Selective medium for isolation of Clostridium botulinum from human feces

Abstract

A selective medium, Clostridium botulinum isolation (CBI) agar, was developed for the isolation of C. botulinum from human feces. This medium contains cycloserine (250 ,ug/ml), sulfamethoxazole (76 ytg/ml), and trimethoprim (4 gg/ ml) as selective inhibitory agents. Qualitative tests indicated complete recovery of C. botulinum types A, B, F, and G on CBI medium. It was more difficult to recognize type G colonies on the medium because of their lack of lipase activity. Except for a few species of Clostridium, the growth of other obligate anaerobes and of the facultative anaerobes tested on CBI medium was suppressed. Quantitative studies of C. botulinum on the selective medium yielded counts comparable to those obtained on egg yolk agar control plates. Isolation of C. botulinum types A, B, and F from seeded fecal specimens was easily achieved with CBI medium. The use of CBI agar should aid the rapid isolation of C. botulinum from fecal specimens associated with foodborne and infant botulism.

Transposon Tn916 mutagenesis in Clostridium botulinum

“…Escherichia coli strains were maintained and grown in Luria-Bertani broth (17). C. botulinum isolation agar, which contains 5% egg yolk and three antibiotics (cycloserine, trimethoprim, and sulfamethaxazole), was used as a selective medium for C. botulinum (8). A defined synthetic medium, MI medium (23), was used for detecting auxotrophs of C. botulinum.…”

Optimization of Polymerase Chain Reaction for Detection of Clostridium botulinum Type C and D in Bovine Samples

“…An alternative method to 'purify' samples has yet to be discovered. In this light, miscellaneous methods can be proposed: antibiotic treatment to eliminate contaminant bacteria (a mixture of cycloserine 1%, sulfomethoxazole 1.9% and trimethoprim 0.1% is already used in some cases; Dezfulian et al, 1981); development of a matrix capable of eliminating the Taq polymerase inhibitors directly from the samples or refining methods permitting the recovery of merely C. botulinum DNA after extraction.…”

Botulinum neurotoxins: mode of action and detection

“…The quest for novel food types and the need to reduce heat processing to improve quality, whilst still maintaining food safety, has increased the need for rapid, sensitive and specific tests for the detection of Clostridium botulinum and its toxins in food samples. Though enrichment broths for clostridial species have been developed selective growth of the species is time-consuming (Dezfulian et al 1981). A number of highly sensitive assays for the detection of Cl.…”