The effect of volatile fatty acids in acidified fermented piggery effluent on shiga-toxigenic and non-toxic resident strains of Escherichia coli.
OBJECTIVE
To examine the effects of acidified acidogenically fermented piggery effluent containing Volatile Fatty Acids (VFA) on shiga-toxigenic and resident strains of Escherichia coli (E. coli) as part of the development of a waste treatment process.


RESULTS
Four shiga-toxigenic E. coli strains (O157:H7, 091.H-, 0111.H-, and 0123.H-) and four non-toxic resident enzootic strains were all killed by 3 h treatment with fermented piggery effluent liquor (153 mmol l(-1) total VFA) at pH 4.3. The shiga-toxigenic strains showed greater sensitivity after 1 h of treatment. The fermented liquor at pH 6.8 was not inhibitory.


CONCLUSIONS
The shiga-toxigenic strains were no more resistant to the toxic effects of VFA than the non-toxic strains tested.


CONCLUSIONS
Shiga-toxigenic strains and resident enzootic non-toxigenic strains are equally susceptible to inactivation by this waste treatment process and by acidified VFA in general.
Harris
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Fungi-Gulp Research Group, School of Veterinary Science, Faculty of Natural Resources, Agriculture and Veterinary Science, University of Queensland, Brisbane, Queensland 4072, Australia. ivorharris@hotmail.com
Henry
D P
DP
Frost
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A
D000818:Animals; D004926:Escherichia coli / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity; D005232:Fatty Acids, Volatile / Q000494:pharmacology*; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D008372:Manure / Q000382:microbiology*; D017744:Medical Waste Disposal / Q000379:methods*; D022603:Shiga Toxins / Q000096:biosynthesis; D013552:Swine; D013997:Time Factors
D005232:Fatty Acids, Volatile; D008372:Manure; D017744:Medical Waste Disposal; D022603:Shiga Toxins