Fig. 1. Optical density of Escherichia coli in water at 600 nm versus time

Fig. 2. Normalized spectra of Escherichia coli suspension at different growth stages

Fig. 3. Changes of average size and the internal average size of Escherichia coli cells in water versus time

Fig. 4. Micrographs of Escherichia coli cells at different growth stages. (a) 1 h; (b) 2 h; (c) 3 h; (d) 4 h; (e) 5 h; (f) 6 h; (g) 7 h

Fig. 5. Bacteria concentration versus time

Fig. 6. Absorption coefficients of total nucleic acid, chromophoric amino acids, and dipicolinic acid (DPA) in microorganism[19]

Fig. 7. (a) Total content of nucleotides in suspensions of Escherichia coli versus time; (b) average content of nucleotides per cell of Escherichia coli versus time