Isolation and Characterization of PHB-Producing Bacteria

The producing PHB bacterial strain was isolated from a soil sample collected from the botanic garden of Skikda University by performing serial dilutions. Pure, viable colonies were then grown in a mineral salt medium (MSM) [20] (link) to which 2% glucose and 10 g of agar were added; the mixture was then incubated for 48 h at 37 °C. The PHB-producing colonies were detected by adding an ethanolic solution of 3% Sudan Black B (C29H24N6 224-087, Sigma). The Sudan Black B positive isolate was tested for its ability to produce PHB in the agar MSM medium [20] (link) and added 2% of carob molasses instead of glucose. The bacterial strain was spotted onto the MSM agar medium and incubated at 37 °C for 48 h. The bacterial colonies were colored with an ethanolic solution of 3% Sudan Black B (C29H24N6 224-087, Sigma) to confirm its ability to produce PHB [21] (link).