Laccase Research Papers - Academia.edu (original) (raw)

Laccases have received much attention from researchers in last decades due to their ability to oxidise both phenolic and non-phenolic lignin related compounds as well as highly recalcitrant environmental pollutants, which makes them very... more

Laccases have received much attention from researchers in last decades due to their ability to oxidise both phenolic and non-phenolic lignin related compounds as well as highly recalcitrant environmental pollutants, which makes them very useful for their application to several biotechnological processes. Such applications include the detoxification of industrial effluents, mostly from the paper and pulp, textile and petrochemical industries, use as a tool for medical diagnostics and as a bioremediation agent to clean up herbicides, pesticides and certain explosives in soil. Laccases are also used as cleaning agents for certain water purification systems, as catalysts for the manufacture of anti-cancer drugs and even as ingredients in cosmetics. In addition, their capacity to remove xenobiotic substances and produce polymeric products makes them a useful tool for bioremediation purposes. This paper reviews the applications of laccases within different industrial fields as well as their potential extension to the nanobiotechnology area.

... Truffle tyrosinase: Properties and activity Michele Miranda', Antonella Bonfiglia, Osvaldo Zarivia, Anna Maria Ragnellia, Giovanni Pacionib and ... BC Malmstrom, LE Andreasson and B. Reinhammar, Copper-containing oxidases... more

... Truffle tyrosinase: Properties and activity Michele Miranda', Antonella Bonfiglia, Osvaldo Zarivia, Anna Maria Ragnellia, Giovanni Pacionib and ... BC Malmstrom, LE Andreasson and B. Reinhammar, Copper-containing oxidases and superoxide dismutase, in: PD Boyer (Ed.), The ...

Phanerochaete chrysosporium, Pleurotus ostreatus, Trametes versicolor and Bjerkandera sp. BOL13 were tested for their ability to degrade the endocrine-disrupting compound nonylphenol at an initial concentration of 100 mg l−1. The highest... more

Phanerochaete chrysosporium, Pleurotus ostreatus, Trametes versicolor and Bjerkandera sp. BOL13 were tested for their ability to degrade the endocrine-disrupting compound nonylphenol at an initial concentration of 100 mg l−1. The highest removals were achieved with T. versicolor and Bjerkandera sp. BOL13, which were able to degrade 97 mg l−1 and 99 mg l−1 of nonylphenol in 25 days of incubation, respectively. Nonylphenol removal was associated with the production of laccase by T. versicolor, but the levels of laccase, manganese peroxidase and lignin peroxidase produced by Bjerkandera sp. BOL13 were very low. At 14°C, T. versicolor and Bjerkandera sp. BOL13 sustained the removal of 88 mg l−1 and 79 mg l−1 of nonylphenol, respectively. No pollutant removal was recorded at 4°C, although both fungi could grow at this temperature in the absence of nonylphenol. A microtoxicity assay showed that the fungi produced compounds that were toxic to Vibrio fischerii; and thus a reduction in toxicity could not be correlated with nonylphenol metabolism. T. versicolor and Bjerkandera sp. BOL13 were capable of colonizing soil artificially contaminated with 430 mg kg−1 of nonylphenol. Only 1.3±0.1% of nonylphenol remained in the soil after 5 weeks of incubation.

During recent years investigation on the development of eco-friendly processes for production of gold nanoparticles (GNPs) have received much attention due to hazardous effects of chemical compounds used for nanoparticle preparation. In... more

During recent years investigation on the development of eco-friendly processes for production of gold nanoparticles (GNPs) have received much attention due to hazardous effects of chemical compounds used for nanoparticle preparation. In the present study, the purified laccase from Paraconiothyrium variabile was applied for synthesis of Au nanoparticles (AuNPs) and the properties of produced nanoparticles were characterized. The UV–vis spectrum

The ability of peroxidases and laccases enzymes to treat organic pollutants is reviewed. Enzymatic methods generally have low energy requirements, are easy to control, can operate over a wide range of conditions and have a minimal... more

The ability of peroxidases and laccases enzymes to treat organic pollutants is reviewed. Enzymatic methods generally have low energy requirements, are easy to control, can operate over a wide range of conditions and have a minimal environmental impact. Peroxidases and laccases have broad substrate specificities and can catalyze the oxidation of a wide range of toxic organic compounds. The results show that an enzymatic oxidation can diminish the toxicity of some polycyclic aromatic hydrocarbons (PAHs), phenols, organophosphorus pesticides and azo dyes in laboratory and some field conditions. Due to the hydrophobicity and low aqueous solubility of these substrates, reactions are usually performed in the presence of organic solvents. However, it was detected that organic solvents can provoke enzyme denaturation, unfavorable substrate partition, inhibition or stabilization of enzyme–substrate complexes, depending on the enzyme, substrate and organic solvent used. Strategies to overcome these problems are proposed. Additionally, the low stability of heme-containing peroxidases to hydrogen peroxide, the low reaction rates of laccases, the mediators toxicity, the limited availability and high costs of these enzymes are other limitations detected for commercial applications. Due to field reaction conditions are more complex than laboratory conditions efforts have to be made to achieve the cheap overproduction of these biocatalysts in heterologous hosts and also their modification by chemical means or protein engineering to obtain more robust and active enzymes.

Laccase from the white rot fungus Coriolopsis polyzona was immobilized for the first time through the formation of cross-linked enzyme aggregates (CLEAs). Laccase CLEAs were produced by using 1000g of polyethylene glycol per liter of... more

Laccase from the white rot fungus Coriolopsis polyzona was immobilized for the first time through the formation of cross-linked enzyme aggregates (CLEAs). Laccase CLEAs were produced by using 1000g of polyethylene glycol per liter of enzyme solution as precipitant and 200muM of glutaraldehyde as a cross-linking agent. These CLEAs had a laccase activity of 148Ug(-1) and an activity recovery of 60.2% when using 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) as substrate. CLEAs formed by co-aggregation with bovine serum albumin (BSA) as a stabilizer showed lower laccase activity and affinity for ABTS than those without BSA. The CLEAs co-aggregated with BSA showed higher residual activity against a protease, NaN(3), EDTA, methanol and acetone. The thermoresistance was higher for CLEAs than for free laccase and also higher for CLEAs co-aggregated with BSA than for simple CLEAs when tested at a pH of 3 and a temperature of 40 degrees C. Finally, laccase CLEAs were teste...

Laccase production by the white-rot fungus Trametes versicolor (CBS100.29) grown in submerged cultures was studied. Addition of different insoluble lignocellulosic materials into the culture medium in order to enhance laccase production... more

Laccase production by the white-rot fungus Trametes versicolor (CBS100.29) grown in submerged cultures was studied. Addition of different insoluble lignocellulosic materials into the culture medium in order to enhance laccase production was investigated.The lignocellulosic materials were grape seeds, grape stalks and barley bran, selected because of their availability and low cost, since they are agro-industrial wastes abundant in most countries. Barley bran gave the highest activities, a maximum value of 639U/l, which was 10 times the value attained in the cultures without lignocellulosics addition.The decolourisation of a model dye, Phenol Red, by the ligninolytic fluids obtained in the above-mentioned cultures was investigated. Grape stalk and barley bran cultures showed the highest ability to decolourise the dye, attaining a percentage of decolourisation of around 60% in 72 h.

Laccase was reacted with gallic acid in the presence of a high-kappa (91) kraft pulp. The result was a modified pulp with 34%, 20%, and 72% improvements in burst, tensile, and wet tensile strength compared to untreated control samples.... more

Laccase was reacted with gallic acid in the presence of a high-kappa (91) kraft pulp. The result was a modified pulp with 34%, 20%, and 72% improvements in burst, tensile, and wet tensile strength compared to untreated control samples. Fully bleached pulps were not responsive to the laccase treatment, indicating lignin was the major target for the fiber modification. The results indicate that the strength increases were a combined effect of improvements of hydrogen bonding between fibers and creation of phenoxy radical cross-links within the sheet.

Filamentous fungi that produce mycotoxins also demonstrate the ability to degrade a wide variety of naturally occurring and anthropogenically generated hazardous wastes. Hence, these are emerging as excellent candidates for... more

Filamentous fungi that produce mycotoxins also
demonstrate the ability to degrade a wide variety of naturally
occurring and anthropogenically generated hazardous wastes.
Hence, these are emerging as excellent candidates for bioremediation.
Their mycelia exhibit the robustness of adapting to
highly restrictive environmental conditions often experienced
in the presence of persistent pollutants, which makes them
more useful compared to other microbes. However, it now
appears that several regulatory factors that govern mycotoxin
synthesis in these toxigenic strains also regulate their bioremediation
abilities. To this end, mycoremediation and mycotoxin
synthesis have been thoroughly but independently investigated;
hence, much less is understood about the overlaps
between the two processes. This review aims to shed light on
this critical knowledge gap and provide some useful insights
into the future research that might overcome the challenges
associated with these shared regulatory modules. This will
enable the harnessing of the full potential of mycoremediation
by minimizing mycotoxin contamination.