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Environmental context Endocrine disrupting compounds (EDCs) are among the most recently targeted micropollutants detected in wastewater treatment plant (WWTP) effluents and in aquatic environments. There is a need for the development of robust analytical methods for most relevant estrogenic EDCs. This study provides optimisation of analytical techniques and addresses several relevant aspects that are often overlooked in the literature. The method was finally successfully employed for the analysis of WWTP effluents. Abstract Two analytical approaches – liquid chromatography–tandem mass spectrometry (LC-MS/MS) and gas chromatography–tandem mass spectrometry (GC-MS/MS) methods – were compared for the simultaneous determination of the 19 most important oestrogenic endocrine disrupting chemicals (EDCs), such as 17β-oestradiol, oestrone, 17α-ethinyloestradiol, bisphenol A and triclosan in wastewater treatment plant effluents. To lower the instrument limits of detection (ILODs), a derivatisation step preceded detection in both methods. The stability, sensitivity and ease of use of dansylation (Dns) for LC-MS/MS and trimethylsilylation (TMS) for GC-MS/MS derivatives were evaluated before method validation. TMS derivatisation products were highly unstable over time. Parameters such as susceptibility to matrix effects and the stability of monodansylated and didansylated derivatisation products of phytohormones are discussed. Lower ILODs of highly potent EDCs (0.11 ng mL−1 for 17β-oestradiol, 0.01 ng mL−1 for 17α-ethinyloestradiol and 0.22 ng mL−1 for oestrone) and stability of derivatisation products within 7 days were achieved using LC–MS/MS; therefore, further validation of this method at environmentally relevant concentrations was conducted. The method limits of detection (MLODs) met the requirements of the European Union defined in Directive 2008/105/ES for 17α-ethinyloestradiol (0.035 ng L−1) and 17β-oestradiol (0.4 ng L−1). Twenty samples of wastewater treatment plant effluent from the Czech Republic were screened using LC-MS/MS. Fifteen of the EDCs were detected in at least one sample. The most abundant EDCs were bisphenol A, with a concentration up to 1107 ng L−1, and triclosan, with a concentration up to 76 ng L−1. No seasonal trend between late spring and autumn samples was observed in the frequency or quantity of analytes.

Secondary metabolites of cyanobacteria and algae released during algal blooms often exhibit toxic effects, but only a small number of the metabolites are the subject of routine analytical screenings. Alternatively, ecotoxicological assays offer a better representation of the overall negative effects. The aim of this work was to compare multiple assays in their sensitivity towards cellular algal organic matter (COM) of the toxin-producing cyanobacterium Microcystis aeruginosa. Multiple endpoints were investigated: mortality, growth inhibition, bioluminescence inhibition, genotoxicity, endocrine-disrupting effects, oxidative stress, and the induction of ethoxyresorufin-O-deethylase (EROD). Three rainbow trout (Oncorhynchus mykiss) cell lines as well as representatives of bacteria, yeasts, algae, vascular plants, and crustaceans were employed, and the results were expressed per mg of dissolved organic carbon (DOC) in the COM. M. aeruginosa COM was toxic to the RTgill-W1, RTG-2, and RTL-W1 cell lines (EC50 values ranging from 0.48 ± 0.02 to 1.9 ± 0.1 mgDOC/L), to the crustacean Thamnocephalus platyurus (LC50 = 20 ± 1 mgDOC/L), and to Lepidium sativum (IC50 = 241 ± 13 mgDOC/L). In contrast, no effect was observed for bacteria and yeasts, and the growth of the alga Desmodesmus subspicatus was even stimulated. No genotoxicity, endocrine-disrupting effects or increase in oxidative stress or EROD activity was detected. The content of six microcystins (MC-LR, MC-RR, MC-YR, MC-LY, MC-LW, and MC-LF), anatoxin-a, cylindrospermopsin, and nodularin in the M. aeruginosa COM was determined by liquid chromatography–tandem mass spectrometry. An artificially prepared mixture of the detected cyanotoxins in the corresponding concentrations did not induce response in the O. mykiss cell lines and T. platyurus, suggesting that other cyanobacterial metabolites are responsible for the toxicity of M. aeruginosa.

Biologically active micropollutants that contain diverse phenolic/aromatic structures are regularly present in wastewater effluents and are even found in drinking water. Advanced green technologies utilizing immobilized laccase and/or peroxidase, which target these micropollutants directly, may provide a reasonable alternative to standard treatments. Nevertheless, the use of these enzymes is associated with several issues that may prevent their application, such as the low activity of laccase at neutral and basic pH or the necessity of hydrogen peroxide addition as a co-substrate for peroxidases. In this study, the activity of laccase from Trametes versicolor and horseradish peroxidase was evaluated across a range of commonly used substrates (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), syringaldazine, and guaiacol). Moreover, conditions for their optimal performance were explored along with an assessment of whether these conditions accurately reflect the effectivity of both enzymes in the degradation of a mixture of bisphenol A, 17α-ethinylestradiol, triclosan, and diclofenac in tap drinking water and secondary wastewater effluent. Laccase and horseradish peroxidase showed optimal activity at strongly acidic pH if ABTS was used as a substrate. Correspondingly, the activities of both enzymes detected using ABTS in real waters were significantly enhanced by adding approximately 2.5% (v/v) of McIlvaine’s buffer. Degradation of a mixture of micropollutants in wastewater with 2.5% McIlvaine’s buffer (pH 7) resulted in a substantial decrease in estrogenic activity. Low degradation efficiency of micropollutants by laccase was observed in pure McIlvaine’s buffer of pH 3 and 7, compared with efficient degradation in tap water of pH 7.5 without buffer. This study clearly shows that enzyme activity needs to be evaluated on micropollutants in real waters as the assessment of optimal conditions based on commonly used substrates in pure buffer or deionized water can be misleading.

Copper oxide nanoparticles (CuO NPs) are widely used in industry. Once released, they can enter the soil system and endanger organisms living in this environment. Therefore, monitoring the NP impact on soil organisms and identification of suitable biomarkers associated with NP pollution are required. In this study, immune effector cells of the earthworm Eisenia andrei, amoebocytes, were exposed to environmentally relevant sublethal concentrations of CuO NPs (1, 10, and 100 μg mL−1 of Cu) and their impact on the cellular and subcellular levels, as well as on the mRNA levels of molecules involved in the defense reactions, was assessed in vitro. CuO NPs decreased the viability of both amoebocyte subpopulations by 40% at the highest concentration tested (100 μg mL−1 of Cu). Further, CuO NPs caused significant attenuation of the phagocytic function of hyaline amoebocytes after 6 and 24 hours of exposure, by 37 and 25%, respectively. The concentration of the lipid peroxidation subproduct, malondialdehyde, was 10 times elevated in cells exposed to CuO NPs (100 μg mL−1 of Cu) after 6 hours of exposure. We hypothesize that malondialdehyde may induce DNA breaks, cell cycle arrest, and subsequent cell death. Electron microscopy showed the interaction between CuO NPs and immune effector cells, amoebocytes. Moreover, aggregates of CuO NPs were shown to be engulfed and located in the cytoplasm of these cells. However, data from all experiments indicate that the observed effects of CuO NPs on earthworm coelomocytes were caused mainly by the dissolved Cu2+ ions derived from nanoparticles (NPs). The determination of effective parameters such as oxidative stress, immune reactivity, and genotoxicity would provide valuable comprehension and data for environmental assessment of NP impact on soil organisms.

In this study, the diversity of bphA genes was assessed in a 13C-enriched metagenome upon stable isotope probing (SIP) of microbial populations in legacy PCB-contaminated soil with 13C-biphenyl (BP). In total, 13 bphA sequence variants (SVs) were identified in the final amplicon dataset. Of these, one SV comprised 59% of all sequences, and when it was translated into a protein sequence, it exhibited 87, 77.4, and 76.7% identity to its homologs from Pseudomonas furukawaii KF707, Cupriavidus sp. WS, and Pseudomonas alcaliphila B-367, respectively. This same BphA sequence also contained unusual amino acid residues, Alanine, Valine, and Serine in region III, which had been reported to be crucial for the substrate specificity of the corresponding biphenyl dioxygenase (BPDO), and was accordingly designated BphA_AVS. The DNA locus of 18 kbp containing the BphA_AVS-coding sequence retrieved from the metagenome was comprised of 16 ORFs and was most likely borne by Paraburkholderia sp. The BPDO corresponding to bphAE_AVS was cloned and heterologously expressed in E. coli, and its substrate specificity toward PCBs and a spectrum of flavonoids was assessed. Although depleting a rather narrow spectrum of PCB congeners, the efficient transformation of flavone and flavanone was demonstrated through dihydroxylation of the B-ring of the molecules. The homology-based functional assignment of the putative proteins encoded by the rest of ORFs in the AVS region suggests their potential involvement in the transformation of aromatic compounds, such as flavonoids. In conclusion, this study contributes to the body of information on the involvement of soil-borne BPDOs in the metabolism of flavonoid compounds, and our paper provides a more advanced context for understanding the interactions between plants, microbes and anthropogenic compounds in the soil.

The removal of algal organic matter (AOM) is a growing concern for the water treatment industry worldwide. The current study investigates coagulation of non-proteinaceous AOM (AOM after protein separation), which has been minimally explored compared with proteinaceous fractions. Jar tests with either aluminum sulphate (alum) or polyaluminium chloride (PACl) were performed at doses of 0.2-3.0 mg Al per 1 mg of dissolved organic carbon in the pH range 3.0-10.5. Additionally, non-proteinaceous matter was characterized in terms of charge, molecular weight and carbohydrate content to assess the treatability of its different fractions. Results showed that only up to 25% of non-proteinaceous AOM can be removed by coagulation under optimized conditions. The optimal coagulation pH (6.6-8.0 for alum and 7.5-9.0 for PACl) and low surface charge of the removed fraction indicated that the prevailing coagulation mechanism was adsorption of non-proteinaceous matter onto aluminum hydroxide precipitates. The lowest residual Al concentrations were achieved in very narrow pH ranges, especially in the case of PACl. High-molecular weight saccharide-like organics were amenable to coagulation compared to low-molecular weight (3 kDa) substances. Their high content in non-proteinaceous matter (about 67%) was the reason for its low removal. Comparison with our previous studies implies that proteinaceous and non-proteinaceous matter is coagulated under different conditions due to the employment of diverse coagulation mechanisms. The study suggests that further research should focus on the removal of low-molecular weight AOM, reluctant to coagulate, with other treatment processes to minimize its detrimental effect on water safety.

Soil microbial communities involved in 13C-labeled cellulose utilization from two contrasting (in terms of vegetation and climatic conditions) forest sites at different elevations were studied by using a laboratory microcosm experiment and a PLFA (phospholipid fatty acid)-SIP (stable isotope probing) approach considering the effects of incubation temperature (0, 10 and 20 °C) and time (1–4 weeks). The amounts of cellulose-13C assimilated by soil microorganisms and the composition of microbial communities utilizing cellulose were site-dependent. Total, bacterial and actinobacterial biomass incorporated higher amounts of 13C in soil from the deciduous forest site (at the lower elevation), while fungal biomass contained increased amounts of 13C in soil from the coniferous forest site (at the higher elevation). Increasing temperatures resulted in increased amounts of 13C assimilated by the different PLFA-based microbial groups, except fungi, and in significant changes in the community structure of cellulose utilizers. Fungi were better adapted to cold conditions than bacteria. Longer incubation times determined an increase in the amount of 13C incorporated into total and bacterial PLFAs but had no effect on the composition of labeled microbial communities.

Nano-scale zero-valent iron (nZVI) began attracting research attention in remediation practice in recent decades as a prospective nanomaterial applicable to various contaminated matrices. Despite concerns about the negative effects of nanomaterials on ecosystems, the number of reliable toxicity tests is limited. We have developed a test based on the evaluation of oxidative stress (OS). The test employed the analysis of a typical OS marker (malondialdehyde, MDA), after exposure of six bacterial strains to the tested nanomaterial. We also attempted to use other OS and cell membrane damage assays, including the determination of glutathione and lactate dehydrogenase, respectively. However, we found that the components of these assays interfered with nZVI; therefore, these tests were not applicable. The MDA assay was tested using nZVI and three newly engineered oxide shell nZVI materials with different oxide thicknesses. Six different bacterial species were employed, and the results showed that the test was fully applicable for the concentrations of nanomaterials used in remediation practice (0.1–10 g/L). MDA was produced in a dose-response manner, and the bacteria showed a similar response toward pure pyrophoric nZVI, reaching EC50 values of 0.3–1.1 g/L. We observed different responses in the absolute production of MDA; however, the MDA concentrations were correlated with the cell membrane surfaces of the individual strains (R > 0.75; P 0.95; P

The involvement of bacterial aromatic ring-hydroxylating dioxygenases (ARHDs) in the degradation of aromatic pollutants, such as polychlorinated biphenyls (PCBs), has been well studied. However, there is considerable speculation as to the origin of this ability. One hypothesis is centered on a connection between the ability to degrade aromatic pollutants and the necessity of soil bacteria to cope with and/or utilize secondary plant metabolites (SPMs). To investigate this connection, we researched the involvement of biphenyl 2,3-dioxygenase (BPDO), an ARHD essential for the degradation of PCBs, in the metabolism of SPMs in the soil bacterium Pseudomonas alcaliphila JAB1, a versatile degrader of PCBs. We demonstrated the ability of the strain JAB1 to transform a variety of SPMs, namely the flavonoids apigenin, flavone, flavanone, naringenin, fisetin, quercetin, morin, and catechin, caffeic acid, trans-cinnamic acid, and the monoterpenes (S)-limonene and (R)-carvone. Of those, the transformation of flavone, flavanone, and (S)-limonene was conditioned by the activity of JAB1-borne BPDO and thus was researched in more detail, and we found evidence for the limonene monooxygenase activity of the BPDO. Furthermore, the bphA gene in the strain JAB1 was demonstrated to be induced by a wide range of SPMs, with monoterpenes being the strongest inducers of the SPMs tested. Thus, our findings contribute to the growing body of evidence that ARHDs not only play a role in the catabolism of aromatic pollutants, but also of natural plant-derived aromatics, and this study supports the hypothesis that ARHDs participate in ecological processes mediated by SPMs.

Metabolites of polychlorinated biphenyls (PCBs)—hydroxylated PCBs (OH-PCBs), chlorobenzyl alcohols (CB-OHs), and chlorobenzaldehydes (CB-CHOs)—were incubated in vitro with the extracellular liquid of Pleurotus ostreatus, which contains mainly laccase and low manganese-dependent peroxidase (MnP) activity. The enzymes were able to decrease the amount of most of the tested OH-PCBs by > 80% within 1 h; the removal of more recalcitrant OH-PCBs was greatly enhanced by the addition of the laccase mediator syringaldehyde. Conversely, glutathione substantially hindered the reaction, suggesting that it acted as a laccase inhibitor. Hydroxylated dibenzofuran and chlorobenzoic acid were identified as transformation products of OH-PCBs. The extracellular enzymes also oxidized the CB-OHs to the corresponding CB-CHOs on the order of hours to days; however, the mediated and nonmediated setups exhibited only slight differences, and the participating enzymes could not be determined. When CB-CHOs were used as the substrates, only partial transformation was observed. In an additional experiment, the extracellular liquid of Irpex lacteus, which contains predominantly MnP, was able to efficiently transform CB-CHOs with the aid of glutathione; mono- and di-chloroacetophenones were detected as transformation products. These results demonstrate that extracellular enzymes of ligninolytic fungi can act on a wide range of PCB metabolites, emphasizing their potential for bioremediation.

A combination of two chromatographic and one enzymatic methods was used for identification of the molecular species of triacylglycerols (TAGs) from Streptomyces avermitilis. Streptomyces avermitliswas cultured on various carbon sources and the ratio of iso- (i-FAs), anteiso- (ai-FAs), and straight-chain- (n-FAs) fatty acids was modified by precursor-directed biosynthesis. Saturated TAGs were separated from other lipids (including TAGs containing unsaturated FAs) using Ag+ ion cartridges. Analysis of TAGs wereperformed by RP-HPLC/ESI+ tandem mass spectrometry. Both the synthetically prepared sn-TAGs and the natural mixture of TAGmolecular species of wereseparated and identified by tandem MS. The structures of synthetic TAGs werefurther confirmed by pancreatic lipase, which cleaves sn-TAGs into sn-2-monoacylglycerols. The retention times (tR) of the individual regioisomers and enantiomers were found to be depend on the structure of the TAGs. If one branched acyl (iso or anteiso) is present in the TAG molecule, then the elution order is enantiomer (n/n/br), opposite enantiomer (br/n/n), regioisomer (n/br/n). In the case where two branched acyls are in the TAG molecule, the order of the elution is different, that is, br/n/br, n/br/br, br/br/n. In all cases, it was further demonstrated that tandem MS of either synthetically prepared TAGs or TAGs obtained from natural material, that is, n-16:0/ai-15:0/n-16:0 and i-16:0/n-15:0/i-16:0 are identical. Unfortunately, it is not possible to distinguish by ESI+ tandem MS such TAGs, which differ only in the branching of the acyls. The results of our analyses of TAGs are in good agreement with previously published data in other streptomycetes.

The interaction of microplastics (MPs) and common environmental organic pollutants has been a frequently discussed topic in recent years. Although the estimated contamination caused by MPs in terrestrial ecosystems is one order of magnitude higher than that in the oceans, experiments have been conducted solely in an aqueous matrix. Therefore, an experiment was carried out with two soils differing in their concentrations of polycyclic aromatic hydrocarbons (PAHs) and polyurethane foams used for scent fences along roads and crop fields. Two types of polyurethane foam (biodegradable and conventional in aged and unaged form) were exposed to soils containing PAHs that originated from historically contaminated localities. The exposure lasted 28 days, and a newly developed three-step procedure to separate MPs from soil was then applied. Biodegradable polyurethane MPs exhibited a strong tendency to accumulate PAHs after 7 days, and their concentrations significantly grew over time. In contrast, the sorption of PAHs on conventional polyurethane MPs was substantially lower (a maximum of 3.6 times higher concentration than that in the soil). Neither type of foam changed their sorption behaviors after the aging procedure. The results indicate that the flexibility of the polyurethane polymeric network could be the main driving factor for the sorption.

The complete genome sequence of Rhodococcus sp. WAY2 (WAY2) consists of a circular chromosome, three linear replicons and a small circular plasmid. The linear replicons contain typical actinobacterial invertron-type telomeres with the central CGTXCGC motif. Comparative phylogenetic analysis of the 16S rRNA gene along with phylogenomic analysis based on the genome-togenome blast distance phylogeny (GBDP) algorithm and digital DNA–DNA hybridization (dDDH) with other Rhodococcus type strains resulted in a clear differentiation of WAY2, which is likely a new species. The genome of WAY2 contains five distinct clusters of bph, etb and nah genes, putatively involved in the degradation of several aromatic compounds. These clusters are distributed throughout the linear plasmids. The high sequence homology of the ring-hydroxylating subunits of these systems with other known enzymes has allowed us to model the range of aromatic substrates they could degrade. Further functional characterization revealed that WAY2 was able to grow with biphenyl, naphthalene and xylene as sole carbon and energy sources, and could oxidize multiple aromatic compounds, including ethylbenzene, phenanthrene, dibenzofuran and toluene. In addition, WAY2 was able to co-metabolize 23 polychlorinated biphenyl congeners, consistent with the five different ring-hydroxylating systems encoded by its genome. WAY2 could also use n-alkanes of various chain-lengths as a sole carbon source, probably due to the presence of alkB and ladA gene copies, which are only found in its chromosome. These results show that WAY2 has a potential to be used for the biodegradation of multiple organic compounds, This research was funded by GREENER-H2020 (EU), grant number 826312, and MICINN/FEDER EU, grant number RTI2018-0933991- B-I00. D.G.-S. was supported by a MECD FPU fellowship program, grant number FPU14/03965. P.S.-L. was supported by the MICINN FPU fellowship program, grant number FPU18/02169. E.B.-R. was supported by the MECD FPU fellowship program, grant number FPU16/05513. J.S., T.C. and O.U. acknowledge Czech Science Foundation grant number 17–00227S, which enabled PCB co-metabolism experiments to be undertaken

The present chapter is describing two pilot-scale experiments and showing the potential of the combined technology (i.e., nanoremediation and bioremediation) for in situ heavy metal removal and dechlorination of chlorinated solvents. Successful applications of the nano-bioremediation approach at two different sites in the Czech Republic contaminated with hexavalent chromium are summarized and evaluated in this chapter. High effectivity of nZVI and the further microbial bioaugmentation step by whey addition resulted in reduction and geofixation of hexavalent chromium in both localities. In addition, a high removal of chlorinated ethenes was observed in the locality 2 after the whey application. The successive abiotic and biotic processes involving the chemical reduction and further microbial bioreduction of chromium and dechlorination of chlorinated ethenes were evaluated by monitoring of physicochemical and biological parameters. The results of both applications of the combined remediation technology clearly prove feasibility and high efficiency of this approach for chromium and chlorinated ethenes removal.

The occurrence of microplastics (MPs) in water intended for human consumption, including water supplied by drinking water treatment plants (DWTPs), has raised considerable attention. DWTPs appear to be capable of removing some of the MPs present in raw water; however, little is known about the efficiency of distinct treatment processes for MP elimination. This study investigated the coagulation of model MPs, i.e., polyvinyl chloride particles

The present study describes a pilot remediation test of a co-mingled plume containing BTEX, chlorinated pollutants and pharmaceuticals. Remediation was attempted using a combination of various approaches, including a pump and treat system applying an advanced oxidation process and targeted direct push injections of calcium peroxide. The remediation process was monitored intensively and extensively throughout the pilot test using various conventional and passive sampling methods, including next-generation amplicon sequencing. The results showed that the injection of oxygen-saturated treated water with residual hydrogen peroxide and elevated temperature enhanced the in situ removal of monoaromatics and chlorinated pollutants. In particular, in combination with the injection of calcium peroxide, the conditions facilitated the in situ bacterial biodegradation of the pollutants. The mean groundwater concentration of benzene decreased from 1349 μg·L− 1 prior to the test to 3 μg·L− 1 within 3 months after the calcium peroxide injections; additionally, monochlorobenzene decreased from 1545 μg·L− 1 to 36 μg·L− 1, and toluene decreased from 143 μg·L− 1 to 2 μg·L− 1. Furthermore, significant degradation of the contaminants bound to the soil matrix in less permeable zones was observed. Based on a developed 3D model, 90% of toluene and 88% of chlorobenzene bound to the soil were removed during the pilot test, and benzene was removed almost completely. On the other hand, the psychopharmaceuticals were effectively removed by the employed advanced oxidation process only from the treated water, and their concentration in groundwater remained stagnant due to inflow from the surroundings and their absence of in situ degradation. The employment of passive sampling techniques, including passive diffusion bags (PDB) for volatile organic pollutants and their respective transformation products, polar organic compound integrative samplers (POCIS) for the pharmaceuticals and in situ soil microcosms for microbial community analysis, was proven to be suitable for monitoring remediation in saturated zones.

This study was performed to test the feasibility of several decontamination methods for remediating heavily contaminated groundwater in a real contaminated locality in the Czech Republic, where a pharmaceuticals plant has been in operation for more than 80 years. The site is polluted mainly by recalcitrant psychopharmaceuticals and monoaromatic hydrocarbons, such as benzene, toluene and chlorobenzene. For this purpose, an advanced oxidation technique employing UV radiation with hydrogen peroxide dosing was employed, in combination with simple aeration pretreatment. The results showed that UV/H2O2 was an efficient and necessary step for degradation of the pharmaceuticals; however, the monoaromatics were already removed during the aeration step. Characterization of the removal mechanisms participating in the aeration revealed that volatilization, co-precipitation and biodegradation contributed to the process. These findings were supported by bacterial metabolite analyses, phospholipid fatty acid analysis, qPCR of representatives of the degradative genes and detailed characterization of the formed precipitate using Mossbauer spectroscopy and scanning electron microscopy. Further tests were carried out in a continuous arrangement directly connected to the wells already present in the locality. The results documented the feasibility of combination of the photo-reactor employing UV/H2O2 together with aeration pretreatment for 4 months, where the overall decontamination efficiency ranged from 72% to 99% of the pharmaceuticals. We recorded even better results for the monoaromatics decontamination except for one month, when we encountered some technical problems with the aeration pump. This demonstrated the necessity of using the aeration step.

The effects of tree species, parent material (substrate), and faunal bioturbation on carbon sequestration and chemical and microbial properties in soil were studied at three post-mining sites (Piaseczno, Szczakowa, and Belchatow) in Poland that were reforested with pine, birch, oak, and alder. The samples were taken from the 0–5-cm mineral soil horizons beneath the litter layer. The samples were analyzed for pH, organic C and total N content, texture and based exchange cations. Microbial analyses included determination of ergosterol and phospholipid fatty acid (PLFA) profiles. Soil thin section was done to described faunal activity by the percentage of the soil volume occupied by earthworm casts or macrofaunal excrements. Substrate quality varied considerably among the sites; soil pH ranged from 4.0 to 6.4, and clay content ranged from 1 to 16%. The C:N ratio and other soil properties depended more on the specific combination of tree species and substrate than on tree species or substrate alone. Carbon content and C stock were positively correlated with bioturbation caused by soil macrofauna. Bioturbation was positively correlated with soil pH and the content of basic cations. In contrast, C stock was negatively correlated with the fungal to bacterial ratio (F:B ratio). Bioturbation was also positively correlated with total microbial biomass and negatively correlated with F:B ratio. Microbial biomass was positively correlated with N content and pH, both of which were negatively correlated F:B ratio.

These experiments were performed to verify the potential ways of treating pig farm effluents using aeration, struvite precipitation and filtration. MgCl2 brine was added as a source of magnesium for struvite precipitation. Following aeration, precipitated struvite was separated from the effluent by filtration through a compressed straw filter. The filter plus struvite can be composted to yield struvite-enriched compost. A series of 5 batch pilot-scale experiments (effluent volumes from 200–400 l) was carried out and laboratory tests on the same effluent were performed to validate the pilot-scale results. Following 24 hours of aeration the pH increased to from 8.5 to 9, providing good conditions for struvite precipitation. Filtration proved to be efficient for separating precipitated struvite and total suspended solids. The efficiency of orthophosphate phosphorus removal in the pilot system varied from 63 to 96%, ammonia nitrogen removal varied from 22 to 79%, but magnesium removal efficiency was low due to the high natural Mg concentration, suggesting that the addition of Mg might not be necessary. Chemical oxidation demand declined significantly as a result of very high bacterial activity and the treated effluent no longer had an unpleasant smell.

Titanium dioxide nanoparticles (TiO2 NPs) are manufactured worldwide. Once they arrive in the soil environment, they can endanger living organisms. Hence, monitoring and assessing the effects of these nanoparticles is required. We focus on the Eisenia andrei earthworm immune cells exposed to sublethal concentrations of TiO2 NPs (1, 10, and 100 &micro, g/mL) for 2, 6, and 24 h. TiO2 NPs at all concentrations did not affect cell viability. Further, TiO2 NPs did not cause changes in reactive oxygen species (ROS) production, malondialdehyde (MDA) production, and phagocytic activity. Similarly, they did not elicit DNA damage. Overall, we did not detect any toxic effects of TiO2 NPs at the cellular level. At the gene expression level, slight changes were detected. Metallothionein, fetidin/lysenin, lumbricin and MEK kinase I were upregulated in coelomocytes after exposure to 10 &micro, g/mL TiO2 NPs for 6 h. Antioxidant enzyme expression was similar in exposed and control cells. TiO2 NPs were detected on coelomocyte membranes. However, our results do not show any strong effects of these nanoparticles on coelomocytes at both the cellular and molecular levels.

The present report describes a 13month pilot remediation study that consists of a combination of Cr(VI) (4.4 to 57mg/l) geofixation and dechlorination of chlorinated ethenes (400 to 6526μg/l), achieved by the sequential use of nanoscale zerovalent iron (nZVI) particles and in situ biotic reduction supported by whey injection. The remediation process was monitored using numerous techniques, including physical-chemical analyses and molecular biology approaches which enabled both the characterization of the mechanisms involved in pollutant transformation and the description of the overall background processes of the treatment. The results revealed that nZVI was efficient toward Cr(VI) by itself and completely removed it from the groundwater (LOQ 0.05mg/l) and the subsequent application of whey resulted in a high removal of chlorinated ethenes (97 to 99%). The persistence of the reducing conditions, even after the depletion of the organic substrates, indicated a complementarity between nZVI and the whey phases in the combined technology as the subsequent application of whey phase partially assisted the microbial regeneration of the spent nZVI by promoting its reduction into Fe(II), which further supported remediation conditions at the site. Illumina sequencing and the detection of functional vcrA and bvcA genes documented a development in the reducing microbes (iron-reducing, sulfate-reducing and chlororespiring bacteria) that benefited under the conditions of the site and that was probably responsible for the high dechlorination and/or Cr(VI) reduction. The results of this study demonstrate the feasibility and high efficiency of the combined nano-biotechnological approach of nZVI and whey application in-situ for the removal of Cr(VI) and chlorinated ethenes from the groundwater of the contaminated site.

Oxidative stress induced by zero-valent iron nanoparticles (nZVIs) was used to improve lipid accumulation in various oleaginous and non-oleginous yeasts-Candida sp., Kluyveromyces polysporus, Rhodotorula glutinis, Saccharomyces cerevisiae, Torulospora delbrueckii, Trichosporon cutaneum, and Yarrowia lipolytica. The highest lipid yields occurred at 9-13 mg/L nZVIs. Gas chromatography-mass spectrometry was used for the quantitative and qualitative analysis of the fatty acids. It showed an increasing abundance of polyunsaturated fatty acids, especially essential linoleic acid, in the presence of nZVIs. Our results suggest that nZVIs can be used to improve not only lipid production by oleaginous microorganisms but also the nutritional value of biosynthesized unsaturated fatty acids.

To understand why excrements of soil macrofauna often decompose more slowly than leaf litter, we fed Bibio marci larvae the litter of tree species differing in litter quality ( Alnus glutinosa , Salix caprea , and Quercus robur ) and then measured respiration induced by litter and excrements. We also measured respiration induced by the same litter artificially modified to mimic faunal effects; the litter was modified by grinding, grinding with alkalinization to pH = 11, grinding with coating by kaolinite, and grinding with both alkalinization and coating. Decomposition of excrements tended to be slower for willow and was significantly slower for oak and alder than for the corresponding litter. With oak, decomposition was slower for all artificially modified litter than for non-modified litter. The reduction in the decomposition was similar for excrements and for alder and willow litter that was ground, coated, and alkalinized. In alder, a similar reduction was found in ground and alkalinized litter. 13 C NMR indicated that gut passage increases aliphatic components and decreases polysaccharides. Pyrolysis indicated that gut passage increases the ratio of guaiacyl to hydroxymethyl derivatives in lignin. Our findings indicate that the decreased decomposition rate of excrements might result from the removal of easily available polysaccharides, the increase in aliphatic components, an increase in the resistant components of lignin, the accumulation of microbial cell walls, and the binding of nitrogen into complexes with aromatic components. Several of these mechanisms are supported or determined by litter alkalinization during gut passage.

The paper describes a pilot remediation test combining two Cr(VI) geofixation methods - chemical reduction by nanoscale zero-valent iron (nZVI) and subsequent biotic reduction supported by whey. Combination of the methods exploited the advantages of both - a rapid decrease in Cr(VI) concentrations by nZVI, which prevented further spreading of the contamination and facilitated subsequent use of the cheaper biological method. Successive application of whey as an organic substrate to promote biotic reduction of Cr(VI) after application of nZVI resulted in a further and long-term decrease in the Cr(VI) contents in the groundwater. The effect of biotic reduction was observed even in a monitoring well located at a distance of 22 m from the substrate injection wells after 10 months. The results indicated a reciprocal effect of both the phases - nZVI oxidized to Fe(III) during the abiotic phase was microbially reduced back to Fe(II) and acted as a reducing agent for Cr(VI) even when the microbial density was already low due to the consumed substrate. Community analysis with pyrosequencing of the 16S rRNA genes further confirmed partial recycling of nZVI in the form of Fe(II), where the results showed that the Cr(VI) reducing process was mediated mainly by iron-reducing and sulfate-reducing bacteria.

Wood ant nests are hotspots of nutrients and microbial activity in nutrient-limited coniferous forest ecosystems, as ants accumulate honeydew and nutrients in their nests due to foraging and building activities. In this study we carried out a microcosm experiment focussing on the role of bacteria and protozoa on carbon and nitrogen turnover in nutrient-rich and nutrient-poor litter materials. Two types of litter material, (i) ant nest material or (ii) surrounding forest floor material were sterilized and inoculated either with bacteria alone (B treatment) or with bacteria and protozoa in combination (BP treatment). The litter materials were subsequently incubated in laboratory microcosms for 21 days. Respiration of the microcosms was measured during the whole incubation period and leachates were sampled every week and analysed for ammonium and nitrate. Our results showed lower ammonium leaching and increased respiration in the BP treatment, which could be explained by higher microbial biomass in this treatment. The negative effect of protozoa on ammonium leaching was independent of the type of litter material suggesting that available carbon in nest material supported fixation of nitrogen in the bacterial biomass. Our data show that protozoan grazing can play a critical role in retaining nitrogen in ant nests by increasing microbial activity and biomass, and thereby preventing nitrogen leaching.

Cultivation in Zehnder medium containing 5.1 mg L−1 zero-valent iron nanoparticles (nZVI) boosted the growth of the green algae Desmodesmus subspicatus, Dunaliella salina, Parachlorella kessleri and Raphidocelis subcapitata and the eustigmatophycean algae Nannochloropsis limnetica and Trachydiscus minutus. In the cyanobacterium Arthrospira maxima, growth stimulation occurred at 1.7–5.1 mg L−1 nZVI. In all studied microorganisms, 5.1 mg L−1 nZVI strongly enhanced lipid accumulation, decreased the content of saturated and monounsaturated fatty acids with the exception of palmitoleic acid and increased the content of polyunsaturated fatty acids in cells. The nZVI particles may provide a suitable source of iron causing increased cell growth and induce metabolic changes resulting in higher lipid production and changes in fatty acid (FA) composition. Altered lipid synthesis may reflect the oxidative action of nZVI. Further research may contribute to optimizing the economical production of oils from oleaginous microorganisms and help clarify the mechanism of nZVI action.

Chlorobenzoic acids (CBAs) are the major metabolite of aerobic bacterial degradation of polychlorinated biphenyls (PCBs). A rapid and simple simultaneous derivatisation method has been developed for gas chromatography-mass spectrometry determination in historically PCB-contaminated soils for 15 isomers of mono-, di-, tri-, tetra-, and pentachlorobenzoic acids in CBA mixtures. Two derivatisation agents (diazomethane and methyl chloroformate) and various conditions were evaluated (temperature, time, solvents, catalysts) in terms of efficiency. The optimised derivatisation method with diazomethane and 1% methanol running 1 hour at 5°C was used for derivatisation of extracts of soils and river sediment from historically PCB-contaminated sites; the extracts were prepared using accelerated solvent extraction by a previously described method. Methylated CBAs were separated by gas chromatography using a system with two different common columns, DB-5 and DB-200, in series-coupled (tandem) arrangement and detected ...

Flumequine, a fluoroquinolone antibiotic, is applied preferably in veterinary medicine, for stock breeding and treatment of aquacultures. Formation of drug resistance is a matter of general concern when antibiotics such as flumquine occur in the environment. Thus, biodegradation of flumequine in solution was investigated using five different ligninolytic fungi. Irpex lacteus, Dichomitus squalens, and Trametes versicolor proved most efficient and transformed more than 90% of flumequine within 6 or even 3 days. Panus tigrinus and Pleurotus ostreatus required up to 14 days to remove >90% of flumequine. Analyses of the metabolites by liquid chromatography-mass spectrometry suggest different transformation pathways for the different fungal strains. Structure proposals were elaborated for 8 metabolites. 7-Hydroxy-flumequine and flumequine ethyl ester were identified as common metabolites produced by all ligninolytic fungi. The largest variety of metabolites was formed by D. squalens. Residual antibacterial activity of the metabolite mixtures was tested using gram-positive and gram-negative bacteria. While for the less efficient P. tigrinus and P. ostreatus cultures the antibacterial activities corresponded to the residual concentrations of flumequine, a remarkable antibacterial activity remained in the D. squalens cultures although flumequine was transformed to more than 90%. Obviously, antibacterially active transformation products were formed by this fungal strain.

LC with atmospheric pressure chemical ionization (ACPI) MS with RP and chiral phase was used for separation of triacylglycerols (TAGs) from yeasts of the genera Candida, Kluyveromyces, Rhodotorula, Saccharomyces, Torulospora, Trichosporon, and Yarrowia. Chiral LC-APCI-MS is based on using two columns in series packed with a 3,5-dimethylphenyl carbamate modified β-cyclodextrin chiral phase. All regioisomers and enantiomers of TAGs containing one to five double bonds were separated. Molecular species of TAGs, i.e. regioisomers and enantiomers, were identified and quantified by MS/MS. Among the 94 identified TAGs, the most abundant were triolein, oleopalmitoleoolein, and dipalmitoleoolein. In strains producing palmitoleic acid in amounts >25% of total fatty acids (FAs), this acid, or unsaturated FA is bound in sn-1. In strains containing palmitoleic acid at 10-25% total FAs this acid is mainly bound in sn-3, saturated FA being bound in sn-1. Strains containing

The contents of fungal biomass markers were analysed in the fruit bodies of dominant basidiomycetes from an ectomycorrhiza-dominated coniferous forest, and used to estimate the fungal biomass content in the litter and soil. The content of ergosterol (3.8 ± 2.0 mg g−1 dry fungal biomass) and the phospholipid fatty acid 18:2ω6,9 (11.6 ± 4.3 mg g−1) showed less variation than the internal transcribed spacer (ITS) copy numbers (375 ± 294 × 109 copies g−1). A high level of variation in the ITS copy numbers (per ng DNA) was also found among fungal taxa. The content of fungal biomass in the litter and soil, calculated using the mean contents, varied between 0.66 and 6.24 mg g−1 fungal biomass in the litter, and 0.22 and 0.68 mg g−1 in the soil. The ratio of fungal biomass in the litter to that in the soil varied greatly among the markers. The estimates of fungal biomass obtained with different biomarkers are not exactly comparable, and caution should be used when analysing taxon abundance using PCR amplification of fungal rDNA.

The white rot fungus Pleurotus ostreatus HK 35, which is also an edible industrial mushroom commonly cultivated in farms, was tested in the degradation of typical representatives of endocrine disrupters (EDCs; bisphenol A, estrone, 17β-estradiol, estriol, 17α-ethinylestradiol, triclosan and 4-n-nonylphenol); its degradation efficiency under model laboratory conditions was greater than 90% within 12 days and better than that of another published strain P. ostreatus 3004. A spent mushroom substrate from a local farm was tested for its applicability in various batch and trickle-bed reactors in degrading EDCs in model fortified and real communal wastewater. The reactors were tested under various regimes including a pilot-scale trickle-bed reactor, which was finally tested at a wastewater treatment plant. The result revealed that the spent substrate is an efficient biodegradation agent, where the fungus was usually able to remove about 95% of EDCs together with suppression of the estrogenic activity of the sample. The results showed the fungus was able to operate in the presence of bacterial microflora in wastewater without any substantial negative effects on the degradation abilities. Finally, a pilot-scale trickle-bed reactor was installed in a wastewater treatment plant and successfully operated for 10days, where the bioreactor was able to remove more than 76% of EDCs present in the wastewater.

Industrial particulate matter (PM) air pollution exposing nearby residential areas forms several European air pollution hot-spots. One of these hot-spot is the residential district of Ostrava Radvanice-Bartovice with frequent exceedances for PM and benzo[a]pyrene B[a]P, a carcinogenic polycyclic aromatic hydrocarbon (PAH) of MW228 amu. Such PAHs are highly bonded to the ultrafine particles (UFPs), the smallest PM size fraction, which deposits most efficiently in the alveolar region of human lungs. Airborne measurements identified UFP point sources in the adjacent metallurgical complex and mapped limited horizontal and vertical dispersion of industrial plumes enriched with UFPs (3.2 × 10(5)cm(-3)). The plumes, episodes of simultaneous peaks of UFPs (1.4 × 10(5)cm(-3)), SO2 (88.2 ppb), and CO (11.3 ppm), were recorded on the ground downwind in the residential district when wind speeds1 ms(-1). In the plumes, UFPs were mostly 19-44 nm in diameter, enriched with PAHs/B[a]P up to 43.8/3.5 mg·g(-1). Electron microscopy showed that these plume UFPs were mostly agglomerates of spherules of 30-50 nm in diameter. These source impact measurements, that combine airborne and ground-level measurements, are applicable to clearly identify specific industrial air pollution sources and provide information to assess their possible impact to human health in similar hot-spots worldwide.

The possibility of using fungi and fungal enzymes in the remediation of persistent organopullutants is a subject of keen interest to both microbiologists and scientists working in the auspices of the environmental sciences. This chapter reviews the proven ability of several saprotrophic fungi with distinct physiological and biochemical features to degrade and mineralize a wide range of organic and xenobiotic pollutants, including oil-derived products, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, dioxins and furans, pesticides, herbicides, nitroaromatic explosives and pharmaceuticals. Finally, insights into this complex subject are presented, based on current information from pilot- and field-scale trials, as to why fungi should be considered as suitable candidates to design effective bioremediation technologies for persistent organic pollutants and other emerging organic micropollutants.

After the phase-out of two commercial mixtures of brominated flame retardants, an increasing number of alternative flame retardants have been introduced in commercial applications. None of them, however, has been thoroughly tested for its hormonal activity. We used two yeast reporter-gene assays to determine the potential of eleven compounds to interfere with estrogenic and androgenic pathways. Our data demonstrate the ability of 2,4,6-tribromophenol to lower the transcriptional activity of human estrogen and androgen receptors. A nominal IC 50 value of 14.1 μM for anti-estrogenic and 3.9 μM for anti-androgenic activity was obtained using the luciferase reporter. An IC 50 value of 9.2 μM was calculated for the anti-estrogenic activity measured by the β-galactosidase assay. Of the tested chemicals, this study highlights the endocrine disrupting effects of 2,4,6-tribromophenol whose occurrence in the environment should be monitored.

Chemical composition of litter has previously been reported to affect in situ decomposition. To identify its effects on a single species level, the saprotrophic basidiomycete Hypholoma fasciculare was grown on 11 types of litter with variable chemical composition (N content of 3.4–28.9 mg g−1), and the mass loss of litter and lignin, production of extracellular enzymes and fungal biomass were followed. After 12 weeks, mass loss ranged from 16 % to 34 %. During early decomposition stages, litter mass loss, fungal biomass production (estimated by ergosterol content) as well as fungal substrate use efficiency all increased with increasing initial N content of the litter. The initial litter decomposition rate was significantly positively correlated with the activities of arylsulfatase, cellobiohydrolase, endoxylanase and phosphatase. Contrary to expectations, the lignin content did not affect litter mass loss, when covariation with N content was accounted for. The ratio of lignin loss to total mass loss depended on the litter type and did not reflect the activities of ligninolytic enzymes.

We investigated the abilities of several perspective ligninolytic fungal strains to degrade 12 mono-, di- and trichloro representatives of chlorobenzoic acids (CBAs) under model liquid conditions and in contaminated soil. Attention was also paid to toxicity changes during the degradation, estimated using two luminescent assay variations with Vibrio fischeri. The results show that almost all the fungi were able to efficiently degrade CBAs in liquid media, where Irpex lacteus, Pycnoporus cinnabarinus and Dichomitus squalens appeared to be the most effective in the main factors: degradation and toxicity removal. Analysis of the degradation products revealed that methoxy and hydroxy derivatives were produced together with reduced forms of the original acids. The findings suggest that probably more than one mechanism is involved in the process. Generally, the tested fungal strains were able to degrade CBAs in soil in the 85-99% range within 60 days. Analysis of ergosterol showed that active colonization is an important factor for degradation of CBAs by fungi. The most efficient strains in terms of degradation were I. lacteus, Pleurotus ostreatus, Bjerkandera adusta in soil, which were also able to actively colonize the soil. However, in contrast to P. ostreatus and I. lacteus, B. adusta was not able to significantly reduce the measured toxicity.

The common grass Calamagrostis epigeions produces a large amount of dead biomass, which remain above the soil surface for many months. In this study, we determined how exposure of dead biomass above the soil affects its subsequent decomposition in soil. Collected dead standing biomass was divided in two parts, the first one (initial litter) was stored in a dark, dry place. The other part was placed in litterbags in the field. The litterbags were located in soil, on the soil surface, or hanging in the air without contact with soil but exposed to the sun and rain. After 1 year of field exposure, litter mass loss and C and N content were measured, and changes in litter chemistry were explored using NMR and thermochemolysis-GC-MS. The potential decomposability of the litter was quantified by burying the litter from the litterbags and the initial litter in soil microcosms and measuring soil respiration. Soil respiration was greater with litter that had been hanging in air than with all other kinds of litter. These finding could not be explained by changes in litter mass or C:N ratio. NMR indicated a decrease in polysaccharides relative to lignin in litter that was buried in soil but not in litter that was placed on soil surface or that was hanging in the air. Thermochemolysis indicated that the syringyl units of the litter lignin were decomposed when the litter was exposed to light. We postulate that photochemical decay of lignin increase decomposability of dead standing biomass.

The links among the changes in litter chemistry, the activity of extracellular enzymes and the microbial community composition were observed in Quercus petraea litter. Three phases of decomposition could be distinguished. In the early 4-month stage, with high activities of β-glucosidase, β-xylosidase and cellobiohydrolase, 16.4% of litter was decomposed. Hemicelluloses were rapidly removed while cellulose and lignin degradation was slow. In months 4-12, with high endocellulase and endoxylanase activities, decomposition of cellulose prevailed and 31.8% of litter mass was lost. After the third phase of decomposition until month 24 with high activity of ligninolytic enzymes, the litter mass loss reached 67.9%. After 2 years of decay, cellulose decomposition was almost complete and most of the remaining polysaccharides were in the form of hemicelluloses. Fungi largely dominated over bacteria as leaf endophytes and also in the litter immediately before contact with soil, and this fungal dominance lasted until month 4. Bacterial biomass (measured as phospholipid fatty acid content) in litter increased with time but also changed qualitatively, showing an increasing number of Actinobacteria. This paper shows that the dynamics of decomposition of individual litter components changes with time in accordance with the changes in the microbial community composition and its production of extracellular enzymes.

The small-scale distribution of activities of extracellular laccase, Mn-peroxidase, endoglucanase, cellobiohydrolase, β-glucosidase, endoxylanase, β-xylosidase, chitinase, and acid phosphatase were studied in the litter (L) and organic (H) horizons of Quercus petraea forest soil and related to the distribution of microbial biomass. Geostatistical analysis showed that the spatial autocorrelation of the enzyme activities and soil microbial biomass measured as phospholipid fatty acids (PLFA) and ergosterol content occurred at similar scales, typically in the range of tens of centimeters. The size of the spatial structures differed between the L and H horizons; for most of the studied enzymatic processes, litter exhibited a higher spatial variability (smaller autocorrelation distances). The distribution of several enzymes, including laccase, Mn-peroxidase, and some hydrolases, reflected the distribution of fungal biomass. Polysaccharide hydrolases exhibited similar spatial distribution patterns in the L horizon, and their activity coincided with a high fungal/bacterial biomass ratio.

The short-term response of the resident soil bacterial and fungal communities to the addition of 5% (w/w) of either dry olive mill residue (DOR), DOR treated with Phlebia sp. (PTDOR) or DOR previously extracted with water (WEDOR) was investigated. As opposed to bacteria, the diversity of fungi increased upon the amendments as assessed by denaturing gradient gel electrophoresis of 18S rDNA. Over the first 30 days, phospholipid fatty acids analyses indicated a gradual decrease in the relative abundances of Gram+ bacteria (from 44.8% to 37.9%) and a concomitant increase of Gram- bacteria (from 37.3% to 51.2%) in DOR-amended soil. A considerable increase in the fungal/bacterial ratio was observed after 7 days in DOR, WEDOR and PTDOR-amended soils with respect to the control (0.316, 0.165 and 0.265, respectively, vs. 0.011). The overall microbial activity was stimulated by the amendments as indicated by the higher activity levels of both dehydrogenase and fluorescein diacetate hydrolase. These results indicate that DOR at the application level examined is not toxic on soil microorganisms. L'articolo é disponibile sul sito dell'editore: http://www.sciencedirect.com

Investigations of environmental pollution by endocrine-disrupting chemicals are now in progress. Up to now, several in vitro bioassays have been developed for evaluation of the endocrine disruptive activity; however, there is still a lack of comparative studies of their sensitivity. In this work comparison of the estrogen screening assay based on β-galactosidase expression and a bioluminescent estrogen screen revealed differences in the sensitivity and specificity of the two tests. With the β-galactosidase screen a slight estrogen-like activity of Delor 103, a commercial mixture of PCB congeners, and a fungicide triclosan was measured whereas no activity was detected using the bioluminescent assay. A bioluminescent androgen test negated previously suggested androgenic potential of triclosan. Further, this work demonstrates the androgenic activity of Delor 103, with an EC 50 value of 2.29 × 10 − 2 mg/L. On the other hand, chlorobenzoic acids (CBAs), representing potential PCB degradation metabolites, exhibited no androgenic activity but were slightly estrogenic. Their estrogenicity varied with their chemical structure, with 2,3-CBA, 2,3,6-CBA, 2,4,6-CBA and monochlorinated compounds exhibiting the highest activity. Thus the results indicated possible transitions of the hormonal activity of PCBs during bacterial degradation.

White-rot fungi that are efficient lignin degraders responsible for its turnover in nature have appeared twice in the center of biotechnological research - first, when the lignin degradation process started being systematically investigated and major enzyme activities and mechanisms involved were described, and second, when the huge remediation potential of these organisms was established. Originally, Phanerochaete chrysosporium became a model organism, characterized by a secondary metabolism regulatory pattern triggered by nutrient (mostly nitrogen) limitation. Last decade brought evidence of more varied regulatory patterns in white-rot fungi when ligninolytic enzymes were also abundantly synthesized under conditions of nitrogen sufficiency. Gradually, research was focused on other species, among them Irpex lacteus showing a remarkable pollutant toxicity resistance and biodegradation efficiency. Systematic research has built up knowledge of biochemistry and biotechnological applicability of this fungus, stressing the need to critically summarize and estimate these scattered data. The review attempts to evaluate the information on I. lacteus focusing on various enzyme activities and bioremediation of organopollutants in water and soil environments, with the aim of mediating this knowledge to a broader microbiological audience.

Activity and production of extracellular enzymes by saprotrophic litter-decomposing basidiomycetes Hypholoma fasciculare and Rhodocollybia butyracea was studied in microcosms with reconstructed L, O and Ah horizons of a soil profile of Quercus petraea forest soil. Both H. fasciculare and R. butyracea colonized the L layer of microcosms rapidly, while the colonization of O layer was slower. The Ah layer was substantially colonized only by R. butyracea. Enzyme activities in the soil microcosms decreased from the L layer > O layer > Ah layer and activities in microcosms inoculated with the fungi were quite similar to each other. Compared to control, the most apparent was the increase of ligninolytic enzyme activities. Laccase activities in H. fasciculare and R. butyracea-colonized L layers were 3-fold compared to control and the activity maxima of Mn-peroxidase in fungus-colonized O layers were 2–3-fold and in the L layers up to 40-fold compared to controls. Activities of cellulolytic enzymes, chitinase and acidic phosphatase in both fungal treatments were higher in the L layer on weeks 2–6 while the activity of alkaline phosphatase did not show differences between fungus-colonized and control treatments. Both fungi decreased fungal CFU in the L layer but significantly increased the counts in the O layer. Both fungi also increased bacterial CFU in the O layer, R. butyracea more than H. fasciculare. The analysis of fungal and bacterial biomass based on ergosterol content and PLFA analysis showed a sharp decrease from L to Ah layer, but did not show significant differences among treatments.

In this work we report on possible utilisation of sulphonated phthalocyanines as efficient oxidation catalysts for the removal of various traces of chlorinated compounds from an aquatic environment. Photocatalytic oxidations were carried out with visible and ultraviolet light in agreement with location of their distinctive absorption bands in both these regions. The reaction rate of decomposition of the substrate was measured as a function of pH. Special attention was paid to describe aggregation of the photocatalyst resulting in significant decreasing of the photooxidation activity. Suppression of this undesirable phenomenon by addition of some alcohol to the reaction mixture was studied in detail. Photocatalytic efficiency was verified according to calculated quantum yields.

Due to the production of lignocellulose-degrading enzymes, saprotrophic basidiomycetes can significantly contribute to the turnover of soil organic matter. The production of lignin- and polysaccharide-degrading enzymes and changes of the chemical composition of litter were studied with three isolates from a Quercus petraea forest. These isolates were capable of fresh litter degradation and were identified as Gymnopus sp., Hypholoma fasciculare and Rhodocollybia butyracea. Within 12 weeks of incubation, H. fasciculare decomposed 23%, R. butyracea 32% and Gymnopus sp. 38% of the substrate dry mass. All fungi produced laccase and Mn-peroxidase (MnP) and none of them produced lignin peroxidase or other Mn-independent peroxidases. There was a clear distinction in the enzyme production pattern between R. butyracea or H. fasciculare compared to Gymnopus sp. The two former species caused the fastest mass loss during the initial phase of litter degradation, accompanied by the temporary production of laccase (and MnP in H. fasciculare) and also high production of hydrolytic enzymes that later decreased. In contrast, Gymnopus sp. showed a stable rate of litter mass loss over the whole incubation period with a later onset of ligninolytic enzyme production and a longer lasting production of both lignin and cellulose-degrading enzymes. The activity of endo-cleaving polysaccharide hydrolases in this fungus was relatively low but it produced the most cellobiose hydrolase. All fungi decreased the C/N ratio of the litter from 24 to 15–19 and Gymnopus sp. also caused a substantial decrease in the lignin content. Analytical pyrolysis mass spectrometry of litter decomposed by this fungus showed changes in the litter composition similar to those caused by white-rot fungi during wood decay. These changes were less pronounced in the case of H. fasciculare and R. butyracea. All fungi also changed the mean masses of humic acid and fulvic acid fractions isolated from degraded litter. The humic acid fraction after degradation by all three fungi contained more lignin and less carbohydrates. Compared to the decomposition by saprotrophic basidiomycetes, litter degradation in situ on the site of fungal isolation resulted in the relative enrichment of lignin and differences in lignin composition revealed by analytical pyrolysis. It can most probably be explained by the participation of non-basidiomycetous fungi and bacteria during natural litter decomposition.

Titania nanostructured particles were produced by the sol–gel method in the reverse micelle environment treated thermally and by various extraction steps including supercritical carbon dioxide, subcritical water and their combinations. Thin films comprised of the organized nanoparticles were tested in photoelectrochemical and photocatalytic experiments. The former were configured for the open circuit potential measurements and evaluation of polarization curves and the corresponding photocurrents. Photocatalytic activities of the layered films were assessed by following decomposition of the methyl ester of stearic acid. Attention was also paid to evaluation of the extent of the surface wettability of the layers. The effect of content of residual surface carbon, extent of hydrophilic properties and presence of anatase structure were identified as essential parameters responsible for the enhanced photoactivity of the tested layers. On the other hand also layers treated without any thermal steps revealed certain level of photoactivity that might be of special importance in some specific applications.

Cultures of the ligninolytic fungus Irpex lacteus incubated in a nutrient liquid medium degraded more than 70% of the initially applied benz[a]anthracene within 14 days. At the first step of metabolization, benz[a]anthracene was transformed via a typical pathway of ligninolytic fungi to benz[a]anthracene-7,12-dione (BaAQ). The product was further transformed by at least two ways, whereas one is complied with the anthracene metabolic pathway of I. lacteus. Benz[a]anthracene-7,12-dione was degraded to 1,2-naphthalenedicarboxylic acid and phthalic acid that was followed with production of 2-hydroxymethyl benzoic acid or monomethyl and dimethylesters of phthalic acid. Another degradation product of BaAQ was identified as 1-tetralone. Its transformation via 1,4-naphthalenedione, 1,4-naphthalenediol and 1,2,3,4-tetrahydro-1-hydroxynaphthalene resulted again in phthalic acid. None of the intermediates were identified as dead-end metabolites. Metabolites produced by ring cleavage of benz[a]anthracene using the ligninolytic fungus are firstly presented in this work.

Titania (TiO 2 ) nanostructured particles were produced by the sol–gel method in the reverse micelle environment with a focus on the complete “low temperature methodology.” This methodology was based on utilisation of specially designed extraction methods with subcritical water, supercritical carbon dioxide and their combination to limit the content of organics and also to establish the particles' enhanced photoactivity without recourse to high temperatures. Their characteristic physical properties were described and photoactivity tests then performed. The catalytic tests were carried out in gas phase with acetone and with a low intensity source of UV. It was clearly shown that photoactive titania thin layers could be produced at low temperature, however, with activity significantly lower than observed for analogous sol–gel layers finally treated thermally. Nevertheless the designed methodology could be referred to as the process adaptable for plastic substrates and yielding photoactive thin films.

Methyl tert-butyl ether (MTBE) is a synthetic compound that is used as a technological solution to problems created by air pollution from vehicle emissions. An important source of MTBE in the environment is leakage from underground storage tanks at gasoline stations or accidents during gasoline transport. The aim of this study was to evaluate the risk of MTBE leakage for the environment using the Microtox (Vibrio fischeri) toxicity test, Lactuca sativa seed germination test, and Ames bacterial mutagenicity test with Salmonella typhimurium his(-) strains TA98, TA100, YG1041, and YG1042, using both standard plate and preincubation protocols. The result of Microtox expressed as EC(50) was 33 mg (MTBE)/L. The effect of all tested MTBE concentration (0.05, 0.50, and 1.00% v/v) on Lactuca sativa roots elongation was negative and proved its toxicity. The highest tested concentration of MTBE that could be tested in Ames test was 3 mg (MTBE)/plate, because of cytotoxicity. No mutagenic response was observed at this or lower concentrations in any of the four strains used.

Photocatalytic oxidation of cyclopentene was performed over a series of structure different titanium(IV) oxide catalysts. The reaction was carried out with a special attention to limit the extent of the cyclic alkene total decomposition to water and carbon dioxide. It was shown that variable surface catalytic structures of titania acting together with active surface species (e.g., surface hydrogen peroxide, hydroxyl radicals, singlet oxygen) may significantly affect the course of the partial photooxidation. Reactions were carried out in liquid phase, isothermally and at atmospheric pressure with oxygen in the quartz reactor fitted with a source of UV. The catalysts’ structure dependent selectivity profiles were compared with similar kinetic data obtained previously in partial photocatalytic oxidation of cyclohexene.