γ-シクロデキストリン 化学特性,用途語,生産方法
外観
白色～ほとんど白色, 結晶性粉末～粉末
定義
本品は、6~8のグルコピラノースからなる環状多糖類であり、次の化学式で表される。
環状構造：6~8
溶解性
水に溶けやすく、エタノールおよびアセトンにほとんど溶けない。
解説
シクロデキストリン，D-グルコピラノース単位がα-1,4-グルコシド結合で環状に結合した王冠状の化合物で，デンプンにBacillus maceransからとれたアミラーゼ(EC 2.4.1.19)を作用させると得られる．グルコース単位の数が6，7および8のものが知られており，γ-シクロデキストリンC48H80O40(1297.14)は[α]D＋177.4°(水)．内径0.9～1 nm．環のなかに種々のカチオンや有機化合物を取り込んで包接化合物を形成する．香料の揮発防止剤，脂肪酸やビタミンCの酸化防止剤，界面活性剤，そのほかに用いられる．
用途
酵素研究用、有機物物性改良研究用、有機合成用。
化粧品の成分用途
キレート剤、吸着剤
化学的特性
White powder or crystal
使用
A molecule used to solublize non-polar molecules such a cholesterol for use in cell culture.
調製方法
Cyclodextrins are manufactured by the enzymatic degradation of
starch using specialized bacteria. For example, β-cyclodextrin is
produced by the action of the enzyme cyclodextrin glucosyltransferase
upon starch or a starch hydrolysate. An organic solvent is
used to direct the reaction that produces β-cyclodextrin, and to
prevent the growth of microorganisms during the enzymatic
reaction. The insoluble complex of β-cyclodextrin and organic
solvent is separated from the noncyclic starch, and the organic
solvent is removed in vacuo so that less than 1 ppm of solvent
remains in the β-cyclodextrin. The β-cyclodextrin is then carbon
treated and crystallized from water, dried, and collected.
一般的な説明
Cyclodextrins belongs to the family of cyclic α-1,4-glucans and is made of glucose units. This molecule has a shape of a hollow cone. It possesses a hydrophilic external and hydrophobic internal surface, because of which cyclodextrins can form inclusion complexes. γ-Cyclodextrin is extensively used in food and pharmaceutical industries. Cyclodextrins are obtained by the enzymatic conversion of starch/starch derivatives by cyclodextrin glycosyltransferase.
応用例（製薬）
Cyclodextrins are ‘bucketlike’ or ‘conelike’ toroid molecules, with a rigid structure and a central cavity, the size of which varies according to the cyclodextrin type. The internal surface of the cavity is hydrophobic and the outside of the torus is hydrophilic; this is due to the arrangement of hydroxyl groups within the molecule. This arrangement permits the cyclodextrin to accommodate a guest molecule within the cavity, forming an inclusion complex.
Cyclodextrins may be used to form inclusion complexes with a variety of drug molecules, resulting primarily in improvements to dissolution and bioavailability owing to enhanced solubility and improved chemical and physical stability.
Cyclodextrin inclusion complexes have also been used to mask the unpleasant taste of active materials and to convert a liquid substance into a solid material. γ-cyclodextrin has the largest cavity and can be used to form inclusion complexes with large molecules;it has low toxicity and enhanced water solubility.
In parenteral formulations, cyclodextrins have been used to produce stable and soluble preparations of drugs that would otherwise have been formulated using a nonaqueous solvent.
In eye drop formulations, cyclodextrins form water-soluble complexes with lipophilic drugs such as corticosteroids. They have been shown to increase the water solubility of the drug; to enhance drug absorption into the eye; to improve aqueous stability; and to reduce local irritation.
Cyclodextrins have also been used in the formulation of solutions,suppositories, and cosmetics.
安全性
Cyclodextrins are starch derivatives and are mainly used in oral and
parenteral pharmaceutical formulations. They are also used in
topical and ophthalmic formulations.
Cyclodextrins are also used in cosmetics and food products, and
are generally regarded as essentially nontoxic and nonirritant
materials. However, when administered parenterally, β-cyclodextrin
is not metabolized but accumulates in the kidneys as insoluble
cholesterol complexes, resulting in severe nephrotoxicity.
Cyclodextrin administered orally is metabolized by microflora in
the colon, forming the metabolites maltodextrin, maltose, and
glucose; these are themselves further metabolized before being
finally excreted as carbon dioxide and water. Although a study
published in 1957 suggested that orally administered cyclodextrins
were highly toxic, more recent animal toxicity studies in rats and
dogs have shown this not to be the case, and cyclodextrins are now
approved for use in food products and orally administered
pharmaceuticals in a number of countries.
Cyclodextrins are not irritant to the skin and eyes, or upon
inhalation. There is also no evidence to suggest that cyclodextrins
are mutagenic or teratogenic.
γ-Cyclodextrin
LD50 (rat, IP): 4.6 g/kg
LD50 (rat ,IV): 4.0 g/kg
LD50 (rat, oral): 8.0 g/kg
貯蔵
Cyclodextrins should be stored in a tightly sealed container, in a
cool, dry place.Cyclodextrins are stable in the solid state if
protected from high humidity.
規制状況(Regulatory Status)
Included in the FDA Inactive Ingredients Database: α-cyclodextrin
(injection preparations); β-cyclodextrin (oral tablets, topical gels);
γ-cyclodextrin (IV injections).
Included in the Canadian List of Acceptable Non-medicinal
Ingredients (stabilizing agent; solubilizing agent ); and in oral and
rectal pharmaceutical formulations licensed in Europe, Japan, and
the USA.
γ-シクロデキストリン 上流と下流の製品情報
原材料
準備製品