Feeding grain to animals not adapted to grain resulted in a marked increase in the ./. concentration of free endotoxln m the rumen. Endotoxin concentration increased 15 to 18 times within 12 hr after lactic acidosis was induced through grain engorgement. The increase was accompanied by a shift from predominantly gram-negative to gram-positive bacteria. Data from in vitro fermentations showed that the increase in free endotoxin concentration was not accompanied by a decrease in the number of gram-negative bacteria. The absorption of endotoxin from the rumen was not apparent by the actinomycin D assay procedure because no difference was observed in mice lethality of plasma from control and post-engorgement samples. However, the significant granulocytosis that accompanied acidosis was suggestive of systemic action of rumen bacterial endotoxin.
Combinations of the broad spectrum, demand-type quaternary ammonium resin-polyiodide bactericide and virucide were prepared in the triiodide, pentaiodide, and heptaiodide forms by fluidized bed method in a closed aqueous system at elevated temperatures. The resin-triiodide combination is now in use as a disinfectant for water. The triiodide disinfectant prepared by this method is equal to the product obtained by a room temperature batch contact process and can be prepared in a considerably shorter time. Analyses of the supernatant solutions revealed increasingly higher iodine concentrations with higher polyiodide species in the resin combination. A long run elution study of one resin-pentaiodide combination is reported. All combinations, from triiodide to heptaiodide, were in the form of black, shiny beads, with increasing contraction of the beads observed with increasing iodine content. A significant fraction of the resin-heptaiodide beads were fractured due to internal stresses which caused the contraction.
Quaternary ammonium strong base anion-exchange resins in the triiodide form are extremely effective demand-type bactericides and virucides in water. The rapid release of iodine upon demand indicates a very efficient iodine transport system within the resin bead. Anion exchange of triiodide ion on these resins for common anions such as chloride, nitrate, and sulfate in solution is inhibited. A benzyl group in the quaternary ammonium exchange site appears necessary to effect the low solubility and inhibited anion exchange of triiodide. Completely aliphatic quaternary ammonium anion exchangers and anion-exchange resins lacking a benzyl group in the quaternary ammonium exchange site exhibit nearly normal exchange of triiodide ion. At pH values greater than 9.5, extensive hydrolysis of triiodide to hypoiodite occurs but at pH values less than 8.5, release of oxidizing species is below 0.2 ppm.Treatment with an alkylating agent to ensure complete quaternization of the exchange sites on an anion-exchange resin is marginally effective if a significant percentage of the sites are tertiary amine groups.
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