(i) normal nitrogen supply with light (i.e. normal growth condition);
(ii) normal nitrogen supply with dark;
(iii) nitrogen deprivation with light;
(iv) nitrogen deprivation with dark.
The results from table 1 suggested that the highest PHB accumulation under acetate supply was obtained under
(iiii): nitrogen deprivation with dark.
For example, Oscillatoria okeni and Chlorogloea fritschii produced PHB only 0.05-3.13 % w/cdw under the conditions (i), (ii) or (iii), but it accumulated PHB up to ….. z % w/w DW under the condition
(iv): nitrogen deprivation with dark.