EFFECT OF GROWTH TEMPERATURE AND BIOFILM AGE ON THE RESISTANCE OF SALMONELLA TYPHIMURIUM BIOFILMS TO BACTERIOPHAGE

Salmonella Typhimurium is among the most important food-borne disease. This study was conducted to investigate the anti-biofilm effect of the S. Typhimurium phage against Salmonella formed in chicken meat model.
The effects of different phage concentrations (104, 106 and 108 PFU/mL) with two contact times (10 and 20 min) on one and 7 days old biofilm adhered to stainless steel coupon in chicken broth at 15, 8 and 4 °C were evaluated.
The results showed that the bacteria had an ability to adhere to the coupons and form biofilm in chicken broth, the biofilm levels were significantly (0.05 ≥ P) higher at 15 °C for 7 days. Increasing the phage concentrations, resulted in no significant biofilm removal properties and the activity was not influenced by the phage contact times. The anti-biofilm activity was influenced by the age of biofilm, in this case, one day-old biofilm was more sensitive than 7 days old.
From the study it can be concluded, that in chicken model, the phage exhibited biofilm removal activity on Salmonella only at high concentrations, then the use of a combination of methods to control biofilm is recommended.