The absorbance at wavelength of 378 nm (OD378) of algal cells at
different growth stages at 7, 14, 21, 28, 35, 50, 65, 80 and 95 days and
the algal cell dry weight, observation of the microalgal growth process
by extending the culture cycle: Algal cells are in a phase of growth
adaptation from 0 to 14 days and grow more slowly; After entering the
second phase of logarithmic growth, the growth of algal cells was more
rapid, and both the absorbance OD378 and the dry weight of algal cells
showed a steady upward trend, the algal cells entered the third phase of
decay at 65 to 95 days, and the OD378 and the algal cell dry weight
gradually declined to the demise of the algal cells.