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•The prospects of T. versicolor in lignocellulose-based bioeconomy are encouraging.•Solid-state fermentation – a promising technology for lignocellulosic biorefineries.•T. versicolor ...and laccase crude extracts are both efficient in wastewater treatment.•Great potential for lignocellulose valorization to feed, biogas and biofertilizers.
Although Trametes versicolor is one of the most investigated white-rot fungi, the industrial application of this fungus and its metabolites is still far from reaching its full potential. This review aims to highlight the opportunities and challenges for the industrial use of T. versicolor according to the principles of circular bioeconomy. The use of this fungus can contribute significantly to the success of efforts to valorize lignocellulosic waste biomass and industrial lignocellulosic byproducts. Various techniques of T. versicolor cultivation for enzyme production, food and feed production, wastewater treatment, and biofuel production are listed and critically evaluated, highlighting bottlenecks and future perspectives. Applications of T. versicolor crude laccase extracts in wastewater treatment, removal of lignin from lignocellulose, and in various biotransformations are analyzed separately.
•Basis for utilization of konjac flying powder on wood protectors were provided.•The antifungal active fractions are mainly organic acids and plant essential oils.•Konjac flying powder might provide ...a natural alternative for wood preservatives.•Plant containing essential oils and organic acids might have antifungal potential.
Public concern for the environment has stimulated the development of natural wood preservatives. The antifungal activity of konjac (Amorphophallus konjac K. Koch) flying powder (a by-product produced during mechanical processing of konjac flour) ethanol extracts was evaluated against wood decay fungi in poplar (Populus nigra L.). Compounds associated with antifungal activity in the extracts were isolated and purified by silica gel column chromatography. The antifungal active fractions were identified by ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS). The ethanol extracts showed better activity against the brown-rot fungus, Gloeophyllum trabeum (Pers.: Fr.) Murr. than the white-rot fungus, Trametes versicolor (L. ex Fr.) Quél. in poplar. The antifungal active fractions were mainly composed of organic acids and plant essential oils. Salicylic acid, 2,4,6-trichlorophenol, vanillin and cinnamaldehyde were present in the active fractions. These compounds showed high efficacy against both fungi in poplar. The results indicate that konjac extracts have potential as natural wood protectants and suggested that some fractions of konjak flying powder may be useful for protecting wood against fungal attack.
Teakwood from fast-growth plantations is commercialized at increasingly younger ages for economic reasons. However, wood features are influenced by the age of the tree. This study examined how age ...affects heartwood proportion, color parameters, chemical composition, and natural teakwood durability. Trees with 5, 10, 15, and 20 years of fast-growth at commercial plantations located in Mato Grosso, Brazil were evaluated. The base diameter of the trees ranged from 13.1 (5 years) to 28.3 cm (20 years), and the heartwood percentage increased from 16.3 to 60.0%, respectively. The color parameters in the CIELab system indicated that wood became darker and more saturated, and the predominance of yellow color decreased compared with red as age advanced. The total extractive content ranged between 7.4 (5 years) and 9.6% (15 years), without a clear trend of age affecting the extractive content. The extractives from five-year-old wood were mainly composed of tectoquinone (43.3%), phthalic acid (19.1%), and 1,3-indandione (9.2%), while those from 20-year-old wood were mainly composed of tectoquinone (60.7%), lapachol (13.8%), and phthalic acid (9.7%). Teakwood can be classified as resistant (5 years) to very resistant (20 years) after being submitted to an accelerated decay test.
The potential application of fungal laccase-assisted bioremediation for estrogen elimination has caused tremendous attention. Herein, naturally-occurring Trametes versicolor laccase (Tvlac) was ...capable of significantly removing 17β-estradiol (E2) and 17α-ethynylestradiol (EE2) at pH 5. A lower (or higher) pH caused decline in the velocity constants (kprcs) by obstructing the single-electron oxidation of estrogen at Tvlac T1-Cu site (or intercepting the intramolecular-electron transfer between Tvlac T1-Cu and T2/T3-Cu sites). Humic acid (HA) and natural phenolic compounds (PCs) are omnipresent in water and can influence the conversion kinetics of estrogen in Tvlac-triggered reactions. Compared with HA-free, the kprcs values of E2 and EE2 in presence of HA respectively reduced 58.61%–83.72% and 69.72%–95.62% at different pH levels. Additionally, the kprcs values for estrogen were also hampered obviously by O-dihydroxyphenol structure of model PCs, owning to the created monomeric/polymeric O-quinones inverted estrogen phenoxy radicals. The generated carbon‑carbon/oxygen self-linking aggregates during Tvlac-mediated estrogen oxidative coupling were characterized, and the polymerization mechanisms were speculated. A fluid-bed reactor with cross-linked-entrapped Tvlac in Ca-alginate beads was established to treat E2 and EE2, respectively. Compared with free Tvlac, immobilized Tvlac prominently exhibited a higher pH and temperature stability. Especially, the fluid-bed reactor with immobilized Tvlac could be reused, keeping its high conversion efficiencies of E2 and EE2 in natural water, only changing from 99.2% to 73.6% and from 98.5% to 70.9% after 1 to 5 cycles, respectively. These findings present an alternative immobilized fungal laccase-based clean biotechnology for continuously handling estrogen-contaminated waterbodies at a large-scale.
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•Tvlac-assisted conversion kinetics of estrogen exhibited strong pH dependency.•HA evidently blocked removal of estrogen through quenching estrogen radicals.•Tvlac aided self/cross-linking of estrogen and PCs to create new polymeric species.•A fluid-bed reactor with cross-linked-entrapped Tvlac within Ca-AB was designed.•Immobilized Tvlac owned great reuse potential to continuously eliminate estrogen.
•Isoproturon can be completely degraded by laccase-mediator systems.•Synthetic mediators are more effective for the isoproturon degradation.•Mediators can affect laccase stability in the degradation ...of isoproturon.•PEG can reduce the HBT dosage and enhance the degradation rate of isoproturon.•A higher degradation rate of isoproturon was observed in real wastewater.
This study investigated the degradation of the herbicide isoproturon using Trametes versicolor laccase and its laccase-mediator systems. Isoproturon was poorly degraded with laccase alone, due to the presence of the relatively strong withdrawing electron group (NHCON(CH3)2) in the chemical structure of isoproturon. This study showed that laccase-mediator systems can effectively enhance the degradation rate of isoproturon. Within 24h, isoproturon was completely degraded in the presence of 0.3U/mL laccase and 1mM 1-hydroxybenzotriazole (HBT). Compared with natural mediators, synthetic mediators are more effective in the laccase-mediated degradation of isoproturon. However, laccase activity rapidly declined in the presence of the synthetic mediator HBT. Degradation occurred at an acidic pH and optimum temperature was 50°C. A high concentration (10mM) of metal ions Cu2+, Zn2+ and Cd2+ positively enhanced isoproturon degradation with the laccase-HBT system. Polyethylene glycol (PEG) can reduce the HBT dosage in isoproturon degradation with the laccase-HBT system and enhance the degradation rate of isoproturon by increasing laccase stability. Moreover, a higher degradation rate of isoproturon was observed when incubating isoproturon with the laccase-HBT system in real wastewater compared to that in sodium citrate buffer. Finally, transformation products showed much lower ecotoxicity to green algae than the original isoproturon. This study concludes that laccase-mediator systems have great potential to treat industrial wastewater containing the herbicide isoproturon.
Trametes versicolor is a promising white-rot fungus for the biological pretreatment of lignocellulosic biomass. In the present work, T. versicolor ATCC 20869 was grown on Pinus taeda wood chips under ...solid-state fermentation conditions to examine the wood-degrading mechanisms employed by this fungus. Samples that were subjected to fungal pretreatment for one-, two- and four-week periods were investigated. The average mass loss ranged from 5 % to 8 % (m m super(-) super(1)). The polysaccharides were preferentially degraded: hemicellulose and glucan losses reached 13.4 % and 6.9 % (m m super(-) super(1)) after four weeks of cultivation, respectively. Crude enzyme extracts were obtained and assayed using specific substrates and their enzymatic activities were measured. Xylanases were the predominant enzymes, while cellobiohydrolase activities were marginally detected. Endoglucanase activity, beta -glucosidase activity, and wood glucan losses increased up to the second week of biodegradation and remained constant after that time. Although no lignin-degrading enzyme activity was detected, the lignin loss reached 7.5 % (m m super(-) super(1)). Soluble oxalic acid was detected in trace quantities. After the first week of biodegradation, the Fe super(3+)-reducing activity steadily increased with time, but the activity levels were always lower than those observed in the undecayed wood. The progressive wood polymer degradation appeared related to the secretion of hydrolytic enzymes, as well as to Fe super(3+)-reducing activity, which was restored in the cultures after the first week of biodegradation.
Genes in prokaryotic genomes are often arranged into clusters and co-transcribed into polycistronic RNAs. Isolated examples of polycistronic RNAs were also reported in some higher eukaryotes but ...their presence was generally considered rare. Here we developed a long-read sequencing strategy to identify polycistronic transcripts in several mushroom forming fungal species including Plicaturopsis crispa, Phanerochaete chrysosporium, Trametes versicolor, and Gloeophyllum trabeum. We found genome-wide prevalence of polycistronic transcription in these Agaricomycetes, involving up to 8% of the transcribed genes. Unlike polycistronic mRNAs in prokaryotes, these co-transcribed genes are also independently transcribed. We show that polycistronic transcription may interfere with expression of the downstream tandem gene. Further comparative genomic analysis indicates that polycistronic transcription is conserved among a wide range of mushroom forming fungi. In summary, our study revealed, for the first time, the genome prevalence of polycistronic transcription in a phylogenetic range of higher fungi. Furthermore, we systematically show that our long-read sequencing approach and combined bioinformatics pipeline is a generic powerful tool for precise characterization of complex transcriptomes that enables identification of mRNA isoforms not recovered via short-read assembly.
Microbial remediation of organically combined contaminated sites is currently facing technical challenges. White rot fungi possess broad-spectrum degradation capabilities, but most of the studies are ...conducted on polluted water bodies, and few research focus on the degradation of combined organically contaminated soils. This study aimed to investigate the physiological changes in
to enhance its simultaneous degradation ability towards benzo(a)pyrene (BaP) and TPH. The results demonstrated that
, when subjected to liquid fermentation, achieved an 88.08% degradation of individual BaP within 7 days. However, under the combined contamination conditions of BaP and TPH, the BaP degradation rate decreased to 69.25%, while the TPH degradation rate was only 16.95%. Furthermore, the degradation rate of BaP exhibited a significant correlation with the extracellular protein concentration and laccase activities. Conversely, the TPH degradation rate exhibited a significant and positive correlation with the intracellular protein concentration. Solid-state fermentation utilizing fungal agents proved to be the most effective method for removing BaP and TPH, yielding degradation rates of 56.16% and 15.73% respectively within 60 days. Overall,
demonstrated a commendable capability for degrading combined PAHs-TPH pollutants, thereby providing theoretical insights and technical support for the remediation of organically combined contaminated sites.
Fungal bioremediation emerges as an effective technology for pesticide treatment, but its successful implementation depends on overcoming the problem of microbial contamination. In this regard, ...fungal immobilization on wood seems to be a promising strategy, but there are two main drawbacks: the predominant removal of pesticides by sorption and fungal detachment. In this study, agricultural wastewater with pesticides was treated by Trametes versicolor immobilized on wood chips in a rotary drum bioreactor (RDB) for 225 days, achieving fungal consolidation and high pesticide biodegradation through two main improvements: the use of a more favorable substrate and the modification of operating conditions. Fungal community dynamic was assessed by denaturing gradient gel electrophoresis (DGGE) analysis and subsequent prominent band sequencing, showing a quite stable community in the RDB, mainly attributed to the presence of T. versicolor. Pesticide removals were up to 54 % diuron and 48 % bentazon throughout the treatment. Afterwards, pesticide-contaminated wood chips were treated by T. versicolor in a solid biopile-like system. Hence, these results demonstrate that the microbial contamination constraint has definitely been overcome, and fungal bioremediation technology is ready to be implemented on a larger scale.
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•A fungal bioremediation treatment was successfully operated for more than 7 months.•Using the suitable substrate and operating conditions improved biomass retention.•Inoculation of T. versicolor led to the establishment of a stable fungal consortium.•Fungal bioremediation technology is ready for full-scale application.
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