Phylogenetic analysis of long-chain hydrocarbon-degrading bacteria and evaluation of their hydrocarbon-degradation by the 2,6-DCPIP assay

Abstract

Thirty-six bacteria that degraded long-chain hydrocarbons were isolated from natural environments using long-chain hydrocarbons (waste car engine oil, base oil or the c-alkane fraction of base oil) as the sole carbon and energy source. A phylogenetic tree of the isolates constructed using their 16S rDNA sequences revealed that the isolates were divided into six genera plus one family (Acinetobacter, Rhodococcus, Gordonia, Pseudomonas, Ralstonia, Bacillus and Alcaligenaceae, respectively). Furthermore, most of the isolates (27 of 36) were classified into the genera Acinetobacter, Rhodococcus or Gordonia. The hydrocarbon-degradation similarity in each strain was confirmed by the 2,6-dichlorophenol indophenol (2,6-DCPIP) assay. Isolates belonging to the genus Acinetobacter degraded long-chain normal alkanes (n-alkanes) but did not degrade short-chain n-alkanes or cyclic alkanes (c-alkanes), while isolates belonging to the genera Rhodococcus and Gordonia degraded both long-chain n-alkanes and c-alkanes.

Estudos de biodegradação de óleo diesel por consórcio microbiano coletado em Porto Velho - RO, amazônia

“…Assim, a presença de aceptores de elétrons, como o 2,6-diclorofenol indofenol, no meio de cultura pode ser utilizada para averiguar a presença de micro-organismos que usam hidrocarbonetos como substrato, pela observação da mudança de cor do 2,6-diclorofenol indofenol de azul (oxidado) para incolor (reduzido). 15 Os ensaios realizados com o consórcio microbiano apresentaram resultados positivos, obtidos a partir da observação visual da completa descoloração do meio após 96 h. Em seguida, foi investigada a possível produção de biossurfactantes pelo consórcio microbiano, já que hidrocarbonetos apresentam baixa solubilidade em água e a presença de biossurfactantes auxilia o processo de biodegradação pelo aumento da disponibilidade dos hidrocarbonetos aos microorganismos. 23 O surfactante produzido pelo consórcio apresentou um índice de emulsificação de 53%, quando o diesel foi utilizado como agente apolar.…”

“…O experimento foi baseado na metodologia descrita por Kubota et al 15 e feito em tubos de ensaio contendo 7,5 mL de meio de cultivo BH (Bushnell-Haas) com 7,5 µg/mL do indicador redox 2,6-diclorofenol indofenol, 50 µL de diesel e 125 µL de inóculo. Os tubos de ensaio foram mantidos a 30 °C em shaker rotatório e observados com frequência até o desaparecimento da coloração azul.…”

Isolation and identification of bacterial consortia responsible for degrading oil spills from the coastal area of Yanbu, Saudi Arabia

“…[17] The polymerase chain reaction (PCR) programme was set at 30 cycles and the amplification was carried out as follows: 92 C for 2 min, 42 C for 30 s, 72 C for 4 min and 4 C incubation at the end of the last cycle. [18,19] The amplified fragments were sequenced by Macrogen (Seoul, South Korea) and a phylogenetic tree was constructed using MEGA version 4. [20,21] …”

Sequential Remediation Processes for Effective Removal of Oil from Contaminated Soils

“…A gram of soil may contain up to a billion bacteria, a million algae, 100 thousand protozoa and 10 km of fungi hyphae (Trevors, 2010). Table 1 shows a list of known hydrocarbons degrading microorganisms (Beilen et al, 2003;Wentzel et al, 2007;Kubota et al, 2008;Prince1 et al, 2003;Capotorti et al, 2004).…”

“…Canada produces about 1.4×106 tons annually which are exported to Japan, USA, Holland, Germany, England and Saudi Arabia (Mitsch and Gosselink, 2007). (Beilen et al, 2003;Wentzel et al, 2007;Kubota et al, 2008;Prince1 et al, 2003;Capotorti et al, 2004 Objectives: The object of this study was to develop a system for the remediation of soil contaminated with petroleum hydrocarbons. The specific objectives were: (a) to develop an effective soil washing process for the removal of the hydrocarbons from the contaminated soil, (b) to develop an efficient water decontamination process using peat moss and (c) to evaluate the effectiveness of bioremediation in converting the oil in peat moss into carbon dioxide and water.…”