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Mimetic Phenoloxidase Activity: Lignin And Chlorolignin Degradation With Low Molecular Weight Chelators
Registro en:
Proceedings Of The International Conference On Biotechnology In The Pulp And Paper Industry. Cppa, Montreal, Canada, v. 2, n. , p. B163 - B166, 1998.
2-s2.0-0031677274
Autor
Duran Nelson
Santiago Mariangela
Parra Carolina
Rodriguez Jaime
Institución
Resumen
The use of natural chelating agents produced by fungi and bacteria that are called siderophores shows a high affinity constant for metals like iron represents a good alternative for resolving the problems associated with the potential environmental impact produced by synthetic chelators such as EDTA or DTPA. In the study of phenoloxidase activity, the pH, ionic strength (μ), temperature and o-dianisidine conditions were optimized. The properties of four model siderophores, desferrioxamine (DB), acetohydroxamic acid (AHA), 2,3-dihydroxybenzoic acid (DHBA) and 3,4-dihydroxyphenyl acetic acid (DHPAA) were studied. At 2:1 DB/Fe(III), 1:1 AHA/Fe(III), 2:1 DHPAA/Fe(III) and 1:1.5 DHBA/Fe(III), the maximum phenoloxidase activities acting on o-dianisidine were observed. A mechanistic study showed that with these conditions all models of siderophores are able to reduce Fe(III) to Fe(II) followed by ferrozine/ o-phenantroline complexation with Fe(II). Isolated lignin and chlorolignins from Kraft E1 effluents were degraded in the presence of all the metal complexes. 2
B163 B166