Biotransformation of Phthalate Plasticizers and Bisphenol A by Marine-Derived, Freshwater, and Terrestrial Fungi

Abstract

Phthalate esters (PEs, Phthalates) are environmentally ubiquitous as a result of their extensive use as plasticizers and additives in diverse consumer products. Considerable concern relates to their reported xenoestrogenicity and consequently, microbial-based attenuation of environmental PE concentrations is of interest to combat harmful downstream effects. Fungal PE catabolism has received less attention than that by bacteria, and particularly fungi dwelling within aquatic environments remain largely overlooked in this respect. We have compared the biocatalytic and biosorptive removal rates of din -butyl phthalate (DBP) and diethyl phthalate (DEP), chosen to represent two environmentally prominent PEs of differing structure and hydrophobicity, by marine-, freshwater-, and terrestrial-derived fungal strains. Bisphenol A, both an extensively used plastic additive and prominent environmental xenoestrogen, was included as a reference compound due to its well-documented fungal degradation. Partial pathways of DBP metabolization by the ecophysiologically diverse asco-and basidiomycete strains tested were proposed with the help of UPLC-QTOF-MS analysis. Species specific biochemical reaction steps contributing to DBP metabolism were also observed. The involved reactions include initial cytochrome P450-dependent monohydroxylations of DBP with subsequent further oxidation of related metabolites, de-esterification via either hydrolytic cleavage or cytochrome P450-dependent oxidative O-dealkylation, transesterification, and demethylation steps-finally yielding phthalic acid as a central intermediate in all pathways. Due to the involvement of ecophysiologically and phylogenetically diverse filamentous and yeast-like fungi native to marine, freshwater, and terrestrial habitats the results of this study outline an environmentally ubiquitous pathway for the biocatalytic breakdown of plastic additives. Beyond previous research into fungal PE metabolism which emphasizes hydrolytic de-esterification as the primary catabolic step, a prominent role of cytochrome P450 monooxygenase-catalyzed reactions is established.

Exploring Potent Fungal Isolates from Sanitary Landfill Soil for In Vitro Degradation of Dibutyl Phthalate

“…On the 15th day, SDBP4 degraded 99.34% of the DBP present in the medium, while SDBP6 could degrade only 29.44%, which showed distinct variability in DBP assimilation among the isolates. A study including different fungi: Ascocoryne sp., Phoma sp., Clavariopsis aquatica and Paradendryphiella arenariae also exhibited differences in the consumption of DBP, which supports our results [ 41 ]. Thus, SDBP4 was further identified at the molecular level due to its highest degradation capacity.…”

“…The medium was supplemented with DBP (50 mg L −1 ) from stock made with equal volumes of DBP and ethanol. Tween 80 (400 mg L −1 ) was added to the medium to improve DBP’s solubility [ 41 , 42 ]. The same medium composition was used for further degradation experiments.…”

Filamentous fungi for sustainable remediation of pharmaceutical compounds, heavy metal and oil hydrocarbons

“…It was shown that the detoxification of penicillin side-chain precursors might depend on microsomal GST in P. chrysogenum (Emri et al, 2003). Fungal cytochromes can catalase a lot of different reactions, which enables them to degrade xenobiotics and pollutants (Syed et al, 2013;Chen et al, 2019;Wang et al, 2019;Carstens et al, 2020;Hu et al, 2020). Fungal enzymes, isolated from Basidiomycetes and Ascomycetes, show high ability of plastic waste biodegradation.…”

Enhanced esterase activity during the degradation of dibutyl phthalate by Fusarium species in liquid fermentation

“…These microorganisms may enhance pollutant degradation in phthalate-contaminated environments. Several investigations have revealed that fungal species such as Polyporus brumalis , Ganoderma lucidum , Trametes versicolor , Phlebia tremellosa , Neurospora sithopila , P. ostreatus , Phoma sp., Stropharia rugosoannulata , Ascocoryn e sp., Puccinia arenariae are phthalate-degrading organisms (Hwang et al, 2008 ; Kim et al, 2008 ; Lee et al, 2007 ; Kim & Song, 2009 ; Ahuactzin-Pérez et al., 2018a , 2018b ; Carstens et al, 2020 ; González-Márquez et al, 2019 ; González-Márquez et al, 2020 ; Hwang et al, 2012 ; Liao et al, 2012 ; Luo et al, 2012 ; Sánchez, 2021 ; Sánchez-Sánchez & Sánchez, 2019 ). In particular, fungi such as Fusarium species have been reported to degrade phthalates due to their esterase production.…”