グラミシジン D 化学特性,用途語,生産方法
外観
本品は白色~淡黄白色の結晶性の粉末である.
本品はメタノールに溶けやすく,エタノール(99.5)にやや
溶けやすく,水にほとんど溶けない.
確認試験
(1) 本品10mgに6mol/L塩酸試液2mLを加え,時々振り混
ぜながら水浴中で30分間加熱する.冷後,6mol/L水酸化ナ
トリウム試液で中和した後,ニンヒドリン試液1mL及びピ
リジン0.5mLを加えて2分間加熱するとき,液は青紫色~赤
紫色を呈する.
(2) 本品のエタノール(95)溶液(1→20000)につき,紫外可
視吸光度測定法により吸収スペクトルを測定し,本
品のスペクトルと本品の参照スペクトル又はグラミシジン標
準品について同様に操作して得られたスペクトルを比較する
とき,両者のスペクトルは同一波長のところに同様の強度の
吸収を認める.
定量法
次の条件に従い,抗生物質の微生物学的力価試験法〈4.02〉の比濁法により試験を行う.
(ⅰ) 試験菌 Enterococcus hirae ATCC 10541を用いる.
(ⅱ) 試験菌移植用カンテン培地 ブドウ糖10.0g,カゼイ
ン製ペプトン5.0g,醗母エキス20.0g,リン酸二水素カリウ
ム2.0g,ポリソルベート80 0.1g及び,カンテン15.0gをとり,
水1000mLを加え,滅菌後のpHが6.7~6.8となるように調整
した後,滅菌する.
(ⅲ) 試験菌懸濁用液状培地 培地(2)を用いる.
(ⅳ) 試験菌液の調製 試験菌を試験菌移植用カンテン培地
約10mLを内径約16mmの試験管に分注した高層培地に穿刺
し,36.5~37.5℃で20~24時間,少なくとも3回継代培養し
た後,1~5℃に保存する.この継代培養した菌を試験菌懸
濁用液状培地10mLに移植し,36.5~37.5℃で20~24時間培
養し,試験菌原液とする.用時,この試験菌原液を試験菌懸
濁用液状培地に加え,波長580nmにおける透過率が50~
60%になるように調整し,この液1容に試験菌懸濁用液状培
地200容を加え,試験菌液とする.
(ⅴ) 標準溶液 グラミシジン標準品適量を60℃で3時間減
圧(0.67kPa以下)乾燥し,その約10mg(力価)に対応する量を
精密に量り,エタノール(99.5)に溶かして正確に100mLとし,
標準原液とする.標準原液は5℃以下に保存し,7日以内に
使用する.用時,標準原液適量を正確に量り,プロピレング
リコール390mLにエタノール(99.5)/アセトン混液(9:1)
210mL及び滅菌精製水適量を加えて1000mLとした液を加
えて1mL中に0.02μg(力価)を含む液を調製し,標準溶液とす
る.
(ⅵ) 試料溶液 本品約10mg(力価)に対応する量を精密に量
り,エタノール(99.5)に溶かし,正確に100mLとする.この
液適量を正確に量り,プロピレングリコール390mLにエタ
ノール(99.5)/アセトン混液(9:1)210mL及び滅菌精製水適
量を加えて1000mLとした液を加えて1mL中に0.02μg(力価)
を含む液を調製し,試料溶液とする.
(ⅶ) 操作法 標準溶液0.155mL,0.125mL,0.100mL,
0.080mL及び0.065mL,試料溶液0.100mL,及びプロピレ
ングリコール390mLにエタノール(99.5)/アセトン混液
(9:1)210mL及び滅菌精製水適量を加えて1000mLとした液
0.100mLずつをとり,それぞれ内径約14mm,長さ約15cm
の試験管3本ずつに入れる.各試験管に試験菌液10mLを加
え,ふたをし,36.5~37.5℃の水浴中で180~270分間培養
する.培養後,ホルムアルデヒド液溶液(1→3)0.5mLを各試
験管に加え,波長580nmにおける透過率を測定する.
貯法
容器 気密容器.
乾燥減量
3.0%以下(0.1g,減圧,60℃,3時間).
強熱残分
1.0%以下(1g).
説明
Gramicidin is a polypeptide antibiotic mixture of gramicidin A , gramicidin B, and gramicidin C originally isolated from
B. brevis. It is also a component of the antibiotic tyrothricin . Gramicidin is active against the Gram-positive bacterium
S. aureus but not Gram-negative
E. coli. It also protects mice from
Pneumococcus infection
in vivo when administered at a dose of 0.002 mg/animal. Gramicidin inhibits growth of bacteria by forming pores and channels in the cell wall, which increases its permeability to monovalent cations. Formulations containing gramicidin have been used as topical agents in the treatment of bacterial skin infections.
化学的特性
White, crystalline platelets. Soluble in lower alcohols, acetic acid, and
pyridine; moderately soluble in dry acetone and
dioxane; almost insoluble in water, ether, and
hydrocarbons. Depresses surface tension, forms a
fairly stable colloidal emulsion in distilled water.
使用
Gramicidins are a family of linear pentadecapeptides isolated from Bacillus brevis by Dubos at the Rockefeller Institute in 1939. Gramicidin is a complex of six closely related analogues A1, A2, B1, B2, C1 and C2 where A1 and A2 are the dominant components. Gramidicins act by forming channels in cell membranes causing ion leakage, and is an essential bioprobe for understanding the nature of the cell membranes.
定義
An antibiotic produced by the metabolic processes of the bacteria Bacillus brevis. It is a polypeptide that is active against most Gram-positive pathogenic bacteria. It is one of the two antibiotic components of tyrothricin but has been isolated and used
一般的な説明
Gramicidin is obtained from tyrothricin, a mixture ofpolypeptides usually obtained by extraction of cultures of B.brevis. Tyrothricin was isolated in 1939 by Dubos in aplanned search to find an organism growing in soil that wouldhave antibiotic activity against human pathogens. With onlylimited use in therapy now, it is of historical interest as thefirst in the series of modern antibiotics. Tyrothricin is a whiteto slightly gray or brown-white powder, with little or no odoror taste. It is practically insoluble in water and is soluble in alcoholand dilute acids. Suspensions for clinical use can beprepared by adding an alcoholic solution to calculatedamounts of distilled water or isotonic saline solutions.
Gramicidin acts as an ionophore in bacterial cell membranesto cause the loss of potassium ion from the cell. Itis bactericidal.Tyrothricin and gramicidin are effective primarilyagainst Gram-positive organisms. Their use is restricted tolocal applications. Tyrothricin can cause lysis of erythrocytes,which makes it unsuitable for the treatment of systemicinfections. Its applications should avoid direct contactwith the bloodstream through open wounds or abrasions. Itis ordinarily safe to use tyrothricin in troches for throat infections,as it is not absorbed from the GI tract. Gramicidinis available in various topical preparations containing otherantibiotics, such as bacitracin and neomycin.
応用例(製薬)
Gramicidin as used in topical formulations is a mixture of
several closely related compounds, of which about 80% is in
the form of gramicidin A. It is part of the tyrothricin complex
originally isolated from B. brevis.
It is active against most species of Gram-positive bacteria,
including mycobacteria. Gram-negative bacilli are completely
insensitive.
It is highly toxic to erythrocytes, liver and kidney, and is
used only in topical formulations, usually as one of several
components.
グラミシジン D 上流と下流の製品情報
原材料
準備製品