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Combining laccase with Cu(salen) catalysts for oxidation of kraft lignin

100%

Zhou X.-F., Tang K.

Drewno. Prace Naukowe. Doniesienia. Komunikaty

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2016

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tom 59

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nr 198

2

Purification and characterization of a novel laccase from the mushroom Pleurotus nebrodensis

86%

Tian G.-T., Zhang G.-Q., Wang H.-X., Ng T. B.

Acta Biochimica Polonica

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2012

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tom 59

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nr 3

A novel laccase with a molecular mass of 64 kDa and the N-terminal sequence AIGPDDTINF was isolated from fresh fruiting bodies of the mushroom Pleurotus nebrodensis. The purification protocol comprised ion exchange chromatography on DEAE-cellulose, CM-cellulose, and Q-Sepharose, and gel filtration on Superdex 75. The laccase was adsorbed on DEAE-cellulose and Q-Sepharose, but not on CM-cellulose. It demonstrated an optimal temperature of 70°C. The enzyme activity increased steadily over the temperature range 20°C-70°C. There was only a slight reduction in activity at 80°C. However, all activity disappeared following exposure to 100°C for 10 minutes. The enzyme activity changed only slightly over the pH range 3-5, with the optimum at pH 5, but underwent a precipitous decline when the pH was elevated to 6, and was undetectable at pH 8 and pH 9.

3

Effects of culture conditions on production of extracellular laccase by Rhizoctonia praticola

86%

Janusz G., Rogalski J., Barwinska M., Szczodrak J.

Polish Journal of Microbiology

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2006

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tom 55

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nr 4

It was found that the soil-dwelling fungus Rhizoctonia praticola 93A was capable to produce laccase in submerged cultures. Effects of culture conditions on the enzyme biosynthesis in shaken flask and aerated bioreactor cultures were evaluated to improve the yields of the process. Production of extracellular laccase was considerably intensified by the addition of Cu²⁺ to a carbon-limited and nitrogen-sufficient culture medium (C/N = 0.98). When an optimized medium containing glucose (2 g/l) and L-asparagine (1.5 g/l) was used and enzyme synthesis was stimulated by addition of 5 μM Cu²⁺ before inoculation, maximal laccase activities obtained in a batch cultivation were, approximately, 1000 nkat/l. Under these conditions, addition to the medium of the aromatic inducer 2,5-xylidine (1 mM) led to a 10-fold increase in laccase activity. Laccase productivity in shaken flask cultures was also enhanced (to more than 4000 nkat/l on day 3) by using a medium with the initial pH of 7.5. Such a high value of the optimal medium pH for laccase production by R. praticola is exceptional among the ligninolytic fungi. In fermenter fungal cultures supplemented with cupric ions, the highest laccase activity (about 4000 nkat/l after 3 days' cultivation) was reached after 24-h incubation using a bioreactor with the aeration rate of 2 l/min, the agitation speed of 200 rμM, and a constant medium pH of 8.0.

4

Assessment of laccase activity synthesized by Basidiomycota fungi in the presence of wood impregnated with creosote oil

72%

Betlej I., Andres B., Chludzinska D., Olszewska P., Pach E.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2022

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tom 120

5

Functional and transcriptomic characterization of a dye-decolorizing fungus from Taxus rhizosphere

72%

Hao D. C., Song S. M., Cheng Y., Qin Z. Q., Ge G. B., An B. L., Xiao P. G.

Polish Journal of Microbiology

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2018

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tom 67

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nr 4

We isolated three laccase-producing fungus strains from Taxus rhizosphere. Myrotheium verrucaria strain DJTU-sh7 had the highest laccase activity of 216.2 U/ml, which was increased to above 300 U/ml after optimization. DJTU-sh7 had the best decolorizing effect for three classes of reactive dyes. The DJTU-sh7-containing fungal consortium displayed the robust decolorizing ability. Both color removal efficiency and chemical oxygen demand were increased in the consortium mediated biotransformation. Transcriptome changes of M. verrucaria elicited by azo dye and phenolic were quantified by the high throughput transcriptome sequencing, and the activities of the selected oxidases and reductases were determined. The possible involvement of oxidases and reductases, especially laccase, aryl alcohol oxidase, and ferric reductase in the biotransformation of dye and phenolic compounds was revealed at both transcriptomic and phenotypic levels. Revealing the transcriptomic mechanisms of fungi in dealing with organic pollutants facilitates the fine-tuned manipulation of strains in developing novel bioremediation and biodegradation strategies.

6

Purification and characterization of laccase from Pleurotus tuber-regium and its application in dye decolourization

72%

Bamigboye C. O., Oloke J. K., Olaogun B., Alabi Z., Ogunbiyi D., Ogundare A., Akinloye D.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2019

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tom 100

|

nr 3

7

Laccase treatment of Norway spruce wood surface improves resistance and copper fixation of treated wood

72%

Vaukner Gabric M., Boncina T., Humar M., Pohleven F.

Drewno. Prace Naukowe. Doniesienia. Komunikaty

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2016

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tom 59

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nr 198

8

Enzymatic treatment of lignocellulosic composites for reduced toxicity

72%

Batog J., Wojcik R.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2013

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tom 81

9

Comparison of growth and enzymatic activity of mycelium and yielding of Pleurotus ostreatus (Fr.) Kumm. on different substrates

58%

Siwulski M., Drzewiecka K., Sobieralski K., Chong Y.

Acta Scientiarum Polonorum. Hortorum Cultus

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2010

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tom 09

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nr 3

Cereal straw is used as the most common substrate for Pleurotus ostreatus (Fr.) Kumm. cultivation. However other easily available and cheep materials are being sought. Textile industry wastes, among others, seem to be suitable materials. The effect of the kind of substrate on the mycelium growth, enzymatic activity and yield of Pleurotus ostreatus (Fr.) Kumm. was investigated. The subjects of the studies were the ‘K22’ and ‘P80’ strains of P. ostreatus and four substrates: i.e. alder sawdust, rye straw, hemp and flax shive. The type of substrate was found to affect the examined P. ostreatus parameters. The examined strains responded similarly to the applied substrate type. The best mycelium growth was obtained on the substrate from flax shive. The activity of the laccase enzyme turned out to be the highest on the hemp shive and the same substrate also yielded the highest crop of carpophores. The obtained results corroborated high usefulness of hemp and flax shive for the cultivation of P. ostreatus.

10

Produkcja lakkazy i jej immobilizacja na wybranych nosnikach

58%

Rekuc A., Kruczkiewicz P., Kielczynski R., Jastrzembska B., Bryjak J.

Acta Scientiarum Polonorum. Biotechnologia

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2006

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tom 05

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nr 1-2

3-15

11

Research on catecholases, laccases and cresolases in plants. Recent progress and future needs.

58%

Aniszewski T., Lieberei R., Gulewicz K.

Acta Biologica Cracoviensia. Series Botanica

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2008

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tom 50

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nr 1

Polyphenol oxidases (PPOs) reveal a range of forms and occur in all plants and crops. PPOs are comprised of three enzymes (catecholase, laccase, cresolase) with very different activities and specificities. Cresolase has a dualistic form (cresolase is only in plants and tyrosinase is only in animals and microorganisms). Very often in the literature the generic word "PPO" is used inappropriately as one enzyme. This should be avoided in future studies, as clear systematics and correct nomenclature of PPOs are needed for proper research. PPOs have different substrate specificities and typical inhibitors, and they catalyze hydroxylation and oxidation processes in plants. Pigment formation in cells and cellular systems is affected by active PPOs. Catecholases, laccases and cresolases are encoded by nuclear genes of plants. Various PPO DNA sequences have been found, and PPOs occur in multiple gene families. The protective potential of PPOs in plants and enhanced herbivory resistance is debated, and the final evidence has not yet appeared. The activity of PPOs in germination is recognized, but its mechanism is still not clear. Seed testa coloration in Arabidopsis thaliana is effected by laccase and not by catecholase. The TT10 gene encoding laccase in the Arabidopsis seed testa has been isolated. Arabidopsis genome analysis led to the identification of 16 other putative laccases and their genes, named AtLAC1 to AtLAC17 according to their position in the genome. Challenging areas of research for the future are seed testa PPOs and their mobilization in endosperm and micropylar regions, and PPOs as a part of the plant defense system and immunity.

12

Effect of chitosan coating on shelf-life and quality of fresh-cut mushroom

51%

Eissa H. A. A.

Polish Journal of Food and Nutrition Sciences

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2008

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tom 58

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nr 1

The effect of chitosan coating in fresh-cut mushroom preservation, including microbiological, enzyme activities, colour characteristics and chemical quality attributes, was examined. However, application of chitosan coating to enzyme activity control and quality maintenance of fresh-cut mushroom was investigated. Fresh-cut mushroom were treated with aqueous solution containing 5, 10 and 20 g of chitosan/1 L, placed in polyethylene bags, and then stored at 4°C. Changes in total phenolic content, and cellulase (CEL), total amylase, α and β amylase, laccase (LAC), phenylalanine ammonia lyase (PAL), peroxidase (POD), catalase (CAT) and polyphenoloxidase (PPO) enzymes activities were measured. Applications of chitosan coating delayed discoloration associated with reduced enzyme activities of LAC, PAL, POD, CAT and PPO as well as lowered total phenolic content. Also, it slowed down texture changes associated with reduced enzyme activities of CEL, total amylase and α-amylase. Results showed that increasing the concentration of chitosan coating resulted in higher contents of total soluble solids (TSS), total acidity and TSS/T acid ratio of fresh-cut mushroom. In mushroom, during storage at 4°C for 15 days, 20 g/kg chitosan coating inhibited the growth of total bacteria, yeasts and moulds counts. Chitosan also had a good effect on the evolution of the colour characteristics and parameters (C* and BI) of fresh-cut mushroom during storage at 4°C. The results showed that increasing the concentration of chitosan coating enhanced the beneficial effects of chitosan on extended shelf-life and maintained quality of fresh-cut mushroom.

Ograniczanie wyników

Combining laccase with Cu(salen) catalysts for oxidation of kraft lignin

Purification and characterization of a novel laccase from the mushroom Pleurotus nebrodensis

Effects of culture conditions on production of extracellular laccase by Rhizoctonia praticola

Assessment of laccase activity synthesized by Basidiomycota fungi in the presence of wood impregnated with creosote oil

Functional and transcriptomic characterization of a dye-decolorizing fungus from Taxus rhizosphere

Purification and characterization of laccase from Pleurotus tuber-regium and its application in dye decolourization

Laccase treatment of Norway spruce wood surface improves resistance and copper fixation of treated wood

Enzymatic treatment of lignocellulosic composites for reduced toxicity

Comparison of growth and enzymatic activity of mycelium and yielding of Pleurotus ostreatus (Fr.) Kumm. on different substrates

Produkcja lakkazy i jej immobilizacja na wybranych nosnikach

Research on catecholases, laccases and cresolases in plants. Recent progress and future needs.

Effect of chitosan coating on shelf-life and quality of fresh-cut mushroom