Abstract
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 µg/ml endotoxin solution at 121°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.
- Received March 27, 1995.
- Accepted August 23, 1995.
- Copyright © Parenteral Drug Association. All rights reserved.
PDA members receive access to all articles published in the current year and previous volume year. Institutional subscribers received access to all content. Log in below to receive access to this article if you are either of these.
If you are neither or you are a PDA member trying to access an article outside of your membership license, then you must purchase access to this article (below). If you do not have a username or password for JPST, you will be required to create an account prior to purchasing.
Full issue PDFs are for PDA members only.
Note to pda.org users
The PDA and PDA bookstore websites (www.pda.org and www.pda.org/bookstore) are separate websites from the PDA JPST website. When you first join PDA, your initial UserID and Password are sent to HighWirePress to create your PDA JPST account. Subsequent UserrID and Password changes required at the PDA websites will not pass on to PDA JPST and vice versa. If you forget your PDA JPST UserID and/or Password, you can request help to retrieve UserID and reset Password below.