Stochastic simulation of growth curves of Acidithiobacillus ferrooxidans

Abstract

To reveal the low growth rate of Acidithiobacillus ferrooxidans, a stochastic growth model was proposed to analyze growth curves of these bacteria in a batch culture. An algorithm was applied to simulate the bacteria population during lag and exponential phase. The results show that the model moderately fits the experimental data. Further, the mean growth constant (K) of growth curves is obtained by fitting the logarithm of the simulating population data versus the generation numbers with the different initial population number (N₀) and initial mean activity of population (A₀). When N₀ is 300 and 700 respectively, the discrepancy of K value is only 0.91%, however, A₀ is 0.34 and 0.38 respectively, the discrepancy of K value is 19.53%. It suggests that the effect of A₀ on the lag phase exceeds N₀, though both parameters could shorten the lag phase by increasing their values.

Keywords

Acidithiobacillus ferrooxidans / stochastic simulation / growth curves / lag phase

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