Nonspecific Toxicities in the Mouse Assay Test for Botulinum Toxin1

Abstract

In inoculated pack experiments on Clostridium botulinum type E, unirradiated and 0.1-Mrad irradiated haddock fillets often gave nonspecific toxicities by the mouse assay test for botulinum toxin. Samples given 0.2-Mrad radiation failed to produce nonspecific reactions. Nonspecific deaths sometimes occurred within 24 hr after injection, although deaths between 24 and 48 hr were more common. The symptoms and the pattern of these deaths suggested a septicemia. Heart-blood cultured from mice showing nonspecific symptoms indicated an infectious process. Among 23 isolates from the blood, eight were identified as Proteus vulgaris, two P. morganii, one P. rettgeri, one Providence subgroup B, two Aerobacter aerogenes, one Actinobacillus, three enterococci, one Alcaligenes marshalli, and four Erysipelothrix insidiosa. The E. insidiosa, Aerobacter, Providence group, and most of the Proteus isolates were infectious for mice when injected by the intraperitoneal route. But the enterococci, Alcaligenes, and Actinobacillus isolates were not infectious and probably represent secondary invaders. The cultural characteristics of the E. insidiosa isolates conform to those described in the literature, with the exception that the four strains grew in the temperature range 50 F (10 C) to 40 F (4.4 C). Nonspecific toxicities were avoided in assays for botulinum toxin by the protection of mice with chloramphenicol and oxytetracycline.

Behavior of Nonproteolytic Clostridium botulinum Type B and E Spores in Cooked Turkey and Modeling Lag Phase and Probability of Toxigenesis

“…Each sample was centrifuged at 27,000 x g for 20 min and the collected supernatant was adjusted to pH 6.2 using 1N HCL, then frozen until tested for toxicity. Freezing and recentrifuging samples helped eliminate nonspecific deaths (Segner and Schmidt, 1968). All samples were trvpsinized prior to intraparietal injection of mice.…”

Bovine serum eliminates rapid nonspecific toxic reactions during bioassay of stored fish for Clostridium botulinum toxin

“…The nonbotulinum-like deaths first occurred on the day of or immediately after the disappearance of oxygen in the packages. Death was rapid, usually within 1 to 2 h. Segner and Schmidt (9) reported nonspecific deaths during mouse botulinum assays of irradiated and nonirradiated haddock fillets inoculated with C. botulinum type E. Nonspecific deaths occurred between 24 and 48 h after injection. Bacteria isolated from marine environments are predominately gram-negative asporogenous rods (10).…”