- Turkish Journal of Biology
- Vol: 38 Issue: 3
- Inhibitory effect of enterocin KP in combination with sublethal factors on Escherichia coli O157:H7 ...
Inhibitory effect of enterocin KP in combination with sublethal factors on Escherichia coli O157:H7 or Salmonella Typhimurium in BHI broth and UHT milk
Authors : Zeliha Yildirim, Yaselin Ilk, Metin Yildirim, Kader Tokatli, Nilgün Öncül
Pages : 412-419
Doi:10.3906/biy-1310-69
View : 10 | Download : 4
Publication Date : 9999-12-31
Article Type : Makaleler
Abstract :The effects of physical and chemical sublethal treatments on the antibacterial activity of enterocin KP produced by Enterococcus faecalis KP against Escherichia coli O157:H7 and Salmonella Typhimurium were investigated. Enterocin KP was not active against intact cells of E. coli O157:H7 or S. Typhimurium. However, the use of enterocin KP together with ethylenediaminetetraacetic acid (50 mM), sodium tripolyphosphate (50 mM), sublethal heating (60 °C for 10 min), cold shock (-20 °C for 2 h), or acid stress (mixture of 40% lactic acid, 16% propionic acid, 16% acetic acid) in BHI medium decreased the cell number of E. coli O157:H7 by 7.27, 6.28, 3.39, 3.06, 4.20 log and S. Typhimurium by 7.21, 6.20, 3.64, 3.38, 3.98 log cfu/mL, respectively. The combination of enterocin KP with ethylenediaminetetraacetic acid decreased the cell number of E. coli O157:H7 in UHT milk to undetectable level, enterocin KP plus sodium tripolyphosphate or enterocin KP plus sublethal heating caused a reduction by 6.07 and 5.68 log cycles. The results of this study showed that enterocin KP could be applied as a biopreservative to inhibit E. coli O157:H7 and S. Typhimurium in combination with physical and food grade chemical hurdles.Keywords : Key words: Bacteriocin, enterocin KP, sublethal injury, gram-negative bacteria, UHT milk