Effect of water activity and pH on growth and toxin production by Clostridium botulinum type G
| Autor: | E A de Lagarde, Jorge Briozzo, Jorge Chirife, J. L. Parada |
|---|---|
| Rok vydání: | 1986 |
| Předmět: |
Sucrose
Botulinum Toxins Hot Temperature Water activity ph Sodium water chemistry.chemical_element bacterial growth medicine.disease_cause Applied Microbiology and Biotechnology Microbiology chemistry.chemical_compound medicine Clostridium botulinum Trypsin Food science botulinum toxin Support Non-U.S. Gov't Incubation clostridium botulinum type g nonhuman Ecology Toxin activity Water Hydrogen-Ion Concentration Heat Spore Culture Media chemistry priority journal Food Science Biotechnology medicine.drug Research Article |
| Zdroj: | APPL. ENVIRON. MICROBIOL. 1986;51(4):844-848 Biblioteca Digital (UBA-FCEN) Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales instacron:UBA-FCEN |
| ISSN: | 0099-2240 |
| Popis: | The combined effect of water activity (a(w)) and pH on growth and toxin production by Clostridium botulinum type G strain 89 was investigated. The minimum a(w) at which growth and toxin formation occurred was 0.965, for media in which the pH was adjusted with either sodium chloride or sucrose. The minimum pH (at the optimum a(w)) for growth and toxin production of C. botulinum type G was found to be 5.6. Optimum conditions for toxin activation were a trypsin concentration of 0.1%, a pH of the medium of 6.5, and an incubation for 45 min at 37° C. These data did not show evidence of heat-labile spores, since a heat shock of 75°C for 10 min did not significantly decrease the spore count of strain 89G in media at pH 7.0 or 5.6. It was frequently observed that cells grown at reduced a(w) or pH experienced severe morphological changes. Fil:Briozzo, J. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. |
| Databáze: | OpenAIRE |
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