ISSN:
1432-072X
Keywords:
Organic hydroperoxides
;
Bacterial spores
;
Oxidative killing
;
Antioxidants
;
Minerals
;
Bacillus megaterium
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Tertiary butyl hydroperoxide (t-BOOH) was found to be sporicidal for Bacillus megaterium ATCC19213. Sporicidal action was very temperature dependent, and the potency of t-BOOH increased about tenfold for each increase in temperature of 15 °C over the range from 30° to 70 °C. At still higher temperatures, heat and μmolar levels of t-BOOH were mutually potentiating for killing. Vegetative cells and germinated spores were some thousand times less resistant to t-BOOH than dormant spores. The order of resistance for spores was: Bacillus stearothermophilus ATCC7953 〉 Bacillus subtilis var. niger = Bacillus megaterium ATCC33729 〉 Bacillus megaterium ATCC19213. Killing was not enhanced by decoating and occurred without germination or loss of refractility of the spores. Spore resistance to t-BOOH was lower at more acid pH values and was decreased also by demineralization. Spores could be protected by the chelator o-phenanthroline, especially in association with Fe2+. Overall, it seemed that killing was associated with nonmetabolic formation of alkyl peroxyl radicals, which are thought to be responsible for killing of vegetative cells by organic hydroperoxides.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00276481
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