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| Author(s): |
Maricy Raquel Lindenbah Bonfá
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia de Alimentos |
| Defense date: | 2009-01-28 |
| Examining board members: |
Lúcia Regina Durrant;
Marta Cristina Teixeira Duarte;
Fabiana Fantinatti Garboggini;
Rose Marry Araujo Gondim Tomaz;
Marcia Freire dos Reis
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| Advisor: | Lúcia Regina Durrant |
| Abstract | |
The halophilic microorganisms are those able to live in saline environments. Among them are, for example, halophilic bacteria and haloarchaea. These two classes of organisms have been the aim of study of this Project. These microorganisms were tested for their ability to degrade monoaromatic and polyaromatic compounds. The capacity of degradation of these compounds by halophilic microorganisms is extremely important because saline environments are subject to contamination by toxic compounds, and many industrial effluents, such as the wastewater of oil production have high salinity. The strains of haloarchaea tested here were able to grow and degrade aromatic acids as sole source of carbon and energy. There was a decrease in the degradation when 0.05% of yeast extract was added. These same strains were also able to degrade PAHs in the presence of 0.05% of yeast extract. Primers were used for the amplification of genes that synthesize catechol 1,2-dioxygenase, protocatecuate 3,4-dioxygenase and gentisate 1,2-dioxygenase. Halococcus morhuaea was the only strain showing the gene for gentisate 1,2-dioxigenase. The haloarchaea strains were identified by amplification and sequencing of the 16S rRNA gene and were identified as belonging to the genus Haloferax. Seven haloarchaea strains were isolated from samples collected in Brazil (Nossa Senhora do Socorro-SE and Arraial do Cabo-RJ), one of them was identified as Halosarcina pallida. Two halophilic bacterial strains were isolated in medium containing 3 mM phenol as the sole source of carbon and energy, strain HU, which was isolated from a contaminated region of salt marsh in Huelva, Spain and strain AP isolated from wastewater from oil production (Petrobras / Sao Sebastiao-SP). These two strains were identified as Modicisalibacter tunisiensis and Arhodomonas aquaeolei, respectively. The two strains and Halomonas organivorans demonstrated the ability to degrade phenol. HU degraded 3 mM of phenol after 72 hours. These three strains have the genes for the enzyme catechol 1,2-dixiogenase and protocatecuato 3,4-dioxygenase. All the halophilic bacteria and haloarchaea strains were used for bioremediation of water from oil production and reduced the COD of effluent. Among the haloarchaea, strain AA31 promoted the highest reduction of COD present in the natural effluent (87.47%). Among the bacteria H. organivorans promoted the highest reduction of COD of the effluent (89.5%). These results demonstrate the great potential for degradation of aromatic compounds by the strains studied, as well as for the bioremediation of water produced during oil production (AU) | |