Effectiveness of pulsed ultraviolet-light treatment for bacterial inactivation on agar surface and liquid medium.
In the present study, the efficiency of a broad-spectrum pulsed ultraviolet (UV)-light for the inactivation of Listeria monocytogenes Scott A, L. monocytogenes CNL 895807, and Pseudomonas fluorescens MF37 populations as agar seeded or suspended cells was investigated. The bacterial populations were treated by pulsed UV-light at different number of pulses (1 to 3), dose of energy (162, 243, or 324 J), and distance from the strobe (4, 9, or 12 cm). After pulsed UV-light treatment, the bacterial reduction was determined by standard plate count. The results showed that there was a significant reduction of population along with an increase of light energy and number of pulses. Decreasing the distance between the Petri dishes and the xenon lamp demonstrated an increase in bacterial reduction. Decontamination efficacy decreased significantly with the increase in level of contamination. This study demonstrates that pulsed UV-light can be used as an effective sterilizing method for the bacteria.
Ben Saïd
Noura Elmnasser
NE
UMR-INRA 1014 SECALIM ENVN/ENITIAA, Ecole Nationale Vétérinaire de Nantes, Nantes, France. mnassernoura@yahoo.fr
Federighi
Michel
M
Bakhrouf
Amina
A
Orange
Nicole
N
D000362:Agar; D058491:Bacterial Load / Q000528:radiation effects; D003470:Culture Media; D004307:Dose-Response Relationship, Radiation; D005514:Food Irradiation; D008089:Listeria monocytogenes / Q000528:radiation effects*; D011551:Pseudomonas fluorescens / Q000528:radiation effects*; D013242:Sterilization / Q000379:methods; D014466:Ultraviolet Rays
D003470:Culture Media; D000362:Agar