title: A High Redox Potential Laccase from Pycnoporus sanguineus RP15: Potential Application for Dye Decolorization.
abstract: Laccase production by Pycnoporus sanguineus RP15 grown in wheat bran and corncob under solid-state fermentation was optimized by response surface methodology using a Central Composite Rotational Design. A laccase (Lacps1) was purified and characterized and the potential of the pure Lacps1 and the crude culture extract for synthetic dye decolorization was evaluated. At optimal conditions (eight days, 26 °C, 18% (w/w) milled corncob, 0.8% (w/w) NH₄Cl and 50 mmol·L(-1) CuSO₄, initial moisture 4.1 mL·g(-1)), the laccase activity reached 138.6 ± 13.2 U·g(-1). Lacps1 was a monomeric glycoprotein (67 kDa, 24% carbohydrate). Optimum pH and temperature for the oxidation of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonate) (ABTS) were 4.4 and 74.4 °C, respectively. Lacps1 was stable at pH 3.0-8.0, and after two hours at 55-60 °C, presenting high redox potential (0.747 V vs. NHE). ABTS was oxidized with an apparent affinity constant of 147.0 ± 6.4 μmol·L(-1), maximum velocity of 413.4 ± 21.2 U·mg(-1) and catalytic efficiency of 3140.1 ± 149.6 L·mmol(-1)·s(-1). The maximum decolorization percentages of bromophenol blue (BPB), remazol brilliant blue R and reactive blue 4 (RB4), at 25 or 40 °C without redox mediators, reached 90%, 80% and 60%, respectively, using either pure Lacps1 or the crude extract. This is the first study of the decolorization of BPB and RB4 by a P. sanguineus laccase. The data suggested good potential for treatment of industrial dye-containing effluents.
authors.affiliation: Department of Chemistry, Faculty of Philosophy, Sciences and Languages of Ribeirão Preto, University of São Paulo, Bandeirantes Avenue, 3900, Ribeirão Preto, SP 14040-901, Brazil. luccilatorre@usp.br.
authors.forename: Ana L R L
authors.initials: AL
authors.lastname: Zimbardi
authors.affiliation: Department of Chemistry, Faculty of Philosophy, Sciences and Languages of Ribeirão Preto, University of São Paulo, Bandeirantes Avenue, 3900, Ribeirão Preto, SP 14040-901, Brazil. priscila@lcp.inpe.br.
authors.forename: Priscila F
authors.initials: PF
authors.lastname: Camargo
authors.affiliation: Department of Chemistry, Faculty of Philosophy, Sciences and Languages of Ribeirão Preto, University of São Paulo, Bandeirantes Avenue, 3900, Ribeirão Preto, SP 14040-901, Brazil. sibelicarli@usp.br.
authors.forename: Sibeli
authors.initials: S
authors.lastname: Carli
authors.affiliation: Department of Chemistry, Faculty of Philosophy, Sciences and Languages of Ribeirão Preto, University of São Paulo, Bandeirantes Avenue, 3900, Ribeirão Preto, SP 14040-901, Brazil. netaoaquino@gmail.com.
authors.forename: Sidney
authors.initials: S
authors.lastname: Aquino Neto
authors.affiliation: Department of Chemistry, Faculty of Philosophy, Sciences and Languages of Ribeirão Preto, University of São Paulo, Bandeirantes Avenue, 3900, Ribeirão Preto, SP 14040-901, Brazil. luanapm@usp.br.
authors.forename: Luana P
authors.initials: LP
authors.lastname: Meleiro
authors.affiliation: Department of Molecular and Cell Biology and Protein Chemistry Center, CTC-Center for Cell Therapy-CEPID-FAPESP-Hemocentro de Ribeirão Preto, Ribeirão Preto Medical School, University of São Paulo, Bandeirantes Avenue, 3900, Ribeirão Preto, SP 14040-901, Brazil. jcrosa@fmrp.usp.br.
authors.forename: Jose C
authors.initials: JC
authors.lastname: Rosa
authors.affiliation: Department of Chemistry, Faculty of Philosophy, Sciences and Languages of Ribeirão Preto, University of São Paulo, Bandeirantes Avenue, 3900, Ribeirão Preto, SP 14040-901, Brazil. ardandra@ffclrp.usp.br.
authors.forename: Adalgisa R
authors.initials: AR
authors.lastname: De Andrade
authors.affiliation: Department of Biology, Faculty of Philosophy, Sciences and Languages of Ribeirão Preto, University of São Paulo, Bandeirantes Avenue, 3900, Ribeirão Preto, SP 14040-901, Brazil. joajorge@ffclrp.usp.br.
authors.forename: João A
authors.initials: JA
authors.lastname: Jorge
authors.affiliation: Department of Chemistry, Faculty of Philosophy, Sciences and Languages of Ribeirão Preto, University of São Paulo, Bandeirantes Avenue, 3900, Ribeirão Preto, SP 14040-901, Brazil. rosapmfi@ffclrp.usp.br.
authors.forename: Rosa P M
authors.initials: RP
authors.lastname: Furriel
mesh_terms: D052160:Benzothiazoles / Q000737:chemistry; D004396:Coloring Agents / Q000737:chemistry*; D005285:Fermentation; D005656:Fungal Proteins / Q000378:metabolism*; D042845:Laccase / Q000378:metabolism*; D010084:Oxidation-Reduction; D055494:Pycnoporus / Q000201:enzymology* / Q000254:growth & development; D013451:Sulfonic Acids / Q000737:chemistry
chemical_list: D052160:Benzothiazoles; D004396:Coloring Agents; D005656:Fungal Proteins; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D042845:Laccase
keywords: Pycnoporus sanguineus; Reactive blue 4; bromophenol blue; characterization; decolorization; laccase; purification; remazol brilliant blue R; response surface methodology; solid state fermentation