Biodegradation of Polyester Polyurethane by Endophytic Fungi

TLDR

Bioremediation relies on diverse microbial metabolisms to degrade pollutants, making biological processes a key strategy for waste reduction. The study sought to identify endophytic fungi capable of degrading polyester polyurethane by screening a diverse collection. Researchers screened several dozen endophytic fungi for their ability to break down PUR, assessing degradation in solid and liquid suspensions. Multiple isolates, notably two Pestalotiopsis microspora strains, efficiently degraded PUR, grew on it as sole carbon source under aerobic and anaerobic conditions, and exhibited serine hydrolase activity, indicating endophytes as a promising source for bioremediation.

Abstract

ABSTRACT Bioremediation is an important approach to waste reduction that relies on biological processes to break down a variety of pollutants. This is made possible by the vast metabolic diversity of the microbial world. To explore this diversity for the breakdown of plastic, we screened several dozen endophytic fungi for their ability to degrade the synthetic polymer polyester polyurethane (PUR). Several organisms demonstrated the ability to efficiently degrade PUR in both solid and liquid suspensions. Particularly robust activity was observed among several isolates in the genus Pestalotiopsis , although it was not a universal feature of this genus. Two Pestalotiopsis microspora isolates were uniquely able to grow on PUR as the sole carbon source under both aerobic and anaerobic conditions. Molecular characterization of this activity suggests that a serine hydrolase is responsible for degradation of PUR. The broad distribution of activity observed and the unprecedented case of anaerobic growth using PUR as the sole carbon source suggest that endophytes are a promising source of biodiversity from which to screen for metabolic properties useful for bioremediation.