Researchers have discovered a fungus capable of degrading plastic in the North Pacific garbage patch. This discovery could open new avenues for combating oceanic plastic pollution.
For several years, scientists have been identifying microorganisms capable of consuming certain types of plastics. The latest discovery is the fungus
Parengyodontium album. Living in the ocean, this fungus shows a particular aptitude for degrading polyethylene, the most common type of plastic found in oceans, used notably for water bottles and shopping bags.
Parengyodontium album was identified among the microorganisms living in the North Pacific garbage patch, also known as the "plastic continent." By analyzing this waste, researchers discovered that this fungus fragments polyethylene by mineralizing it into carbon dioxide (CO2) at a rate of 0.05% per day. Although this rate may seem low, it is significant for a microorganism.
Photodegradation by ultraviolet (UV) rays is necessary to prepare the work of the fungi. Indeed, exposure to sunlight partially decomposes the plastic, thus facilitating its degradation by
P. album. However, this method is only applicable to plastics floating on the ocean surface.
Despite this promising discovery, the solution does not lie solely in these fungi. The amount of plastic waste in the oceans is immense, with about 88,000 tons (80,000 tonnes) in the North Pacific garbage patch alone. Furthermore, not all types of plastics are affected. Only plastics exposed to UV, primarily polyethylene, can be degraded by this process.
It is conceivable that other species of fungi or even more numerous bacteria also contribute to the degradation of plastics, including those on the ocean floor. This adaptation of microorganisms to plastic pollution demonstrates their ability to colonize new ecological niches created by human activity.
Thus, although
Parengyodontium album is not a miracle solution for eliminating plastics from the oceans, this discovery highlights the importance of continuing research on the degradation capabilities of microorganisms. At the same time, reducing the use of plastics remains essential to preserve marine ecosystems.
Author of the article: Cédric DEPOND