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This study focuses on using Casuarina equisetifolia biomass for pilot-scale glucose oxidase production from Aspergillus niger and its application in the removal of trace organic contaminants (TrOCs) from municipal wastewater through the bio-Fenton oxidation. The cost of glucose oxidase was 0.005 $/U, including the optimum production parameters, 10% biomass, 7% sucrose, 1% peptone, and 3% CaCO 3 at 96 h with an enzyme activity of 670 U/mL. Optimized conditions for H 2 O 2 were 1 M glucose, 100 U/mL glucose oxidase, and 120 mins of incubation, resulting in 544.3 mg/L H 2 O 2 . Thus, H 2 O 2 produced under these conditions lead to bio-Fenton oxidation resulting in the removal of 36-92% of nine TrOCs in municipal wastewater at pH 7.0 in 360 mins. Therefore, this work establishes the cost-effective glucose oxidase-producing H 2 O 2 as an attractive bioremediating agent to enhance the removal of TrOCs in wastewater at neutral pH., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

This research work aims to valorize lignocellulosic biorefinery sludge with genetically engineered Trichoderma atroviride for simultaneous removal of organic contaminants, fermentation inhibitors, and lignocellulolytic enzyme cocktail production. Upon analysis, three phenolic compounds (42.6 ± 3.6 μg/g), two polycyclic aromatic hydrocarbons (0.42 ± 0.06 μg/g) and five fermentation inhibitors (2.5 ± 0.3 mg/g) were detected in the sludge. Bioaugmentation of sludge with 72 h-old T. atroviride (5%) results in the production of cellulase (21 U/g), xylanase (84 U/g), laccase (20 U/g), lignin peroxidase (14 U/g) and aryl alcohol oxidase (116 U/g), along with the concomitant removal of organic contaminants (phenol, 2, 4-dinitrophenol, pentchlorophenol, phenanthrene, benzo(a)pyrene) and fermentation inhibitors (furfural, 5-hydroxymethylfurfural, levulinic acid, ferulic acid, and catechol). Subsequently, the enrichment of sludge with nutrients and rhamnolipids enhanced the enzyme production by 5-6-fold and resulted in the removal of 85-95% of organic contaminants and fermentation inhibitors, which constitutes an eco-friendly process., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Polycyclic aromatic hydrocarbons (PAH) and pharmaceutical compounds (PhC) are xenobiotics present in many saline wastewaters. Although fungi are known for their ability to remove xenobiotics, the potential of halophilic fungi to degrade highly persistent pollutants was not yet investigated. The use of two halophilic fungi, Aspergillus sydowii and Aspergillus destruens, for the elimination of PAH and PhC at saline conditions was studied. In saline synthetic medium both fungi used benzo-α-pyrene and phenanthrene as sole carbon source and removed over 90% of both PAH, A. sydowii due to biodegradation and A. destruens to bioadsorption. They removed 100% of a mixture of fifteen PAH in saline biorefinery wastewater. Test using Cucumis sativus demonstrated that wastewater treated with the two fungi lowered considerably the phytotoxicity. This study is the first demonstration that ascomycetous halophilic fungi, in contrast to other fungi (and in particular basidiomycetes) can be used for mycotreatments under salinity conditions., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The present study investigated the applicability of a laccase based bioprocess for the treatment of a mixture containing 13 selected pharmaceuticals. To do so, laccase was immobilized as cross-linked enzyme aggregates (MAC-CLEAs) on amine functionalized magnetic nanoparticles using chitosan/1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDAC) as the cross-linking system. The activity recovery of laccase reached 61.4% under the optimal conditions of MAC-CLEAs formation. The latter exhibited enhanced storage stability over one year at 4°C and showed better temperature resistance compared to its soluble counterpart. The biocatalysts were properly recycled and the catalytic activity recovery was good even after a hundred and fifty batch reactions. Complete removal of pharmaceuticals like acetaminophen, diclofenac, mefenamic acid, atenolol and epoxy carbamazepine and partial removal of fenofibrate, diazepam, trimethoprim, and ketoprofen by laccase was achieved within 12h of incubation, whereas efficient removal of indometacin required the presence of mediator., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

An evaluation of the efficiency of the White-rot fungi (WRF) Trametes hirsuta to remove multi-classes pharmaceutical active compounds (17 PhACs) at low and environmentally realistic concentrations (20-500 ng L(-1)) was performed. The importance of biosorption over enzymatic activity on PhACs removal was also evaluated. Results highlight the importance to consider environmentally relevant PhACs concentrations while evaluating the removal capacities of WRF in wastewaters treatment processes, as PhACs concentration strongly influence both the enzymatic activity profile and the removal efficiency. Results also show that under tested experimental conditions, laccase was the only active extracellular lignin modifying enzyme and that biosorption and possibly intracellular enzymes also contribute to the removal of some PhACs., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Laccase and laccase-based cross-linked enzyme aggregates (CLEAs) were stabilized through the formation of a surrounding polymeric network made of chitosan and 3-aminopropyltriethoxysilane. The thermoresistance of the resulting enzyme polymer engineered structures of laccase (EPES-lac) and CLEAs (EPES-CLEA) were more than 30 times higher than that of free laccase and CLEAs at pH 3 and 40 °C. The EPES showed higher residual activity than the unmodified biocatalysts against chaotropic salts (up to 10 times), EDTA (up to 5 times), methanol (up to 15 times) and acetone (up to 20 times). The Michaelis-Menten kinetic parameters revealed that the affinity for 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) has doubled for the EPES-lac and EPES CLEA compared to their unmodified forms. The EPES-lac structures acted optimally at pH 4 and their activity was nearly temperature-independent, while the laccase activity of EPES-CLEA was optimal at pH 4 and 60 °C. Globally, the EPES have shown significantly improved properties which make them attractive candidate for the development of laccase-based applications., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A commercial laccase from Trametes versicolor was conjugated with biopolymer chitosan using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) as the cross-linking agent. Laccase-chitosan conjugation strategies were tested using different molar ratios of glucosamine monomer/protein with different molar excess ratios of EDC relative to laccase. Immobilization techniques were developed to improve the stability against thermal and chemical denaturation, storage and reusability of this biocatalyst. The conjugation resulted in a solid biocatalyst with an apparent laccase activity of ±626 U/g, 12 and 60 folds higher in the conjugation efficiency of biocatalyst relative to the immobilized and free laccase activity respectively when compared with zero EDC/laccase ratio used in conjugation solution. The conjugated laccases formed successfully eliminated the emerging pollutant triclosan (TCS) from aqueous solutions, having a higher potential to transform TCS than free laccase. UPLC-QTOF results indicate the formation of TCS oligomers. Furthermore, they are the first evidence of direct dechlorination of TCS mediated by the oxidative action of laccases., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Laccase from the white rot fungus strain Coriolopsis polyzona was immobilized covalently on the diatomaceous earth support Celite R-633 using different strategies. A first methodology involved the sequential activation of the support surface with gamma-aminopropyltriethoxysilane followed by the reaction of the functionalized surface with glutaraldehyde (GLU) or glyoxal (GLY) and the immobilization of laccase on the activated surface. Another strategy tested the simultaneous internal cross-linking of the protein with GLU or GLY and the immobilization of the laccase on the silanized surface. Finally, these two strategies were modified to test the impact of the concomitant addition of bovine serum albumin (BSA) as a stabilizing agent during the immobilization steps. The highest laccase activity and the greatest degree of activity recovery (tested using 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) as the substrate) were achieved by the sequential immobilization procedure using GLU as the cross-linking agent. The solid catalysts featuring internal cross-linking of the protein showed significantly higher stability against several denaturants. The Michaelis-Menten kinetic parameters with respect to ABTS revealed a higher affinity for this substrate in the case of the sequential procedure compared to the simultaneous approach. The biocatalyst formed using GLU in the sequential procedure was applied in a packed bed reactor for the continuous treatment of 5 mg l(-1) solutions of the endocrine disrupting chemicals (EDCs) nonylphenol (NP), bisphenol A (BPA) and triclosan (TCS) through repeated batch treatments. All of these EDCs could be eliminated at a contact time of less than 200 min by using, respectively, 3.75 units (U) of laccase activity for BPA and TCS and 1.88 U for NP. These performances of elimination were maintained over five consecutive treatment cycles using the same biocatalyst. This system could also remove these EDCs from 100 mg l(-1) solutions. The Michaelis-Menten kinetic parameters with respect to these chemicals showed a decreasing affinity of the solid biocatalyst for NP, TCS and BPA in that order.