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Updated: Jun 21, 2026
10:22
Designed for Molecular Recycling: A Lignin-Derived Semi-aromatic Biobased Polymer
Published on: November 30, 2020
Systematic optimization and characterization of bacterial depolymerization of poly(ethylene terephthalate) plastics
Apoorva Sherigar1,2, Ritu Raval1, Abdul Ajees Abdul Salam3
1Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India.
Scientific Reports
|June 19, 2026
Summary
This study optimized poly(ethylene terephthalate) (PET) biodepolymerization using Glutamicibacter mysorens ASR14, achieving 75.6% degradation. This microbial approach offers a sustainable solution for PET waste management and bioremediation.
Area of Science:
- Microbiology
- Environmental Science
- Biotechnology
Background:
- Poly(ethylene terephthalate) (PET) pollution is a significant environmental concern.
- Biodepolymerization using microorganisms presents a sustainable solution for PET waste.
- Developing efficient microbial strains and optimizing degradation conditions are crucial.
Purpose of the Study:
- To optimize the biodepolymerization of PET using the mesophilic bacterium Glutamicibacter mysorens ASR14.
- To investigate the influence of various factors on PET degradation efficiency.
- To establish a comprehensive report on PET biodepolymerization using a whole-cell biocatalyst.
Main Methods:
- Isolation and identification of Glutamicibacter mysorens ASR14 from a dumpyard.
- Experimental design using JMP software for initial screening (20 trials).
- Response Surface Methodology (RSM) with Central Composite Design (CCD) for optimization (25 trials, 4 variables, 5 levels).
- Enzymatic assays to quantify esterase and lipase activity.
- Analytical characterization (surface erosion, crystallinity, terephthalic acid yield).
Main Results:
- Glutamicibacter mysorens ASR14 achieved 27.6% PET weight loss in 30 days under unoptimized conditions.
- Optimized conditions using RSM resulted in a maximum PET weight loss of 75.6% in 60 days.
- Significant esterase (5,690 U/mL) and lipase (962 U/mL) activities were confirmed.
- Analytical data showed surface erosion, reduced crystallinity, and high terephthalic acid yield.
Conclusions:
- Glutamicibacter mysorens ASR14 is a promising whole-cell biocatalyst for PET biodepolymerization.
- Process optimization significantly enhanced PET degradation efficiency (2.73-fold improvement).
- The study provides a foundation for developing scalable, green bioremediation strategies for PET waste.
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