Effect of Selenate on Viability and Selenomethionine Accumulation of Chlorella sorokiniana Grown in Batch Culture
Figure 1
Growth curves of Chlorella sorokiniana culture with 40 mg·L−1 of selenate (a) and control culture (no selenate) (b). Data are given as mean values ± S.D. of the means. Both experimental data of population numbers and data calculated from logistic mathematical model fit are graphically presented in Figures 1(a) and 1(b). Model equation used is , where is the initial cell density at time zero, is the maximal density that cell population can theoretically reach in the indefinite time, is and the maximal culture growth rate (h−1), and is cultivation time (day). Figure 1(c) presents concentration-response relationship between maximal growth rates from logistic growth models and selenate concentrations in medium. Concentration-response curve was fitted to the 2 parameter log-logistic model (Hill’s model) using open source software “R statistical package.” To predict presumptions were made that concentration of 100 mg·L−1 selenate corresponds to the maximal (100%) growth inhibition, while zero inhibition corresponds to Se-free culture growth rate. Obtained value form the log-logistic model curve was 45 mg·L−1 of selenate.
