Grantee Research Project Results
2022 Progress Report: Biodegradation of PFASs from Groundwater and Soil
EPA Grant Number: SU840169Title: Biodegradation of PFASs from Groundwater and Soil
Investigators: Goel, Ramesh , Dentinger, Bryn , Diaz, Ruby , Nallappan, Namratha
Current Investigators: Goel, Ramesh , Dentinger, Bryn , Diaz, Ruby
Institution: University of Utah
EPA Project Officer: Spatz, Kyle
Phase: I
Project Period: December 1, 2020 through November 30, 2021 (Extended to November 30, 2023)
Project Period Covered by this Report: December 1, 2021 through November 30,2022
Project Amount: $24,978
RFA: P3 Awards: A National Student Design Competition Focusing on People, Prosperity and the Planet (2020) RFA Text | Recipients Lists
Research Category: P3 Awards , P3 Challenge Area - Safe and Sustainable Water Resources
Objective:
The bacteria Streptomyces cattleya (SC) is known for the capacity to synthesize fluorinated metabolites and the bacteria bacillus amyloliquefaciens (BA) is known for the capacity to produce secondary metabolites that promote plant growth. White rot fungi are known for their capacity to mineralize lignin, a complex organic polymer difficult to biodegrade, in this experiment the species Pleurotus ostreatus (PO), Phanerochaete chrysosporium (PC), and Ganoderma lucidum (GL). were used in the co-cultivation experiments.
1. The objective of this project was to determine if the co-cultivation of bacteria and fungi could be used to achieve biodegradation of PFAS such as PFOA and PFOS. No intermediate compounds will be measured during the experiments, only PFOA, PFOS, and fluoride concentrations.
2. Investigate under different medium conditions if enzymes produced by the co-cultivation of fungi and bacteria can mineralize PFAS.
3. Evaluate if the enzyme manganese peroxidase produced by P. chrysosporium can be used to break down the bond between C-F in PFAS such as PFOA.
4. Evaluate the groundwater quality from a site exposed to long-term exposure to PFAS and determine if free fluoride is present in the groundwater.
Progress Summary:
The initial experimental part of this project included co-cultivation of the two bacteria species with the three different white rot fungi species. The fungi-bacteria co-cultivation combination that showed an enhancement on the growth of the white rot fungi was GL with SC and this combination was used for the subsequent PFAS biodegradation experiments.
The biodegradation of per and polyfluoroalkyl substances (PFAS) such as
perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) were evaluated using cocultivation of the bacteria Streptomyces cattleya (SC) and the white rot fungi Ganoderma lucidum (GL). The analytical data showed that no mineralization took place using the co-cultivated bacteria and fungi. All the experiments were performed in liquid media. Polypropylene containers with polypropylene caps were used for all the batch experiments and some adsorption of PFAS was observed during the qualification of PFAS using HPLC/MS/MS. The adsorption of PFAS to polypropylene have also being observed by other researchers.
The premise that the enzymes generated during co-cultivation could mineralize PFAS was further evaluated using the enzyme manganese peroxidase. This enzyme was produced by the white rot fungi Phanerochaete chrysosporium (PC) and it is known for the capacity to degrade lignin, organic pollutants and dyes. Batch tests were used to determine the capacity of the enzyme to mineralize PFOA. The chemical compound 1-hydroxy benzotriazole (HBT) was used as a mediator during the experiment and hydrogen peroxide (H2O2) was used to activate the enzyme.
The batch experiments were run at a temperature of 27.5 oC and mixed at 130 rpm. The experimental results did not show any mineralization of PFOA. Fluoride was used as an indicator for mineralization of PFAS. None of the experiments showed fluoride concentrations. Negative controls were added to all the experiments.
Supplemental Keywords:
Manganese Peroxidase, Pleurotus ostreatus, Ganoderma lucidum, Phanerochaete chrysosporium; Bacillus amyloliquefaciens, Streptomyces cattleya, biodegradationProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.