The effect of pH on the transformation of syringic and vanillic acids by the laccases of Rhizoctonia praticola and Trametes versicolor

Improvement of the Antifungal Activity Against Botrytis Cinerea of Syringic Acid, a Phenolic Acid From Grape Pomace

“…The different yields in dimer production could be attributed to differences in reaction conditions and also in the laccase used. It has been reported that these enzymes have different optimal pH, and the products formed may vary using a different pH in the reaction 29 . Table 2.…”

Oxygen Activation during Oxidation of Methoxyhydroquinones by Laccase from Pleurotus eryngii

“…This way, lignin mineralization can be accomplished by as-yet-uncharacterized intracellular processes. Another source of quinones is the large amount of white-rot fungi-produced methoxylated and hydroxylated aromatic metabolites (22,46), which are substrates of the ligninolytic enzymes (23,34). Quinones are usually reduced to hydroquinones when they are in contact with whiterot fungi mycelium (7,45).…”

Role of a Laccase in the Degradation of Pentachlorophenol

“…versicolor was extant in the collection of the Laboratory of Soil Biochemistry and maintained on potato dextrose agar slants at 4°C. Unless otherwise stated, the culture medium employed in experiments contained (g/l): KCl, 0.5; MgSO 4 .7H 2 O, 0.5; KH 2 PO 4 , 0.45; Na 2 HPO 4 , 0.17; NaNO 3 0.15; sucrose, 10; l-asparagine, 0.125 and the following micronutrients (mg/l): MnCl 2 ·4H 2 O, 10; FeCl 3 ·6H 2 O, 5; ZnCI 2 , 2; CaCl 2 ·2H 2 O, 73.5; CuSO 4 ·5H 2 O, 4; NaB 4 O 7 .10H 2 O, 2; NaMoO 4 ·2H 2 O, 4; thiamine HCI, 0.05 (Leonowicz et al 1984). Final pH was 5.5.…”

“…Autoclaved fungal cultures, supplemented with active laccase and laccase inactivated by autoclaving, served as controls. The laccase was isolated from T. versicolor according to the procedure of Leonowicz et al (1984). Laccase activity was determined by the oxidation of ABTS (Bourbonnais and Paice 1992).…”