Cooperstock M S
Antimicrob Agents Chemother. 1974 Oct;6(4):422-5. doi: 10.1128/AAC.6.4.422.
The limulus gelation assay was utilized to investigate endotoxin inactivation by a number of antibiotics in vitro. Endotoxin activity was sharply reduced by polymyxin B and sodium colistimethate. The effect of the polymyxin was not significantly inhibited by 0.001 M calcium or 90% serum. Crude endotoxins from a variety of aerobic gram-negative bacteria, including several not previously studied, could be inactivated 1 or more logs by as little as 1 mug of polymyxin B per ml, whereas Bacteroides fragilis endotoxin was poorly detoxified. A 10,000-fold range in the relative susceptibility of different endotoxins to inactivation by polymyxin B was found. The endotoxin most susceptible to polymyxin B was derived from an organism resistant to polymyxin B by disk sensitivity testing, suggesting that the bacteriocidal and endotoxin detoxifying properties of polymyxin need not be directly related.
利用鲎试剂凝胶化试验在体外研究多种抗生素对内毒素的灭活作用。多黏菌素B和黏菌素甲磺酸钠可使内毒素活性急剧降低。0.001 M钙或90%血清对多黏菌素的作用无明显抑制。来自多种需氧革兰氏阴性菌（包括几种此前未研究过的细菌）的粗制内毒素，每毫升只需1微克多黏菌素B就能使其失活1个或更多对数，而脆弱拟杆菌内毒素的解毒效果较差。发现不同内毒素对多黏菌素B灭活作用的相对敏感性范围达10000倍。对多黏菌素B最敏感的内毒素源自一株通过纸片药敏试验对多黏菌素B耐药的菌株，这表明多黏菌素的杀菌和内毒素解毒特性不一定直接相关。
