White-rot Fungus Bjerkandera Adusta Research Articles

Oxidative degradation and detoxification of multiple mycotoxins using a dye-decolorizing peroxidase from the white-rot fungus Bjerkandera adusta

Mycotoxins are widely present from cereal crops to food products, posing a significant risk to food safety and causing serious health and economic losses. Therefore, it is imperative to develop a sustainable and efficient detoxification strategy to address mycotoxin contamination. Herein, a dye-decolorizing peroxidase, BaDyP, from the white-rot fungus Bjerkandera adusta was successfully expressed as a soluble form in Escherichia coli with the help of molecular chaperones. Purified recombinant BaDyP could efficiently degrade multiple mycotoxins including aflatoxin B1, zearalenone, and deoxynivalenol in the presence of mediators such as Mn2+ or 1-HBT. Meanwhile, their degradation products were identified using UPLC-MS/MS, including AFB1-diol, AFQ1, 15-OH-ZEN, HZEN, and C15H18O8. Furthermore, cell survival tests exhibited a significant reduction in the biological toxicity of these degradation products. These findings indicate that the use of dye-decolorizing peroxidase could be a promising approach for the effective removal of multiple mycotoxins in cereal crops and food products.

Sulfadiazine degradation by Bjerkandera adusta DH0817 at low temperatures and its cold-adaptation mechanisms

The prolonged period of low temperatures in northern China poses a significant challenge to the bioremediation of antibiotic pollution. This study reports that a white-rot fungus Bjerkandera adusta DH0817, isolated from a poultry farm in Liaoning Province, can remove 60 % of SDZ within 20 days at 10℃ and reduce the biotoxicity of SDZ. Six degradation pathways were proposed. SDZ biodegradation was primarily driven by cytochrome P450. Transcriptome analysis revealed that DH0817 upregulated genes associated with cell membrane, transcription factors and soluble sugars in response to low temperatures. Subsequently, genes associated with fatty acid, proteins and enzymes were upregulated to remove SDZ at low temperatures. This study provides valuable microbial resources and serves as a theoretical reference for addressing antibiotic pollution in livestock and poultry farms under low temperature conditions.

Fungal lyophilisates as catalysts for organic synthesis: Preparative oxidations with the white-rot fungus Bjerkandera adusta

A clean and selective “on-water-on-air” oxidation of primary alcohols to the corresponding aldehydes with mycelium lyophilisates of the non-toxic white-rot fungus Bjerkandera adusta was developed. The biocatalytic protocol is simple and the catalyst is readily accessible as a powder, which could be stored at least for 7 months without changes of activity. The catalytic activity of the fungus is associated with the presence of aryl-alcohol oxidase, that was isolated from the lyophilisate and characterised. Remarkably, a dichotomy in the fungal reactivity was observed, as the corresponding growing cultures catalyse the reverse process, selectively reducing aldehydes to the corresponding alcohols. Enzymatic oxidations by B. adusta are an excellent non-toxic alternative to metal-mediated oxidations in the lab with potential in food, beverage, cosmetic, and pharmaceutical industries, as it tolerates many functional groups.

Remoción de colorantes reactivos empleando el hongo Bjerkandera adusta

La manufactura de textiles para Colombia representa una importante actividad económica, con una participación en exportaciones del 6% y genera ventas de productos no tradicionales alrededor de un 13%. Esta industria utiliza alrededor del 15% del total del agua empleada para labores industriales, desechando alrededor de 170.000 toneladas de aguas residuales por año en Colombia. Entre los impactos ambientales que genera el sector, se destaca la contaminación sobre aguas causada en las etapas de tintura; esta se da principalmente debido a que los colorantes empleados tienen rangos de fijación entre el 65% y el 80%. En la etapa inicial de esta investigación, se determinaron los parámetros de caracterización del agua según el decreto 0631 de 2015 a los efluentes provenientes del proceso de teñido; se tuvieron en cuenta parámetros como: alcalinidad, dureza, DBO, DQO, conductividad, sólidos y oxígeno disuelto. Se realizaron revisiones bibliográficas con el fin de establecer el potencial de diferentes tipos de microorganismos, los cuales abarcan desde bacterias aerobias, anaerobias y hongos de pudrición blanca. En la ejecución de esta investigación se trabajará con el hongo de la pudrición blanca B. adusta, debido a que es capaz de degradar sustratos complejos a través de un sistema enzimático específico para cada familia de colorantes. Posteriormente se realizó la selección del medio de cultivo que más promoviera el proceso de degradación de los colorantes reactivos; los medios evaluados fueron el Kirk, Zouari-Mechichi y el Park-Robinson. De los tres, el que tuvo mejores resultados fue el medio Park Robinson. Por último, se evaluó la remoción de colorantes en aguas residuales sintéticas. Las remociones obtenidas para la familia de colorantes reactivos de la familia Bezaktiv (colorantes vinilsulfónicos) fueron: 30% para el Bezaktiv azul V-2B 133, para el Bezaktiv amarillo V-5 GL 91% y para el Bezaktiv rojo V-5B 74 %.

Gamma irradiation assisted fungal degradation of the polypropylene/biomass composites

Abstract White-rot fungus Bjerkandera adusta has been tested for its ability to degrade some biocomposites materials based on polypropylene and biomass (Eucalyptus globulus, pine cones, and Brassica rapa). γ-irradiation was applied to initiate the degradation of relatively inert polypropylene matrix. The degradation process has been studied by scanning electron microscopy, atomic force microscopy, infrared spectroscopy, contact angle measurements, rheological and chemiluminescence tests. These analyses showed that the polypropylene/biomass composites properties are worsen under the action of the selected microorganism. The formation of cracks and scrap particles over the entire matrix surface and the decrease of the complex viscosity values, as well as the dynamic moduli of gamma irradiated PP/biomass composite and exposed to Bjerkandera adusta fungus, indicate fungal efficiency in composite degradation.

Differences in the secretion pattern of oxidoreductases from Bjerkandera adusta induced by a phenolic olive mill extract

The secretome of the white-rot fungus Bjerkandera adusta produced in synthetic Kirk medium was compared to that supplemented with an aqueous phenol-rich extract of dry olive mill residues (ADOR). Distinct changes in the protein composition of oxidoreductases, namely diverse class-II peroxidases and aryl alcohol oxidases were found.In the ADOR-supplemented medium (ASC), 157 distinct proteins were identified by the secretome analysis, whereas only 59 of them were identified without ADOR supplementation (Kirk medium culture; KM). Proteome analysis indicated that the number of peroxidases produced in ASC was more than doubled (from 4 to 11) compared to KM. Two short manganese peroxidases (MnP1 and MnP6) and one versatile peroxidase (VP1) represented 29% of the relative abundance (NSAF) in ASC. Two of them (MnP1 and VP1) were also detected in KM at a relative abundance (NSAF) of only 3%. Further peroxidases present in ASC were one lignin peroxidase (LiP2), one generic peroxidase (GP) and three dye-decolorizing peroxidases (DyPs). The relative abundance of DyPs and aryl alcohol oxidases (AAO) were lower in ASC in comparison to KM. In addition to peptide sequence analysis, the secretion of Mn2+-oxidizing peroxidases as well as AAOs were followed by enzyme measurement. The Mn2+-oxidizing activity increased nearly 30-fold (from 10 to 281Ul−1) after ADOR addition. Two enzymes responsible for that activity were successfully purified (BadVPI and BadVPII). To prove a potential involvement of these enzymes in the degradation of aromatic compounds, BadVPI was tested for its ability to degrade the recalcitrant dehydrogenated polymer (DHP, synthetic lignin). These results show that natural phenol-rich materials act as secretome-stimulating additives. Applying these substances enables us to investigate fungal degradation and detoxification processes and gives more insight into the complexity of fungal secretomes, e.g. of white-rot fungi.

Depolymerization and solubilization of chemically pretreated powder river basin subbituminous coal by manganese peroxidase (MnP) from Bjerkandera adusta

This study evaluated the influence of four chemical pretreatment agents (HNO3, catalyzed H2O2, KMnO4, NaOH) on the subsequent enzymatic conversion of subbituminous coal by a fungal manganese peroxidase (MnP) produced by the agaric white-rot fungus Bjerkandera adusta. The effects of the combined chemical and enzymatic treatments were analyzed by high performance size exclusion chromatography (HPSEC) and 3-dimensional excitation emission matrix fluorescence spectroscopy (3D-EEM). The nature of pretreatment agents and their applied concentrations had significant impacts on subsequent enzymatic conversion of coal. The 3D-EEM spectroscopic analysis provided new insight into the nature of the depolymerized and released coal constituents. Using the fluorescence spectra, it was possible to distinguish among humic-like, fulvic acid-like, protein-like, and aromatic/PAH-like substances. The fungal enzyme MnP had little effect on the untreated coal controls. Nitric acid (HNO3) was the most effective pretreatment agent as indicated by the HPSEC profiles, followed by catalyzed H2O2 and KMnO4. Low molecular weight aromatic fragments with sizes ranging from 1.1 to 6.2kDa were released by all of the pretreatment agents used in combination with MnP. For KMnO4 and HNO3 pretreated coal, all four EEM regions increased after MnP treatment (for example, 307.5/422nm and 232.5/426nm, and 340/448nm and 242.5/484nm for humic and fulvic acid-like fragments, respectively).

Study of mass transfer and biocatalyst stability for the enzymatic degradation of anthracene in a two-phase partitioning bioreactor

In this study the optimal experimental conditions for the degradation of a polycyclic aromatic hydrocarbon in an enzymatic two-phase partitioning bioreactor (TPPB) were investigated. The immiscible organic phase was comprised of silicone oil, acting as a pollutant reservoir for anthracene. This compound underwent degradation by the enzyme versatile peroxidase (VP) produced by the white-rot fungus Bjerkandera adusta. Mass transfer coefficients ( k L a) and enzymatic deactivation constants ( k D) were determined in the TPPB system. The effects of operational parameters such as solvent viscosity (10, 20 and 50 cSt), agitation rate (200, 250 and 300 rpm) and addition of the non-ionic surfactant Triton X-100 (below its critical micelle concentration, CMC) on the mass transfer and enzymatic decay were investigated. It was ascertained that there was superior enzymatic stability at high values of viscosity. The addition of surfactant below CMC displayed the dual benefit of increasing mass transfer of the substrate fivefold from the organic to aqueous phase whilst also creating a protecting effect upon VP. Optimized conditions led to an 88% oxidation of anthracene after 38 h.

Expression of soluble versatile peroxidase of Bjerkandera adusta in Escherichia coli

Versatile peroxidase from white rot fungus Bjerkandera adusta was over-expressed in a soluble form in Escherichia coli. In the constructed enzyme model based on the selected gene from B. adusta, the active sites for oxidation of Mn 2+ ions and for oxidation of aromatic substrates were identified, both characteristic for versatile peroxidase. For over-expression of the recombinant enzyme different host strains, media formulations, growth temperatures, and fusion partners were tested. With the bacterial strain BL21(DE3)pLysS cultivated at 25 °C in auto-induction medium and presence of heme, a soluble peroxidase with incorporated heme and activity against different substrates was obtained. By exploiting an appropriate expression system and providing suitable culture conditions, the recombinant fungal peroxidases in soluble form can be produced in bacteria.

Selenium Induces Manganese-dependent Peroxidase Production by the White-Rot Fungus Bjerkandera adusta (Willdenow) P. Karsten

In this study, selenium (Se) induction of the ligninolytic enzyme manganese-dependent peroxidase (MnP) production, and the effects on the oxidative state in the white-rot fungus Bjerkandera adusta (Willdenow) P. Karsten were demonstrated. Low concentration of Se (0.5 mM) caused up to a twofold increase in MnP production (0.81 +/- 0.05 U/ml) when compared to control (0.39 +/- 0.07 U/ml), whereas higher concentrations of Se (200 mM) inhibited (0.03 +/- 0.01 U/ml) MnP production. Addition of high concentration of Se also caused up to a twofold increase in lipid peroxidation levels. These results demonstrate for the first time that Se may induce or reduce MnP production and lipid peroxidation levels which play a significant role in lignin degradation by white-rot fungi.

Enhanced Production of Manganese-Peroxidase by the White-Rot Fungus Bjerkandera Adusta using Media Engineering

ABSTRACTManganese peroxidase (MnP) production by the white-rot fungus Bjerkandera adusta (Willdenow) P. Karsten was enhanced significantly through media engineering, using the statistical modeling approach called response surface methodology. Both fractional factorial and central composite designs were applied in the optimization studies to evaluate the effect of mycological peptone, KH2PO4, MnSO4, and glucose on MnP production. With a view to simultaneously reducing the number of experiments and obtaining more information on the mutual interactions between the variables, 24-1 fractional factorial and full 22 central composite design led to 12 sets of experiments. When the optimized amounts were used, MnP activity obtained was increased approximately 600% (from 0.40 U ml−1 to 2.41 U ml−1). The effect of central composite design coupled with fractional factorial approach was more profound on the increase of the MnP activity compared to that of fractional factorial approach alone. Our response surface methodological results showed for the first time that peptone but not Mn2+ was the most important ingredient affecting the level of MnP production by the fungus B. adusta. The significant increase in MnP activity via response surface methodology demonstrates the potential of this recent isolate to be considered as a good source of MnP for industrial applications.

Bioremediation of HCH present in soil by the white-rot fungus Bjerkandera adusta in a slurry batch bioreactor

In the soil remediation process, the hydrophobic characteristics of pollutants and their affinity for soil matrix may be responsible for mass transfer limitations. The degradation of hexachlorocyclohexane (HCH) isomers present in a spiked soil by the white-rot Bjerkandera adusta was evaluated in a slurry system. Experiments in shaken flasks were performed to evaluate the action of the endogenous microflora, the adsorption of HCH on the fungal biomass and the potential synergic or antagonic actions between the microflora and the fungal biomass. The fungus significantly degraded the HCH isomers from the soil slurry in the following order: α≈ γ> δ> β-HCH. The degradation process was further scaled in a 5-l reactor, where the solid load and concentration of the pollutant in the soil were evaluated. At optimal conditions, 100 g soil l −1 and 100 mg total HCH l −1, maximal degradations of 94.5%, 78.5% and 66.1% were attained after 30 d for γ-, α- and δ-HCH isomers, respectively, representing between 1.7 and 3.1-fold the values obtained at small scale. These results indicate that minimising mass transfer resistances is a key factor for HCH degradation from soil.

Biodegradation of dibenzothiophene, fluoranthene, pyrene and chrysene in a soil slurry reactor by the white-rot fungus Bjerkandera sp. BOS55

Mass transfer phenomena can be an important constraint of the soil remediation process. With the goal of minimizing the mass transfer limitation, the degradation of four different PAHs by the white-rot fungus Bjerkandera adusta in a spiked marsh soil was evaluated in a slurry system. Key factors affecting the oxidation of PAHs with different chemical structure (two, three and four aromatic rings) were investigated. These included inoculum preparation, glucose concentration and synergic or antagonic actions between endogenous microflora and fungal culture. It was demonstrated that the fungus was able to grow and degrade the pollutants in a slurry phase stirred tank reactor. There was no significant improved effect on the degradation when the treatment was performed in presence of soil microflora. The system attained high PAH degradations, around 30 mg PAH/kg soil, after 30 days of operation under optimal conditions.

Decolorization of high concentrations of synthetic dyes by the white rot fungus Bjerkandera adusta strain CCBAS 232

Among thirty different basidiomycetes screened, Bjerkandera adusta strain CCBAS 232, Phanerochaete chrysosporium strain CCBAS 571 and Pleurotus ostreatus strain CCBAS 473 showed the best decolorization properties. B. adusta strain CCBAS 232 was able to decolorize a number of chemically different synthetic dyes (Orange G, Amaranth, Remazol Brilliant Blue R, Cu-phthalocyanine and Poly R-478) at relatively high concentrations of 2–4 g L −1 both on solid and in liquid medium. This strain also grew easily and produced biomass under these conditions. Unlike P. chrysosporium and P. ostreatus, B. adusta was able to efficiently decolorize all tested dyes. These properties and also a good ligninolytic enzyme production predetermine B. adusta strain CCBAS 232 for biotechnological applications.

Microbial conversion of daunomycin wastes in unsteril soil inoculated with Bjerkandera adusta R59

Effect of cooperation between native soil microorganisms and white-rot fungus Bjerkandera adusta R59 on degradation of daunomycin post-production wastes in soil was described. Pure cultures of B. adusta R59 strain were capable to decolorize and decompose that cytostatic xenobiotic in liquid media. Presence of R59 strain in studied daunomycin waste/soil systems increased the rate of the antibiotic conversion. The markers of that process were changes of waste biomass or daunomycin concentration (in pulp) and phenolics level and peroxidase activity (in effluent). It was shown that daunomycin in the wastes may be metabolized even up to 20% of its initial concentration. This effect was conjugated with the propagation of native soil microorganisms (microfungi and bacteria) more significant than in parallel system without R59 strain.

Biosynthetic pathway for halogenated methoxybenzaldehydes in the white rot fungus Bjerkandera adusta

Through experiments with fluoro-labelled phenylalanine, tyrosine and benzaldehyde, the biochemical pathway leading to the chlorinated methoxybenzaldehydes in the white rot fungus Bjerkandera adusta has now been verified. Cultures of this organism supplied with fluoro-labelled phenylalanine, tyrosine or benzaldehyde showed a bioconversion of these compounds into fluoro-4-methoxybenzaldehyde, fluoro-3-chloro-4-methoxybenzaldehyde and fluoro-3,5-dichloro-4-methoxybenzaldehyde. In addition fluoro-phenylalanine also yielded fluorobenzaldehyde. Fluorodichlorinated compounds were only detected in cultures supplied with ortho substituted fluoro-phenylalanine demonstrating a meta specific halogenation mechanism. These results are the first to give direct evidence of the involvement of both tyrosine and phenylalanine in the biosynthetic pathway of chloromethoxy substituted benzaldehydes in B. adusta and suggest a pathway for the biosynthesis of 3-chloro-4-methoxybenzaldehyde and 3,5-dichloro-4-methoxybenzaldehyde that proceeds either via phenylalanine through benzaldehyde and 4-methoxybenzaldehyde or via tyrosine through 4-methoxybenzaldehyde.

Mineralization of 14C-labelled synthetic lignin and extracellular enzyme activities of the wood-colonizing ascomycetes Xylaria hypoxylon and Xylaria polymorpha

Two wood-dwelling ascomycetes, Xylaria hypoxylon and Xylaria polymorpha, were isolated from rotting beech wood. Lignin degradation was studied following the mineralization of a synthetic [formula: see text]-labelled lignin in solid and liquid media. Approximately 9% of the synthetic lignin was mineralized by X. polymorpha during the growth on beech wood meal, and the major fraction (65.5%) was polymerized into water- and dioxan-insoluble material. Both fungi produced laccase (up to 1,200 U l-1) in an agitated complex medium based on tomato juice; peroxidase activity (<80 U l-1) was only detected for X. polymorpha in soybean meal suspension. The enzymatic attack of X. polymorpha on beech wood resulted in the formation of three fractions of water-soluble lignocellulose fragments with molecular masses of 200, 30 (major fraction) and 3 kDa, as demonstrated by high-performance size exclusion chromatography. This fragment pattern differs considerably from that of the white-rot fungus Bjerkandera adusta, which preferentially released smaller lignocellulose fragments (0.8 kDa). The finding that X. polymorpha produced large lignocellulose fragments, along with the fact that high levels of hydrolytic enzymes (esterase 630 U l-1, xylanase 120 U l-1) were detected, indicates the cleavage of bonds between the lignin and hemicellulose moieties.

Transformation of halogenated pesticides by versatile peroxidase from Bjerkandera adusta

Purified versatile peroxidase (VP) from the white rot fungus Bjerkandera adusta UAMH 8258 was used to study the transformation of several pesticides, including some as highly halogenated as the wood preservative pentachlorophenol (PCP). From the 13 pesticides assayed, dichlorophen, bromoxynil and PCP were transformed by VP in the presence and in the absence of manganese(II). For all the pesticides transformed, the activity was higher in the absence of Mn(II) at pH 3 than in the presence of Mn(II) at pH 4. Catalytic constants ( k cat) in the absence of Mn(II) at pH 4 were 194 and 409 min −1 for dichlorophen and bromoxynil, respectively. The K M values were 32 and 31 μM for the pesticides and 26 and 19 μM for the hydrogen peroxide, respectively. Analysis of reaction products by GC–MS showed the presence of 2,3,5,6-tetrachloroquinone among the products from pentachlorophenol oxidation, while the main product from dichlorophen was 4-chlorophenol-2,2′-methylenequinone. Several polymers were obtained from the peroxidase oxidation of bromoxynil. In all cases, we found dehalogenation reactions mediated by the versatile peroxidase. The importance and potential uses of the enzymatic transformation of these halogenated toxic compounds is discussed.

Sulfophthalimide as major metabolite formed from sulfonated phthalocyanine dyes by the white-rot fungus Bjerkandera adusta.

The reaction products formed during the decolorization of the sulfophthalocyanine textile dyes Reactive blue 15 (RB15) and Reactive blue 38 (RB38) by the white-rot fungus Bjerkandera adusta were analyzed by high-performance liquid chromatography with diode array detection and with liquid chromatography-electrospray ionization-tandem mass spectrometry. Sulfophthalimides (SPI; 3 and 4) were identified as major metabolites by comparison with synthesized reference compounds. SPI was formed from both dyes in fungal cultures and by incubation with its purified manganese peroxidase and lignin peroxidase. Quantitative assessment of the SPI formed from RB15 accounted for approximately 60% of the theoretical amount.

Sulfophthalimide as major metabolite formed from sulfonated phthalocyanine dyes by the white-rot fungus Bjerkandera adusta

The reaction products formed during the decolorization of the sulfophthalocyanine textile dyes Reactive blue 15 (RB15) and Reactive blue 38 (RB38) by the white-rot fungus Bjerkandera adusta were analyzed by high-performance liquid chromatography with diode array detection and with liquid chromatography–electrospray ionization–tandem mass spectrometry. Sulfophthalimides (SPI; 3 and 4) were identified as major metabolites by comparison with synthesized reference compounds. SPI was formed from both dyes in fungal cultures and by incubation with its purified manganese peroxidase and lignin peroxidase. Quantitative assessment of the SPI formed from RB15 accounted for approximately 60% of the theoretical amount.