Oxalic acid, versatile peroxidase secretion and chelating ability of Bjerkandera fumosa in rich and limited culture conditions

Efficient ligninolytic systems of wood-degrading fungi include not only oxidizing enzymes, but also low-molecular-weight effectors. The ability of Bjerkandera fumosa to secrete oxalic acid and versatile peroxidase (VP) in nitrogen-rich and nitrogen-limited media was studied. Higher activity of VP was determined in the nitrogen-limited media but greater concentration of oxalic acid was observed in the cultures of B. fumosa without nitrogen limitation. Ferric ions chelating ability of Bjerkandera fumosa studied in ferric ions limited media was correlated with the increased level of oxalic acid. The presence of hydroxamate-type siderophores in B. fumosa media were also detected. Oxalate decarboxylase was found to be responsible for regulation of oxalic acid concentration in the tested B. fumosa cultures

Nonlinear changes in the activity of the oxygen-dependent demethylase system in Rhodococcus erythropolis cells in the presence of low and very low doses of formaldehyde

The effect of exogenous, highly diluted formaldehyde on the rate of demethylation/re-methylation of veratric acid by the bacteria Rhodococcus erythropolis was studied using electrophoretic and microscopic techniques. The activity of 4-O-demethylase, responsible for accumulation of vanillic acid, and the levels of veratric and vanillic acids were determined using capillary electrophoresis. Formaldehyde was serially diluted at 1:100 ratios, and the total number of iterations was 20. After incubation of the successive dilutions of formaldehyde with the bacteria, demethylase activity oscillated in a sinusoidal manner. It was established using capillary electrophoresis that methylation of vanillic acid to veratric acid occurred at a double rate, as shown by the doubled fluctuation in the concentration of veratrate. There were also changes in the NADH oxidase activity, which is associated with methylation processes. Microscopic observations revealed the presence of numerous enlarged vacuoles in bacterial cells during the accumulation of large amounts of vanillic acid, and their disappearance together with a decrease in 4-O-demethylase activity. The presented results give evidence for the ability of living cells to detect the presence of submolecular concentrations of biological effectors in their environment and provide a basis for a scientific explanation of the law of hormesis and the therapeutic effect of homeopathic dilutions

Synthesis of dyes using immobilized fungal biomass

Grzyby białej zgnilizny drewna cechuje naturalna zdolność wydzielania zewnątrzkomórkowych oksydoreduktaz o właściwościach lignino-litycznych. Do nich należy lakaza, enzym katalizujący syntezę różnego typu związków. Celem pracy było zastosowanie unieruchomionej biomasy grzybów wydzielających lakazę do syntezy barwników.Application of whole-cell-mediated reactions in white biotechnology represents a promising alternative to chemical synthesis of products of commercial importance. The goal of this paper was to present potential application of fungal biomass, focusing specifically on their use as biocatalysts in environmental friendly synthesis of new molecules

Immobilized fungal biomass as biocatalyst for the synthesis of textile dyes

Hodowle grzybów ligninolitycznych, o naturalnej zdolności wydzielania lakazy wykazują ogromny potencjał aplikacyjny w syntezie m.in. barwników tekstylnych. Biotransformacja związków przez grzyby zachodzi in situ, nie wymaga kosztownego i czasochłonnego procesu pozyskiwania i oczyszczania enzymu. Dodatkowe związanie biomasy na trwałym nośniku wykonanym np. z żyłki polipropylenowej, ogranicza swobodną migrację komórek i umożliwia działanie układu w systemie ciągłej syntezy.White rot fungal cultures, with natural capacity of laccase secretion, have a great potential application in the synthesis of textile dyes. The biotransformation of compounds by fungal biomass occurs in situ and does not require expensive and time-consuming process of enzyme purification. Additional immobilization of biomass on a plastic mesh scourer limited free migration of cells and allows the operation of this system during continuous synthesis

Purification of fungal polysaccharides using chromatographic methods

Celem pracy było opracowanie metody pozyskiwania i oczyszczania zewnątrzkomórkowych polisacharydów ze szczepu Ganoderma applanatum z wykorzystaniem metod chromatograficznych. Surowy preparat polisacharydu poddawano analizie chromatograficznej z wykorzystaniem nośników Sepharose 6B lub Sepharose CI-4B uzyskując trzy symetryczne piki elucji. Frakcje polisacharydowe nie wykazywały absorbancji przy długości fali 280 i 260 nm co świadczy o braku białek i kwasów nukleinowych w badanych substancjach.The aim of this work was to study the production of exopolysaccharides from Ganoderma applanatum and the description of chromatographic methoc purification of fungal polysaccharides. Crude polysaccharides were fractionated using preparative Sepharose 6B or Sepharose CI-4B chromatography obtain three fractions, which were selected on the total carbohydrate elution profile. Polysaccharides fractions had no absorbance at 280 and 260 nm UV spectrum, indicating the absence of proteins and nucleic acids

Synthesis, purification and characterization of bioflocculants isolated from bacterial strains

Badania obejmowały wstępne oczyszczanie bakteryjnych bioflokulantów oraz porównanie aktywności flokulacyjnej w obrębie analizowanych szczepów. Stwierdzono, że szczepy bakteryjne należące do Actinobacteria syntetyzują bioflokulanty o wysokiej aktywności flokulacyjnej, której nie tracą w wyniku oczyszczania. Wysoka aktywność wyizolowanych biopolimerów pozwoli na wydajne ich wykorzystanie w przemyśle i medycynie.An appropriate purification method of bacterial bioflocculants was selected and flocculating activities of studied strains were compared. Studies showed that bacterial strains from Actinobacteria can synthesise bioflocculants with high flocculating activity which is very stable during purification process. The high activity of isolated biopolymers will enable their efficient application in industry and medicine

Analysis of the efficiency and specificity of the synthetic serine protease inhibitor immobilization process using capillary electrophoresis

Przedstawiono proces immobilizacji syntetycznego inhibitora proteaz serynowych AEBSF, który należy do rodziny związków benzosulfonowych. Zastosowanie techniki elektroforezy kapilarnej do celów analizy ilościowej pozwoliło na przeprowadzenie szybkiego pomiaru, charakteryzującego się wysoką specyficznością i precyzją. Na podstawie uzyskanych wyników stwierdzono, że inhibitor AEBSF, poddawany procesowi kowalencyjnej immobilizacji, jest efektywnie wiązany do porowatego nośnika. Jednocześnie określono, że wiąże się on z matrycą także wiązaniami adsorpcyjnymi i hydrofobowymi.The paper describes a method of immobilization of AEBSF synthetic protease inhibitor which belongs to the family of benzensulfonyl compounds. The application of capillary electrophoresis for a quantitative analysis allows one to perform high-speed measurement characterized by high specificity and repeatability. The obtained results allowed one to confirm that the AEBSF inhibitor under covalent immobilization process is effectively bound to the porous support. It was also determined that AEBSF inhibitor binds to the matrix by adsorption and hydrophobic bonds