Potential of filamentous fungi for the biodegradation of low-density polyethylene
Restricted (Penn State Only)
Author:
Peritz, Kellien
Area of Honors:
Biorenewable Systems
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Josephine Wee, Thesis Supervisor Stephen C Chmely, Thesis Honors Advisor
Keywords:
Filamentous fungi Polyethylene SEM FTIR Biodegradation
Abstract:
The ubiquity of plastic throughout the last century has caused plastic waste to accumulate so vastly that no country has been able to rid its nation of plastic pollution. Due to the molecular structure of plastic polymers, these materials do not decompose in nature. This honors thesis reviews past research and conducts preliminary research to investigate leveraging fungi for the biodegradation of one type of plastic, low-density polyethylene (LDPE). The literature review compares and evaluates the experimental designs and results of seven studies researching fungal biodegradation of LDPE. Five of the seven studies conducted thorough experiments and analyses, with evidence supporting biodegradation. The last two papers provided insufficient evidence of biodegradation, due to the limitations of the experimental designs and analyses. The preliminary research studied the synergistic effects between pretreatment and fungal treatment on the degradation of LDPE film. Pretreatments included nitric acid, ultraviolet radiation, hydrogen peroxide, and heat; fungal strains included Phanerochaete chrysosporium and Aspergillus niger. Scanning electron microscopy and Fourier-transform infrared spectroscopy were used to assess changes in surface morphology and functional groups, respectively, of the LDPE samples. Results of these analyses concluded that LDPE film pretreated with nitric acid and inoculated with A. niger showed the most degradation.
