Bamba T, Matsui R, Watabe K
Pharmaceutical Research Center, Shiseido Company, Limited, Yokohama, Japan.
PDA J Pharm Sci Technol. 1996 Mar-Apr;50(2):129-35.
The inactivation of endotoxin from six species of smooth gram-negative bacteria (S-form) by steam-heat treatment was investigated using the Limulus amebocyte lysate (LAL) assay. Biphasic decreases of endotoxins from four species of bacteria were observed upon steam-heat treatment of 1 microgram/ml endotoxin solution at 121 degrees C in a steam sterilizer. A lag time, however, was observed in the inactivation profiles of V. cholerae and P. aeruginosa. Distinct differences in heat resistance were observed among the bacterial species. The decrease rate was found to be concentration-dependent, and endotoxins at low concentrations (less than 10 ng/ml) were inactivated by the treatment to below the detection limit of the LAL assay. The time-course of the decrease of endotoxin from rough strains (R-form) resembled that of the respective S-form. The inactivation of R-form, especially Rc mutant, endotoxin was markedly affected by divalent cations such as Mg2+ and Ca2+, which appear to promote reaggregation of the endotoxin.
使用鲎试剂检测法研究了蒸汽热处理对六种光滑型革兰氏阴性菌（S型）内毒素的灭活作用。在蒸汽灭菌器中于121℃对1微克/毫升内毒素溶液进行蒸汽热处理时，观察到四种细菌的内毒素呈现双相减少。然而，霍乱弧菌和铜绿假单胞菌的灭活曲线中观察到有一个延迟期。不同细菌种类之间观察到耐热性存在明显差异。发现减少速率与浓度有关，低浓度（小于10纳克/毫升）的内毒素经处理后被灭活至低于鲎试剂检测法的检测限。粗糙型菌株（R型）内毒素减少的时间进程与相应的S型相似。R型内毒素，尤其是Rc突变体内毒素的灭活受到Mg2+和Ca2+等二价阳离子的显著影响，这些阳离子似乎促进了内毒素的重新聚集。
