The symbiotic effect of temperature and sugars on the planktonic growth and biofilm formation of Klebsiella spp. isolated from traditionally made cheese

In this paper, we have investigated the influence of temperatures (4 degrees C, 37 degrees C, 44 degrees C) and different concentrations of glucose and lactose (0.5%, 1.5%, 2.5%, 3.5%) on the planktonic growth, biofilm formation and formed biofilm s of Klebsiella oxytoca, Klebsiella ornithinolytica and Klebsiella pneumoniae in two different broths (TSB and MH). The bacteria were isolated from the cheese produced in Southeastern region of Serbia. Klebsiella pneumoniae ATCC 70063 was used as a positive control. The planktonic growth and biofilm formation were measured using spectrophotometric method. A different planktonic growth and biofilm formation was observed in the two liquid media. At 4 degrees C, the planktonic growth was not observed, neither was the formation of biofilm. The temperatures of 37 degrees C and 44 degrees C, as well as various concentrations of glucose and lactose, stimulated the planktonic growth of bacteria. The biofilm formation was less affected by glucose, but lactose stimulated the biofilm formation. These results were in accordance with the origin of bacteria, since the isolates were obtained from cheese. The intensity of the effect of sugars on the planktonic growth and biofilm formation depended on the bacterial species.