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Influence of very low doses of mediators on fungal laccase activity - nonlinearity beyond imagination.

Malarczyk E, Kochmanska-Rdest J, Jarosz-Wilkolazka A - Nonlinear Biomed Phys (2009)

Bottom Line: Two high laccase-producing fungal strains, Trametes versicolor and Cerrena unicolor, were used in this study as a source of enzyme.Selected dilutions of the mediators significantly increased the activity of extracellular laccase during 14 days of cultivation what was distinctly visible in PAGE technique and in colorimetric tests.The same mediator dilutions increased demethylation properties of laccase, which was demonstrated during incubation of enzyme with veratric acid.

View Article: PubMed Central - HTML - PubMed

Affiliation: Biochemistry Department, Maria Curie-Skłodowska University, Lublin, Poland. malar@poczta.umcs.lublin.pl.

ABSTRACT
Laccase, an enzyme responsible for aerobic transformations of natural phenolics, in industrial applications requires the presence of low-molecular substances known as mediators, which accelerate oxidation processes. However, the use of mediators is limited by their toxicity and the high costs of exploitation. The activation of extracellular laccase in growing fungal culture with highly diluted mediators, ABTS and HBT is described. Two high laccase-producing fungal strains, Trametes versicolor and Cerrena unicolor, were used in this study as a source of enzyme. Selected dilutions of the mediators significantly increased the activity of extracellular laccase during 14 days of cultivation what was distinctly visible in PAGE technique and in colorimetric tests. The same mediator dilutions increased demethylation properties of laccase, which was demonstrated during incubation of enzyme with veratric acid. It was established that the activation effect was assigned to specific dilutions of mediators. Our dose-response dilution process smoothly passes into the range of action of homeopathic dilutions and is of interest for homeopaths.

No MeSH data available.


Related in: MedlinePlus

Changes in the activity (A) and isozymic patterns (B) of extracellular laccase in media of Trametes versicolor cultivated 14 days with 10 dilutions of ABTS. On PAGE slab (B) the dilutions No 1 and 2 was omitted; c (ctrl) - control. PAGE slab stained with guaiacol.
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Figure 4: Changes in the activity (A) and isozymic patterns (B) of extracellular laccase in media of Trametes versicolor cultivated 14 days with 10 dilutions of ABTS. On PAGE slab (B) the dilutions No 1 and 2 was omitted; c (ctrl) - control. PAGE slab stained with guaiacol.

Mentions: Two milliliters of 14 days culture media or pure laccase solution with the beginning activity 20 nkatals/ml were incubated with one ml of 2% potasium veratrate during 4 hours in the presence of 200 μl selected dilutions of HBT or ABTS, chosen according to PAGE results from Fig 1, 2, 3, 4, 5. The selected dilutions of HBT (n = 5 and 11) and ABTS (n = 6 and 12) were used respectively according to their maximal and minimal action on the laccase activity. The progress of veratrate demethylation was assayed spectrophotometrically based on a colorimetric reaction of vanillates [35] which are the main product of veratrate demethylation. After incubation, the rapid colorimetric reaction with DASA reagents was run and 0.2 ml of each sample was mixed with 0.2 ml of 2% sulphanilamide solution in 10% HCl followed by addition of 0.2 ml of 5% NaNO3. The mixture was neutralized with 1 ml of 20% Na2CO3, and absorbance at 500 nm was measured. The % of progress in veratrate demethylation was calculated with the calibration curve for vanillic acids (y = 6.85x- 0.0128, R2 = 0,999).


Influence of very low doses of mediators on fungal laccase activity - nonlinearity beyond imagination.

Malarczyk E, Kochmanska-Rdest J, Jarosz-Wilkolazka A - Nonlinear Biomed Phys (2009)

Changes in the activity (A) and isozymic patterns (B) of extracellular laccase in media of Trametes versicolor cultivated 14 days with 10 dilutions of ABTS. On PAGE slab (B) the dilutions No 1 and 2 was omitted; c (ctrl) - control. PAGE slab stained with guaiacol.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2749849&req=5

Figure 4: Changes in the activity (A) and isozymic patterns (B) of extracellular laccase in media of Trametes versicolor cultivated 14 days with 10 dilutions of ABTS. On PAGE slab (B) the dilutions No 1 and 2 was omitted; c (ctrl) - control. PAGE slab stained with guaiacol.
Mentions: Two milliliters of 14 days culture media or pure laccase solution with the beginning activity 20 nkatals/ml were incubated with one ml of 2% potasium veratrate during 4 hours in the presence of 200 μl selected dilutions of HBT or ABTS, chosen according to PAGE results from Fig 1, 2, 3, 4, 5. The selected dilutions of HBT (n = 5 and 11) and ABTS (n = 6 and 12) were used respectively according to their maximal and minimal action on the laccase activity. The progress of veratrate demethylation was assayed spectrophotometrically based on a colorimetric reaction of vanillates [35] which are the main product of veratrate demethylation. After incubation, the rapid colorimetric reaction with DASA reagents was run and 0.2 ml of each sample was mixed with 0.2 ml of 2% sulphanilamide solution in 10% HCl followed by addition of 0.2 ml of 5% NaNO3. The mixture was neutralized with 1 ml of 20% Na2CO3, and absorbance at 500 nm was measured. The % of progress in veratrate demethylation was calculated with the calibration curve for vanillic acids (y = 6.85x- 0.0128, R2 = 0,999).

Bottom Line: Two high laccase-producing fungal strains, Trametes versicolor and Cerrena unicolor, were used in this study as a source of enzyme.Selected dilutions of the mediators significantly increased the activity of extracellular laccase during 14 days of cultivation what was distinctly visible in PAGE technique and in colorimetric tests.The same mediator dilutions increased demethylation properties of laccase, which was demonstrated during incubation of enzyme with veratric acid.

View Article: PubMed Central - HTML - PubMed

Affiliation: Biochemistry Department, Maria Curie-Skłodowska University, Lublin, Poland. malar@poczta.umcs.lublin.pl.

ABSTRACT
Laccase, an enzyme responsible for aerobic transformations of natural phenolics, in industrial applications requires the presence of low-molecular substances known as mediators, which accelerate oxidation processes. However, the use of mediators is limited by their toxicity and the high costs of exploitation. The activation of extracellular laccase in growing fungal culture with highly diluted mediators, ABTS and HBT is described. Two high laccase-producing fungal strains, Trametes versicolor and Cerrena unicolor, were used in this study as a source of enzyme. Selected dilutions of the mediators significantly increased the activity of extracellular laccase during 14 days of cultivation what was distinctly visible in PAGE technique and in colorimetric tests. The same mediator dilutions increased demethylation properties of laccase, which was demonstrated during incubation of enzyme with veratric acid. It was established that the activation effect was assigned to specific dilutions of mediators. Our dose-response dilution process smoothly passes into the range of action of homeopathic dilutions and is of interest for homeopaths.

No MeSH data available.


Related in: MedlinePlus