The document discusses the production of the biological macromolecule polyhydroxybutyrate (PHB) by Bacillus subtilis isolated from sewage, noting that optimal production conditions were found to be 48 hours of incubation at 37°C and pH 7.5. Experiments were also conducted to develop low-cost production media using fruit peel extract and sugarcane industrial waste, finding reasonable PHB yields. Characterization of the produced PHB was carried out using FTIR and NMR analysis.