Coho Salmon and Rainbowtrout (은연어와 무지개 송어의 식품성분)

  • 김경삼;최영준
    • The Korean Journal of Food And Nutrition
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    • v.6 no.2
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    • pp.73-80
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    • 1993
  • In order to examine food components of coho salmon and rainbow-trout, We analyzed the composition of protein, amino acids and total lipids. The coho salmon muscle contained about 19.3% of protein with the composition of 29.9% in sarcoplasmic protein, 56.3oA in myofibrillar protein 12.5% alkali soluble protein and 2.6% in stroma. Those of rainbow-trout contained 34.1%, 56.4%, 8.3% and 2.9%, respectively. The sarcoplasmic and myofibrillar protein were composed of 13 subunits in coho salmon, and 16 and 15 subunits in rainbow-trout. Judging from the contents of essential amino acids, both muscle proteins were complete proteins. The most remarkable feature of free amino acids was that a large amount of dipeptide anserine was present with fairly lower levels of 1 methyl histidine, taurine, histidine, alanine and glycine in both muscle extracts. The total fatty acids of coho salmon was composed of 31.49% polyenes, 43.79% monoenes and 24.73% saturates. The composition of total fatty acid of coho salmon muscle was not different from that of rainbow-trout muscle.

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Isolation of Cryptic Polyene Hydroxylase Gene in Rare Actinomycetes via Polyene-specific Degenerate PCR. (Polyene 특이적인 PCR에 의한 희소 방선균 유래 Cryptic Polyene Hydroxylase 유전자의 분리)

  • 박현주;명지선;박남실;한규범;김상년;김응수
    • Microbiology and Biotechnology Letters
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    • v.32 no.3
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    • pp.282-285
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    • 2004
  • The polyene antibiotics including nystatin, pimaricin, amphotericin and candicidin are a family of most promising antifungal polyketide compounds, typically produced by rare actinomycetes species. The biosynthetic gene clusters for these polyenes have been previously investigated, revealing the presence of highly homologous biosynthetic genes among polyene-producers such as polyketide synthase (PKS) and cytochrome P450 hydroxylase (CYP) genes. Based on amino acid sequence alignment among actinomycetes CYP genes, the highly-conserved regions specific for only polyene CYP genes were identified and chosen for degenerate PCR primers, followed by the PCR-screening with various actinomycetes genomic DNAs. Among tested several polyene non-producing actinomycetes strains, Pseudonorcardia autotrophica strain was selected based on the presence of PCR product with polyene-specific CYP gene primers, and then confirmed to contain a cryptic novel polyene hydroxylase gene in the chromosome. These results suggest that the polyene-specific hydroxylase gene PCR should be an efficient way of screening and isolating potentially-valuable cryptic polyene antibiotic biosynthetic genes from various microorganisms including rare actinomycetes.

Excited-State Dynamics of Carotenoids Studied by Femtosecond Transient Absorption Spectroscopy

  • Lee, Ingu;Lee, Sebok;Pang, Yoonsoo
    • Bulletin of the Korean Chemical Society
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    • v.35 no.3
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    • pp.851-857
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    • 2014
  • Carotenoids, natural antenna pigments in photosynthesis share a symmetric backbone of conjugated polyenes. Contrary to the symmetric and almost planar geometries of carotenoids, excited state structure and dynamics of carotenoids are exceedingly complex. In this paper, recent infrared and visible transient absorption measurements and excitation dependent dynamics of 8'-apo-${\beta}$-caroten-8'-al and 7',7'-dicyano-7'-apo-${\beta}$-carotene will be reviewed. The recent visible transient absorption measurements of 8'-apo-${\beta}$-caroten-8'-al in polar and nonpolar solvents will also be introduced to emphasize the complex excited-state dynamics and unsolved problems in the $S_2$ and $S_1$ excited states.

PHOTOISOMERIZATION STUDIES OF SUBSTITUTED DIPHENYLBUTADIENES: ROLE OF POLARIZED EXCITED STATES IN THE PHOTOPROCESSES OF $\alpha,\omega$-DIPHENYLPOLYENES

  • Singh, A.K.;Krishna, T.S.R.
    • Journal of Photoscience
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    • v.5 no.2
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    • pp.47-51
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    • 1998
  • Direct irradiation of 1Z,3E-1-cyano-1,4-diphenylbutadiene (2) and 1Z,3E-1-cyano-3-methyl-1,4-diphenylbutadiene (3) in organic solvents viz. n-hexane, methanol and acetonitrile results in preferential isomerization of the double bond substituted with cyano group via one-photon-one-bond isomerization process. The quantum efficiency of the isomerization of 3 is more than 2 in all the three solvents. Photoproducts of 2 and 3 (viz. 2a, 2b, 3a, 3b) also exhibited similar photoisomerization trends. The results are discussed in terms of the effects of substituents on the potential energy surface of the excited singlet states of $\alpha$,$\omega$-diphenylpolyenes, and the role of zwitterionic dipolar species in the photoisomerization process of linearly conjugated C=C polyenes is highlighted.

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Fatty acid Composition of Miyeok(undaria pinnatifida) and Pare (Enteromorpha compressa) (미역과 파래의 지방산 조성)

  • 홍재식;권영주;김영희;김명곤;박일웅;강귀환
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.20 no.4
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    • pp.376-380
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    • 1991
  • The contents of total lipids from Korean marine benthic algae Miyeok(Undaria pinnatifida) and Pare(Enteromorpha compressa)were 1.8% and 0.7% on the dry basis, respectively. They were fractionated by silicic acid column chromatography and identified by gae liquid chromatography. The ratios of neutral lipids, glycolipids and phospholipids in total lipids were 3.5 : 74.1 : 22.4 in Miyeok and 33.1 : 48.4 : 18.5 in Pare. Total fatty acids in Miyeok and Pare were composed of 28.5 and 33.2% of saturates, 9.8 and 10.8% of monoenes, 61.7 and 56.0% of polyenes, respectively and the polyunsaturated acid was the most predominent component. $\omega$-3 polyunsaturated fatty acids were C18:4(15.9 and 17.1%) and C20:5(10.6 and 6.0%).

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