Sporicidal kinetics of Bacillus subtilis spores by heated scallop shell powder
Jun Sawai1, Hiroyuki Miyoshi, Hiromitsu Kojima
1Department of Applied Chemistry, Kanagawa Institute of Technology, 1030 Shimo-Ogino, Atsugi, Kanagawa 243-0292, Japan. sawai@chem.kanagawa-it.ac.jp
Abstract:
Scallop shell powder heated at 1,000 degrees C for 1 h exhibited sporicidal action against Bacillus subtilis spores. The sporicidal kinetics of this action were analyzed with the use of a nonlogarithmic model. Apparent death rate constants (k) were obtained under various conditions. The value of k increased with powder concentration but became constant beyond the concentration representing the solubility of Ca(OH)2. A linear inverse relationship between k and temperature was found, and from this relationship the activation energy required for the death of B. subtilis spores in the heated shell powder slurry could be determined.
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