Solar inactivation of mesophilic Aeromonas by exogenous photooxidation in high-rate algal pond treating waste water.
OBJECTIVE
Investigations were carried out to observe the effect of sunlight on the survival of mesophilic Aeromonas (A. caviae, A. hydrophila and A. sobria) in high-rate algal pond.


RESULTS
Light damage was estimated by loss of bacterial culturability, using simple beaker experiments. Survival of the strains studied under illuminated conditions was highly affected by the physico-chemical conditions within the microcosms. The inactivation of Aeromonas increased strongly as dissolved oxygen was increased, and was dependent on exogenous sensitizers. This process was enhanced by the high pH of water. Die-off of bacteria was prevented by adding catalase and pyruvate (H2O2 scavengers) into the microcosms.


CONCLUSIONS
The damage of Aeromonas was mainly due to exogenous photooxidation. Hydrogen peroxide at least was involved in light-induced damage of bacteria. Aeromonas sobria appeared to be slightly less sensitive to photooxidation than A. hydrophila and A. caviae.


CONCLUSIONS
The present study could explain the relative resistance of A. sobria to treatment in wastewater stabilization ponds.
Benchokroun
S
S
Université Cadi Ayyad, Faculté des Sciences Semlalia, Département de Biologie, Laboratoire de Microbiologie, Marrakesh, Morocco.
Imziln
B
B
Hassani
L
L
D000333:Aeromonas / Q000254:growth & development / Q000528:radiation effects*; D000693:Anaerobiosis / Q000502:physiology; D015169:Colony Count, Microbial; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D013242:Sterilization; D013472:Sunlight; D014865:Waste Disposal, Fluid / Q000379:methods*; D014871:Water Microbiology
D006861:Hydrogen Peroxide