3. Results and discussion
In the present study, the effect of NaCl addition on the growth
and PHA production by C. necator was evaluated.
3.1. Effect of NaCl at different concentrations on the growth of
C. necator
PHA yield not only depends on the amount of PHA stored within
the bacterial cell but it is also attributed to the number of cells accumulating
PHA. Therefore, it was essential to achieve high cell numbers
before the bacteria started accumulating PHA. The initial
increase in OD (Tables 1a–1e) and CDW was mainly due to cell
growth (Fig. 1). It was evident from CDW measurements, that
bacteria were able to have a reasonable growth of above 5 g/l CDW
by 24 h in all the cases except for salt concentrations of 12 g/l and
15 g/l NaCl, which resulted in much lower CDW of 1.9 g/l and 2 g/l
at 24 h, respectively (Fig. 1). Also, theCDWfor the fermentation with