REMOVAL OF MIXED HEAVY METALS BY MANGANESE-OXIDIZING FUNGI FOR BIOREMEDIATION OF CONTAMINATED WATER IN OKLAHOMA

Critical water sources to local communities across Oklahoma are being contaminated by toxic heavy metal ions where anthropogenic activities like mining and oil/gas exploration are present. High concentrations of heavy metal ions including Mn, Cd, Co, Ni, Pb, and Zn present at these locations are harmful to human health and agriculture. Higher levels of Ca ions tend to be present due to the composition of the surrounding rock. Along with these metals and other ions, microbes (e.g., fungi, bacteria) can be found at these impacted sites and could help remove metal ions from polluted water. Our research focuses on Mn-oxidizing fungi’s ability to remove Mn, Co, Ni, and Cd from affected water sources. By utilizing the fungi for bioremediation, we can provide a cost-effective and eco-friendly strategy to remove these metals from the water for future re-use of metals, agriculture, and the safety of local residents.

Ion concentrations of Mn, Co, Ni, Cd, and Ca have been determined by previously collected water samples from impacted areas. Various strains of Mn-oxidizing fungi have been isolated from impacted waters and will be inoculated in synthetic media containing nutrients needed for growth in the lab. After inoculating the fungi, we will examine the growth rate of biomass and removal of Mn (II) to determine the ability of the fungi to grow and oxidize. Experiments based on normal and elevated metal ion concentrations will be conducted on the fungi to analyze ion removal with co-concentration and combinations of Mn, Co, Ni, and Cd. Additional experiments adding Ca to the synthetic media along with the nutrients to simulate natural water conditions will be done to analyze how Ca affects the removal of the heavy metals. The Mn oxides will be characterized using an electron microscope (SEM/TEM), X-ray Diffraction (XRD), and X-ray absorption spectroscopy (XAS). The water samples will be analyzed using UV-Vis spectroscopy and ICP-MS or ICP-OES to quantify ion concentrations.

The results of this research will be crucial to the production of an efficient and cost-effective system for the bioremediation of metal-contaminated water throughout Oklahoma. By utilizing Mn-oxidizing fungi, we will be able to remove various co-concentrations of mixed heavy metal ions from any water source in Oklahoma affected by toxic heavy metal pollution.