Maturation and survival of Cronobacter biofilms on silicone, polycarbonate, and stainless steel after UV light and ethanol immersion treatments.
Cronobacter sakazakii cells in biofilms formed on silicone, polycarbonate, and stainless steel coupons immersed in reconstituted powdered infant milk formula were treated with ethanol (10 to 70%) and UV light (12 to 2,160 mW.s/cm(2)) as antibacterial treatments. Biofilm maturation curves were determined after immersion at 25 degrees C for up to 144 h. Populations increased after subsequent immersion at 25 degrees C for 24 h in reconstituted powdered infant milk formula to the respective maximum levels of 7.96, 7.91, and 6.99 log CFU per coupon. Populations attached to silicone and polycarbonate surfaces to a greater extent than to stainless steel (P < 0.05). Treatment with 10% ethanol did not cause a significant decrease in the level of C. sakazakii, but treatment with 30, 40, and 50% ethanol reduced the levels to approximately 1.73, 3.02, and 4.17 log CFU per coupon, respectively. C. sakazakii was not detected on any coupon after treatment with 70% ethanol or 2,160 mW.s/cm(2) UV light. A synergistic effect of sequential ethanol and UV treatments was not observed.
Jo
Seo-Hee
SH
Department of Food Science and Technology, Chung-Ang University, 72-1 Naeri, Ansung, Gyunggi-do 456-756, South Korea.
Baek
Seung-Bum
SB
Ha
Ji-Hyoung
JH
Ha
Sang-Do
SD
D001422:Bacterial Adhesion / Q000502:physiology; D018441:Biofilms / Q000254:growth & development*; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D044083:Cronobacter sakazakii / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D000431:Ethanol / Q000494:pharmacology*; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D006801:Humans; D007223:Infant; D007225:Infant Food / Q000382:microbiology*; D041943:Infant Formula; D007231:Infant, Newborn; D011076:Polycarboxylate Cement; D012828:Silicones; D013193:Stainless Steel; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014466:Ultraviolet Rays
D011076:Polycarboxylate Cement; D012828:Silicones; D013193:Stainless Steel; C005506:polycarbonate; D000431:Ethanol