The Petri dish was located at a distance
of 5 cm from two 32W UV-C lamps (VL-208G, Vilber, Germany)
with a fluence of 8.0 ± 0.2 mW/cm2 measured with a UVX radiometer
(UVP, LLC, Upland, CA). The contaminated treatment media was agitatedwith
amagnetic stirrer at 250 rpm, and 250 μL sampleswere taken at
preset treatment times. The entire system was placed inside an incubator
with an air temperature of 24 °C. The same methodology and
equipment were also used to treat and measure the McIlvaine solutions
of aw of 0.66 and 0.40 respectively, since they could not be
pumped through the UV-1 system due to their viscosity. A reference
solution of aw N 0.99 was also treated in the UV-2-systemfor comparison
purposes.