Polystyrene microplastic biodegradation by filamentous fungi isolated from mangrove and Apicum

• Grant number: 21/11074-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2022
• End date: December 31, 2022
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Cristiane Angélica Ottoni
• Grantee: Letícia Fontes Gama
• Host Institution: Instituto de Biociências (IB-CLP). Universidade Estadual Paulista (UNESP). Campus Experimental do Litoral Paulista. São Vicente , SP, Brazil

Abstract

Microplastics (MPs) are considered as emerging contaminants and have a size of 5 mm or less in diameter. These include polyethylene terephthalate (PET), polyethylene (PE), high density polyethylene (HDPE), low density polyethylene (LDPE), polyvinyl chloride (PVC), polypropylene, polystyrene (PS), and miscellaneous plastics (including polycarbonate, poly, fiberglass, nylon, among other polymers). Removing MPs from the marine environment is more difficult due to their size, wide distribution, and complex composition. In the last decade, many studies have investigated the distribution of MPs and related adverse effects on this and other ecosystems, while few studies have attempted to identify an optimal strategy to eliminate or mitigate their effects. In the process of exploring methods to decrease MP pollution, it has been observed MPs can be degraded by some microorganisms (MO), although they can persist in the environment and resist degradation. Among the MO capable of biodegrading MPs, filamentous fungi (Ff) are the most promising, as they play a crucial role in the degradation and mineralization of various pollutants. The biodegradation processes of MPs by Ff can be evaluated through microbial growth and/or changes in the polymer itself. However, to date few Ff have been isolated, identified, and the interactions between these organisms and MPs have not been fully explained. Among the most explored Ff's in the last years, the ones from extremophilic environments deserve to be highlighted. They are adapted to more adverse conditions in comparison to those detected in terrestrial environments, such as high pressure, low temperature, oligotrophic nutrients, and high salinity. Therefore, the possibility of using organisms from this environment represents a promising alternative which meets the 2030 Agenda for Sustainable Development goals: (13) Take urgent action to combat climate change and its impacts, and (14) Conservation and sustainable use of the oceans, seas, and marine resources for sustainable development. Therefore, the present project aims to prospect Ff from Mangrove and Apicum with the ability to biodegrade the microplastic PS. This is a fundamental step for the subsequent analysis of the enzymes involved in the biodegradation process of this xenobiotic and recalcitrant compound.(AU)