SURVIVAL OF Bacillus cereus LSPQ 2872 AND Escherichia coli O157:H7 UNDER GAMMA RADIATION MODELED WITH TSALLIS ENTROPY

The objective was to model the survival of Bacillus cereus LSPQ 2872 and Escherichia coli O157:H7 exposed to gamma radiation, using Tsallis entropy and the Monte Carlo simulation method. Monte Carlo simulations were performed with a noise level of 0.05 to assess the sensitivity of the Tsallis entropy-based models (dose-proportional effect, linear-quadratic dose-effect relationship, and Sotolongo et al.). Random values were generated for the parameters (α, β, γ, D0, and D10) of the gamma irradiation effect. The dose-proportional effect, linear-quadratic dose-effect relationship, and Sotolongo et al. models showed a good fit to the survival data of Bacillus cereus and Escherichia coli exposed to radiation. For Bacillus cereus, the dose-proportional effect and linear-quadratic dose-effect models showed similar lethal doses (0.935 and 0.844 kGy), while the Sotolongo et al. model showed a lower lethal dose (0.406 kGy), indicating greater radiation efficacy. In Escherichia coli, the dose-proportional effect and linear-quadratic dose-effect models also showed similar lethal doses (0.716 and 0.745 kGy), and the Sotolongo et al. model showed a lower lethal dose (0.319 kGy), indicating greater efficacy. Tsallis entropy-based models are suitable for describing membrane behavior and biochemical changes in bacteria exposed to gamma radiation.