Biodegrada????o de Hidrocarbonetos Polic??clicos Arom??ticos (HPA) por rizobact??ria em solo de v??rzea da Amaz??nia contaminado com ??leo diesel

Autor: Saraiva, L??via Ant??nia de Mello
Přispěvatelé: Oliveira, Tereza Cristina Souza de, Wiedemann, Larissa Silveira Moreira, Machado, Ana L??cia Soares
Jazyk: portugalština
Rok vydání: 2018
Předmět:
Zdroj: Biblioteca Digital de Teses e Dissertações da UFAM
Universidade Federal do Amazonas (UFAM)
instacron:UFAM
Popis: Submitted by Divis??o de Documenta????o/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-06-20T18:27:12Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Disserta????o_L??via Saraiva.pdf: 2509123 bytes, checksum: bb7298d31365da46681c004f463bd2f9 (MD5) Approved for entry into archive by Divis??o de Documenta????o/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-06-20T18:27:27Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Disserta????o_L??via Saraiva.pdf: 2509123 bytes, checksum: bb7298d31365da46681c004f463bd2f9 (MD5) Made available in DSpace on 2018-06-20T18:27:27Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Disserta????o_L??via Saraiva.pdf: 2509123 bytes, checksum: bb7298d31365da46681c004f463bd2f9 (MD5) Previous issue date: 2018-05-21 The leakage or release of diesel oil in soil and in hydric bodies, due to its composition by toxic compounds such as polycyclic aromatic hydrocarbons (PAH), may lead to changes in the environmental quality of the affected matrices. In this sense, bioremediation has been a well studied technique, considering the existence of many microorganisms that present a degradation capacity of such contaminants. The rhizobacterias, which have a high production capacity for biosurfactants, become a viable alternative because they are non-pathogenic microorganisms and thus safe to plants and animals. Therefore, considering that floodplain soils are regions that are subject to the petroleum derivatives contamination, and considering that rhizobacteria are species that are present in this soil type and can aid in the degradation process, the aim study proposed the determination of the individual PAH biodegradation potential of five isolates of rhizobacteria, and of the consortium of this five species, in samples of floodplain of amazon contaminated with diesel oil. For this, an experiment was carried out using the microbial suspension with 1 ?? 107 UFC.mL-1 of each bacterial type and the consortium in 500 g of autoclaved soil and diesel oil as carbon source. In addition, were done two samples control: (A) 500 g of autoclaved soil and diesel oil and (B) 500 g of natural soil and diesel oil. After the experiment was set up, the samples were collected for PAH determination at the times zero, 48 hours, 5, 10, 15 and 21 days. After 21 days of the experimentation, the bacteria INPA R574 and INPA 598 degraded 57.37% and 41.53%, respectively, of ??PAH, while the others had an increase in concentration of ??PAH. After 2 days, when the best degradation rates were observed, the specie INPA R574 was the microorganism that most stood out. In the treatment of ??PAH, this bacterium degraded 62.15%, while, individually, it reduced the concentrations of acenaphtene, phenanthrene and benzo(a)pyrene in 86.47%, 44.65% and 79.72% respectively. In the same time, the consortium presented rates of degradation of 64.36%, higher value, however close to the individual rate of INPA R574. The INPA R548 microorganism did not significantly contribute to the degradation of any of the contaminants studied, as well as ??PAH. The control sample (A) showed relevant degradation rates, suggesting the nutrients added to the control favored the growth of native soil bacteria that were able to degrade the PAH of the diesel added to the samples. O vazamento ou derramamento de ??leo diesel em solo e corpos h??dricos, devido sua composi????o por compostos t??xicos como os hidrocarbonetos polic??clicos arom??tico (HPA), pode levar ?? altera????o da qualidade ambiental das matrizes atingidas. Nesse sentido a biorremedia????o tem sido uma t??cnica bastante estudada, considerando a exist??ncia de muitos microrganismos que apresentam efici??ncia na degrada????o de tais contaminantes. As rizobact??rias, que possuem alto poder de produ????o de biossurfactantes, tornam-se uma alternativa vi??vel por serem microrganismos n??o patog??nicos e, assim, seguros a plantas e animais. Diante disso, considerando que os solos de v??rzea s??o regi??es sujeitas ?? contamina????o por derivados de petr??leo e considerando que as rizobact??rias s??o esp??cies que est??o presentes nesse tipo de solo e podem auxiliar no processo de degrada????o, o presente estudo prop??s-se a determinar o potencial individual de biodegrada????o de HPA de cinco isolados de rizobact??rias e do cons??rcio das cinco esp??cies em amostras de solo de v??rzea da Amaz??nia contaminado com ??leo diesel. Para isso, foi realizado um experimento utilizando suspens??o microbiana com 1 ?? 107 UFC.mL-1 de cada esp??cie e do cons??rcio entre elas, em 500 g de solo autoclavado e ??leo diesel como fonte de carbono. Al??m disso, foram feitas duas amostras controle: (A) 500 g de solo autoclavado e ??leo diesel e (B) 500 g de solo natural e ??leo diesel. Ap??s a montagem do experimento foram realizadas coletas para determina????o dos HPA nos tempos 0, 2, 5, 10, 15 e 21 dias. Ap??s os 21 dias do experimento, as bact??rias INPA R574 e INPA R598 degradaram 57,37% e 41,53%, respectivamente, do ??HPA, enquanto as demais apresentaram aumento na concentra????o do ??HPA. Ap??s 2 dias, onde observaram-se as melhores taxas de degrada????o, a esp??cie INPA R574 foi o microrganismo que mais se destacou. Em se tratando do ??HPA, essa bact??ria degradou 62,15%, enquanto que, de maneira individual, reduziu as concentra????es de acenafteno, fenantreno e benzo(a)pireno em 86,47%, 44,65% e 79,72%, respectivamente. No mesmo tempo, o cons??rcio apresentou taxa de 64,36%, valor superior, no entanto bem pr??ximo ?? taxa individual da esp??cie INPA R574. O microrganismo INPA R548 foi o que n??o contribuiu de maneira significativa para a degrada????o de nenhum dos contaminantes estudados, bem como do ??HPA. A amostra controle A apresentou taxas de degrada????o relevantes, sugerindo que os nutrientes adicionados ao controle favoreceram o crescimento de bact??rias nativas do solo que foram capazes de degradar os HPA do diesel adicionado ??s amostras.
Databáze: OpenAIRE
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