High-level production and characterization of laccase from a newly isolated fungus Trametes sp. LS-10C

Leiotrametes flavida MTCC 12927 laccase: scaleup, purification and its application for dye decolourisation enhanced by water-soluble mediator TEMPOL

Laccase production from an isolated white rot fungus identified as Leiotrametes flavida MTCC 12927 was optimised in flasks, scaled up in 5 and 10 L working volume fermenters and purified to homogeneity. Purified laccase was tested for its decolourisation potential on 3 dyes: Basic Red 46 (azo class), Acid Blue 9 (triarylmethane class) and Reactive Blue 21 (phthalocyanine class). TEMPOL (4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl), a less expensive water-soluble hydroxy derivative of mediator TEMPO (2,2,6,6-tetramethylpiperidin-1-yl) oxidanyl), was tested as a mediator which had not been reported before to our knowledge along with well-known mediators hydroxybenzotriazole (HBT) and syringaldehyde (SYD). Laccase in the presence of HBT could decolourise all the 3 dyes. Basic Red 46 and Acid Blue 9 were completely decolourised in 4 and 8 h, respectively. Reactive Blue 21 showed a decolourisation of 70.3% compared to 50.3% with TEMPOL and 20% with the enzyme alone. Laccase + TEMPOL combination was significantly better than HBT in decolourising azo dye Basic Red 46 completely within 30 min compared to 4 h for HBT. Furthermore, laccase TEMPOL and HBT combinations were also tested in azo dye-containing tannery effluent. TEMPOL showed a higher decolourisation rate of 36% compared to 22% for the latter. Chemical oxygen demand (COD) analysis of treated effluent samples showed a COD reduction of 23.2% for laccase + TEMPOL treatment and 19.2% for laccase + HBT compared to 7.8% with laccase alone. TEMPOL showed potential as a low-cost, water-soluble mediator for azo dye decolourisation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-025-04259-9.

Photothermal degradation of triphenylmethane dye wastewater by Fe3O4@C-laccase

The degradation of synthetic dye wastewater is important for green chemistry and cost-effectiveness. In this study, we developed Fe3O4@C-laccase (laccase immobilized on Fe3O4@C nanoparticles) for photothermal degradation of high concentration of triphenylmethane dye wastewater. The Fe3O4@C-laccase possessed superior pH and thermal stabilities, as well as excellent tolerance to organic solvents, inhibitors, and metal ions. Laccase activity assays revealed that the activity recovery was approximately 118.2 %. Furthermore, the Fe3O4@C-laccase presented rapid and sustainable photothermal degradation capabilities to triphenylmethane dye wastewater. The initial removal efficiencies of 400 mg/L malachite green (MG), 400 mg/L brilliant green (BG), 100 mg/L crystal violet (CV), and 600 mg/L mixed dye (MG:BG:CV = 1:1:1) wastewater were approximately 99.8 %, 99.9 %, 96.4 % and 99.2 % by 60 min treatment, respectively. After undergoing 10 batches of reuse, the photothermal degradation efficiencies of the triphenylmethane dye wastewater remained consistently high, at about 99.3 %, 97.4 %, 94.0 %, and 95.1 %, respectively. The excellent photothermal degradation properties indicate that the Fe3O4@C-laccase holds promise for addressing high concentration of textile wastewater in various applications.

Activity of Lignin-Modifying Enzyme of Selected Medicinal Mushrooms in Submerged Fermentation of Lignocellulosic Materials

In the present study, wide diversity in the set and activity of lignin-modifying enzymes (LME) was revealed during submerged fermentation of mandarin peel with 15 strains of white rot Basidiomycetes. Among them, Trametes pubescens BCC153 was distinguished by the simultaneous production of laccase, manganese peroxidase (MnP), and lignin peroxidase (LiP). Supplementation of CuSO4 at a concentration of 1 mM in the media for the cultivation of four Trametes species manifold increased the production of laccase. The diverse effects of chemically different lignocellulosic growth substrates and nitrogen sources on the production of individual LME have been established. The maximum laccase activity of T. pubescens was observed when the fungus was cultivated on media containing mandarin peel and wheat bran, whereas the highest MnP and LiP activities were detected in the submerged fermentation of tobacco residue. Peptone and casein hydrolysate appeared to be the best sources of nitrogen to produce laccase and both peroxidases by T. pubescens BCC153 whereas KNO3 was the worst nitrogen-containing compound for the production of all enzymes.

Agitation role (Dissolved Oxygen) in production of laccase from newly identified Ganoderma multistipitatum sp. nov. and its effect on mycelium morphology

BACKGROUND

Agitation speed influenced the production rate of laccase. Orbital speed not only influenced the enzyme production, but was also effective to dissolve the oxygen during growth of mycelium, spores, and chlamydospores. Shear effects of speed greatly influenced the morphology of mycelium.

METHODS

Ganoderma multistipitatum was identified by ITS marker. Phylogenetic tree was constructed for species identification. Qualitatively by plate method contained guaiacol indicator, while quantitatively by submerged fermentation and Central Composite Design applied on agitation parameter for maximum laccase potential of this species. The effects of agitation speed on mycelium morphology were observed under compound and scanning electron microscope.

RESULTS

Statistical optimization of agitation conditions were performed by using response surface methodology to enhance the production of laccase from Ganoderma multistipitatum sp. nov. Maximum laccase yield (19.44 × 105 ± 0.28 U/L) was obtained at 150 rpm grown culture, which was higher than predicted value of laccase production (19.18 × 105 U/L) under aerobic conditions (150 rpm). The 150 rpm provided the continuous flush of oxygen. The DO (dissolved oxygen) was maximum (65%) for "27 h" incubation at 150 rpm during laccase synthesis. The statistical value of laccase production was minimum under anaerobic or nearly static condition of 50 rpm. The predicted (12.78 × 105 U/L) and obtained (12.82 × 105 U/L) yield was low at 50 rpm. Optimization of orbital shaking for aeration conditions were performed by the use of "Response Surface Methodology". The submerged shaking flasks were utilized as a nutrients growth medium to maximize the production of laccase from G. multistipitatum. The minimum incubation time highly influenced the laccase yield from 7 to 15 days via utilization of less cost-effective medium under a promising and eco-friendly method. The morphological effects of rpm on mycelium were examined under compound and scanning electron microscopy. Higher rpm (200, 230) shear the mycelium, while 150 to 200 rpm exhibited smoother and highly dense branches of mycelia.

CONCLUSION

The shear forces of 200 rpm caused the damages of mycelium and cells autolysis with less laccase production. This study concluded that 150 rpm saved the life of mycelium and enhanced the production rate of enzymes.

Production of a novel laccase from Ceratorhiza hydrophila and assessing its potential in natural dye fixation and cytotoxicity against tumor cells

BACKGROUND

Flavonoid natural dyes have gained attention because they are nontoxic and eco-friendly. However, they do not work effectively with artificial fibers and require the use of mordants, which are considered as hazardous chemicals. Laccase enzyme catalyzes the oxidation of phenols, forming phenoxyl radicals that undergo a further polymerization process. So, laccase can oxidize flavonoid dyes, and it can be used instead of harmful mordants in flavonoid dye fixation on cotton fabrics. Laccases also are involved in a variety of metabolic processes, and they have anti-proliferative effects toward HepG2 and MCF-7 tumor cells.

RESULTS

Among fifteen fungal isolates, the fungus Ceratorhiza hydrophila isolated from the submerged plant Myriophyllum spicatum was selected as the most potent laccase producer. Optimization of the production medium resulted in a 9.9-fold increase in laccase productivity. The partially purified Ceratorhiza hydrophila laccase could successfully improve the affinity of cotton fabrics toward quercetin (flavonoid) dye with excellent color fastness properties. The partially purified laccase also showed anti-proliferative activity against HepG2 and MCF-7 tumor cells. However, high laccase concentration is required to estimate IC50.

CONCLUSIONS

Ceratorhiza hydrophila MK387081 is an excellent laccase producer. The partially purified laccase from Ceratorhiza hydrophila can be used in textile dyeing and printing processes as a safer alternative to the conventional hazardous mordants. Also, it can be used in preparation of cancer treatment drugs. However, further studies are needed to investigate IC50 for both cell types at higher laccase concentrations.

Enhanced laccase production by mutagenized Myrothecium verrucaria using corn stover as a carbon source and its potential in the degradation of 2-chlorophen

Chlorophenols are widely used in industry and are known environmental pollutants. The degradation of chlorophenols is important for environmental remediation. In this study, we evaluated the biodegradation of 2-chlorophenol using crude laccase produced by Myrothecium verrucaria. Atmospheric and room temperature plasma technology was used to increase laccase production. The culture conditions of the M-6 mutant were optimized. Our results showed that corn stover could replace glucose as a carbon source and promote laccase production. The maximum laccase activity of 30.08 U/mL was achieved after optimization, which was a 19.04-fold increase. The biodegradation rate of 2-chlorophenol using crude laccase was 97.13%, a positive correlation was determined between laccase activity and degradation rate. The toxicity of 2-CP was substantially reduced after degradation by laccase solution. Our findings show the feasibility of the use of corn stover in laccase production by M. verrucaria mutant and the subsequent biodegradation of 2-chlorophenol using crude laccase.

Optimization, purification and characterization of laccase from Ganoderma leucocontextum along with its phylogenetic relationship

The aim of this work to study an efficient laccase producing fungus Ganoderma leucocontextum, which was identified by ITS regions of DNA and phylogenetic tree was constructed. This study showed the laccase first-time from G. leucocontextum by using medium containing guaiacol. The growth cultural (pH, temperature, incubation days, rpm) and nutritional (carbon and nitrogen sources) conditions were optimized, which enhanced the enzyme production up to 4.5-folds. Laccase production increased 855 U/L at 40 °C. The pH 5.0 was suitable for laccase secretion (2517 U/L) on the 7th day of incubation at 100 rpm (698.3 U/L). Glucose and sucrose were good carbon source to enhance the laccase synthesis. The 10 g/L beef (4671 U/L) and yeast extract (5776 U/L) were the best nitrogen source for laccase secretion from G. leucocontextum. The laccase was purified from the 80% ammonium sulphate precipitations of protein identified by nucleotides sequence. The molecular weight (65.0 kDa) of purified laccase was identified through SDS and native PAGE entitled as Glacc110. The Glacc110 was characterized under different parameters. It retained > 90% of its activity for 16 min incubation at 60 °C in acidic medium (pH 4.0). This enzyme exerted its optimal activity at pH 3.0 and temperature 70 °C with guaiacol substrate. The catalytic parameters K_m and V_max was 1.658 (mM) and 2.452 (mM/min), respectively. The thermo stability of the laccase produced by submerged fermentation of G. leucocontextum has potential for industrial and biotechnology applications. The results remarked the G. leucocontextum is a good source for laccase production.

Improved performance of immobilized laccase for catalytic degradation of synthetic dyes using redox mediators

Laccase is an important biodegradation agent as the catalytic degradation could be enhanced in the presence of redox mediators. This work aims to improve removal performance of the immobilized laccase...

Enhancement of laccase production from a newly isolated Trichoderma harzianum S7113 using submerged fermentation: Optimization of production medium via central composite design and its application for hydroquinone degradation

Trichoderma harzianum S7113 as an efficient fungal isolate for laccase production was identified using the 18S rRNA sequencing. T. harzianum S7113 attained its maximal laccase production level on the 14^th day of static incubation at 28 °C and pH 5.0 using the inoculum size of 5 discs (14 mm), according to the one factor per time (OFT) method. The most appropriate carbon, organic and inorganic nitrogen sources to promote maximal laccase synthesis were glucose (15 g/L), beef extract (5 g/L), and ammonium chloride (4 g/L), respectively. Results of Response Surface Methodology (RSM) revealed that glucose, meat extract, and ammonium chloride concentrations of 17.54, 7.17, and 4.36 g/L respectively, at a pH value of 6.74 are the favorite conditions for high titer production. The ANOVA analysis highlighted an excellent match between the actual experimental results and the model predicted laccase production levels. The biodegradation of hydroquinone (HQ) by T. harzianum S7113 laccase was most efficient in the pH range of 5.0 to 6.5. The increase in laccase concentration led to a significant increase in the HQ conversion to get a biodegradation rate of 92 ± 2.6% with a laccase concentration of 0.75 U/mL after 3 h of reaction.

A Brief History of Colour, the Environmental Impact of Synthetic Dyes and Removal by Using Laccases

The history of colour is fascinating from a social and artistic viewpoint because it shows the way; use; and importance acquired. The use of colours date back to the Stone Age (the first news of cave paintings); colour has contributed to the social and symbolic development of civilizations. Colour has been associated with hierarchy; power and leadership in some of them. The advent of synthetic dyes has revolutionized the colour industry; and due to their low cost; their use has spread to different industrial sectors. Although the percentage of coloured wastewater discharged by the textile; food; pharmaceutical; cosmetic; and paper industries; among other productive areas; are unknown; the toxic effect and ecological implications of this discharged into water bodies are harmful. This review briefly shows the social and artistic history surrounding the discovery and use of natural and synthetic dyes. We summarise the environmental impact caused by the discharge of untreated or poorly treated coloured wastewater to water bodies; which has led to physical; chemical and biological treatments to reduce the colour units so as important physicochemical parameters. We also focus on laccase utility (EC 1.10.3.2), for discolouration enzymatic treatment of coloured wastewater, before its discharge into water bodies. Laccases (p-diphenol: oxidoreductase dioxide) are multicopper oxidoreductase enzymes widely distributed in plants, insects, bacteria, and fungi. Fungal laccases have employed for wastewater colour removal due to their high redox potential. This review includes an analysis of the stability of laccases, the factors that influence production at high scales to achieve discolouration of high volumes of contaminated wastewater, the biotechnological impact of laccases, and the degradation routes that some dyes may follow when using the laccase for colour removal.

Substrate specificity of a new laccase from Trametes polyzona WRF03

Various aromatic compounds that are structurally analogous to lignin were tested as possible/preferred substrates for purified laccase from newly isolated white rote fungi, Trametes polyzona WRF03. The pH optima were tested using different substrates and kinetic studies were conducted at these pH optima. The pH optima in the presence of ABTS, α-naphthol, o-dianisidine, and catechol were 4.5 but 5.0 and 5.5 in the presence of guaiacol and pyrogallol, respectively. The initial velocities obtained from the kinetic study were analyzed using Graph Pad Prism 7 and Lineweaver-Burk plot to obtain kinetic constants (k_m and _Vmax) which were used to calculate substrate specificity. Amongst all the substrates tested, ABTS had the highest specificity-constant (181.51 M⁻¹s⁻¹), and therefore, the most preferred substrate was followed by α-naphthol, o-dianisidine, guaiacol, pyrogallol, and catechol. Resorcinol, orcinol, and veratryl alcohol did not display any considerable chemical shift in the presence of Trametes polyzona WRF03 laccase. Also, oxidation of phenolic substrates appeared to be dependent on the nature of the substituent groups and their relative position on the aromatic nucleus. Since most of these substrates are structural analogs of lignin and many recalcitrant environmental pollutants, the enzyme may find application in delignification, treatment of wastewater containing dyes, and polycyclic aromatic hydrocarbons (PAHs).

Purification and characterisation of new laccase from Trametes polyzona WRF03

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Trametes polyzona WRF03 produced high yield of true laccase.

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Trametes polyzona WRF03 laccase was relatively pH and temperature stable.

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Fe²⁺, sodium azide and sodium cyanide greatly inhibited laccase activity.

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Trametes polyzona WRF03 laccase decolorised many classes of synthetic dyes.

The molecular screening for laccase specific gene sequences in Trametes polyzona WRF03 (TpWRF03) using designed oligonucleotide primers analogous to the conserved sequences on the copper-binding regions of known laccases showed positive amplification with an amplicon size corresponding to 1500 bp. The purified TpWRF03 laccase (TpL) is a monomer with a molecular weight corresponding to 66 kDa. The enzyme had an optimal pH of 4.5 and temperature of 55 °C. TpL was most stable within pH of 5.5–6.5 and at a temperature range of 40–50 °C. Sodium azide, sodium cyanide and Fe²⁺ greatly inhibited the enzyme activity. TpL showed more than 50 % decolourisation efficiency on coomassie brilliant blue (72.35 %) and malachite green (57.84 %) but displayed low decolourisation efficiency towards Azure B (1.78 %) and methylene blue (0.38 %). The results showed that TpWRF03 produces high-yield of true laccase with robust properties for biotechnological applications.

Laccase isoform diversity on basal medium in Cyathus bulleri and role in decolorization/detoxification of textile dyes and effluent

Laccases (EC 1.10.3.2) are multi-copper oxidases that can degrade several xenobiotics, including textile dyes. Present study investigated the nature of laccase isoforms induced by 2,6-dimethylaniline in Cyathus bulleri cultivated on basal salt medium. Two isoforms, LacI and LacII were identified and purified by a combination of ultrafiltration and ion-exchange chromatography. The MS spectrum of the two proteins displayed a number of non-identical and identical molecular peaks (m/z), and, the latter were mapped to protein originating from the previously reported Laccase (Lcc) 1 gene. The LacI isoform exhibited higher catalytic efficiency (K_cat/K_m) towards 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), 2,6-dimethoxyphenol, guaiacol and pyrogallol and was tolerant to high levels of chloride ions and resistant to EDTA. Higher decolorization of several dyes such as Direct Scarlet B (67%), Reactive Brilliant blue-R (96%), Direct Orange 34 (50%) and Reactive Red198 (95%) by the LacI isoform makes it a good candidate for degradation of synthetic dyes. The decolorization of Direct Orange 34 by laccases is being reported for the first time. Many of the properties exhibited by this isoform make it a good candidate for large scale production and applications for use in the dyeing industry.

Sequential combination of laccase pretreatment and acid extraction for high-yield pectin production from pomelo peels

A sequential combination of laccase pretreatment and acid extraction of pectin from pomelo peels was performed in this study. By using a laccase dose of 10 U/g, the yield and galacturonic acid content of the extracted pectin were 21.67% and 75.74%, respectively, which reflected an improvement by nearly 30% and 44% relative to the extraction process without laccase. Moreover, the degree of esterification of the extracted pectin was significantly improved as the laccase concentration was increased from 0 to 10 U/g but did not affect the molecular weight. Besides, the enzyme-treated sample displayed more than 29% loss of total lignin, in which the acid soluble lignin and the acid insoluble lignin were removed by over 15% and 33%, respectively. Scanning electron microscopy indicated that the penetration and partial destruction of the pomelo peel cell wall due to laccase might be one of the main reasons why laccase pretreatment could release pectin from cell wall complexes and increase the pectin yield in subsequent acid extraction processes.

A Sight to Wheat Bran: High Value-Added Products

Recently more consideration has been given to the use of renewable materials and agricultural residues. Wheat production is increasing yearly and correspondingly, the volume of by-products from the wheat process is increasing, as well. It is important to find the use of the residuals for higher value-added products, and not just for the food industry or animal feed purposes as it is happening now. Agricultural residue of the roller milled wheat grain is a wheat bran description. The low-cost of wheat bran and its composition assortment provides a good source of substrate for various enzymes and organic acids production and other biotechnological applications. The main purpose of this review article is to look into recent trends, developments, and applications of wheat bran.

Purification and characterization of a fungal laccase from the ascomycete Thielavia sp. and its role in the decolorization of a recalcitrant dye

A laccase-producing ascomycete was isolated from arid soil in Tunisia. This fungus was identified as Thielavia sp. using the phylogenetic analysis of rDNA internal transcribed spacers. The extracellular laccase produced by the fungus was purified to electrophoretic homogeneity, showing a molecular mass around 70 kDa. The enzyme had an optimum pH of 5.0 and 6.0 for ABTS and 2,6‑DMP, respectively and it showed remarkable high thermal stability, showing its optimal temperature at 70 °C (against 2,6‑DMP). It presented slight inhibiting effect by EDTA, SDS and l‑cyst although this effect was more marked by sodium azide (0.1 mM). On the other hand, it showed tolerance to up to 300 mM NaCl, retaining around 50% of its activity at 900 mM. Among the metal ions tested on TaLac1, Mn²⁺ showed an activating effect. Their kinetic parameters K_m and k_cat were 23.7 μM and 4.14 s^-1 for ABTS, and 24.3 μM and 3.46 s^-1 towards 2,6‑DMP. The purified enzyme displayed greater efficiency in Remazol Brilliant Blue R decolorization (90%) in absence of redox mediator, an important property for biotechnological applications.

Production of Laccase by a New Myrothecium verrucaria MD-R-16 Isolated from Pigeon Pea [Cajanus cajan (L.) Millsp.] and its Application on Dye Decolorization

The present study was conducted to screen a laccase-producing fungal endophyte, optimize fermentation conditions, and evaluate the decolorization ability of the laccase. A new fungal endophyte capable of laccase-producing was firstly isolated from pigeon pea and identified as Myrothecium verrucaria based on a ITS-rRNA sequences analysis. Meanwhile, various fermentation parameters on the laccase production were optimized via response surface methodology (RSM). The optimal fermentation conditions were a fermentation time of five days, temperature 30 °C and pH 6.22. Laccase activity reached 16.52 ± 0.18 U/mL under the above conditions. Furthermore, the laccase showed effective decolorization capability toward synthetic dyes (Congo red, Methyl orange, Methyl red, and Crystal violet) in the presence of the redox mediator ABTS, with more than 70% of dyes decolorizing after 24 h of incubation. Additionally, the activity of laccase was relatively stable with pH (4.5-6.5) and a temperature range of 35-55 °C. Therefore, the high laccase production of the strain and the new fungal laccase could provide a promising alterative approach for industrial and environmental applications.