title: Isolation of autochthonous non-white rot fungi with potential for enzymatic upgrading of Venezuelan extra-heavy crude oil.
abstract: The increasing world demand for fuels makes it necessary to exploit the largest reserve of extra-heavy crude oil (EHCO) of the Orinoco Oil Belt from Venezuela. We propose the use of extracellular oxidative enzymes, in particular, lignin-degrading enzyme systems (LDS) of fungi, for enzymatic improvement of EHCO. Autochthonous non-white rot fungal strains able to use EHCO, and several polycyclic aromatic hydrocarbons (PAHs) as sole carbon source and energy, were isolated from EHCO-polluted soils and identified as belonging to the genera Fusarium, Penicillium , Trichoderma , Aspergillus , Neosartorya, Pseudallescheria, Cladosporium, Pestalotiopsis , Phoma and Paecillomyces. Phenotypic and biochemical assays revealed the ability of these filamentous fungi to synthesize extracellular oxidative enzymes, and suggested a relationship between the LDS and EHCO bioconversion. This work reports, for the first time, the use of o-phenylenediamine dihydrochloride (OPD) as substrate to measure extracellular ligninolytic peroxidases (ELP) in culture broths of filamentous fungi (Fusarium solani HP-1), and constitutes the first formal study of the fungal community associated with the EHCO of the Orinoco Oil Belt.
authors.affiliation: Unidad de Biotecnología del Petróleo, Centro de Biotecnología, Fundación Instituto de Estudios Avanzados (IDEA), C/Hoyo de la Puerta-Baruta, Sartenejas, Caracas 1080, Venezuela.
authors.forename: Leopoldo
authors.initials: L
authors.lastname: Naranjo
authors.forename: Hector
authors.initials: H
authors.lastname: Urbina
authors.forename: Angela
authors.initials: A
authors.lastname: De Sisto
authors.forename: Vladimir
authors.initials: V
authors.lastname: Leon