Optimization of poly (3-hydroxybutyrate) production by recombinant Escherichia coli using an experimental screening...

The negative effects of synthetic plastics on ecosystems and human health have increased interest in environmentally friendly and biodegradable bioplastics. Among bioplastics, polyhydroxyalkanoates (PHAs) stand out due to their biodegradability, biocompatibility, and thermal processability. Thus, there are several studies focused on bioplastics production with a high yield by using agricultural wastes as carbon source in order to meet the industrial needs. This study aimed to produce poly (3-hydroxybutyrate) (P3HB), one of the PHAs, by the recombinant Escherichia coli Rosetta pQEAL1124 strain using dried raisin waste (RW) as a carbon source. The optimization of physicochemical parameters affecting the production process were identified. For the optimization of P3HB production, conditions providing the maximum predicted response and a maximum desirability value of 0.86 were found to be 7.03 g/L RW, 2.46 g/L tryptone, and 194 rpm. The maximum P3HB yield was achieved as 490 mg/L under these conditions with a purity level of 86%. The Young's modulus value of the extracted P3HB was found to be 170 MPa. This study provides a valuable contribution to sustainable waste valorization and P3HB production by presenting an innovative perspective on environmentally friendly and sustainable production processes.