Here in the TIME sector of Brevard High School, semesters may end, but the science is never done. As the quarter has drawn to an end, final tests were being performed in HAS‘s corner of the TIME room. It had been a close competition between the fungi M. fragilis and T. asperellum the whole semester to see which species was the superior lead contamination remediator. Previously, results from the precipitate and fluorescence tests were promising but did not give an indication to which species remediated significantly more. We were sure the actual biofilter test would prove a winner, so we broke out the filter. So for each species, we got our dried fungi biomass, loaded the filter, and ran the lead water through. We used the fluorometer to measure the lead remaining and calculated the percentages remediated by each species. Unfortunately, we weren’t able to declare a significantly better bioremediator from the test… on the other hand, M. fragilis removed 97% of the lead and T. asperellum removed 96% of the lead present. Not bad stats for a prototype lead filter run on fungi.
Here in the TIME room the HAS (Hannah, Aidan, Spradlin) group has been working hard… punching fungi chips. We’re ready to begin our trial testing to determine which fungi we will be using in our in-depth heavy metal remediation tests. To narrow down to the two fungi we will use, our trial will consist of using a precipitate test to measure the amount of lead that the different species of our isolated fungi are able to absorb. Currently, we have three potential species of Trichoderma (viride, asperellum, and hamatum) and M. fragilis. We will be running the tests to narrow down out samples to one species of Trichoderma, in addition to M. fragilis. The Trichoderma species that absorbs the highest concentrations of lead will be the fungi that ‘competes’ against the M. fragilis, which was used in last year’s mycoremediation project.
So where do the fungi chips come in? Well, to control the variables in our precipitate test, we wanted uniform dried fungal biomass to work with. The question was, how to get this consistency in the material from dried sheets of fungi. The solution? A hole puncher! We spent quite some time filling weigh boats with .5g of round hole punched fungi, enough to run three trials.. But we are now ready to begin the trials. Time to see which species is the superior lead absorber.
It’s always a good sign when you actually find what you’re searching for in an experiment, correct? Yes! After averting a possible crisis from contamination of a green mold, we finally (after weeks of plating and transferring, described in our previous blog) plated each of our isolated strains of fungi on guaiacol agars. We found the results that we’d been hoping for, three of our 27 samples have tested positive for the lignin degrading enzymes, ligninases. Soon, we will be able to perform PCR on our successful ligninase producing fungi and find out what we’re dealing with!
Their explorations are in the hot pursuit of local species of lignicolous fungi, or fungi that degrade lignin. Their studies of these extraordinary microorganisms have just begun, yet they have already been captivated by their preliminary findings dealing with fungi isolation. Who knew bleach would inhibit bacterial growth, but allow the fungi to propagate?!