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| 融点 | 483 °C (decomp) | | 比旋光度 | 198 º | | 屈折率 | 185 ° (C=6, H2O) | | 貯蔵温度 | 2-8°C | | 溶解性 | H2O: soluble50mg/mL, clear to very slightly hazy, colorless to faintly yellow | | 外見 | Solid | | 色 | White to slightly off-white | | PH | 2 - 10 | | 水溶解度 | Soluble in water, dimethyl sulfoxide, ethylene glycol and glycerol. | | Merck | 14,2948 | | 安定性： | Stable. Keep dry. Incompatible with strong oxidizing agents. | | LogP | -4.259 (est) | | EPAの化学物質情報 | Dextran (9004-54-0) |
| | デキストラン75 Usage And Synthesis |
| 外観 | 白色の粉末 | | 定義 | 本品は、デンプンに酵素を作用させて得られる多分岐環状ポリサッカライドであり、500~2000のグルコース単位からなる。 | | 溶解性 | 水に可溶, エタノール, エステルに不溶。水に溶け、エタノールにほとんど溶けない。 | | 解説 | デキストラン,(α1→6)グルカンともいう．乳酸菌Leuconostoc mesenteroidesやL. dextranicumなどによって，スクロースから生成する(α1→6)結合を主体とする粘質性のグルカン．分子構造は生産菌株によって異なり不均性が高いが，65％ 以上の(α1→6)結合をもつものをいう．平均分子量は少なくとも4×106．[α]D＋180～＋210°(水)．α-D-1,4-，α-D-1,3-，α-D-1,2-結合を分岐鎖にもつが，α-D-1,3-結合が多い．デキストランを希酸で部分分解し，平均分子量7.5万～10万としたものは代用血漿として輸血に用いられるほか，ビールの醸造の際に，麦芽に添加して泡持ちをよくしたり，アイスクリーム，そのほかの食品の粘性保持のために用いられる．また，分子量2000～4000のデキストランを部分的に硫酸エステル化して分子量6500程度にしたものは，デキストラン硫酸(dextran sulfate)とよばれ，血液凝固阻止作用，抗食餌性脂血症の清澄作用を示し，経口的動脈硬化治療剤として使われている．そのほか，種々の分子量のものをエピクロロヒドリンで架橋して不溶化したものが，セファデックスの名称で生化学的ゲル濾過剤(アフィニティークロマトグラフィーの担体)として用いられる．LD50 10700 mg/kg(ラット，皮下)． | | 化粧品の成分用途 | キレート剤、保湿.湿潤剤、結合剤、吸着剤、増量剤 | | 効能 | 血流改善, 血漿増量剤 | | 説明 | Dextrans are glucose polymers produced by bacteria linked in
an α-1,6 chain and having an α-1,3 or α-1,4 branch about every fifth residue. The specific
positioning of the branching varies by the bacterium producing it. The molecular weights of these
chains generally are 40 or 70 kDa (dextran-40 and dextran-70, respectively), and the compounds
work via an osmotic gradient similar to the colloids and hypertonic crystalloid solutions.
Dextrans have a longer intravascular
residence time
than albumin, which limits interstitial edema. As with the crystalloids and other colloids, the dextrans
have no oxygen-carrying capacity. Furthermore, because they are bacterial products, the dextrans
have the potential to be potent antigens and induce anaphylaxis. | | 化学的特性 | white crystals or powder | | Originator | LMD 10%,Abbott,US,1967 | | 使用 | Dextran is a polysaccharide composed of glucose molecules used as an antithrombotic to reduce blood viscosity and as a volume expander in anemia. Studies show that it inhibits the mannose receptor-med
iated clearance of tissue-type plasminogen activator (t-PA). | | 使用 | antiinflammatory veterinary drug | | 使用 | dextran is a polysaccharide with water-binding properties. It is also used to control product viscosity. Some studies indicate a capacity to enhance the anti-aging activity of formulations containing weak acids, as well as to reduce possible skin irritation arising from such acids. | | 使用 | also available in pharma grade | | 使用 | exhibit borad spectrum of biological activities, with very low anticoagulant capacity: they activate lipoprotein elimination by lipase stimulation, inhibit cell proliferation in vascular wall, regulate transport of plasmatic proteins and inhibit depositi | | 定義 | dextran: A glutinous glucose polymerproduced by certain bacteria. Itcan be made by fermenting sucrose(cane sugar) and is used as a thickeningagent, as a stabilizer in ice cream,and as a substitute for plasma inblood transfusions. Esters with sulphuricacid yield sodium salts thatare employed as anticoagulant drugs. | | Manufacturing Process | Sucrose is subjected to the action of the bacterium Leuconosfoc
mesenteroides B 512 and the crude, high-molecular weight dextran thus
formed is hydrolyzed and fractionated to an average molecular weight of
about 40,000 as measured by light-scattering techniques. | | brand name | Gentran 40
(Baxter Healthcare). | | Therapeutic Function | Plasma extender | | 一般的な説明 | Dextrans are polysaccharides with molecular weights ≥1,000 Dalton, with a linear backbone of α-linked D-glucopyranosyl repeating units. Dextrans are found as bacterial extracellular polysaccharides. They are synthesized from sucrose by Leuconostoc mesenteroides and Lactobacillus brevis. Bacteria employ dextran in biofilm formation or as a protective coating to evade host phagocytes in the case of pathogenic bacteria.
Dextran from Leuconostoc mesenteroides (Mw: 12,000) may be used as an analytical standard to calibrate the column for gel permeation chromatography (GPC). | | Biochem/physiol Actions | Dextran is a branched glucan composed of linear a(1→6) linked glucose units and a (1→3) link initiated branches. Dextran ranges in size from 10,000 to 150,000 Kd. Dextrans are used in many applications as volume extenders, stabilizers, matrix components, binding platforms, lubricants and physical structure components. | | 作用機序 | | | 安全性プロファイル | Suspected carcinogen
with experimental carcinogenic data. When
heated to decomposition it emits acrid
smoke and fumes. See also other
DEXTRANS. | | Veterinary Drugs and Treatments | Dextran 70 is a relatively low cost colloid for the adjunctive treatment
of hypovolemic
shock. Hetastarch is the more commonly employed
synthetic colloid used today. | | 純化方法 | Solutions of dextran keep indefinitely at room temperature if 0.2mL of Roccal (10% alkyldimethylbenzylammonium chloride) or 2mg phenyl mercuric acetate are added per 100mL solution. This inhibits mould growth. [Scott & Melvin Anal Biochem 25 1656 1953.] |
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