where X refers to total biomass concentration in the culture,
cell + PHA (units g L−1).
Parameter d refers to the maximum biomass concentration
in the culture, cell + PHA (units g L−1). In contrast, a refers the
difference between initial and final biomass concentration (units
g L−1).
Parameter b refers to the lag phase time during growth kinetics
in hours, and c is a shape factor related with the exponential
growth phase time, in hours.