Rapid degradation of poly(butylene succinate-co-butylene terephthalate)s by microbial communities at high-temperature

Poly(butylene succinate-co-butylene terephthalate)s (PBST) is a partially biobased biodegradable plastic, prepared by polymerizing polybutylene succinate (PBS) and polybutylene terephthalate (PBT). Though confirmed to be biodegradable, research on its degradation, particularly at high temperatures, is limited. In this study, microbial communities obtained from diverse environmental samples were used to degrade PBST with various PBT mole ratios for 60 days at 50 degree celsius. The degradation rate decreased as PBT mole ratio increased. PBST with less than 32.5% PBT showed a degradation rate exceeding 0.7 mg/cm(2)/day. Degradation began at the plastic surface, involving ester bond cleavage and increased hydrophilicity. Higher PBT content led to greater bacterial species richness and varying bacterial communities. Notably, Paenibacillus, Pigmentiphaga, Blastocatella, and Bacillus were abundant in the high-temperature degradation microbial community, suggesting their importance in rapid PBST degradation. This study affirms PBST's biodegradability and offers insights for establishing rapid degradation methods.