Entitled Biodegradation of Polyester Polyurethane by Endophytic Fungi, the study aimed to find new potential plant sources of bioremediation, also known as the use of microorganisms to biodegrade and eliminate pollutants that otherwise persist in the environment. Several students attending Yale's annual Rainforest Expedition and Laboratory course collected various samples from the
Of all the microorganisms tested, nine of the most active came from the Pestalotiopsis genus, which represents the first time endophytic fungi have been identified as having bioremediation properties. It was discovered that a key enzyme in this fungal genus known as taxol is responsible for eating away PUR, and that this "extracellular, secreted and diffusible" substance diffuses to "a significant distance," which means it has huge potential for large-scale PUR cleanup efforts.
"This is the first study that demonstrates PUR degradation by endophytic fungi," wrote the authors in their discussion. "The broad distribution of activity suggests that endophytes might be a promising source of biodiversity in which to test for activities important for bioremediation."
Taxol, which is also derived from the bark of Pacific Yew trees, happens to be the same enzyme used in conventional medicine to treat cancer patients. Though it is now administered to patients in synthetic, patented forms created by drug companies that now produce it using genetically-modified (GM) bacterium, taxol in its natural form has demonstrable anti-cancer properties, and has been used in native cultures by herbalists to treat disease naturally.
As interesting as this new discovery about taxol's PUR bioremediation properties may be, it is more than likely that, should this substance ever be used to eat plastics on an industrial scale, it will likely be derived from synthetic, patented sources rather than from natural sources. But as it currently stands, the Pestalotiopsis genus of endophytic fungi appear to be nature's built-in remedy for helping to keep the environment clean and toxin-free, as it already appears to be performing this function in rainforests around the world.
Sources for this article include: