オリーブに含まれるオリーブアナアキゾウムシ摂食刺激物質β-sitostery-D-glucoside

The olive weevil [Dyscerus perforatus (ROELOFS); Coleopetera; Curculionidae] is a native species in Japan and now the most serious pest of the olive trees. Originally, this weevil seemed to colonise Ligustrum japonicum Thumb. and L. obtusifolium Sieb. et Zucc, both of which belong to the same oleacea family as olive. However, when olive trees were introduced to Japan in 1908, the weevils immediately attacked the plants and soon preferred them to the former hosts. Unlike in the former hosts, where the weevils live in a low population density, it is extraordinary high in the case of olive trees and the subsequent assault becomes seriously damaging for the host plant. During the course of our study on the relationship between olive trees and olive weevils, we came to be interested in the possible chemical constituents that are responsible for host selection and attraction of the olive weevil to this plant. Previously, we reported that a secoiridoid gluconside, oleuropein, and some lignans, (-)-olivil and (+)-l-acetoxypinoresinol, from the olive tree stimulated the feeding habit of the weevil. In this study, we found a steroidal glucoside as another feeding stimulant component in the olive tree. Here, we describe the isolation, characterization and activity of this feeding stimulant.オリーブアナアキゾウムシは，モクセイ科のオリーブに多数寄生し甚大な被害を与えるため，オリーブ栽培上の深刻な問題となっている．我々は，これまでオリーブのメタノール抽出物から，オリーブアナアキゾウムシの摂食刺激成分として，雌雄に活性を示すセコイリドイド配糖体1種と，雌に特異的に活性を持つ2種のリグナン類を得た．さらに今回，同じメタノール抽出物から，活性物質としてステロイド配糖体であるβ-sitosteryl-D-glucosideを得た．この成分は雌雄に対してほぼ同等の摂食刺激活性を示した

ケニア産キク科薬用植物Vernonia hindiiに含まれる生物活性物質

A novel stigmastane-type steroid glucoside glucoside has been isolated from the aerial parts of Vernonia hindii.The structure was elucidated by spectroscopic methods.The compound exhibitewd lettuce seedling growth inhibitory activity.熱帯・砂漠など特殊な環境に自生する植物には、生物活性2次代謝物質を含むものが多く、古くから民間伝承薬や天然殺虫剤として使用されてきた。しかし、まだ十分に調査・研究されていない植物も残されている。本研究では、ケニアに自生するキク科薬物植物のVernonia hindiiに含まれる活性物質の単離と構造解明を行い、その生物活性を調べた。植物生長制御試験を指標としてV . hindiiのメタノール抽出物を文画・精製した結果、新規の化学構造をもつ植物生長抑制物質を単離した。さらに、種々の分析機器を用いて化学構造を解析し、stigmastan型のステロイド配糖体であると決定した。この化合物は100μg / discでコントロールと比べ、24％まっでレタスの生長を抑制した

多価不飽和脂肪酸を２位に結合するホスファチジルコリンの炭素アナローグの合成

Carbon analogues of Phosphatidylcholines having linoleic or arachidonic acid at the 2-position were synthesized. The synthetic route involves conversion of the polyunsaturated fatty acid iodination. The derivatives were converted to diols by LiAIH4 reduction and submitted to lipase-catalyzed monostearoylation in isopropylether. The mono-ester was converted to phoshatidylcholines by the usual phosphodiester synthesis.自然界に広く存在するホスフォリパーゼA2はグリセロリン脂質の2位のエステル結合を選択的に切断する酵素であり,消化,アラキドン酸カスケードの起動,リン脂質過酸化物の代謝等,生理作用に広く関わっている。本研究ではホスフォリパーゼA2の基質ミメテイックとしてホスファチジルコリンの2位エステル結合が炭素-炭素結合に置き換わった化合物をアラキドン酸とステアリン酸を出発原料としてリパーゼ触媒によるアシル化反応及び有機化学反応によって合成した

Reactions of 1-stearoyl-2-(13'-oxo-9',11'-tridecadienoyl)-sn-glycero-3-phosphocholine with amino acids and peptides and its differential generation from hydroperoxides of 1-stearoyl-2-&alph;-linolenoyl-sn -glycero-3-phosphocholine and

Phosphatidylcholines (PCs) bearing various kinds of aldehydic acyl chains at the sn-2 position have been detected in atherosclerotic tissues. However, 1-acyl-2-(13'-oxo-9',11'-tridecadienoyl)-sn-glycero-3-phosphocholine and other a,b,g,d-unsaturated aldehyde PCs have not. To determine whether this might be due to their high chemical reactivity with biomolecules, we investigated the reactions of 1-stearoyl-2-(13'-oxo-9',11'-tridecadienoyl)-sn-glycero-3-phosphocholine (OTDA-PC, where OTDA refers to the oxo-tridecadienoyl moiety) with nucleophilic amino acids and peptides by means of electrospray mass spectroscopy. OTDA-PC formed Michael adducts with lysine, arginine, histidine, hippuryl lysine and hippuryl arginine, but was surprisingly unreactive with cysteine or glutathione. When 1-stearoyl-2-(13'-hydroperoxy-9'Z,11'E,15'Z-octadecatrienoyl)-sn-glycero-3-phosphocholine (PC-LNA-OOH, where LNA-OOH denotes the linolenic acid hydroperoxide moiety)　was decomposed in the presence of the reactive lysine, OTDA-PC was still detected as a major product. However, OTDA-PC could not be detected when 1-stearoyl-2-(13'-hydroperoxy-9'Z,11'E-octadecadienoyl)-sn-glycero-3-phosphocholine (PC-LA-OOH, where LA-OOH refers to linoleic acid hydroperoxide) was decomposed in the presence or absence of lysine.  Since linoleic acid is the major polyunsaturated fatty acid in atherosclerotic tissues, these results indicate that formation of OTDA-PC in only minor amounts in such tissues may explain its not having been detected in them. Surprisingly, 1-stearoyl-2-(9'-oxononanoyl)-sn-glycero-3-phosphocholine was the major aldehydic product of the decomposition of PC-LA-OOH under anaerobic conditions. KEY WORDS: Lipid oxidation, Bioactive phospholipid aldehydes (core aldehydes), Michael addition  Bull. Chem. Soc. Ethiop. 2008, 22(2), 269-276.&#160

Morphology-Induced Collective Behaviors: Dynamic Pattern Formation in Water-Floating Elements

Complex systems involving many interacting elements often organize into patterns. Two types of pattern formation can be distinguished, static and dynamic. Static pattern formation means that the resulting structure constitutes a thermodynamic equilibrium whose pattern formation can be understood in terms of the minimization of free energy, while dynamic pattern formation indicates that the system is permanently dissipating energy and not in equilibrium. In this paper, we report experimental results showing that the morphology of elements plays a significant role in dynamic pattern formation. We prepared three different shapes of elements (circles, squares, and triangles) floating in a water-filled container, in which each of the shapes has two types: active elements that were capable of self-agitation with vibration motors, and passive elements that were mere floating tiles. The system was purely decentralized: that is, elements interacted locally, and subsequently elicited global patterns in a process called self-organized segregation. We showed that, according to the morphology of the selected elements, a different type of segregation occurs. Also, we quantitatively characterized both the local interaction regime and the resulting global behavior for each type of segregation by means of information theoretic quantities, and showed the difference for each case in detail, while offering speculation on the mechanism causing this phenomenon

Sn-1位に多価不飽和脂肪酸を結合する2-0-methoxyethoxymethylglycerolの立体配置決定

A correlation of optical rotation, optical purity and configuration of the asymmetric center was done for 2-0-methoxyethoxymethylglycerol bearing polyunsaturated fatty acyl group at sn-1 position. This compound was enzymatically prepared and is an important starting material for the syntheses of optical active glycerophospholipids naving polyunwaturated fatty acyl groups.自然界に広く存在し，重要な生理機能を担っている多価不飽和脂肪酸結合リン脂質の化学的合成に必要な出発原料としての2-0-methoxyethoxymethylglycerolの立体配置と光学純度を，立体配置・光学純度既知の物質に化学的に誘導し，それらの比旋光度をお互いに比較する事により決定した

Gravitational fermion creation during an anisotropic phase of cosmological expansion

The free Dirac equation is solved in a Bianchi Type I space-time, which represents a homogeneous but anisotropic universe, to show the creation of fermionic particles. It is found that unlike in the isotropic case, massless fermion production is possible. An estimate of the energy density of massless particles created during an early anisotropic phase of cosmological expansion is shown to cause substantial back-reaction on the gravitational field. The potential relevance to dark matter particle production, primordial magnetogenesis, and early universe cosmology is discussed briefly.Comment: Accepted for publication in Physical Review

Methyl 13-hydroperoxyoctadecadienoateの分解に対する蔬菜類の抑制効果

The preventive actions of some vegetables on the degradation of 13-hydroperocxyoctadecadienoate were investigated.Among these,kindly bean extract prevented the degradation of the hydroperoxide at about 60% followed by green pepper,cucumber,spinach pumpkin,mushroom,carrot,and shungiku to defferent degrees.不飽和脂質の酸化防止に関する研究は今日なお活発に行われており、その食品学的重要性と問題の難しさには変わり無い。自動酸化によって生成した過酸化物は極めて容易に分解し、その分解生成物は食品の重大な劣化を招き、健康を害することは良く知られている。本研究ではMethly 13-hydroperoxyoctadecadienoateの分解の抑制について検討したところ、ある種の蔬菜のクロロホルム―メタノール抽出物に分解阻止効果があることが明らかになった。例えばいんげん豆抽出物は過酸化物に対して、60℃、96時間の過熱においても約60%の分解抑制作用を示すことが判明した

ケニヤ産植物、Psiadia punctulata に含まれる植物生長調節物質

Compounds having plant growth regulatory effect were found in Kenyan Psiadia punctulata, and two flavones,5-hydroxy-7,2',3',4',5'-pentamethoxyflavone(1) and 5,3'-dihydroxy-7,2',4',5'-tetramethoxyflavone(2) were isolated and identified as the activ constituents.植物の生長を制御する物質を広く天然に求めることは、より安全で有効な農薬およびその関連物質を開発するための重要な課題である。本研究では、レタス幼苗の生長に対する調節物質の探索をケニヤ産植物Psiadia punctulata について行った。その結果、同植物のメタノール抽出物より、5-hydroxy-7,2',3',4',5'-pentamethoxyflavone 及び　5,3'-dihydroxy-7,2',4',5'-tetramethoxyflavone を調整物質として単離した。前者は、根や胚軸の長さを130％まで増加させたが、全体の重量はほぼ80％にまで減少させた。一方、後者も同様の活性パターンを示し、根を140％伸張させ植物体重量を58％まで減少させるという興味ある現象が観察された。

Isolation and Purification of Nocardamine from the Validamycin Producer

An antibacterial active against P. mirabilis was isolated from the culture of Streptomyces hygroscopicus subsp. limoneus, validamycin producer. The antibiotic was found to be produced with a non-validamycin producing condition. The antibiotic was identified as nocardamine with the analytical data, IR, 1H-NMR and 13C-NMR spectra.Streptomyces hygroscopicus subsp. limoneus はバリダマイシン生成菌として知られているが、その抗カビ物質以外に抗細菌性抗生物質を生成することは知られていない。われわれはその微生物がバリダマイシン非生成条件において生成する抗細菌性抗生物質を見出そうと試みた。その結果、グラム陰性細菌に活性を示す抗生物質EO-3を得たのでこれを分離・精製してノカルダミンと同定した。本報告では本抗生物質の培養条件、抗菌スペクトル、精製および同定方法について述べる。尚、この研究は平成6年度から8年度までの3年間に亙る岡山大学学内特定研究『特殊環境生物の機能開発と物質生産への応用』を分担して行ったものである