Improved extraction method to evaluate the degradation of selected PAHs by marine fungi grown in fermentative medium

Abstract

O estudo propõe um método otimizado para avaliar a degradação de hidrocarbonetos policíclicos aromáticos (HPAs) por fungos filamentosos. A adsorção dos HPAs pelo micélio requer o emprego de uma extração exaustiva, normalmente realizada através da combinação de diferentes técnicas aplicadas, separadamente, ao meio líquido e ao micélio. Este trabalho sugere uma simplificação da etapa de extração, reduzindo o tempo de análise e a manipulação da amostra e garantindo a precisão e a exatidão do método. Os HPAs selecionados, pireno e benzo [a] An improved method to evaluate the degradation of polycyclic aromatic hydrocarbons (PAHs) for filamentous fungi is hereby proposed. The PAH adsorption through fungal mycelia implies the use of an exhaustive extraction, which is usually performed through a combination of different techniques applied separately to the liquid medium and to the mycelia. This work proposes a simplified extraction procedure with reduced analysis time and sample manipulation, thereby guaranteeing its precision and accuracy. The selected PAHs, pyrene and benzo[a]pyrene, were quantified by gas chromatography using a mass selective detector operating in single ion monitoring mode. The method was validated presenting accuracy within the scope of this study and it was used for evaluating the potential of PAHs degradation by thirteen fungi derived from marine environment. This study selected the fungus Aspergillus sclerotiorum CBMAI 849 for being able to degrade 85% of pyrene and 61% of benzo[a]pyrene after 4 and 8 days, respectively, and the fungus Mucor racemosus CBMAI 847 for being able to degrade 44% of benzo[a]pyrene after 8 days.

The culturable mycobiota of a Mediterranean marine site after an oil spill: isolation, identification and potential application in bioremediation

“…Actually, fungi have been recently reported for their capability to use PAHs as benzo [a]pyrene (Passarini et al, 2011) and to produce biosurfactants (Kirianet al, 2009).…”

Filamentous Fungi Isolates of Contaminated Sediment in the Amazon Region with the Potential for Benzo(a)pyrene Degradation

“…The biodegradation assays were based on the method proposed by Passarini et al (2011a) and performed according to the cultivation, inoculation, and incubation methodology described in item 2.4. After 72 h of incubation, 125 mL Erlenmeyer flasks containing 30 mL of MEB2 were supplemented with 1 mg of BaP (Assay I) and 2 mg of BaP (Assay II), diluted in 0.5 mL dimethylsulfoxide and incubated for 14 days.…”

“…Several species of fungi with abilities to degrade PAH were reported in the literature, including ligninolytic and non-ligninolytic strains. Among the non-ligninolytic fungi, Aspergillus ochraceus, Cunninghamella elegans, and Cunninghamella echinulata were mentioned as able to degrade phenanthrene, fluoranthene, pyrene, chrysene, and benzo(a)pyrene (Cerniglia 1992;Muncnerová and Augustin 1994), Aspergillus sclerotiorum and Mucor r ac e m o s u s as a bl e t o d eg r ad e p y r e ne a n d benzo(a)pyrene (Ravelet et al 2000;Passarini et al 2011a), and Penicillium sp. and Trichoderma harzianum as efficient in benzo(a)pyrene degradation (Machín-Ramírez et al 2010).…”

Fungal biodegradation of anthracene-polluted cork: A comparative study

“…The degradation studies with high molecular weight PAHs for non-ligninolytic fungi revealed that Zygomycetes, and in particular M. racemosus, appeared as one of the most efficient taxonomic groups to degrade these types of PAHs (4-7 rings) such as pyrene and benzo[a]pyrene [11,40] . P. simplicissimum and M. racemosus have also demonstrated the ability to remove pyrene in a liquid synthetic medium after 2 days (2.4 and 3.26 mg g -1 of pyrene, respectively) [19,30] .…”