INVESTIGADORES
DELGADO Osvaldo Daniel
artículos
Título:
Microbial characterization and hydrocarbon biodegradation potential of natural bilge waste microflora.
Autor/es:
OLIVERA N; COMMENDATORE M G; DELGADO O; ESTEVES J L
Revista:
JOURNAL OF INDUSTRIAL MICROBIOLOGY & BIOTECHNOLOGY
Editorial:
Springer
Referencias:
Lugar: Londres; Año: 2003 vol. 30 p. 542 - 548
ISSN:
1367-5435
Resumen:
Shipping operations produce oily wastes that must
be managed properly to avoid environmental pollution. The aim of this study was
to characterize microorganisms occurring in ship bilge wastes placed in open
lagoons and, particularly, to assess their potential to degrade polycyclic
aromatic hydrocarbons (PAHs). A first-order kinetic was suitable for describing
hydrocarbon biodegradation after 17 days of treatment. The calculated rate
constants were 0.0668 and 0.0513 day)1with a corresponding half-life of 10.3 and
13.5 days for the aliphatic and aromatic hydrocarbon fractions, respectively.
At day 17, PAH removal percentages were: acenaphtylene 100, .uorene 95.2,
phenanthrene 93.6, anthracene 70.3, and pyrene 71.5. Methyl phenanthrene removals
were lower than that of their parent compound (3-methyl phenanthrene 83.6,
2-methyl phenanthrene 80.8, 1-methyl phenanthrene 77.3, 9-methyl phenanthrene 75.1,
and 2,7-dimethyl phenanthrene 76.6). Neither pure cultures nor the microbial
community from these wastes showed extracellular biosurfactant production suggesting
that the addition of an exogenously produced biosurfactant may be important in
enhancing hydrocarbon bioavailability and biodegradation. DNA analysis of bilge
waste samples revealed a ubiquitous distribution of the nahAc genotype in the dump pools. Although almost all of the
isolates grew on naphthalene as sole carbon source, only some of them yielded nahAc amplification under the experimental conditions used. The
variety of PAHs in bilge wastes could support bacteria with multiple
degradation pathways and a diversity of catabolic genes divergent from the
classical nah-like type.