Abstract
Microplastics (MPs) are prevalent pollutants in environments that are colonized by various groups of microbes. Fungi are considered among the most efficient microbial degraders of MPs because they produce salient enzymes and can survive on recalcitrant compounds with limited nutrients. While most studies have focused on the occurrence of MPs in wastewater treatment systems, MP degradation in fresh water and wastewater is generally poorly understood. Therefore, the current study included the isolation of some genera of fungi from the Tigris River water environment that have the ability to degrade MPs in both natural and artificial environments utilizing synthetic media. Using weight loss measurements, Fourier transform infrared spectroscopy (FTIR) was used to identify the chemical structure of the plastic polymers, and scanning electron microscopy (SEM) was used to determine the size and morphology of the microplastics and the degree of plastic consumed by the aquatic fungus. The biodegradation of high-density polyethylene (HDPE) and polystyrene (PS) by the aquatic fungus Aspergillus carbonarius and Eurotium sp. was also examined. Overall, Aspergillus carbonarius and Eurotium sp. were able to degrade HDPE more efficiently than PS without requiring any prior microplastic treatment. Therefore, the ability of fungi to degrade MPs was confirmed by weight loss, FTIR, and SEM data. Therefore, the results indicate that the isolated fungus has a promising future for polymer breakdown in both artificial and natural environments. Investigating the long-term impacts and gaining a deeper knowledge of the mechanisms of microplastic disintegration should be the main goals of future research.