Copper-induced Production of Laccases for Lignin Depolymerisation and Micropollutant Degradation by Laccase-mediator Systems

Contaminants deriving from human activities represent a constantly growing threat to our environment and have a direct impact on plant and animal health. To alleviate this ecological imbalance, biocatalysis offers a green and sustainable alternative to conventional chemical processes. Due to their broad specificity, laccases are enzymes possessing excellent potential for synthetic biotransformations in various fields as well as for the degradation of organic contaminants. Herein, we produced laccases in submerged cultures of P. ostreatus and T. versicolor in three different media. The fungi/medium combination leading to the highest enzymatic activity was malt extract (2%) + yeast extract (3%) + glucose (0.8%). Laccase production was further increased by supplementing this medium with different concentrations of Cu2+, which also provided a better understanding of the induction effect. Additionally, we disclose preliminary results on the interaction of laccases with mediators (ABTS and violuric acid - VA) for two main applications: lignin depolymerisation with guaiacylglycerol-β-guaiacyl ether (GBG) as lignin model and micropollutant degradation with Remazol Brilliant Blue (RBB) as enzymatic bioremediation model. Promising results were achieved using VA to increase depolymerization of GBG dimer and to enhance RBB decolorisation.

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Applicability of Recombinant Laccases From the White-Rot Fungus Obba rivulosa for Mediator-Promoted Oxidation of Biorefinery Lignin at Low pH

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2020.604497 ◽

2020 ◽

Vol 8 ◽

Author(s):

Jussi Kontro ◽

Riku Maltari ◽

Joona Mikkilä ◽

Mika Kähkönen ◽

Miia R. Mäkelä ◽

...

Keyword(s):

White Rot ◽

White Rot Fungus ◽

Lignin Biodegradation ◽

Reaction Conditions ◽

Tempo Oxidation ◽

Chemical Treatments ◽

Mediator Systems ◽

Phenolic Components ◽

Lignin Model ◽

Rich Side

Utilization of lignin-rich side streams has been a focus of intensive studies recently. Combining biocatalytic methods with chemical treatments is a promising approach for sustainable modification of lignocellulosic waste streams. Laccases are catalysts in lignin biodegradation with proven applicability in industrial scale. Laccases directly oxidize lignin phenolic components, and their functional range can be expanded using low-molecular-weight compounds as mediators to include non-phenolic lignin structures. In this work, we studied in detail recombinant laccases from the selectively lignin-degrading white-rot fungus Obba rivulosa for their properties and evaluated their potential as industrial biocatalysts for the modification of wood lignin and lignin-like compounds. We screened and optimized various laccase mediator systems (LMSs) using lignin model compounds and applied the optimized reaction conditions to biorefinery-sourced technical lignin. In the presence of both N–OH-type and phenolic mediators, the O. rivulosa laccases were shown to selectively oxidize lignin in acidic reaction conditions, where a cosolvent is needed to enhance lignin solubility. In comparison to catalytic iron(III)–(2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) oxidation systems, the syringyl-type lignin units were preferred in mediated biocatalytic oxidation systems.

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A Newly Isolated Wood-rot Fungus for Laccase Production in Submerged Cultures

BioResources ◽

10.15376/biores.8.1.1385-1397 ◽

2013 ◽

Vol 8 (1) ◽

Cited By ~ 5

Author(s):

Kai Fu ◽

Shiyu Fu ◽

Huaiyu Zhan ◽

Pandeng Zhou ◽

Mengru Liu ◽

...

Keyword(s):

Laccase Production ◽

Submerged Cultures

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Degradation of Aflatoxin B1 and Zearalenone by Bacterial and Fungal Laccases in Presence of Structurally Defined Chemicals and Complex Natural Mediators

Toxins ◽

10.3390/toxins11100609 ◽

2019 ◽

Vol 11 (10) ◽

pp. 609 ◽

Cited By ~ 6

Author(s):

Xiaolu Wang ◽

Yingguo Bai ◽

Huoqing Huang ◽

Tao Tu ◽

Yuan Wang ◽

...

Keyword(s):

Aflatoxin B1 ◽

Animal Health ◽

Chemical Compounds ◽

Fungal Laccases ◽

Cucumis Sativus L ◽

Cota Laccase ◽

Mediator Systems ◽

Food And Feed ◽

Methyl Syringate ◽

Shed Light

Aflatoxin B1 (AFB1) and zearalenone (ZEN) exert deleterious effects to human and animal health. In this study, the ability of a CotA laccase from Bacillus subtilis (BsCotA) to degrade these two mycotoxins was first investigated. Among the nine structurally defined chemical compounds, methyl syringate was the most efficient mediator assisting BsCotA to degrade AFB1 (98.0%) and ZEN (100.0%). BsCotA could also use plant extracts, including the Epimedium brevicornu, Cucumis sativus L., Lavandula angustifolia, and Schizonepeta tenuifolia extracts to degrade AFB1 and ZEN. Using hydra and BLYES as indicators, it was demonstrated that the degraded products of AFB1 and ZEN using the laccase/mediator systems were detoxified. Finally, a laccase of fungal origin was also able to degrade AFB1 and ZEN in the presence of the discovered mediators. The findings shed light on the possibility of using laccases and a mediator, particularly a natural plant-derived complex mediator, to simultaneously degrade AFB1 and ZEN contaminants in food and feed.

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Improving laccase production by employing different lignocellulosic wastes in submerged cultures of Trametes versicolor

Bioresource Technology ◽

10.1016/s0960-8524(01)00176-6 ◽

2002 ◽

Vol 82 (2) ◽

pp. 109-113 ◽

Cited By ~ 90

Author(s):

M Lorenzo ◽

D Moldes ◽

S Rodrı́guez Couto ◽

A Sanromán

Keyword(s):

Trametes Versicolor ◽

Laccase Production ◽

Submerged Cultures ◽

Lignocellulosic Wastes

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Lignin-Modifying Enzymes of the White Rot Basidiomycete Ganoderma lucidum

Applied and Environmental Microbiology ◽

10.1128/aem.65.12.5307-5313.1999 ◽

1999 ◽

Vol 65 (12) ◽

pp. 5307-5313 ◽

Cited By ~ 116

Author(s):

Trevor M. D’Souza ◽

Carlos S. Merritt ◽

C. Adinarayana Reddy

Keyword(s):

Ganoderma Lucidum ◽

Laccase Activity ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Mesh Size ◽

Syringic Acid ◽

White Rot ◽

White Rot Fungus ◽

Laccase Production ◽

Malt Extract

ABSTRACT Ganoderma lucidum, a white rot basidiomycete widely distributed worldwide, was studied for the production of the lignin-modifying enzymes laccase, manganese-dependent peroxidase (MnP), and lignin peroxidase (LiP). Laccase levels observed in high-nitrogen (HN; 24 mM N) shaken cultures were much greater than those seen in low-nitrogen (2.4 mM N), malt extract, or wood-grown cultures and those reported for most other white rot fungi to date. Laccase production was readily seen in cultures grown with pine or poplar (100-mesh-size ground wood) as the sole carbon and energy source. Cultures containing both pine and poplar showed 5- to 10-fold-higher levels of laccase than cultures containing pine or poplar alone. Since syringyl units are structural components important in poplar lignin and other hardwoods but much less so in pine lignin and other softwoods, pine cultures were supplemented with syringic acid, and this resulted in laccase levels comparable to those seen in pine-plus-poplar cultures. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of concentrated extracellular culture fluid from HN cultures showed two laccase activity bands (M r of 40,000 and 66,000), whereas isoelectric focusing revealed five major laccase activity bands with estimated pIs of 3.0, 4.25, 4.5, 4.8, and 5.1. Low levels of MnP activity (∼100 U/liter) were detected in poplar-grown cultures but not in cultures grown with pine, with pine plus syringic acid, or in HN medium. No LiP activity was seen in any of the media tested; however, probing the genomic DNA with the LiP cDNA (CLG4) from the white rot fungus Phanerochaete chrysosporium showed distinct hybridization bands suggesting the presence oflip-like sequences in G. lucidum.

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SKRINING KAPANG Aspergillus spp. PENGHASIL AFLATOKSIN PADA JAGUNG PIPILAN DI DAERAH BEKASI, JAWA BARAT

AL-Kauniyah Jurnal Biologi ◽

10.15408/kauniyah.v11i2.6961 ◽

2018 ◽

Vol 11 (2) ◽

pp. 151-162

Author(s):

Dalia Sukmawati ◽

Priyo Wahyudi ◽

Sri Rahayu ◽

Moersilah Moersilah ◽

Tri Handayani ◽

...

Keyword(s):

Aspergillus Flavus ◽

Aspergillus Parasiticus ◽

Animal Health ◽

Positive Control ◽

Selective Medium ◽

Agricultural Products ◽

Malt Extract Agar ◽

Confirmatory Test ◽

Malt Extract ◽

Extract Agar

AbstrakAflatoksin merupakan senyawa metabolit sekunder dari kapang Aspergillus flavus dan Aspergillus parasiticus yang dapat mengontaminasi bahan pangan atau pakan sehingga berbahaya bagi kesehatan hewan dan manusia. Kontaminasi kapang penghasil aflatoksin banyak ditemukan pada bahan pangan dan pakan yang berasal dari produk pertanian. Jagung merupakan salah satu produk pertanian yang mudah terkontaminasi oleh kapang penghasil aflatoksin. Penelitian ini bertujuan untuk memperoleh isolat kapang Aspergillus spp. penghasil aflatoksin pada jagung pipilan yang dijual di sekitar Bekasi, Jawa Barat. Isolasi kapang dilakukan menggunakan metode dilution plating pada medium Dichloran-Glycerol. Hasil penelitian memperoleh 12 isolat kapang, dengan warna koloni hijau (J1, J2, J3, J4, J5, J6, J7, J9, J10, J12), hitam (J11), dan jingga (J8). Identifikasi dilakukan dengan cara mengamati morfologi kapang secara makroskopik dan mikroskopik pada medium Malt Extract Agar. Isolat kapang yang diduga memiliki kemiripan dengan A. flavus berjumlah 6 isolat, yaitu J1, J2, J4, J6, J10, dan J12. Selanjutnya dilakukan uji konfirmasi menggunakan medium selektif Aspergillus flavus dan parasiticus Agar. Terdapat 2 isolat kapang, yaitu J1 dan J4, yang menunjukkan pigmentasi sebalik koloni berwarna pada medium selektif AFPA. Isolat kapang yang ditemukan pada jagung pipilan diharapkan dapat memberikan informasi kepada petani dan peternak mengenai jenis kapang yang dapat menyebabkan kontaminasi pada jagung, sehingga mereka dapat menjaga dan meningkatkan kualitas jagung untuk mengurangi kerugian dalam bidang ekonomi dan kesehatan.Abstract Aflatoxin is a secondary metabolite secreted by the mold Aspergillus flavus and Aspergillus parasiticus that may contaminate food or feed so harmful to human and animal health. Contamination of aflatoxin-producing mold is commonly found in food and feed which derived from agricultural products. Corn is one of the agricultural products that are easily contaminated by aflatoxin-producing mold. The study aims to isolate the aflatoxin-producing mold Aspergillus spp. in stripped corn vend around Bekasi, West Java. The isolation was conducted by using the method of dilution plating on Dichloran-Glycerol medium. The study obtained 12 isolates of mold, with green colony color (J1, J2, J3, J4, J5, J6, J7, J9, J10, J12), black (J11), and jingga (J8). Identification was conducted by observing the morphology of mold on Malt Extract Agar macroscopically and microscopically. The isolates that allegedly have similarities to A. flavus are J1, J2, J4, J6, J10, and J12. Furthermore, a confirmatory test was preceed by using a selective medium of Aspergillus flavus and parasiticus agar. There are 2 isolates of molds, J1 and J4, which showed yellowish jingga pigmentation like the positive control of A. flavus. The isolates of mold found in the stripped corn may provide information to farmers and breeders about the type of mold that can cause contamination in corn, so that they can anticipate in advance and improve the quality of the corn to reduce losses in economic and health perspectives.

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The role of the global cryosphere in the fate of organic contaminants

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-16923-2012 ◽

2012 ◽

Vol 12 (7) ◽

pp. 16923-17000 ◽

Cited By ~ 4

Author(s):

A. M. Grannas ◽

C. Bogdal ◽

K. J. Hageman ◽

C. Halsall ◽

T. Harner ◽

...

Keyword(s):

Climate Change ◽

Sea Ice ◽

Time Scales ◽

Organic Pollutants ◽

Organic Contaminants ◽

Chemical Processes ◽

Ice Caps ◽

Current State ◽

Physical And Chemical

Abstract. The cryosphere is an important component of global organic contaminant cycles. Snow is an efficient scavenger of atmospheric organic pollutants while a seasonal snowpack, sea ice, glaciers and ice caps are contaminant reservoirs on time scales ranging from days to millennia. Important physical and chemical processes occurring in the various cryospheric compartments impact contaminant cycling and fate. A variety of interactions and feedbacks also occur within the cryospheric system, most of which are susceptible to perturbations due to climate change. In this article, we review the current state of knowledge regarding the transport and processing of organic contaminants in the global cryosphere with an emphasis on the role of a changing climate.

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Effects of nitrogen from different sources on mycelial biomass and polysaccharide production and pellet morphology in submerged cultures of Grifola frondosa

BioResources ◽

10.15376/biores.16.2.2937-2952 ◽

2021 ◽

Vol 16 (2) ◽

pp. 2937-2952

Author(s):

Yi-Cheng Wang ◽

Fang-Yi Lin ◽

Tai-Hao Hsu

Keyword(s):

Nitrogen Source ◽

Yeast Extract ◽

Nitrogen Sources ◽

Grifola Frondosa ◽

Extracellular Polysaccharides ◽

Malt Extract ◽

Mycelial Biomass ◽

Submerged Cultures ◽

Polysaccharide Production ◽

Pellet Morphology

The effects of nitrogen in the medium on the production of mycelial biomass, extracellular polysaccharides (EPS), and intracellular polysaccharides (IPS) was investigated in submerged cultures of Grifola frondosa. In addition, the effects on pellet morphology were examined. The maximum production levels of mycelial biomass (2.32 g/L), EPS (1.58 g/L), and IPS (29.1 mg/L) were obtained when the nitrogen sources in the medium were yeast extract, malt extract, and peptone, respectively. Using yeast extract as the nitrogen source yielded the maximum mycelial biomass, and morphological characterization revealed a composition of 47% large pellets (fraction L), 20% small pellets (fraction S), and 33% adhesive mycelia (fraction A). The maximum circularity value and the minimum roughness value of the pellets were observed using yeast extract cultures. Both the compactness (0.53) and circularity (0.15) of the pellets were the lowest among the seven types of nitrogen sources, but the roughness (2.86) was the highest in malt extract, which was the nitrogen source that resulted in maximum polysaccharide production. The results revealed that the production levels of mycelial biomass, EPS, and IPS of G. frondosa were associated with changes in pellet morphology due to the source of nitrogen in the medium.

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High production of ligninolytic enzymes from white rot fungi in cereal bran liquid medium

Canadian Journal of Microbiology ◽

10.1139/w98-233 ◽

1999 ◽

Vol 45 (7) ◽

pp. 627-631 ◽

Cited By ~ 35

Author(s):

M A Pickard ◽

H Vandertol ◽

R Roman ◽

R Vazquez-Duhalt

Keyword(s):

Manganese Peroxidase ◽

White Rot Fungi ◽

Alcohol Oxidase ◽

Ligninolytic Enzymes ◽

Veratryl Alcohol ◽

White Rot ◽

Laccase Production ◽

Good Growth ◽

Malt Extract ◽

Cereal Bran

White rot fungi from the University of Alberta Mold Herbarium, identified as able to degrade aromatics from a study of PCB metabolism, were examined for production of ligninolytic enzymes. Production of lignin peroxidase, manganese peroxidase, laccase, and veratryl alcohol oxidase were monitored during growth in different media. Good growth but low enzyme production occurred in a glucose - malt extract - yeast extract medium. Media containing 2% cereal bran in 60 mM phosphate buffer supported high levels of laccase production, up to 13 000 U/L in Coriolopsis gallica UAMH 8260 and manganese peroxidase activity up to 1100 U/L in Bjerkandera adusta UAMH 8258. Cereal bran media supported higher laccase production than 2,5-xylidine and higher manganese peroxidase production than a medium containing manganous ion plus veratryl alcohol.Key words: cereal bran, laccase, manganese peroxidase, white rot fungi.

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