油化学
Online ISSN : 1884-2003
ISSN-L : 0513-398X
43 巻, 11 号
選択された号の論文の18件中1~18を表示しています
  • 柏柳 誠, 栗原 堅三
    1994 年 43 巻 11 号 p. 896-905
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    味細胞およびきゅう (嗅) 細胞は, ともに外界からの化学情報を認識し, 識別している。味細胞は, 嗅細胞と比べて比較的受容する化学物質の種類が少ないことと, それらを塩味, 苦味, 酸味, 甘味およびうま (旨) 味の5つの味情報 (5基本味) として識別している点で嗅細胞とは異なっている。一方, 嗅細胞は, 揮発性であればほとんどと言ってよいほど多様な化学物質を認識し, しかもそのにお (匂) いの質の違いを多様に識別している。このため, 両者とも外界の化学情報を受容している細胞であるが, その機構には異なる点が見られる。本小論では, 前半で多くの新しい研究成果が積み重ねられつつある嗅覚系に関する機構を述べ, さらに後半で, 味覚系の機構について考察する。
  • 木村 栄一, 塩谷 光彦
    1994 年 43 巻 11 号 p. 906-913
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    A new breakthrough for zinc (II) enzyme models was achieved with the advent of macrocyclic polyamine zinc (II) complexes. These complexes serve as the best structural as well as functional model for the active centers of zinc (II) enzymes (e.g., carbonic anhydrase, alkaline phosphatase, and alcohol dehydrogenase) and have clearly answered mysteries surrounding the intrinsic properties of zinc (II) in the zinc (II) enzymes. The knowledge newly gained about the properties of zinc (II) has been developed into new supramolecular chemistry, where the zinc (II) enzyme model complexes can recognize thymine and its related derivatives among all the nucleobases in aqueous solution. Here new biochemical functions of the zinc complexes (i.e., inhibition of hybridization of polyribonucleic acids, inhibition of in vitro protein synthesis, inversion of DNA helicity, etc.) are also presented.
  • 有賀 克彦, 国武 豊喜
    1994 年 43 巻 11 号 p. 914-920
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    Various molecular recognition systems were investigated at the air-water interface because a study on molecular recognition in direct contact with bulk water is key to understand molecular recognition in biological systems. Monolayers with synthesized functional groups were found to recognize target molecules, such as ATP, nucleic acid base, sugars, through hydrogen bonding, while the similar recognition is known to be difficult in bulk water phase. The multi-point recognition at the air-water interface was accomplished by using mixed monolayer systems and multi-functional guests. Micellar system of the functional surfactant also showed the recognition ability in aqueous phase, which indicates the concept of specific molecular recognition found at the air-water interface can be extended to other type of interface. The theoretical approach based on quantum chemistry was applied to these systems to figure out the mechanism of molecular recognition at interfaces.
  • 分子鋳型をもつ樹脂の新しい合成法
    前田 瑞夫
    1994 年 43 巻 11 号 p. 921-926
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    Template polymerization has been used to prepare polymeric materials for applications in molecular recognition. However, since the conventional one is conducted in the bulk from monomer, some problems arise ; e.g., slow rebinding kinetics and limited applicability to a water-soluble guest. We designed template polymerization at an oil-water interface. A surfacetemplated resin was prepared by an emulsion polymerization using oleic acid as a host monomer, divinylbenzene (DVB) as a resin matrix-forming monomer, and Cu2+ ion as the target. A phosphate-carrying surface-templated resin can be prepared as well. Another surface imprinting technique was developed based on a surface-carboxylated latex particle, which was swollen with DVB. The surface-mobile groups were reorganized through complexation with the target on the surface and then immobilized by crosslinking of DVB. These two methods can imprint the template structure on a resin surface, resulting in the rapid, reversible and unusually strong complexation with the target.
  • 小宮山 真, 八代 盛夫
    1994 年 43 巻 11 号 p. 927-932
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    Lanthanide ions are remarkably active for the hydrolysis of phosphodiester linkages in DNA and RNA. The magnitudes of acceleration range from 106 to 1012 fold. With the use of Ce (IV) ion (0.01 mol dm-3), the phosphodiester linkages in linear DNAs are hydrolyzed for the first time non-enzymatically (half-life 3.6 h at pH 7.2, 50 °C).
    Furthermore, the linkages in RNA are efficiently hydrolyzed at pH 7.2, 30 °C with the halflife 3.6 min by Lu (III). Non-lanthanide metal ions show virtually no catalysis : the superb catalysis is specific for lanthanide ions. The first site selective hydrolytic cleavage of DNA has been accomplished by artificial enzymes constituting of the cerium (IV) -iminodiacetate complex (an active site) and DNA which is complementary to the target DNA (the sequence recognition site). These results have opened the way to construction of artificial nucleases and ribonucleases.
  • 宍戸 昌彦
    1994 年 43 巻 11 号 p. 933-940
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    Monoclonal antibodies were raised against nonnatural amino acids carrying aromatic groups, such as pyrenyl group and trans-azobenzene group. The anti-pyrenyl antibody was used to investigate fluorescence behavior of pyrenyl groups bound to the antibody. The hapten was found to be bound not very tightly deep inside the binding site. The anti-azobenzene antibody was found to bind only the trans form of azobenzene group. By using this unique property, photoswitching of an enzyme reaction and photocontrol of the antibody binding to solid surfaces were demonstrated.
  • 大久保 捷敏
    1994 年 43 巻 11 号 p. 941-952
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    The efficiency of catalyst molecular helicity for the asymmetrically amplified photocatalysis was investigated with newly designed ruthenium (II) complexes, M (C3) -Δ- [Ru (Menbpy) 3] 2+ (1 a ; MenbPY=4, 4'-di [(1 R, 2 S. 5 R) - (-) -menthoxycarbony1] -2, 2'-bipyridine), M (C3) -Δ or P (C3) -Λ- [Ru (R or S-PhEtbpy) 3] 2+ (2a or 2b ; R or S-PhEtbpy=4, 4'-di [(R) - (+) {or (S) - (-)} -1-phenylethylaminocarbony1] -2, 2'-bipyridine) or P (C3) -Δ- [Ru (bpy) 3] (3a), in the asymmetric resolution, synthesis, or isomerization of P (C3) -Δ and M (C3) -Λ- [Co (acac) 3] (4a and 4b ; Hacac=pentene-2, 4-dione), where P (C3) or M (C3) indicates a plus (clockwise) or minus (counterclockwise) helical arrangement along the C3 symmetry axis, respectively.
    The most efficient molecular recognition in the asymmetrically amplified photocatalysis was resulted from the catalytic ability of the la helical complex possessing effective molecular extent of the helicity in the direction of C3 axis along which racemic 4a-b, reaction products [Co (acac) 2 (H2O) 2] /acac-, or five-coordinate intermediate [Co (acac) 2 (acac-)] interacted with 1a to accumulate M (C3) -4b.
    The mode of asymmetric interaction between the photocatalyst and the reactant was well explained by the molecular mechanics (MM) and interactive frontier orbital (IFO) treatments.
  • 畑中 研一
    1994 年 43 巻 11 号 p. 953-959
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    Sulfated polysaccharides show a lot of biological activities. There are two kinds of molecules which recognize sulfated polysaccharides. Non-specific recognition of sulfated polysaccharide depends on the degree of sulfation and the molecular weight of the sulfated polysaccharide. On the other hand, the chemical structure of sulfated polysaccharide affects on the specific recognition. In this review, recognition of sulfated polysaccharides is reported, taking the cases of anticoagulant activity, activation of basic fibroblast growth factor, and anti-HIV activity.
    Recognition of neutral polysaccharide is relatively weak but more specific. A synthetic approach to a branched polysaccharide, which shows hypoglycaemic activities, is also reviewed.
  • 糖鎖を認識信号とする生体機能材料
    小林 一清
    1994 年 43 巻 11 号 p. 960-967
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    Well-defined polymers having pendant oligosaccharide chains as the recognition signals, termed “artificial glycoconjugate polymers”, are described. The first part of this review treats the applications of oligosaccharide-substituted polystyrenes to cell-specific biomedical materials using the oligosaccharides as the key participants in cell-substratum recognitions. Lactose-carrying polystyrene abbreviated as PVLA is a useful substratum for culture of parenchymal liver cells (hepatocytes). Owing to the hydrophilic-hydrophobic structure, PVLA formed compactpacked (super molecular) conformations in water and were adsorbed on the surface of polystyrene culture dishes. As the result, highly-concentrated galactose signals protruded from the material surfaces to interact strongly with asialoglycoprotein receptors of the cell surfaces. Cell-culture systems using the strong interactions between pancreatic cells and maltose-carrying polystyrene and between erythrocytes and a reducing glucose-carrying polystyrene are also of interest.
    The second part is concerned with our synthetic approaches to four different types of artificial glycoconjugate polymers having highly-concentrated carbohydrate signals. (1) Chemoenzymatic synthesis of polyacrylamide derivatives, especially, having β-linked N-acetyllactosamine moiety, a major component of oligosaccharide chains of glycoproteins. (2) Multi-branched graft copolymers. (3) Branched (1→6) -α-mannan polysaccharide having pendant α-mannose units. (4) Oligosaccharide-substiuted poly (γ-glutamate).
  • 上杉 志成, 杉浦 幸雄
    1994 年 43 巻 11 号 p. 968-974
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    Esperamicin and calicheamicin are among the most prominent members of enediyne antibiotics. Combining highly unusual molecular structures, potent biological activities, and fascinating modes of action, these DNA-cleaving compounds elicited extensive research activities in chemistry, biology, and medicine. This review weights the oligo (purine/pyrimidine) recognition by esperamicin and calicheamicin. We begin by consideration of the experimental approaches that have been used to provide insights into the recognition process. Next we summarize the recent interpretations of the sources of the specificity to oligo (purine/pyrimidine) sequences.
  • 高木 康臣, 澤田 愼矢, 吉成 幸一, 多比良 和誠
    1994 年 43 巻 11 号 p. 975-983
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    The structure of a hammerhead ribozyme does not change significantly in the presence or absence of Mg2+ ions, an indication that the role of Mg2+ ions is catalytic rather than structural. Accordingly, kinetics and molecular orbital calculations indicate that ribozymes are metalloenzymes. Kinetic analysis supports the idea that an important part of the binding energy (reflected in Kd) is utilized to provide the driving force for catalysis, so that the observed binding energy (Km reflected in) represents only what is left over after this utilization. It is also possible to produce nuclease-resistant ribozymes.
  • 小島 直也
    1994 年 43 巻 11 号 p. 984-993
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    Mechanisms of cell-cell interaction and the molecules involved in this event are characterized by a high degree of redundancy. Since all living cells are characterized by highly glycosylated cell surface, cell surface carbohydrate chains are thought to play some roles for cell-cell interaction. At least three classes of cell-cell interaction systems are currently known : (1) protein-protein interaction, (2) carbohydrate-protein interaction, and (3) carbohydrate-carbohydrate interaction. In this article, I described that the mechanisms of carbohydrate-carbohydrate interaction and selectin-carbohydrate interaction. Since both interactions are rather weaker but faster than protein-protein interaction, cell-cell interaction is triggered by such carbohydrate-depen-dent mechanisms. Several lines of studies indicate that carbohydrate chains should be formed the carbohydrate-cluster on cell surface for occurring carbohydrate-dependent interaction. It has been known that glycosphingolipids or mucin-type oligosaccharides easily form carbohydrate cluster. Thus, such clustered carbohydrates on cell surface, but not a single carbohydrate chain, may play a crucial role for cell-cell interaction.
  • 横山 和正, 上田 泰生
    1994 年 43 巻 11 号 p. 994-1000
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    The present situation and the future of lipid microsphere (LM) as a drug carrier are reviewed. LM has been used as a parenteral nutrient agent for nearly 50 years and already evaluated to be safe. Dexamethason palmitate and alprostadil (PGE1) encapsulated in LM are successful examples with enhanced efficacy and specific distribution. These LMs are eliminated from blood stream very fast : Reticuroendotherial system and lipoprotein lipase are considered to be major factors affecting plasma clearance. If we have different kind of LM with long plasma half-life, LM could have wide application as a drug carrier.
  • 触媒活性に及ぼすリン脂質 (反応場) の影響
    大勝 靖一, 末吉 孝
    1994 年 43 巻 11 号 p. 1001-1006
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    反応基質に親水性から疎水性の数種のアミノ酸エステルを用い, 糖脂質触媒の活性に及ぼすリン脂質 (反応場) の影響を検討した。その結果, ホスファチジルコリンの添加では触媒活性を向上させ, ホスファチジルグリセリンは逆に大きく活性を低下させた。特に, ホスファチジルコリンにおいては, その添加にともなって糖脂質がα-キモトリプシン類似の挙動を示すことがわかった。
  • 黒澤 茂, 加茂 直樹, 有村 隆志, 関屋 章, 堀川 幸稔, 栗田 亨, 田坂 茂, 稲垣 訓宏
    1994 年 43 巻 11 号 p. 1007-1010
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    ミリポアフィルター上にスルホン酸基を固定した含フッ素膜をペルフルオロベンゼンとSO2の混合系によりプラズマ重合法で合成した。ジオクチルフタレートを含浸した重合膜電極は10-2~10-5Mのテトラフェニルホスホニウムに対してNernst式に従う応答を示した。
  • 河合 武司, 五邊 正男, 佐藤 幸哉, 今野 紀二郎, 北原 文雄
    1994 年 43 巻 11 号 p. 1011-1016
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    By the polymerization of acrylamide initiated with potassium peroxodisulfate (KPS) in water solubilized by Aerosol OT (AOT) reversed micelles, of polyacrylamide particles became linked to a microgel by N, N'-methylenebisacrylamide (MBAAm). Magnetic microgel particles containing magnetite particles were prepared based on the relation of [water] to [AOT] (Rω) at 60°C. The influence of Rω, [MBAAm], and [magnetite] on particle size was examined.
    The following results were obteined :
    1) Monodisperse and spherical polyacrylamide particles were produced in the systems of Rω=15 and 20, but in the systems of Rω=25 and 30, they become bimodal. Particle size increased with Rω. These results are discussed in relation to the solubilized states of water in reversed micelle interion.
    2) Monodisperse and spherical microgel particles were obtained and their size was noted to increased with Rω and [MBAAm].
    3) Spherical magnetic microgel particles including 50 % of the initial [Fe3O4] were obtained and their size was noted to increase with Rω and [MBAAm], but not to be affected by [Fe3O4]. In these systems, the rate of polymerization was enhanced by SO42- radical produced through redox reaction of Fe2+ of magnetite with S2O82- of KPS.
  • 酸化防止力に影響を及ぼす要因
    磯部 次男, 清野 肇
    1994 年 43 巻 11 号 p. 1017-1021
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    The authors previously reported 2-alkyl-2-methyl-1, 3-dioxaindans to possess antioxidative activity toward lards, and alkyl groups at the 2-position of these compounds to be a determining factor of activity. The introduction of the t-butyl group into the aromatic ring in these compounds resulted in high antioxidative activity.
    2, 2-Dialkyl-1, 3-dioxaindans were synthesized for comparison of the effects of the alkyl group at the 2-position on antioxidative activity. Methyl, t-butyl or amino group was introduced into the aromatic rings of these compounds. Based on the antioxidative activity of these compounds, assessment was made of the influence of the functional groups on the aromatic ring. These groups were found to have greater antioxidative effect than that of the alkyl group at the 2-position.
  • 牛草 寿昭, 丸山 武紀, 新谷 〓
    1994 年 43 巻 11 号 p. 1022-1026
    発行日: 1994/11/20
    公開日: 2009/10/16
    ジャーナル フリー
    By programmed thermogravimetry (TG), weight loss of 8 synthetic antioxidants was examined, and thermostability was determined from initial temperatures based on TG and decomposition time at 5 % by isothermal TG. Antioxidant content in residual substances was determined at 25 % weight loss by TG. The results obtained are summarized as follow :
    1) For programmed TG, curves for synthetic antioxidants showed characteristic weight loss patterns depending on the type of antioxidant. Weight loss patterns were not influenced by atmospheric gas used (air and nitrogen).
    2) At 25 % weight loss by TG, phenolic antioxidant content in residual sabustances exceeded 90 % in both gases. Gallate content was less than that observed for phenolicis.
    3) Synthetic antioxidant thermostability increased in the order of NDGA>DG>OG>PG>THBP>TBHQ>BHA>BHT as determined from TG data.
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