Therefore, it is possible that at 3.5 and 6.5 g/l NaCl concentrations, the PHA degradation was slower due to the decreased activity of β-hydroxybutyrate dehydrogenase and hence significant PHA degradation did start until after 36–38 h. But at higher salt concentrations of 9, 12 and 15 g/l NaCl, significant PHA degradation occurred after 26–28 h. The study of the enzyme activity influenced by the salt concentration is an aim for further research work.