Evaluation of parameters affecting recombinant PETase and MHETase activity in PET degradation
DOI:
https://doi.org/10.54939/1859-1043.j.mst.208.2025.98-104Keywords:
PETase; MHETase; Polyethylene terephthalate (PET); Biodegradation; Synthetic polymer.Abstract
PETase and MHETase are two enzymes catalyzing the degradation of polyethylene terephthalate (PET) into terephthalic acid (TPA) and ethylene glycol (EG), which are environmentally friendly and non-toxic. The application of these enzymes holds significant potential for treating plastic waste and advancing green technologies in environmental protection. In this study, several factors affecting enzyme activity, including buffer composition, temperature, and pH, were investigated. The optimal conditions for PETase and MHETase activity were identified as a temperature range of 30–40 °C, pH 8–9, and 100 mM sodium phosphate buffer. Under these conditions, the recombinant enzymes hydrolyzed commercial PET film within 7 days of treatment, resulting in a significant change in the PET surface morphology and thereby demonstrating the effectiveness of PETase and MHETase in PET film cleavage. These results highlight the potential of two recombinant enzymes for plastic waste treatment.
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