As shown in Fig. 1, the linear polynomial fit of OD686 absorbance
versus MA density was determined with the slope of
1.4615 108, y-intercept of 2.0359 104 and R2-value of
0.9975. The linear polynomial fit was valid for the MA cell density
range up to 5 107 cell mL1. Absorbance of EM did not show
obvious peak in the absorbance spectrum analysis. Hence, OD600
was selected yielding standard calibration curve of OD600
absorbance versus EM density. The linear polynomial fit yield the
slope of 4.83206 1010, y-intercept of 0.0004 and R2-value of
0.9992