Degradation Of Pyrene In Soil Research Articles

Incorporation of N-doped biochar into submicron zero-valent iron for efficient peroxydisulfate activation in soil remediation: Performance and mechanism

The development of strategic methods to enhance the catalytic reactivity and electron efficiency of biochar-modified zero-valent iron (BC-ZVI) via mechanochemistry is highly important and desirable for the use of peroxydisulfate-based advanced oxidation processes (PDS-AOPs) in soil remediation. Herein, novel amphiphilic ball-milled N-doped biochar-ZVI composites (NBC-ZVIbm) were fabricated to activate PDS for efficient pyrene degradation in soil. The N-doped site- and alloying heterojunction-induced surface charge redistribution, directional electron transfer, and amphiphilicity of NBC-ZVIbm were verified, all of which improved the interactions among NBC-ZVIbm, PDS and pyrene. Specifically, NBC incorporation optimized PDS oxidation and pyrene adsorption on NBC-ZVIbm, forming a reaction center that efficiently accelerated the reaction. As a result, 95.5 % of 98.3 mg/kg pyrene in soil was degraded by NBC-ZVIbm/PDS within 7 d, which was 2.3 and 1.5 times greater than that of ball-milled ZVI and BC-ZVIbm, respectively; additionally, the electron efficiency of this process increased to 85.2 %. Characterization of the reaction process suggested that NBC incorporation induced directional electron transfer from ZVI to NBC for PDS activation and SO4•- generation. Subsequently, the amphiphilicity of NBC-ZVIbm promoted soil phase-pyrene desorption and migration, thereby increasing pyrene degradation. This NBC-incorporation method provides a strategy for constructing highly efficient ZVI-based catalysts for the use of PDS-AOPs in soil remediation.

Degradation of pyrene in contaminated water and soil by Fe2+-activated persulfate oxidation: Performance, kinetics, and background electrolytes (Cl-, HCO3- and humic acid) effects

SO4−-based oxidation technologies have been considered as key solution in polycyclic aromatic hydrocarbons (PAHs) degradation. This study constructed Fe2+-activated persulfate oxidation to degrade pyrene in water and soil by using batch and column experiments. Pyrene degradation kinetic in polluted water and effects of soil background electrolytes (Cl−, HCO3− and humic acid) on pyrene degradation were both investigated. The variation of soil properties during pyrene degradation in soil was evaluated. Polluted water remediation results showed that approximately 93.2 % of pyrene was degraded by 65 mM of persulfate with Fe2+/persulfate molar ratio of 0.25. In soil, 88.5 % of pyrene was degraded under the same persulfate concentration and Fe2+/persulfate molar ratio, and there was a slight decrease of soil pH (from 6.7 to 5.4). Cl−, HCO3− and humic acid in soil brought an adverse effect to pyrene degradation through scavenging SO4−. Column study of soil remediation proved the superiority of Fe2+ in activating persulfate, whose application in soil remediation can finally reduce soil pollution and simultaneously avoid the excessive soil acidification in in-situ remediation. In addition, by evaluating the soil organic matter and total organic carbon during the remediation process, it was found that the soil properties have been improved. Therefore, Fe2+-activated persulfate oxidation would be a feasible way to remediate pyrene polluted water/soil.

Rhizobacterial community of Jatropha curcas associated with pyrene biodegradation by consortium of PAH-degrading bacteria

A bacterial consortium consisting five efficient polyaromatic hydrocarbon (PAH) degraders (Pseudomonas aeruginosa PDB1, Pseudomonas fragi DBC, Klebsiella pneumoniae AWD5, Alcaligenes faecalis BDB4 and Acinetobacter sp. PDB4) was bioaugmented in pyrene contaminated soil through Jatropha curcas rhizosphere, to understand its effect on changes in bacterial community structure during the process of rhizosphere mediated biodegradation of pyrene. This consortium was highly effective in rhizosphere mediated remediation, as 97.2% of pyrene was degraded within 60 days. The better degradation of pyrene in soil was correlated with the changes in bacterial community structure in rhizosphere of J. curcas, for different trials. The Proteobacteria remained the most abundant group among different treatments, but its abundance was 30.7% higher in the rhizosphere of plants growing in pyrene contaminated soil augmented with consortium. Sphingomonas, Sphingobium, Achromobacter, Ralstonia, Pseudoxanthomonas, Devosia, Cupriavidus, and the members of Sphingomonadeceae, Rhizobiaceae, Xanthomonadeceae, were dominant within Proteobacteria, where pyrene degradation was maximum. There was strong correlation between abundances of group of bacteria which were being affected with pyrene contamination or consortium treatment, and this effect was spread over for a group of bacteria, whose abundances were interdependent. Consequently, the treatment of PAH degrading consortium restored and recruited group of bacteria, which were otherwise depleted in presence of pyrene. Therefore, the application of consortium not only facilitated the degradation of pyrene, but also resulted in modulation of the bacterial community in the process of rhizosphere mediated biodegradation of pyrene in soil.

Additive Effect of Piriformospora Indica Fungus and Rhodococcus Erythropolis Bacteria on Bio-Remediation of Pyrene in a Pb-Polluted Soil Treated With Tire Rubber Ash

Background and Purpose: This research was conducted to evaluate the effect of Piriformospora indica fungus (P. indica) and Rhodococcus erythropolis (R. erythropolis) bacteria on bio-remediation of pyrene in a Pb-polluted soil that was treated with tire rubber ash.
 Materials and Methods: Treatment consisted of applying tire rubber ash at the rates of 0 and 300 mg/kg soil, soil polluted with pyrene at the amount of 0 and 100 mg/kg soil, soil pollution with Pb (0, 400 and 800 mg/kg soil), and finally plant inoculated with P. indica fungus and R. erythropolis bacteria, and the plant used in this experiment was canola. After 60 days, plants were harvested and plant Pb and Zn concentration was measured using atomic absorption spectroscopy (AAS). The pyrene concentration in the soil samples were extracted by soxhlet using n-hexane and a 1:1 (v/v) dichloromethane during 24 h and measured according to the Besalatpour et al. (2011). The basal soil microbial respiration was measured as evolved CO2.
 Results: A significant increase (P=0.05) by 15.1% was observed in pyrene degradation in soil when plant inoculated with P. indica and R. erythropolis. However, soil pollution with Pb significantly decreased the pyrene degradation in the soil. At the same time, adding tire rubber ash to the soil significantly increased the plant biomass and pyrene degradation.
 Conclusion: Plant inoculation with P. indica and R. erythropolis had an additive effect on pyrene degrading (bio-remediation) in soil that is an important factor in environmental studies. However, soil pollution with heavy metals showed an adverse effect on it.

Analyses of intermediate products during degradation of pyrene in soil by hemoglobin-catalyzed reaction

Hemoglobin (Hb) is a member of heme-protein that can perform catalytic non-specific chain reaction in the presence of hydrogen peroxide (H2O2). Catalytic ability of Hb to degrade pyrene was demonstrated using soil contaminated with 14C pyrene and 10 mg pyrene /kg soil. The composition of soil was similar to previously used soil except that it had lower organic carbon content. Bench scale laboratory tests were conducted in the presence of buffer only, H2O2 only, or Hb with H2O2 for 24 h. After 24 h reaction, 0.1 and 1.3% of 14C pyrene in contaminated soil were mineralized with H2O2 only or Hb plus H2O2. No mineralization to 14CO2 was detected with buffer only. Approximately 12.2% of pyrene was degraded in the presence of H2O2 only while 44.0% of pyrene was degraded in the presence of Hb plus H2O2 during 24 h of catalytic reaction. When degradation intermediate products were examined, two chemicals were observed in the presence of H2O2 only while 25 chemicals were found in the presence of Hb plus H2O2. While most degradation products were simple hydrocarbons, four of the 27 chemicals had aromatic rings. However, none of these four chemicals was structurally related to pyrene. These results suggest that Hb catalytic system could be used to treat pyrene-contaminated soil as an efficient and speedy remediation technology. In addition, intermediate products generated by this system are not greatly affected by composition change in soil organic matter content.

The role of artificial root exudate components in facilitating the degradation of pyrene in soil

Root exudates play an important role in the phytoremediation of soils contaminated by organic pollutants, but how root exudate components affect the remediation process is not well understood. In this study, we explored the effects and mechanisms of the major root exudates, including glucose, organic acids, and serine, in the rhizoremediation of pyrene-contaminated soil. The results showed that glucose increased the degradation of pyrene (54.3 ± 1.7%) most significantly compared to the organic acids (45.5 ± 2.5%) and serine (43.2 ± 0.1%). Glucose could significantly facilitate the removal of pyrene in soil through promoting dehydrogenase activity indicated by a positive correlation between the removal efficiency of pyrene and the soil dehydrogenase activity (p < 0.01). Furthermore, root exudates were able to change soil microbial community, particularly the bacterial taxonomic composition, thereby affecting the biodegradation of pyrene. Glucose could alter soil microbial community and enhance the amount of Mycobacterium markedly, which is dominant in the degradation of pyrene. These findings provide insights into the mechanisms by which root exudates enhance the degradation of organic contaminants and advance our understanding of the micro-processes involved in rhizoremediation.

Degradation of pyrene in soil and &lt;i&gt;in vitro&lt;/i&gt; by a &lt;i&gt;Bacillus lentus&lt;/i&gt; strain isolated from an asphalt plant soil site in Lagos, Nigeria

A bacterium isolated from an asphalt plant soil and identified as a strain of Bacillus lentus was tested in vitro and in sterilized and native soils for ability to survive and sustain pyrene degradation over a period of 63 days. The exponential growth rate in vitro was 0.049 d -1 and the doubling time 2.65 d. In the control flask without pyrene, organism density remained virtually constant. In sterilized soil seeded with Bacillus lentus LP32 pyrene concentration declined from 335.0 mg/kg to 8.56 mg/kg at the rate of 10.88 mg/kg/day and half-life of 5.67 days. Similarly, in the native soil seeded with organism there was a decline from 305.2 mg/kg to 8.58 mg/kg in 30 days at the rate of 9.89 mg/kg/day and half-life 5.82. The percentage pyrene degraded in both sterilized and native soils were similar, at 97.45% and 97.19% respectively. This study demonstrated the potential of Bacillus lentus LP32 to serve as seed for enhanced bioremediation of pyrene polluted soil. Keywords: Bacillus , Biodegradation, Bioremediation, Gas chromatography, Pyrene

Anthracene and benzo(a)pyrene degradation in soil is favoured by compost amendment: Perspectives for a bioremediation approach

In order to validate the use of compost in soil PAH bioremediation, the degradation of anthracene and benzo(a)pyrene was monitored in soils artificially contaminated and incubated in mesocosms under controlled conditions. The dynamics observed in compost amended soil were compared to those observed in soil added with a fungal consortium and untreated soil. At the same time, three microbial enzyme activities usually involved in PAH degradation (laccase, o-diphenol oxidase and peroxidase activities) were monitored.Both PAHs decreased along the time in the three mesocosms, with anthracene, with lower molecular weight, degrading with a higher rate and reaching lower residual values than benzo(a)pyrene. Although at the end of incubation, the residual values of investigated PAHs are similar in the three mesocosm types, PAH dynamics showed a higher degradation rate in the early stage in mesocosms added with the fungal mycelium and amended with compost. Among the three enzyme activities, only peroxidase showed higher values in treated than untreated mesocosms. Considering the ameliorating effects of compost on degraded soils, its use can be suggested in PAH bioremediation.

Kinetic analysis of soil contained pyrene oxidation by a pulsed discharge plasma process**Supported by National Natural Science Foundation of China (No. 21207052).

A pulsed discharge plasma (PDP) reactor with net anode and net cathode was established for investigating the pyrene degradation in soil under different pulse peak voltage, air flow rate, pyrene content in soil, initial pH value and initial water content of the soil. Pyrene oxidation within the 60 min discharge time was fitting according to the pseudo-first order equation and the corresponding reaction kinetics constants (k values) were calculated. The obtained results show that pyrene oxidation under all the different reaction conditions obeyed the pseudo-first order equation well. Higher pulsed peak voltage and appropriate air flow rate were in favor of the increase of reaction rate of pyrene oxidation. A higher k value could be achieved in the lower initial pyrene content (the value was 100 mg kg−1). The k value of pyrene oxidation in the case of pH = 4 was 11.2 times higher than the value obtained under the condition of pH = 9, while the initial water content of the soil also has a large effect on the oxidation rate of pyrene due to the effect of PDP.

Effects of Tween 80 on Degradation of Pyrene in Soils Growing &lt;em&gt;Sorghum sudanese&lt;/em&gt;

Phytoremediation is becoming a cost-effective technology for the in-situ clean up of sites polluted with Hydrophobic Organic Contaminants (HOCs). The major factors limiting phytoremediation are the mass transfer, rate of plant uptake and microbial biodegradation of HOCs. To evaluate the potential of surfactants to enhance phytoremediation for HOC-contaminated sites, the efficacy of Sudan grass ( Sorghum sudanense ), at the absence or presence of polyoxyethylene sorbitan monooleate (Tween 80), on the degradation of pyrene in soils were investigated and mechanisms of Surfactant-Enhanced Phytoremediation (SEPR) were discussed. Results showed that the presence of Tween 80 enhanced dissipation of pyrene at initial contents ranging from 20.24 to 321.42 mg/kg. During the 70-d SEPR-experiments, about 801.84~539.99‰ of pyrene was removed from planted soils, only 242.28~122.79‰ degradation of pyrene occurred in unplanted ones. With the presence of Tween 80, the dissipation ratios of pyrene in planted ones were increased up to 863.94~609.63‰, which was 77.27~129.14‰ higher than those in corresponding soils without surfactant. Among all possible pathways, contribution of plant-microbial interactions on dissipation of pyrene was the most significant, either at the presence (456.73‰) or absence (515.58‰) of Tween 80, were the primary means of contaminant degradation. Results suggested SEPR may be a feasible way for reinforcing removal of HOCs in contaminated sites.

Mineralization of pyrene induced by interaction between Ochrobactrum sp. PW and ryegrass in spiked soil

This study was conducted to investigate the capability of pyrene-degrading bacterium Ochrobactrum sp. PW and ryegrass (Lolium multiflorum) grown alone and in combination on the degradation of pyrene in soil. After 60 days of ryegrass growth, plant biomass, pyrene-degrading microbial mass, soil enzyme activity (catalase activity and polyphenol oxidase activity) and residual concentration of pyrene in soils were determined. Higher dissipation rates were observed in PW inoculation treatments: ryegrass+PW rhizosphere soil (RP-r) and ryegrass+PW non-rhizosphere soil (RP-nr), than planting of ryegrass alone, rhizosphere (R-r) or non-rhizosphere (R-nr). The inoculation with PW significantly (p<0.05) increased the dry weight of ryegrass root and shoot, nearly 2.8 and 3.3 times higher than ryegrass treatment. The pyrene-degrading microbial mass indicated that a much larger mass of bacteria, actinobacteria were present in RP treatment. The catalase activity in all different treatments were significantly (p<0.05) higher than in with treatment R-nr, and the polyphenol oxidase activity was also significantly (p<0.05) increased by inoculation with PW, leading to enhanced mineralization of pyrene from soil. Our results suggest that adding of PAHs-degrading bacteria to soil can enhance remediation of PAHs contaminated soil, while improving plant growth.

Effects of Polyoxyethylene Sorbitan Monooleate on Degradation of Pyrene in Soils Growing Sorghum Sudanese

Phytoremediation is becoming a cost-effective technology for the in-situ clean up of sites polluted with Hydrophobic Organic Contaminants (HOCs). The major factors limiting phytoremediation are the mass transfer, rate of plant uptake and microbial biodegradation of HOCs. To evaluate the potential of surfactants to enhance phytoremediation for HOC-contaminated sites, the efficacy of Sudan grass, at the absence or presence of polyoxyethylene sorbitan monooleate (Tween 80), on the degradation of pyrene in soils were investigated and mechanisms of Surfactant-Enhanced Phytoremediation (SEPR) were discussed. Results showed that the presence of Tween 80 enhanced dissipation of pyrene at initial contents ranging from 20.24 to 321.42 mg/kg. During the 70-d SEPR-experiments, about 801.84~539.99‰ of pyrene was removed from planted soils, only 242.28~122.79‰ degradation of pyrene occurred in unplanted ones. With the presence of Tween 80, the dissipation ratios of pyrene in planted ones were increased up to 863.94~609.63‰, which was 77.27~129.14‰ higher than those in corresponding soils without surfactant. Among all possible pathways, contribution of plant-microbial interactions on dissipation of pyrene was the most significant, either at the presence (456.73‰) or absence (515.58‰) of Tween 80, were the primary means of contaminant degradation. Results suggested SEPR may be a feasible way for reinforcing removal of HOCs in contaminated sites.

Effect of chemical parameters on pyrene degradation in soil in a pulsed discharge plasma system

Abstract Degradation of pyrene in soil in a net-to-net pulsed discharge plasma (PDP) system was reviewed. Effect of main chemical parameters, including air flow rate, pyrene concentration, initial pH and soil moisture content on pyrene degradation was examined. The obtained results show that 87.9% of pyrene could be removed under the condition of 60 min reaction; increasing of air flow rate within 1 L min−1 was favorable for degradation; pyrene removal was decreased with the increase of initial pyrene concentration; oxidation of pyrene was more evident in acidic soil; enhancement of soil moisture content has no benefit on pyrene degradation.

Effects of Biostimulation and Bioaugmentation on The Degradation of Pyrene in Soil

Petroleum based products have been widely used as a source of energy for centuries. One of the main petroleum hydrocarbons of concern is Polycyclic Aromatic Hydrocarbon (PAHs) which include pyrene. Pyrene is a four ring PAHs commonly found in soils contaminated with petroleum based products. The effectiveness of the addition of nutrient (biostimulation) and Mycobacterium sp. (bioaugmentation) on biodegradation of pyrene in soil was evaluated. The addition of nutrients (biosimulation) and microorganisms (bioaugmentation) increased the number of viable cells over the control during the bioremediation process. The cell number increased by 40, 70, 59 and 132 fold for the control, biosimulation, bioaugmentation and combined bioaugmentation, respectively. A lag period of 0.5 d and a specific growth rate of 0.896 d-1 were observed with the combined biosimulation-bioaumentation treatment. The temperature results showed that the temperature of the combined biostimulation-bioaugmentation reached 41°C after two days of treatment while the maximum temperature of the control, biostimulation and bioaugmentation were within the range of 28-32°C. The moisture content decreased for all treatments reaching 45-57% but remained within the optimum range of 40-60% for bioremediation process. This was due to the fact that the moisture lost in the exhaust gas was not compensated by the water produced as a by-product of the organic matter degradation. The level of pyrene degradation was indicated by the decline in O2 concentration and the increase in CO2 concentration in the exhaust gas. The control, biostimulation and bioaugmentation treatments showed similar patterns of decreasing O2 and increasing CO2. However, the combined biostimulation-bioaugmentation treatment recorded a declining trend in O2 concentration and increasing trend in CO2 concentration in the exhaust gas at the beginning of experiment (first 7 days) followed by increasing trend in O2 concentration and decreasing trend in CO2concentration in the next 8 days of the experiment. The highest pyrene reduction in percentage (84.29%) was obtained through the combined bioaugmentation-biostimulation process followed by bioaugmentation (57.86%), biostimulation (50%) and control (37%) processes. Different pyrene degradation rates were observed during the various phases of microbial growth (lag, exponential and stationary) of combined bioaugmentation-biostimulation treatment.

Biodegrading of pyrene by a newly isolated Pseudomonas putida PL2

Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic compounds derived from natural sources and anthropogenic processes, which have been recommended as priority pollutants. Degradation of PAHs in the environment is becoming more necessary and urgent. In the current study, strain PL2, which is capable of growing aerobically on pyrene (PYR) as the sole carbon source, was isolated from hydrocarbons-contaminated soil and then identified as Pseudomonas putida by morphological and physiological characteristics as well as 16S rDNA sequence. The strain PL2 was able to degrade 50.0% of the pyrene at 28°C within 6 days in the presence of 50 mg/L pyrene, while the strain PL2 degraded 50.0% of the pyrene within 2 days when a solution of 50 mg/L pyrene and 50 mg/L phenanthrene was used. In addition, phenanthrene was shown to increase the biodegradation efficiency of pyrene by the strain PL2. The order of degradation by the strain PL2 was pH 6.0 > pH 7.0 > pH 5.0 > pH 8.0. The degradation rate of PYR in the soil by the strain PL2 reached 70.0% at the 10th day. The dynamics of PYR degradation in soil by PL2 was fit to the first order model and the strain PL2 was shown to efficiently degrade PYR in soil. The current study showed that P. putida PL2 was a novel bacterium that could degrade pyrene and holds great promise for use in PAHs bioremediation in soil.

Degradation of pyrene in soils by extracellular polymeric substances (EPS) extracted from liquid cultures

The extracellular polymeric substances (EPS) isolated from Zoogloea sp. and Aspergillus niger ( A. niger) were employed in studies of degradation of pyrene in contaminated soils. The results of the present study showed that pyrene could be degraded in the presence of any one EPS, and the reduction of pyrene increased as the initial concentration of EPS increased. The best degradation was obtained in the presence of Zoogloea sp. EPS 5332.34 mg kg −1 + A. niger EPS 6512.17 mg kg −1, and more than 80% of pyrene was degraded after 35 days, meanwhile, the speedy degraded time was greatly reduced to 14 days from the 21 days required for other EPS combination. To understand the underlying principles of EPS depleting pyrene, the potential factors resulted in this phenomenon were discussed in the latter part, which could provide new insight into the function of EPS in bioremediation of polycyclic aromatic hydrocarbons (PAHs) contaminated soils.

Dynamic changes in functional gene copy numbers and microbial communities during degradation of pyrene in soils

This study investigates the dynamics of pyrene degradation rates, microbial communities, and functional gene copy numbers during the incubation of pyrene-spiked soils. Spiking pyrene to the soil was found to have negligible effects on the bacterial community present. Our results demonstrated that there was a significant difference in nidA gene copy numbers between sampling dates in QZ soil. Mycobacterium 16S rDNA clone libraries showed that more than 90% mycobacteria detected were closely related to fast-growing PAH-degrading Mycobacterium in pyrene-spiked soil, while other sequences related to slow-growing Mycobacterium were only detected in the control soil. It is suggested that nidA gene copy number and fast-growing PAH-degrading Mycobacterium could be used as indicators to predict pyrene contamination and its degradation activity in soils.

Pyrene degradation and detoxification in soil by a consortium of basidiomycetes isolated from compost: Role of laccases and peroxidases

A consortium of three basidiomycetes isolated from compost was investigated for pyrene degradation in soil microcosms. Pyrene concentration, glucose and ammonium evolution, moisture content, ligninolytic enzyme activities and phytotoxicity (germination index) on Lepidium sativum L. seeds were monitored. The fungal consortium grown on straw was found able to efficiently colonize soil and remove about 56 out of 100 mg kg −1 of soil dry weight of pyrene in 28 days; in the meantime the germination index increased indicating a reduction of phytotoxicity. A glucose supply after 2 weeks was found useful to ensure fungal growth and activity; maintenance of moisture content below 70% allowed a good aeration of the system and improved degradation rates. Enzymatic assays showed that laccase and manganese independent peroxidase activity could have played a role in the degradation process.

Application of Phytoremediation on Soil Contaminated by Pyrene

The purpose of this study was to treat soils contaminated by pyrene through phytoremediation. The plant species selected were Phragmites communis Trin., Typha orientalis Presl, Vetiveria zizanioides, Rohdea japonica (Thunb.) Roth et Kunth, Cyperus malaccensis. Lam. subsp. monophyllus (Vahl) T. Koyama, Bolboschoenus planiculmis (F. Schmidt) T. Koyama, and Bidens pilosa. The degradation of pyrene in soils was analyzed. The experimental results of this study indicated that the degradation efficiencies of pyrene from soils by V. zizanioides, R. japonica, and T. orientalis were 86, 84, and 77%, respectively, after 14 weeks. These values of degradation percentages were higher than those measured in the unplanted control experiment, which was found equal to 66%. In addition, the pyrene degradation efficiencies in summer were found to be higher than those in winter. The degradation percentages of pyrene sterilized soil with and without T. orientalis were found to be 59 and 55%, respectively. These values were fou...

Degradation of Pyrene in Soils by Free and Immobilized Yeasts, Candida tropicals

The aim of this research was to ascertain the efficacy of immobilized yeasts for the degradation of pyrene in soil. Pyrene degradation by individual yeasts and their mixtures was clearly enhanced when the yeasts were immobilized with chemical and physical entrapments, and cross-shaped beads from physical entrapment were more promising than spherical beads from chemical entrapment. Immobilized yeast mixture Candida tropicals Y 219 + Y 220 showed the best degradation of pyrene, exhibiting collaboration in pyrene removal. Scanning electron micrographs demonstrated good macroporous structure for mass transfer of substrates and immobilized cell growth.