Fig. 5

Effect of storage temperature and period on degradation after lyophilization. (a) Polyhydroxybutyrate (PHB) degradation pattern was assessed at various temperatures. The storage temperature associated with the greatest degradation yield was 25 ℃. (b) The preservation of degradation activity was compared at different temperatures; the degradation yield was preserved at over 90% at most temperatures, except for − 80 ℃. (c) Polyhydroxybutyrate (PHB) degradation activity was assessed after various storage periods. When samples were stored for 28 d, no major differences were observed compared with control cells. (d) Degradation activity was not affected by the storage period. Data shown are the means and standard deviataions of duplicate experiments