masterThesis
Avaliação da biodegradabilidade de petróleo utilizando microrganismos isolados do estuário do Rio Potengi (RN)
Fecha
2010-08-16Registro en:
COSTA, Cíntia de Castro. Avaliação da biodegradabilidade de petróleo utilizando microrganismos isolados do estuário do Rio Potengi (RN). 2010. 106 f. Dissertação (Mestrado em Pesquisa e Desenvolvimento em Ciência e Engenharia de Petróleo) - Universidade Federal do Rio Grande do Norte, Natal, 2010.
Autor
Costa, Cíntia de Castro
Resumen
The oil activity in the Rio Grande do Norte State (RN) is a permanent threat to coastal
ecosystems, particularly mangroves, with the possibility of oil spills. In this context, the
objective of this study was to evaluate the potential resistance of the mangrove
environment of a possible spill. Were selected and isolated microorganisms degrading
oil by the technique of enrichment cultures and formation of a bacterial consortium. The
kinetic study of the consortium was held in rotary incubator shaken at 150 rpm and 30°
C. Samples were taken at intervals of 4 hours for analysis of cell concentration and
surface tension. The biodegradation was monitored using two methods of respirometry:
manometric (OxiTop-C ®) and conductivimetry, where the biodegradation of oil was
estimated indirectly by oxygen consumption and CO2 production, respectively.
Furthermore, it was used a full 2² factorial design with triplicate at central point to the
runs that used the conductivimetric methodology.. The technique of enrichment cultures
allowed to obtain thirteen bacterial strains. Kinetic study of the consortium, we can
showed the absence of the lag phase, reaching a maximum cell concentration of 2.55 g /
L at 16 h of cultivation and a reduction on surface tension. When we adopted the
methodology of OxiTop-C was detected a band indicating biodegradability (1% oil v/v),
however when we used the conductivimetry methodology did not observe any band that
would indicate effective biodegradation. By monitoring a process of biodegradation is
necessary to observe the methodology will be adopted to evaluate the biodegradation
process, since for the same conditions adopted different methodologies can produce
different results. The oil-degrading isolates from soils of the mangrove estuary Potengi /
RN are largely to be used in bioremediation strategies of these places, in the case of a
possible oil spill, or it can be used in the treatment of waste oil generated in saline
environments, since they are optimized the conditions of the tests so that the efficiency
of biodegradation reach the minimum level suggested by the standarts