title: Isolation and bioelectrochemical characterization of novel fungal sources with oxidasic activity applied in situ for the cathodic oxygen reduction in microbial fuel cells.
abstract: Brazilian filamentous fungi Rhizopus sp. (SIS-31), Aspergillus sp. (SIS-18) and Penicillium sp. (SIS-21), sources of oxidases were isolated from Caatinga's soils and applied during the in situ cathodic oxygen reduction in fuel cells. All strains were cultivated in submerged cultures using an optimized saline medium enriched with 10 g L(-1) of glucose, 3.0 g L(-1) of peptone and 0.0005 g L(-1) of CuSO4 as enzyme inducer. Parameters of oxidase activity, glucose consumption and microbial growth were evaluated. In-cell experiments evaluated by chronoamperometry were performed and two different electrode compositions were also compared. Maximum current densities of 125.7, 98.7 and 11.5 μA cm(-2) were observed before 24 h and coulombic efficiencies of 56.5, 46.5 and 23.8% were obtained for SIS-31, SIS-21 and SIS-18, respectively. Conversely, maximum power outputs of 328.73, 288.80 and 197.77 mW m(-3) were observed for SIS-18, SIS-21 and SIS-31, respectively. This work provides the primary experimental evidences that fungi isolated from the Caatinga region in Brazil can serve as efficient biocatalysts during the oxygen reduction in air-cathodes to improve electricity generation in MFCs.
authors.affiliation: NPCIAMB - Núcleo de Pesquisas em Ciências Ambientais e Biotecnologia, Centro de Ciências e Tecnologia (CCT), Universidade Católica de Pernambuco - UNICAP, Rua Nunes Machado, 42, Bloco J, Térreo, Boa Vista, 50050-590 Recife, Pernambuco, Brazil(1).
authors.forename: Kyriale Vasconcelos
authors.initials: KV
authors.lastname: Morant
authors.affiliation: NPCIAMB - Núcleo de Pesquisas em Ciências Ambientais e Biotecnologia, Centro de Ciências e Tecnologia (CCT), Universidade Católica de Pernambuco - UNICAP, Rua Nunes Machado, 42, Bloco J, Térreo, Boa Vista, 50050-590 Recife, Pernambuco, Brazil(1).
authors.forename: Paulo Henrique
authors.initials: PH
authors.lastname: da Silva
authors.affiliation: NPCIAMB - Núcleo de Pesquisas em Ciências Ambientais e Biotecnologia, Centro de Ciências e Tecnologia (CCT), Universidade Católica de Pernambuco - UNICAP, Rua Nunes Machado, 42, Bloco J, Térreo, Boa Vista, 50050-590 Recife, Pernambuco, Brazil(1).
authors.forename: Galba Maria
authors.initials: GM
authors.lastname: de Campos-Takaki
authors.affiliation: NPCIAMB - Núcleo de Pesquisas em Ciências Ambientais e Biotecnologia, Centro de Ciências e Tecnologia (CCT), Universidade Católica de Pernambuco - UNICAP, Rua Nunes Machado, 42, Bloco J, Térreo, Boa Vista, 50050-590 Recife, Pernambuco, Brazil(1). Electronic address: camilo.larotta@pq.cnpq.br.
authors.forename: Camilo Enrique La Rotta
authors.initials: CE
authors.lastname: Hernández
mesh_terms: D001230:Aspergillus / Q000201:enzymology / Q000302:isolation & purification; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D001938:Brazil; D055664:Electrochemical Techniques; D004566:Electrodes; D005656:Fungal Proteins / Q000378:metabolism*; D005658:Fungi / Q000201:enzymology* / Q000302:isolation & purification*; D005947:Glucose / Q000378:metabolism; D007218:Industrial Microbiology; D010088:Oxidoreductases / Q000378:metabolism*; D010100:Oxygen; D010407:Penicillium / Q000201:enzymology / Q000302:isolation & purification; D012233:Rhizopus / Q000201:enzymology / Q000302:isolation & purification; D012988:Soil Microbiology
chemical_list: D005656:Fungal Proteins; D010088:Oxidoreductases; D005947:Glucose; D010100:Oxygen
keywords: Biocathodes; Biofuel cells; Cathodic oxygen reduction; Filamentous fungi; Oxidases