Bioremediation

Biosorption is a physico-chemical and metabolically-independent process based on a variety of mechanisms including absorption, adsorption, ion exchange, surface complexation and precipitation. Biosorption processes are highly important in the environment and conventional biotreatment processes. As a branch of biotechnology, biosorption has been aimed at the removal or recovery of organic and inorganic substances from solution by biological material which can include living or dead microorganisms and their components, seaweeds, plant materials, industrial and agricultural wastes and natural residues. For decades biosorption has been heralded as a promising cost-effective clean-up biotechnology. Despite significant progress in our understanding of this complex phenomenon and a dramatic increase in publications in this research area, commercialization of biosorption technologies has been limited so far. This article summarizes existing knowledge on various aspects of the fundamentals and applications of biosorption and critically reviews the obstacles to commercial success and future perspectives.

Paraffin wax produced from crude oil consists primarily of long chain, saturated hydrocarbons (linear alkanes/ n-paraffins) with carbon chain lengths of C18 to C75+, having individual melting points from 40 to 70°C. This wax material is referred to as " macrocrystalline wax. " Naphthenic hydrocarbons (C18 to C36) also deposit wax, which is referred to as " microcrystalline wax. " Macrocrystalline waxes lead to paraffin problems in production and transport operations; microcrystalline waxes contribute the most to tank-bottom sludges.[1] The n-heptane structure is an example of a " normal " paraffin; 2-methyloctane is an " iso " paraffin and n-butylcyclopentane is a naphthene. These specific n-paraffins and naphthenes are too small to crystallize as wax deposits The iso-paraffins of the 2-methyloctane type are more likely to be included in a wax deposit than the more highly branched alkanes. The solubility line of wax is hardly a function of pressure, so wax deposition is considered to be only temperature dependent. (Rønningsen, 2006) As the temperature of the crude drops below a critical level and/or as the low-molecular-weight hydrocarbons vaporize, the dissolved waxes begin to form insoluble crystals. The deposition process involves two distinct stages: nucleation and growth. Nucleation is the forming of paraffin clusters of a critical size (" nuclei ") that are stable in the hydrocarbon fluid. This insoluble wax itself tends to disperse in the crude. Nathan (1955) classified the carbonaceous fractions of paraffin deposits as: (1) soluble in cold acetone (generally the contained oil); (2) soluble in hot acetone (the soft wax portion); and (3)insoluble in acetone (hard wax). The hard wax material consists of straight chain material with molecular weights of 525 to 700 daltons. The proportions of each of these will vary from well to well, and even in a given well at different times. Burger et al. (1981) found that deposits in the trans-Alaska pipeline consisted of 14 to 17% solid (wax), 86 to 83% whole oil. Wright, (1951) remarked that the number of different compounds and types of waxes found in paraffin are dependent upon the character of the crude oil.

Abstract The capability of the microalgae Chlorella vulgaris (Cv) for biomass production and nutrients removal under different wastewater quality has been studied. Cv was cultivated in a standard medium ( Marine labs American society of microbiology-derived medium , MLA) blended with primary wastewater ( P WW ), secondary wastewater ( S WW ) and petroleum effluent ( P E ) in different volume ratios. Macro and micro nutrients were characterized in each solution, and the impact on the rate of biomass growth (specific growth rate, μ ) and removal efficiency (RE) determined for the bulk nutrients (total nitrogen TN and total phosphorus TP ) along with a range of macro- and micro-nutrients. P WW , S WW and P E media were found to provide an appropriate quantity and balance of nutrients to promote significantly more rapid algal growth than the standard medium MLA, with high nutrient RE achieved at the end of cultivation period. Over a 13-day period the highest biomass concentration X max of 1.6 g L −1 was attained for P WW with corresponding values of 1.2 d −1 , 80% and 100% for μ , and TN and TP RE respectively. μ decreased to 0.75 d −1 for a 75%:25% blend of P WW with MLA and to 0.54 d −1 on further decreasing the blend ratio to 25:75  P WW : MLA, with corresponding TN removal efficiencies of 85% and 76% respectively; 100% removal of TP was obtained throughout. There was a slight increase in X max , μ and TN removal of 1.16 g L −1 , 0.62 d −1 and 83% respectively for S WW . The lowest X max of 0.64 g L −1 in P E was recorded was associated with values of 0.31 d −1 , 79% and 100% for μ, and removal efficiencies of TN and TP respectively.

DDT [1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane] is a major environmental pollutant and economical methods to remove DDT from the environment are required. In this work we used seaweed (dried and ground) to enhance DDT transformation in waterlogged soils. Initial daily rates of DDT biodegradation increased in the following order relating to the percentage by weight of added seaweed to soil 0.5 > 1 > 0 > 3 > 5 > 13 (w/w). The actual percentages of DDT biodegradation occurring within 6 weeks were 80, 64, 60, 50, 40 and 34 respectively. During soil incubation DDD [1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane] was the major metabolite found with small amounts of DDE [1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane] produced. The maximum amount of 4,4 -dichlorobenzophenone (DBP) (2.5%) produced was found in soil amended with 0.5% (w/w) seaweed, indicating that further degradation of DDD occurred. High levels of dissolved organic carbon (DOC), between 309 and 509 mg kg −1 soil, were present in soil amended with 3-13% (w/w) seaweed immediately after seaweed addition. It is possible that the high levels of DOC in soils amended with larger amounts of seaweed significantly retarded DDT biodegradation, possibly due to binding of DDT to DOC and subsequently decreasing the bioavailability of DDT to soil microbes.

The two smallest islands of the Azores have received at the same year the title of Biosphere Reserve, from the UNESCO’s Man and the Biosphere Programme. The territorial object of this article is precisely one of those islands, Graciosa Island. On the one hand this was a way to reward its good interaction between Man and Nature until that year. But afterwards how was that relationship carried out? Are measures being taken in order to elevate the environmental quality? Does a better environment compromise the island’s economic growth and affect its inhabitants’ standard of living? This dissertation will try to answer these questions. Furthermore a detailed analysis will be done concerning two types of intervention at the landscape in Graciosa island, under a perspective in which it is intended to juggle the biophysical environment with some of the social and economical aspects of Graciosa Island.

In this work, a brewer’s yeast strain was used to remove heavy metals from a synthetic effluent. The solid–liquid separation process was carried out using the flocculation ability of the strain. The yeast strain was able to sediment in the presence of Cu2+, Ni2+, Zn2+, Cd2+ and Cr3+, which evidences that the flocculation can be used as a cheap and natural separation process for an enlarged range of industrial effluents. For a biomass concentration higher than 0.5 g/l, more than 95% of the cells were settled after 5 min; this fact shows that the auto-aggregation of yeast biomass is a rapid and efficient separation process. Cells inactivated at 45 °C maintain the sedimentation characteristics, while cells inactivated at 80 °C lose partially (40%) the flocculation.The passage of metal-loaded effluent through a series of sequential batches allowed, after the second batch, the reduction of the Ni2+concentration in solution for values below the legal limit of discharge of wastewater in natural waters (2 mg/l); this procedure corresponds to a removal of 91%. A subsequent batch had a marginal effect on Ni2+ removal (96%).Together, the results obtained suggest that the use of brewing flocculent biomass looks a promising alternative in the bioremediation of metal-loaded industrial effluents since the removal of the heavy metals and cell separation are simultaneously achieved.

Aims:  The presented study was aimed to reveal transcriptional regulation of genes involved in SDS degradation (sdsA and sdsB) in Pseudomonas sp. ATCC19151. In addition, the ability of Pseudomonas sp. ATCC19151 to degrade anionic surfactants present in commercial detergent and septic tank drain was analysed.Methods and Results:  Strain ATCC19151, at 30°C, degrades all SDS present in the liquid medium (up to 4% w/v of SDS) within 48 h. ATCC19151 grows in the presence up to 15% (v/v) ‘Fairy’ commercial detergent and mineralizes 35% of present anionic surfactants. Analysis of the sdsA (PsdsA) and divergent sdsB (PsdsB) gene promoter activities revealed that SdsB acts as a positive regulator of sdsA and sdsB transcription. PsdsA and PsdsB activities rose significantly in the presence of the SDS, indicating inducibility of sdsA and sdsB transcription. DNA-binding assay indicated that SdsB directly regulates the transcription of sdsA and sdsB genes. Strain ATCC19151 grew in a sterile septic tank drain and on commercial detergent as sole source of carbon.Conclusions:  SdsA enables Pseudomonas sp. ATCC19151 to utilize SDS as a sole carbon source. SdsB is positive transcriptional regulator of sdsA and sdsB genes.Significance and Impact of the Study:  Ability of ATCC19151 to degrade anionic surfactants makes Pseudomonas sp. ATCC19151 a good candidate for bioremediation.

Perchlorate (ClO 4 2 ) release into the environment has occurred primarily in association with its manufacture and use in solid rocket propellant. When released into groundwater, perchlorate can spread over large distances because it is highly soluble in water and adsorbs poorly to soil. Two proven techniques to remove perchlorate from drinking water are anaerobic biological reactors and ion exchange. In this review, we focus on the application of microbiological systems for degrading perchlorate. Some bacteria can use perchlorate as an electron acceptor while oxidizing a large range of substrates. Perchlorate-respiring bacteria (PRB) are widely distributed in the environment, and are enriched at perchlorate-contaminated sites. We review the pathways by which PRB degrade perchlorate, and the different biological treatment processes that have been developed to remove perchlorate from water sources. We also discuss the effects of alternate electron acceptors in the water, such as oxygen and nitrate, on perchlorate removal. Although many different biological treatment systems using PRB have so far only been proven at the bench scale, all pilot scale tests performed to date with a few of these systems have been successful. The success of these perchlorate bioreactor tests indicates that biological treatment is a suitable method for soil remediation and water treatment of perchlorate-contaminated water.

Palabras clave: biorremediación, toxicidad, bacterias, rutas catabólicas, mecanismos moleculares RESUMEN Los plaguicidas N-metilcarbamatos, son muy utilizados a nivel mundial para controlar insectos, ácaros, nemátodos, hongos y malezas en diferentes cultivos. Son altamente tóxicos para humanos y animales, persisten en el ambiente y tienen movilidad significativa en suelos. Una posible alternativa para mitigar los efectos provocados por estos plaguicidas, es la biorremediación, que puede ser mediada por microorganismos capaces de degradar moléculas tóxicas y altamente complejas a moléculas menos complejas, no tóxicas y que pueden ser utilizadas por otros organismos. En esta revisión, se pretende hacer un análisis detallado acerca de los microorganismos biorremediadores de plaguicidas N-metilcarbamatos, puesto que se ha encontrado una gran diversidad de especies con rutas catabólicas de degradación diferentes; además, se analizarán las enzimas carbamato hidrolasas, que actúan sobre un amplio rango de sustratos, bajo distintas condiciones y los diversos mecanismos moleculares (plásmidos y genes) involucrados en los procesos de biodegradación de plaguicidas. La información recopilada es útil para entender los mecanismos que han desarrollado los microorganismos para degradar los plaguicidas N-metilcarbamatos.

The study was aimed at determining the effects of industrial effluents on the soil environment of Challawa industrial area, Kano State Nigeria. Profile pit soils were sampled in the areas affected by industrial effluents and the adjacent control area. Sampled soils were carried to the laboratories for physical (sand, silt and clay) and chemical (pH, OC, AP, Ca, Mg, K, Na, N, ECEC) properties determinations. The result of the analysis showed that different horizons of the affected pits had less sand than what was obtained at the unaffected pit (average 615.78 and 670 respectively), Apart from pH, nitrogen, available phosphorus content of the soils that were lower at the horizons from the affected area of the industrial site(on the average, pH 6.45; N-0.20 g/kg; AP-3.97 mg/kg), all other chemical properties (exchangeable bases like Ca (1.15 cmol/kg), Mg (0.4 cmol/kg) and Na (0.23 cmol/kg) were lower at the horizons of the unaffected profile pits. Other physical and chemical properties of the soils collected like the pH, organic carbon, total nitrogen and available phosphorus, Ca, Mg, K and Na were low in some pits and in some pits had higher concentration at the affected area. The revelation from the analysis showed that the top and upper horizons of the soil at the industrial site has been seriously tampered with by industrial effluents and inhabitants should be advised to plant mostly shallow rooted crops and cultivate on land farther away from the effluent sludge.

Lecturers and tutors
Simona Rossetti, IRSA-CNR, Italy
Anna Barra Caracciolo, IRSA-CNR, Italy
Federico Aulenta, IRSA-CNR, Italy
Claudia Beimfohr, Vermicon, Germany
Philippe Corvini , University of Applied Sciences and Arts
Northwestern Switzerland, Switzerland
Paola Grenni, IRSA-CNR, Italy
Nicolas Kalogerakis, Technical University of Crete, Greece
Caterina Levantesi, IRSA-CNR, Italy
Mauro Majone, Sapienza University of Rome, Italy
Bruna Matturro, IRSA-CNR, Italy
Jochen Müller, UFZ, Germany
Maurizio Petruccioli, DIBAF, University of Tuscia, Italy
Valter Tandoi, IRSA-CNR, Italy
Paul Wilmes, University of Luxembourg, Luxembourg
Giulio Zanaroli, University of Bologna, Italy""

An innovative bioprocess method, Systematic Environmental Molecular Bioremediation Technology (SEMBT) that combines bioaugmentation and biostimulation with a molecular monitoring microarray biochip, was developed as an integrated bioremediation technology to treat S-and ...

Our study dealt with the phenol bioremediation potential of Earthworms which were collected from a vermicomposting unit in Vellore, Tamil Nadu and maintained under proper growth conditions. Different concentrations of phenol ranging from 10ppm to 50ppm were taken for the assays. All the bioremediation assays were done in the soil with phenol dispersed in water and remediation rates were observed for 24 hours, 48 hours, 72 hours, 96 hours and 120 hours. The initial concentration of phenol was increased eventually and the rate of bioremediation was estimated using 4-amino anti pyrine method. The phenol degradation activity of the gut microflora of the earthworm along with the soil microflora was also observed on a formulated media. The amount of phenol bioremediated was found higher in case of earthworm and not the microflora solely. It was found to be 30 ppm in 48 hours when the initial concentration was 50 ppm.

Biodiversity conservation is a significant challenge for urban planning and management. When new urban development strategies are introduced, their effects on urban biodiversity are often unknown and may have serious consequences for conservation. A relatively new urban development strategy for sustainable urban water cycle management is Water Sensitive Urban Design (WSUD). While this strategy has been implemented in Australia over the past decade, little is known about the impacts on biodiversity from its application. A field investigation was conducted on 12 bioretention basins, which are a type of vegetated WSUD system. The study used invertebrates captured through pitfall trapping as biodiversity indicators and was conducted in the Melbourne area during the summer of 2006-2007. It investigated the effect of ten habitat factors separately and as group factors on biodiversity of the systems. It also examined how invertebrates were distributed within these WSUD systems. The results suggested that greater leaf/plant litter depth or a combination of greater leaf/plant litter depth and larger number of plant taxa is a significant contributor to biodiversity in bioretention basins. Therefore, the design and management of bioretention basins should consider increasing these habitat factors as key elements to promote biodiversity. The distribution pattern of invertebrates within the systems increased from the edges towards the centre suggesting that designing the sites should consider shape and size to create larger interior habitats for enhancing biodiversity. The results of this study are important for the design and management of bioretention basins to improve biodiversity conservation in urban environments.

Overview of biodiversity in wastewaters Biodiversity is complex in wastewaters, involving micro/macro flora and fauna, and viruses. Interactions among the biota range from mutualism to predation. Community and trophic level cascades dominate the processes. Algal diversity in wastewaters Algae, include both micro and macrophytes. Crucial for the proper functioning of food webs. Cyanophyceae, Chlorophyceae and Bacillariophyceae predominate in most types of wastewaters. Fungi, bacteria and viruses also present with algae, but less investigated. Nutrient removal Chlorella spp.-most investigated alga in wastewaters, especially for N/P sequestration. Consortial approach more effective in nutrient recycling and bioremediation. Algal polycultures, algae-bacteria/algae-fungi consortia mostly utilized. Applications of harvested biomass Feasibility dependent upon type of wastewater, environmental/cultural conditions and end users. Untreated, primary and secondary treated wastewaters evaluated. 18-33% lipid content reported using Chlorella or mixed cultures. Potential for up-scaling and commercialization, but comparison of published work difficult due to heterogeneity in experimentation. Algae cultivation techniques Cultivation of algae in open ponds pose significant challenges. Microalgal communities more robust and productive. High rate algal ponds most advantageous and effective. Advanced Integrated Wastewater Pond Systems and Algal scrubbers gaining significance. Future perspective Algae based wastewater treatment gaining importance globally, especially in developing countries. Environment friendly option, which can reduce CO 2 emissions, generate valuable biomass using domestic, agricultural or industrial wastewaters. Biomass generated can meet energy needs as biocrude/biogas. Biofilms/algal mats ideal for treating low strength wastewaters. Life cycle assessments essential for enhancing economic and environmental sustainability. Cost-effective technologies need to be developed with reduced footprint area for algae cultivation to treat wastewater and produce biomass for biofuel applications.

Bioremediation of petroleum hydrocarbon contaminated soil is studied using the slurry bioreactor. This method overcomes the limitations of the mass transfer rates and thereby improves the extent of degradation as compared to the conventional bioremediation techniques. Soil from crude oil producing well site was used for the study. Three different microorganisms were isolated and their bio-surfactant producing capacity was studied. The three best organisms were used for bioremediation using slurry bioreactor. The reduction in the Total Petroleum Hydrocarbon (TPH) for different microorganisms was studied over the period of 72 hours. The variation in other parameters such as Dissolved Oxygen (DO), pH and Colony Forming Units (CFU/ml) was studied. The criterion for selection of microorganism suitable for the bioremediation process using slurry reactor is proposed. The current work highlights the importance of the treatability studies in the bioremediation of contaminated soil for large scale applications of slurry reactor technology.

Polyaromatic hydrocarbons (PAHs) are major and recalcitrant pollutants of the environment and their removal presents a significant problem. Phytoremediation has shown much promise in PAH removal from contaminated soil, but may be inhibited because the plant experiences phytotoxic effects from low-molecular-weight PAHs such as naphthalene. This paper describes the construction of a naphthalene-degrading endophytic strain designated Pseudomonas putida VM1441(pNAH7). This strain was found to be an efficient colonizer of plants, colonizing both the rhizosphere and interior root tissues. The inoculation of plants with P. putida VM1441(pNAH7) resulted in the protection of the host plant from the phytotoxic effects of naphthalene. When inoculated plants were exposed to naphthalene, both seed germination and plant transpiration rates were higher than those of the uninoculated controls. The inoculation of plants with this strain also facilitated higher (40%) naphthalene degradation rates compared with uninoculated plants in artificially contaminated soil.

Pit lakes (abandoned flooded mine pits) represent a potentially valuable resource to mining companies, the environment and community, if appropriate water quality can be achieved. However, the water is often of low pH with high dissolved metal concentrations. In Western Australia coal pit lakes are acidic (pH 3-5) but with low concentrations of sulfate and metals.

Coal is one of the most commonly utilized fossil fuel for energy production across the globe leading to higher amount of emission of sulfur dioxide (SO2) in the atmosphere. Combustion of coal containing higher contents of sulfur is a major factor responsible for acid rain and associated environmental degradation. The currently used physico-chemical approaches for removal of sulfur from coal are expensive, toxic in nature and inappropriate for different types of coal. The application of microbial resources for removal of sulfur from coal is an ecofriendly technique and could be successfully employed at industrial scale after laboratory scale process optimization. The process of sulfur removal by microbes is carried out by enzymes and is considerably influenced by different factors including pH, temperature, nutrient composition, shaking or standing condition, coal types and most importantly type of microorganisms used. Different bacteria and fungi isolated from coal contaminated site as well as non-contaminated site exhibiting sulfur removal potential can be used as next generation tool for development of clean coal technology. Furthermore, through the application of modern genetic manipulation techniques, enhanced expression of genes responsible for desulfurization can be performed in order to accelerate the process of sulfur removal from coal. The present chapter is prepared with an aim to discuss the diverse microbial population participating in desulfurization, their efficiency, mechanism of sulfur elimination, role of important environmental factors along with possible applications and challenges in industrial scale sulfur removal.

The combined remediation mechanisms of volatilization and biodegradation in the vadose zone were investigated for naphthalene remediation at a creosote-contaminated site where a poplar tree-based phytoremediation system has been installed. Concurrent field and laboratory experiments were conducted to study the transport and biodegradation of naphthalene in the vadose zone. Soil gas sampling showed that more than 90% of the naphthalene vapors were biodegraded aerobically within 5-10 cm above the water table during the summer months. Peak naphthalene soil gas concentrations were observed in the late summer, corresponding with peak naphthalene aqueous concentrations and the minimum saturated zone thickness. An analytical solution was developed for vapor transport where the diffusion coefficient and firstorder biodegradation rate vary vertically in two discrete zones. First-order aerobic biodegradation rates in laboratory columns using unsaturated site soil ranged from 5 to 28 days-1 with a mean rate of 11 days-1. The observed naphthalene mass flux at the source (3.3-22 µg cm-2 d-1) was enhanced by aerobic biodegradation and was greater than the mean observed flux in the abiotic control column and the maximum theoretical mass flux by factors of 7 and 28, respectively.

Culturable hererotrophic bacteria Vibrios Filter-feeding activity Bioremediation Bioindicator Spongia officinalis Apulian coasts a b s t r a c t This study was carried out to evaluate the microbiological accumulation capability of the demosponge Spongia officinalis var. adriatica. Six microbiological parameters were researched in two sampling periods in the water and in reared sponge samples coming from sites with different degrees of microbial contamination: an off-shore fish farm displaced off the Apulian coast (Southern Adriatic Sea) and a no-impacted area displaced into the Marine Protected Area of Porto Cesareo (Apulian coast-Ionian Sea). We detected the density of culturable heterotrophic bacteria by spread plate on marine agar, total culturable bacteria at 37 1C on Plate Count Agar and vibrios on thiosulphate-citrate-bile-sucrose-salt (TCBS) agar. Total and fecal coliforms as well as fecal streptococci concentrations were detected by the MPN method. Bacterial densities were always higher in the sponge homogenates compared with the corresponding seawater in the sampling points and in both sampling periods. As regard vibrios, total culturable bacteria at 37 1C and fecal streptococci concentrations, the highest values were observed in the sponge samples coming from the off-shore fish farm during the summer period. The ability of Spongia officinalis var. adriatica to accumulate the microbial pollution indicators suggests that this species can be employed as a bioindicator for monitoring water quality.

The extraction behaviour of Ni(II), Zn(II), Cd(II), Hg(II) and Pb(II) from aqueous solution, as function of pH, has been investigated with chloroform solutions of 1-phenyl-3-hydroxy-4-dodecyldithiocarboxylate-5-pyrazolone (HDTC-12) as extractant. In each case, the extracted species was found to be M(DTC-12)2 and the extraction constants were deduced by non-linear regression analysis. The results demonstrate that this ligand extracts selectively Hg(II) from Cd(II) as well as from Pb(II).

The present study was aimed to assess the ability of Bacillus sp. JDM-2-1 and Staphylococcus capitis to reduce hexavalent chromium into its trivalent form. Bacillus sp. JDM-2-1 could tolerate Cr(VI) (4800 µg/mL) and S. capitis could tolerate Cr(VI) (2800 µg/mL). Both organisms were able to resist Cd 2+ (50 µg/mL), Cu 2+ (200 µg/mL), Pb 2+ (800 µg/mL), Hg 2+ (50 µg/mL) and Ni 2+ (4000 µg/mL). S. capitis resisted Zn 2+ at 700 µg/mL while Bacillus sp. JDM-2-1 only showed resistance up to 50 µg/mL. Bacillus sp. JDM-2-1 and S. capitis showed optimum growth at pH 6 and 7, respectively, while both bacteria showed optimum growth at 37°C. Bacillus sp. JDM-2-1 and S. capitis could reduce 85% and 81% of hexavalent chromium from the medium after 96 h and were also capable of reducing hexavalent chromium 86% and 89%, respectively, from the industrial effluents after 144 h. Cell free extracts of Bacillus sp. JDM-2-1 and S. capitis showed reduction of 83% and 70% at concentration of 10 µg Cr(VI)/mL, respectively. The presence of an induced protein having molecular weight around 25 kDa in the presence of chromium points out a possible role of this protein in chromium reduction. The bacterial isolates can be exploited for the bioremediation of hexavalent chromium containing wastes, since they seem to have a potential to reduce the toxic hexavalent form to its nontoxic trivalent form.

An underwater device, able to favour the sea auto-cleaning capacities, is herein described. This system, called MUDS (marine underwater depuration system), consists of a percolating filter and is placed at sea over an urban sewage outflow of a submarine pipeline. Due to the ...

The kinetics study of effluents from food and detergent industries were carried out. Two different bacteria Pseudomonas spp and Bacillus spp were isolated from food effluent (FE) and detergent effluents (DE) and were used for their bioremediation respectively. Reductions in the chemical oxygen demand (COD) of the effluents were studied as indication of bioremediation of the effluents. The overall result showed that the reduction in the chemical oxygen demand (COD) for the food effluent and detergent effluent at 5g of micro-organism (OW5g) was 78.70% and 84.47% respectively while those of 10g of micro-organism (OW10g) were 91.11% and 87.76% respectively. At 50% dilution of the effluents and 5g of the micro-organism (DW5g) the reduction in COD was 96.83% and 88.73% for food effluent and for detergent effluent respectively. The reductions in COD were subjected to zero and first order kinetics. The rate constant for COD reduction at 5g of micro-organism for zero order and first order kinetics were (COD-F 33.8mg/l/d and 0.061d -1 ) and (COD-D 31.7 mg/l/d and 0.067d -1 ) respectively. The rate constants for COD reduction at 10g of micro-organism for zero order and first order kinetics were (COD-F 31.09mg/l/d and 0.123d -1 ) and (COD-D 32.4mg/l/d and 0.085d -1 ), while those at 50% dilution with 5g of micro-organism was (COD-F 30.8mg/l/d and 0.786d -1 ) and (COD-D 28.45mg/l/d and 0.14d -1

Polyurethanes (PU) are the sixth most produced plastics with around 18-million tons in 2016, but since they are not recyclable, they are burned or landfilled, generating damage to human health and ecosystems. To elucidate the mechanisms that landfill microbial communities perform to attack recalcitrant PU plastics, we studied the degradative activity of a mixed microbial culture, selected from a municipal landfill by its capability to grow in a water PU dispersion (WPUD) as the only carbon source, as a model for the BP8 landfill microbial community. The WPUD contains a polyether-polyurethane-acrylate (PE-PU-A) copolymer and xenobiotic additives (N-methylpyrrolidone, isopropanol and glycol ethers). To identify the changes that the BP8 microbial community culture generates to the WPUD additives and copolymer, we performed chemical and physical analyses of the biodegradation process during 25 days of cultivation. These analyses included Nuclear magnetic resonance, Fourier transform infrared spectroscopy, Thermogravimetry, Differential scanning calorimetry, Gel permeation chromatography, and Gas chromatography coupled to mass spectrometry techniques. Moreover, for revealing the BP8 community structure and its genetically encoded potential biodegradative capability we also performed a proximity ligation-based metagenomic analysis. The additives present in the WPUD were consumed early whereas the copolymer was cleaved throughout the 25-days of incubation. The analysis of the biodegradation process and the identified biodegradation products showed that BP8 cleaves esters, CC , and the recalcitrant aromatic urethanes and ether groups by hydrolytic and oxidative mechanisms, both in the soft and the hard segments of the copolymer. The proximity ligation-based metagenomic analysis allowed the reconstruction of five genomes, three of them from novel species. In the metagenome, Frontiers in Microbiology | www.frontiersin.org 1

Plant species, spatial variability in plant diversity and vegetation cover were recorded at a French timber treatment site with Cu-contaminated soils (65-2600 mg/kg). Shoot biomass, shoot Cu concentration and accumulation were determined for each plant species found on 168 quadrats with increasing total Cu in soil and soil solution. A total of 91 species occurred on the site including four considered as invasive (Cyperus eragrostis, Phytolacca americana, Senecio inaequidens, and Sporobolus indicus). Species richness, Shannon index, vegetation cover and plant biomass decreased as soil Cu increased. At low soil Cu, members of the Poaceae were most frequent followed by Fabaceae, Rosaceae, and Asteraceae. At high soil Cu, Poaceae were again most frequent. Species known to form Cu-tolerant populations, i.e. Agrostis capillaris, A. stolonifera and Rumex acetosella were present. Shoot Cu concentration and accumulation were higher in plants growing in the most contaminated soils. At 2142 mg Cu/kg soil, shoot Cu accumulation peaked at 6 mg Cu/m² in A. capillaris, and its shoot Cu concentration (364 mg Cu/kg dry weight) exceeded the fodder Cu threshold for domestic livestock. In less Cu-contaminated soils some candidates were identified for sustainable phytoremediation with a potential financial return.

The revolution in metal industries worldwide and anthropogenic activities has added significantly large amount of metals into the natural environment leading to hazardous impact on diverse organisms. Remediation of metal contaminants using physicochemical techniques is expensive, ecologically unsafe, and secondary product generating calling for the judicious application of biological agents. The microbes inhabiting in metal-polluted soil and water, during the long course of evolution, have evolved the intricate mechanism of metal oxidation by employing cellular processes. The potential ability of microorganisms in oxidizing metals also possesses advantageous application in extraction of heavy metals, thereby serving as a foundation for contaminant treatment. Sometimes, the metals used by these microbes are utilized as electron donor to derive energy during the respiratory processes. For instance, under natural environmental conditions ferrous form of iron is rapidly oxidized to ferric iron and offers a strong substrate for its oxidation. Since the electrode potential of ferrous/ferric under acidic condition is high enough, only oxygen molecule with the sufficient availability of protons can be preferred as electron acceptor and subsequent formation of water molecule. Therefore ferrous iron can serve as electron donor only under aerobic environment. The process of iron oxidation occurs spontaneously if the pH is not very acidic. However, under strong acidic conditions, acidophilic microbes, especially bacteria, catalyze the oxidation of ferrous iron eventually resulting into formation of biogenic iron oxides. The oxidation of manganese [Mn(II)] to produce insoluble manganese oxides [Mn(III) and Mn(IV)] is also evident in different bacterial and fungal species directing their utilization for toxic substance remediation. Microbially facilitated Mn(II) oxidation under circumneutral environment has been recorded multifold greater as compared to abiotically catalyzed processes and thereby indicates the promising potential in generation of various oxides and hydroxides under aqueous and terrestrial environment. The formation of insoluble manganese oxides has environmentally important contribution in regulating the biogeochemical cycling of multiple elements occurring in the natural ecosystem. Moreover, biogenic manganese oxides can sequester organic as well as inorganic metal contaminants of hazardous nature. The arsenite [As(III)]-oxidizing bacteria are mostly documented in arsenic-enriched water and soil samples. The conversion of arsenite to arsenate [As(V)] facilitated by aio genes is considered as a mechanism of detoxification. Oxidative transformation of As(III) to more adsorptive As(V) by microbiological activities is quite helpful in treatment of arsenic-laden water and wastewater. The process of As(III) oxidation linked with reduction of nitrate causing reduced bioavailability of metalloid has also been demonstrated as a mechanism of alleviation of arsenic toxicity. The presence of arsenite-oxidizing microorganism in aqueous and terrestrial environment is intimately linked with immobilization.

The present study reports on tolerance study of heavy metals by endophytic fungi. Endophytic fungi isolated from agriculture field used for the study were Phomopsis sp, Fusarium sp.1, Colletotrichum sp, Fusarium sp.2 and Phoma sp. To test the effect of different metal on varying concentration of heavy metal, the heavy metal of different concentration were added to the PDA media range varying from 50-600ppm. Fungal endophytes on PDA medium without heavy metal served as control. PDA plates with metal ions were inoculated with fresh culture of fungus and were allowed to incubate at 27 °C for 7 days. The different test isolates at the different concentrations of the test metals exhibited varying degree of effect on mycelia formation. The results indicated at 600 ppm metal concentration, the most heavy metals tolerant endophytic fungus was Colletotrichum sp (resistant to all metals under study) followed by Fusarium sp.1 and Phoma sp (resistant to Cu (II), Zn (II), Pb (II) and Cd (II)). Phomopsis sp and Fusarium sp.2 were tolerant to Cu (II), Zn (II) and Pb (II) and Zn (II), Pb (II) and Cr (VI) respectively. The ability of fungal endophytes to grow in the presence of heavy metals is always be an added advantage in the treatment of waste water where role of microorganisms is to degrade organic matter through biological process.

Cryptococcus albidus, isolated from the sediments of Century Pulp and Paper Mill, Lalkuan, Nainital, Uttarakhand, India, produced a copper containing oxidase, laccase, that was capable of degrading environmental pollutants. Bagasse was the most efficient inducer for laccase production. The Taguchi approach was used to optimize the growth media for five factors, i.e., pH, copper sulphate, carbon, nitrogen, and the inducer at four levels using an M-16 orthogonal array. The optimum conditions for laccase production were pH (6), CuSO4 (2 mmol/L), meat peptone (0.5%), glucose (0.1%), and bagasse (1.0%). After optimization, laccase production increased seven times from 32 to 219 IU/mg. The inducer (bagasse) had maximum effect on laccase production leading to 52% increase, while pH had minimum effect with 7% increase. Growth media with laccase activity (2 U/mL) was applied for the bioremediation of dyes, effluent, and chemical compounds. These experiments showed that the growth media with laccase activity (2 U/mL) produced by Cryptococcus albidus had good potential for bioremediation of toxic and recalcitrant compounds. Further, the laccase enzyme extracted from the growth media was fractionated by DEAE-cellulose ion-exchange chromatography, and the molecular weight of the enzyme determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) was found to be 64 kDa. The activity of laccase was confirmed by native PAGE, in which ABTS was used for staining gel.

Cacao (Theobroma cacao) worldwide has increased its area sown and yield per hectare, however currently producers are facing strong legislation issued by the European Union regarding the maximum levels of lead and cadmium that must have chocolates that contain an amount greater than or equal to 50 % cocoa solids. Based on a review of the work carried out around the world and published in the last three years in global databases are presented, in the first instance, the problems caused in people by the consumption of food contaminated by heavy metals and the routes through which the cocoa can be contaminated, from its planting to its processing. The remediation techniques (phytoremediation and bioremediation) that have obtained good results regarding the cleaning of contaminated soils or that avoid the transfer of the contents of lead and cadmium from the soil to several Crops of commercial interest to have options of potential application in the cacao areas of Colombia or anywhere in the world. The results show the importance of implementing an integrated soil remediation system that includes the gradual incorporation of native trees, herbaceous plants, aquatic plants, biochar, bacteria and arbuscular mycorrhizae.

The ability of brown-rot fungi (BRF) to eliminate DDT in artificially and historically contaminated soil was investigated to determine whether the BRF would be suitable for the bioremediation of DDT in soil. Gloeophyllum trabeum, Fomitopsis pinicola and Daedalea dickinsii showed an ability to eliminate DDT in artificially contaminated sterilized (SL) and un-sterilized (USL) soils. The addition of Fe 2þ to the soil system enhanced the ability of some BRF to eliminate DDT. In the contaminated SL soil, the DDT was eliminated by approximately 41%, 9% and 15% by G. trabeum, F. pinicola and D. dickinsii, respectively. Compared with the controls, in the USL soil approximately 43%, 29% and 32% of DDT was eliminated and approximately 20%, 9% and 26% of DDD (1,1-dichloro-2,2-bis (4-chlorophenyl) ethane) was detected as a metabolic product with G. trabeum, F. pinicola and D. dickinsii, respectively. Of the BRF, G. trabeum demonstrated the greatest ability to eliminate DDT both in the SL and USL soils. G. trabeum was applied to a historically contaminated soil which had a DDT concentration more than three times the artificially contaminated soil. G. trabeum remediated about 64% of the initial DDT with the addition of Fe 2þ . There were no significant differences in the results with or without the addition of Fe 2þ , indicating that G. trabeum can be used directly for the degradation of DDT in soil without any other additional treatment. This study identified that G. trabeum is the most promising BRF for use in the bioremediation of DDT contaminated soil.

Methyl parathion (MeP) is a very hazardous pesticide freely used in agriculture in Mexico. This pesticide and others, arriving through different processes, exert significant effects on water quality with serious consequences for environmental and human health. This study evaluates the removal efficiency of common cattail Typha latifolia L. on MeP in water and artificial sediments. The effects of the pesticide on this macrophyte after 10 days of exposure were determined using a concentration range of 0-200 mg l À1 , 198.1 ± 1.79 g average biomass, pH 7.0, 18-22°C temperature and natural daylight/darkness periods, using chlorophyll production as a biomarker. Removal kinetics were conducted under similar conditions on days 0, 3, 7, 9, 11 and 14 of exposure, using 6 mg l À1 in each system. Pesticide concentration, chlorophyll content and glutathione S-transferase (GST) activity were quantified. Results show a high removal efficiency of cattails on MeP in water and sediments relative to controls. An increase in GST activity and a decline in chlorophyll content in the test systems were not significantly different relative to controls. Cattails may thus be a good candidate for development of a phytoremediation system for MeP-contaminated water and artificial sediments.

Plant species, spatial variability in plant diversity and vegetation cover were recorded at a French timber treatment site with Cu-contaminated soils (65-2600 mg/kg). Shoot biomass, shoot Cu concentration and accumulation were determined for each plant species found on 168 quadrats with increasing total Cu in soil and soil solution. A total of 91 species occurred on the site including four considered as invasive (Cyperus eragrostis, Phytolacca americana, Senecio inaequidens, and Sporobolus indicus). Species richness, Shannon index, vegetation cover and plant biomass decreased as soil Cu increased. At low soil Cu, members of the Poaceae were most frequent followed by Fabaceae, Rosaceae, and Asteraceae. At high soil Cu, Poaceae were again most frequent. Species known to form Cu-tolerant populations, i.e. Agrostis capillaris, A. stolonifera and Rumex acetosella were present. Shoot Cu concentration and accumulation were higher in plants growing in the most contaminated soils. At 2142 mg Cu/kg soil, shoot Cu accumulation peaked at 6 mg Cu/m² in A. capillaris, and its shoot Cu concentration (364 mg Cu/kg dry weight) exceeded the fodder Cu threshold for domestic livestock. In less Cu-contaminated soils some candidates were identified for sustainable phytoremediation with a potential financial return.

This research work evaluates the impact of stormwater infiltration on the removal of organics, solids, nitrogen and phosphorus in a LECA-based horizontal subsurface flow constructed wetland. Stormwater runoff for the period between January 2008 and June 2010 (30 months) was estimated for the drainage basin of the Vila Fernando wastewater treatment plant (constructed wetland system) and it was observed proportionality between the increase in surface runoff and the infiltration flow rate that reached the plant. The average stormwater infiltration rate that reached the plant was 67.4 m(3) d(-1) (77% of the influent flow rate into the plant). The 30 month monitoring campaign set up at one of the reed beds showed that stormwater infiltration led to a high variation of the hydraulic loading rate (HLR) throughout the bed, which affected its performance in the removal of organic matter, suspended solids and nitrogen. For a HLR below 20 cm d-1 the removal efficiencies for BOD5, COD and TSS doubled. The removal of nitrogen was too low and was associated with the weak development of nitrifying biofilm and the poor growth of reeds. However, it was observed a good relationship between the applied and removed loads for most of the parameters, which seems to indicate that the organic, solid, nitrogen and phosphorus loading rates influenced the respective removal rates. The use of a bed material with high specific surface area, such as LECA, can only improve the treatment capacity of horizontal subsurface flow systems if the organic and solid loading rates, as well as the HLR, can be effectively controlled.

Yarrowia lipolytica is a fungus that degrades hydrophobic substrates very efficiently. The fungus displays several important characteristics that have encouraged researchers to study various basic biological and biotechnological applications in detail. Although the organism has been used as model system for studying dimorphism, salt tolerance, heterologous protein expression, and lipid accumulation, there are no recent reviews on the environmental and industrial applications of this organism. Included here are applications in bioremediation of environments contaminated with aliphatic and aromatic compounds, organic pollutants, 2,4,6-trinitrotoluene, and metals. A variety of industrially important recent processes for the synthesis of β-hydroxy butyrate, L-dopa, and emulsifiers have also been reviewed. Production of unique inherent enzymes (inulinases, α-mannosidases), novel applications of esterases and lipases, and the use of the fungus for heterologous expression of biotechnologically relevant products have also been highlighted. The review while entailing a general overview focuses critically on some of the recent advances on the applications of this yeast. The examples cited here demonstrate the use of wild-type, mutant as well as genetically manipulated strains of Y. lipolytica for the development of different products, processes, and technologies. This also throws light on how a single organism can be versatile with respect to its metabolic abilities and how it can be exploited for a variety of purposes. This review will thus form a base for future developments in this field.

En la presente investigación se ha aplicado y comparado el método de bioestimulación con el de atenuación natural sobre suelos contaminados con hidrocarburos en la zona norte del país. La atenuación natural es la degradación generada por los microorganismos del suelo sin adición de nutrientes, mientras que en la bioestimulación se le da las condiciones de aireación, humedad y nutrientes para que los microorganismos puedan tener mayor eficiencia de remoción por su
mayor actividad, así como una mayor división de los mismos.

Otro parámetro de comparación es la relación de nutrientes C:N:P que afecta también a la remoción de hidrocarburos. El principal factor de medida de remoción ha sido establecido en función al análisis de TPH (hidrocarburos totales de petróleo).

Autores: Huguez Ames, Tecsup (Perú)/ Lizardo Visitación, Rosa Altuna y Lena Téllez, UNALM (Perú)

Additional index words. ferns, foliage plant, phytoremediation, sick building syndrome, volatile organic compounds Abstract. The efficiency of volatile formaldehyde removal was assessed in 86 species of plants representing five general classes (ferns, woody foliage plants, herbaceous foliage plants, Korean native plants, and herbs). Phytoremediation potential was assessed by exposing the plants to gaseous formaldehyde (2.0 mLÁL -1 ) in airtight chambers (1.0 m 3 ) constructed of inert materials and measuring the rate of removal. Osmunda japonica, Selaginella tamariscina, Davallia mariesii, Polypodium formosanum, Psidium guajava, Lavandula spp., Pteris dispar, Pteris multifida, and Pelargonium spp. were the most effective species tested, removing more than 1.87 mgÁm -3 Ácm -2 over 5 h. Ferns had the highest formaldehyde removal efficiency of the classes of plants tested with O. japonica the most effective of the 86 species (i.e., 6.64 mgÁm -3 Ácm -2 leaf area over 5 h). The most effective species in individual classes were: ferns-Osmunda japonica, Selaginella tamariscina, and Davallia mariesii; woody foliage plants-Psidium guajava, Rhapis excels, and Zamia pumila; herbaceous foliage plants-Chlorophytum bichetii, Dieffenbachia 'Marianne', Tillandsia cyanea, and Anthurium andraeanum; Korean native plants-Nandina domestica; and herbs-Lavandula spp., Pelargonium spp., and Rosmarinus officinalis. The species were separated into three general groups based on their formaldehyde removal efficiency: excellent (greater than 1.2 mgÁm -3 formaldehyde per cm 2 of leaf area over 5 h), intermediate (1.2 or less to 0.6), and poor (less than 0.6). Species classified as excellent are considered viable phytoremediation candidates for homes and offices where volatile formaldehyde is a concern.

Page 1. Population Changes of Soil Microbial Communities Induced by Hydrocarbon and Heavy Metal Contamination Roger Dobler, Matthias Saner, and Reinhard Bachofen* University of Zurich, Institute for Plant Biology, Zollikerstr. 107, CH-8008 Zurich, Switzerland ...