An effective iodide formulation for killing Bacillus and Geobacillus spores over a wide temperature range.
OBJECTIVE
To develop a sporicidal reagent which shows potent activity against bacterial spores not only at ambient temperatures but also at low temperatures.


RESULTS
Suspension tests on spores of Bacillus and Geobacillus were conducted with the reagent based on a previously reported agent (N. Kida, Y. Mochizuki and F. Taguchi, Microbiology and Immunology 2003; 47: 279-283). The modified reagent (tentatively designated as the KMT reagent) was composed of 50 mmol l(-1) EDTA-2Na, 50 mmol l(-1) ferric chloride hexahydrate (FeCl(3).6H(2)O), 50 mmol l(-1) potassium iodide (KI) and 50% ethanol in 0.85% NaCl solution at pH 0.3. The KMT reagent showed significant sporicidal activity against three species of Bacillus and Geobacillus spores over a wide range of temperature. The KMT reagent had many practical advantages, i.e. activity was much less affected by organic substances than was sodium hypochlorite, it did not generate any harmful gas and it was stable for a long period at ambient temperatures. The mechanism(s) of sporicidal activity of the KMT reagent was considered to be based on active iodine species penetrating the spores with enhanced permeability of the spore cortex by a synergistic effect of acid, ethanol and generated active oxygen.


CONCLUSIONS
The data suggest that the KMT reagent shows potent sporicidal activity over a wide range temperatures and possesses many advantages for practical applications.


CONCLUSIONS
The results indicate development of a highly applicable sporicidal reagent against Bacillus and Geobacillus spores.
Kida
N
N
Niigata Quarantine Station, Ministry of Health, Labour and Welfare, Ryugashima, Niigata, Niigata, Japan. n-kida@forth.go.jp
Mochizuki
Y
Y
Taguchi
F
F
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001407:Bacillus / Q000187:drug effects*; D001409:Bacillus cereus / Q000187:drug effects; D001412:Bacillus subtilis / Q000187:drug effects; D002712:Chlorides; D003116:Color; D003343:Corrosion; D003470:Culture Media; D004492:Edetic Acid / Q000494:pharmacology; D000431:Ethanol / Q000494:pharmacology; D005290:Ferric Compounds / Q000494:pharmacology; D001411:Geobacillus stearothermophilus / Q000187:drug effects; D008670:Metals; D011193:Potassium Iodide / Q000494:pharmacology*; D013171:Spores, Bacterial / Q000187:drug effects; D013696:Temperature
D000900:Anti-Bacterial Agents; D002712:Chlorides; D003470:Culture Media; D005290:Ferric Compounds; D008670:Metals; D011193:Potassium Iodide; D000431:Ethanol; D004492:Edetic Acid; C024555:ferric chloride