Dynamics of microbial communities during biotransformation of nitrofurantoin.

The purpose of this research was to investigate the biodegradation of nitrofurantoin (NFT), a typical nitrofuran antibiotic of potential carcinogenic properties, by two microbial communities derived from distinct environmental niches - mountain stream (NW) and seaport water (SS). The collected environmental samples represent the reserve of the protected area with no human intervention and the contaminated area that concentrates intense human activities. The structure, composition, and diversity of the communities were analyzed at three timepoints during NFT biodegradation. Comamonadaceae (43.2%) and Pseudomonadaceae (19.6%) were the most abundant families in the initial NW sample. The top families in the initial SS sample included Aeromonadaceae (31.4%) and Vibrionaceae (25.3%). The proportion of the most abundant families in both consortia was remarkably reduced in all samples treated with NFT. The biodiversity significantly increased in both consortia treated with NFT suggesting that NFT significantly alters community structure in the aquatic systems. In this study, NFT removal efficiency and transformation products were also studied. The biodegradation rate decreased with the increasing initial NFT concentration. Biodegradation followed similar pathways for both consortia and led to the formation of transformation products: 1-aminohydantoin, semicarbazide (SEM), and hydrazine (HYD). SEM and HYD were detected for the first time as NFT biotransformation products. This study demonstrates that the structure of the microbial community may be directly correlated with the presence of NFT. Enchanced biodiversity of the microbial community does not have to be correlated with increase in functional capacity, such as the ability to biodegradation because higher biodiversity corresponded to lower biodegradation. Our findings provide new insights into the effect of NFT contamination on aquatic microbiomes. The study also increases our understanding of the environmental impact of nitrofuran residues and their biodegradation.

Application of phosphonium deep eutectic solvents as extractants in ultrasound-assisted dispersive liquid-liquid microextraction for preconcentration of trace amounts of herbicides in drainage ditches waters.

In this study, an efficient preconcentration method was presented that is based on dispersive liquid-liquid microextraction taking the advantage of newly synthesized phosphonium deep eutectic solvents used as extractants and ultrasound probe as a dispersing agent. The extracts obtained were analyzed by high-performance liquid chromatography. To optimize the five most important factors for the microextraction procedure a central composite design plan was used. Under optimal conditions (140 µl of extractant, 60 mg of NaCl, pH = 2.0, 120 s of extraction time with ultrasound probe as the dispersing agent, 16 min of centrifugation for phase separation), the proposed method allowed to achieve good precision with RSD between 3.2% and 9.7% at 1.0, 5.0 and 40.0 ng ml levels. The preconcentration factors were equal to 42, 39, and 41, and the limits of detection 0.128, 0.103, and 0.135 ng/ml for dicamba, 2-methyl-4-chlorophenoxyacetic acid, and 2-methyl-4-chlorophenoxypropionic acid, respectively. The proposed method was successfully applied for the determination of chlorophenoxy acid herbicides in water samples from drainage ditches with a good recovery in the range of 70%-93%.

Development of novel thin-film solid-phase microextraction materials based on deep eutectic solvents for preconcentration of trace amounts of parabens in surface waters.

A green and sensitive thin-film solid-phase microextraction method based on deep eutectic solvent was developed that enables simultaneous isolation, preconcentration, and determination of parabens in surface waters. Six new deep eutectic solvents were synthesized and used directly to prepare thin-film coatings on a stainless steel mesh support. Among the compounds obtained, the highest efficiency in the extraction of parabens was found for a material consisting of trihexyltetradecylphosphonium chloride and n-docosanol in a molar ratio of 1:2. For the proposed method, parameters affecting the extraction efficiency of parabens, such as the coating material, the desorption solvent, the volume of the sample, the pH of the sample, the extraction and desorption time, and the salting-out effect, were optimized. Under optimal conditions, the proposed method allowed us to achieve good precision between 3.6 and 6.5% and recovery ranging from 68.1 to 91.4%. The limits of detection range from 0.018 to 0.055 ng/mL.

Variation in the Content of Bioactive Compounds in Infusions Prepared from Different Parts of Wild Polish Stinging Nettle (Urtica dioica L.).

Nettle is a common plant that offers many health benefits and is grown all over the world. The content of active compounds in roots, stems, and leaves was determined based on the extraction procedure optimized using the Central Composite Design. Flavonols, phenolic acids, trigonelline, nicotinamide, nicotinic acids, and short-chain organic acids were determined with the use of LC-MS/MS and capillary isotachophoresis. Trigonelline, which was not previously reported in the roots and stems of nettle, was found in all parts of the plant and considerable variations in its content were observed (2.8-108 µg g-1). Furthermore, the Principal Component Analysis taking into account more variables demonstrated differences in the content of bioactive components between roots and aerial parts of nettle.

Nitrofurazone Removal from Water Enhanced by Coupling Photocatalysis and Biodegradation.

(1) Background: Environmental contamination with antibiotics is particularly serious because the usual methods used in wastewater treatment plants turn out to be insufficient or ineffective. An interesting idea is to support natural biodegradation processes with physicochemical methods as well as with bioaugmentation with efficient microbial degraders. Hence, the aim of our study is evaluation of the effectiveness of different methods of nitrofurazone (NFZ) degradation: photolysis and photodegradation in the presence of two photocatalysts, the commercial TiO2-P25 and a self-obtained Fe3O4@SiO2/TiO2 magnetic photocatalyst. (2) Methods: The chemical nature of the photocatalysis products was investigated using a spectrometric method, and then, they were subjected to biodegradation using the strain Achromobacter xylosoxidans NFZ2. Additionally, the effects of the photodegradation products on bacterial cell surface properties and membranes were studied. (3) Results: Photocatalysis with TiO2-P25 allowed reduction of NFZ by over 90%, demonstrating that this method is twice as effective as photolysis alone. Moreover, the bacterial strain used proved to be effective in the removal of NFZ, as well as its intermediates. (4) Conclusions: The results indicated that photocatalysis alone or coupled with biodegradation with the strain A. xylosoxidans NFZ2 leads to efficient degradation and almost complete mineralization of NFZ.

Biodiversity of soil bacteria exposed to sub-lethal concentrations of phosphonium-based ionic liquids: Effects of toxicity and biodegradation.

Little is known about the effect of ionic liquids (ILs) on the structure of soil microbial communities and resulting biodiversity. Therefore, we studied the influence of six trihexyl(tetradecyl)phosphonium ILs (with either bromide or various organic anions) at sublethal concentrations on the structure of microbial community present in an urban park soil in 100-day microcosm experiments. The biodiversity decreased in all samples (Shannon's index decreased from 1.75 down to 0.74 and OTU's number decreased from 1399 down to 965) with the largest decrease observed in the microcosms spiked with ILs where biodegradation extent was higher than 80%. (i.e. [P66614][Br] and [P66614][2,4,4]). Despite this general decrease in biodiversity, which can be explained by ecotoxic effect of the ILs, the microbial community in the microcosms was enriched with Gram-negative hydrocarbon-degrading genera e.g. Sphingomonas. It is hypothesized that, in addition to toxicity, the observed decrease in biodiversity and change in the microbial community structure may be explained by the primary biodegradation of the ILs or their metabolites by the mentioned genera, which outcompeted other microorganisms unable to degrade ILs or their metabolites. Thus, the introduction of phosphonium-based ILs into soils at sub-lethal concentrations may result not only in a decrease in biodiversity due to toxic effects, but also in enrichment with ILs-degrading bacteria.

Detection of bisphenol A, cumylphenol and parabens in surface waters of Greater Poland Voivodeship.

Amounts of bisphenol A (BPA), 4-cumylphenol (CP) and 5 parabens - methylparaben (MP), ethylparaben (EP), propylparaben (PP), butylparaben (BP) and benzylparaben (BzP) in Greater Poland Voivodeship's surface waters are reported. The water samples were collected from selected 15 locations in 2015-2016 at seven different time points: in March, June, August, and October 2015 and March, June, and September 2016. MP was found in every tested sample with typical concentration at several dozen nanograms per liter and the highest level almost 1600 ng L-1 in a sample collected from the Warta River in October 2015. The other four parabens were determined at considerably lower concentrations than MP at levels not exceeding 100 ng L-1 with PP found at the highest and BzP at the lowest levels. BPA was determined at similar concentration level to parabens - between 5 ng L-1 and 95 ng L-1 and CP was found only in a limited number of samples. Noticeable seasonal changes of paraben concentrations were found showing that for these compounds the pollutant release factor dominates both the biodegradation factor and the water volume factor. These seasonal changes were not observed for BPA and CP. Out of all determined parabens only MP was found at considerably higher concentrations than BPA. However, MP's endocrine properties are much lower than those of BPA posing a lower environmental impact potential than BPA. Influence of other (more endocrine disrupting) parabens is also relatively weak in comparison to BPA due to their considerably lower concentrations in the environment.

Positive and negative aspects of green coffee consumption - antioxidant activity versus mycotoxins.

BACKGROUND: The quality of coffee depends not only on the contents of healthy compounds but also on its contamination with microorganisms that can produce mycotoxins during development, harvesting, preparation, transport and storage. RESULTS: The antioxidant activity of green coffee brews measured in this study by ABTS, DPPH and Folin-Ciocalteu assays showed that coffee extracts from Robusta beans possessed higher activity in all assays than extracts from Arabica beans. The occurrence of ochratoxin A and aflatoxins (B1, B2, G1 and G2) in green coffee beans was studied using liquid chromatography/mass spectrometry. Apart from mycotoxins, the content of ergosterol as a marker indicating fungal occurrence was also determined. Among aflatoxins, aflatoxin B1 was the dominant mycotoxin in coffee bean samples, with the highest level at 17.45 ng g-1 . Ochratoxin A was detected in four samples at levels ranging from 1.27 to 4.34 ng g-1 , and fungi potentially producing this toxin, namely Aspergillus oryzae, Alternaria sp., Aspergillus foetidus, Aspergillus tamarii and Penicillium citrinum, were isolated. CONCLUSION: Steaming and decaffeination of coffee beans increased antioxidant activities of brews in comparison with those prepared from unprocessed beans. Although toxins can be quantified in green coffee beans and novel fungi were isolated, their concentrations are acceptable according to legal limits. © 2017 Society of Chemical Industry.

Environmental biodegradation of halophenols by activated sludge from two different sewage treatment plants.

Halophenols make a group of aromatic compounds that are resistible to biodegradation by environmental microorganisms. In this study, the biodegradation of 4-bromo-, 4-chloro- and 4-fluorophenols was studied with two types of activated sludges (from a small rural plant and from a bigger municipal plant) as an inoculum. Because of their wide use, surfactants are present in the wastewater and inhibitors enhance the biodegradation of different pollutants; the influence of natural surfactants on halophenols' biodegradation was also tested. Both types of activated sludge contained bacterial strains which were active in the halophenols' biodegradation process. The coexistence of surfactants and halophenols in the wastewater does not prevent microorganisms from effective halophenols' biodegradation. Moreover, surfactants can enhance the effectiveness of halophenols' removal from the environment. Different cell surface modifications of two isolated bacterial strains were observed in the same system of halophenols with or without surfactants. Halophenols and surfactants may also induce changes in bacteria cell surface properties.

Influence of saponins on the biodegradation of halogenated phenols.

Biotransformation of aromatic compounds is a challenge due to their low aqueous solubility and sorptive losses. The main obstacle in this process is binding of organic pollutants to the microbial cell surface. To overcome these, we applied saponins from plant extract to the microbial culture, to increase pollutants solubility and enhance diffusive massive transfer. This study investigated the efficiency of Quillaja saponaria and Sapindus mukorossi saponins-rich extracts on biodegradation of halogenated phenols by Raoultella planticola WS2 and Pseudomonas sp. OS2, as an effect of cell surface modification of tested strains. Both strains display changes in inner membrane permeability and cell surface hydrophobicity in the presence of saponins during the process of halogenated phenols biotransformation. This allows them to more efficient pollutants removal from the environment. However, only in case of the Pseudomonas sp. OS2 the addition of surfactants to the culture improved effectiveness of bromo-, chloro- and fluorophenols biodegradation. Also introduction of surfactant allowed higher biodegradability of halogenated phenols and can shorten the process. Therefore this suggests that usage of plant saponins can indicate more successful halogenated phenols biodegradation for selected strains.

Biodegradation of Nonylphenol Monopropoxyethoxylates.

Aerobic biodegradation behavior of nonylphenol monopropoxyethoxylates was investigated in two tests with different inocula-sewage sludge and river water. Both primary biodegradation and formation of different biodegradation intermediates were studied. Primary biodegradation of nonylphenol monopropoxyethoxylates was relatively fast and complete with the sewage sludge as the inoculum. On the other hand, biodegradation with river water as the inoculum was slower and primary biodegradation in this test reached only about 60 % during almost 50 days. The biodegradation intermediates from both oxidative and non-oxidative pathways were found. In the non-oxidative route monopropoxy poly(ethylene glycol)s were observed which indicate existence of the central fission biodegradation pathway. In the oxidative pathway carboxylic acids were identified. The biodegradation intermediates identified with the use of high performance liquid chromatography with mass spectrometric detection persisted for many days in both tests.

Development of a Dispersive Liquid-Liquid Microextraction Procedure for Biodegradation Studies on Nonylphenol Propoxylates Under Aerobic Conditions.

Aerobic biodegradation behavior of nonylphenol propoxylates was investigated using dispersive liquid-liquid microextraction as a simple and fast technique for sample preparation. The developed method proved to be efficient for the isolation and concentration of nonylphenol propoxylates before their quantification with the use of high performance liquid chromatography. The primary biodegradation of nonylphenol propoxylates was approximately 80 % by 10 days after the beginning of the test. However, the biodegradation products which were identified with the use of mass spectrometric detection persisted for many days.

Continuous Flow Methylene Blue Active Substances Method for the Determination of Anionic Surfactants in River Water and Biodegradation Test Samples.

Anionic surfactants are commonly determined with the use of the methylene blue active substances (MBAS) standard method, which is time-consuming and labor-intensive. Therefore, new methods for determination of anionic surfactants are needed. In this study, the standard MBAS method for determination of anionic surfactants was modified and adjusted to work in a continuous flow system combined with spectrophotometric measurement. The developed method was found to be satisfactory in terms of sensitivity and precision, with a short time of analysis. The quantification limit for anionic surfactants was at 16 µg L-1, with a relative standard deviation of 1.3 % for a model sample and 3.8 % for a river water sample. The results obtained for environmental samples were comparable to those obtained by using the standard MBAS method; however, the developed continuous flow method is faster, more sensitive and consumes smaller doses of chemical reagents.

Comparison of Biodegradation of Nonylphenol Propoxylates with Usage of Two Different Sources of Activated Sludge.

Aerobic biodegradation behaviour of nonylphenol propoxylates was investigated in two tests with different sewage sludge as inocula. The samples containing target compounds were pre-concentrated using dispersive liquid-liquid microextraction and analysed with the use of high performance liquid chromatography with tandem mass spectrometry. Both primary biodegradation and formation of different biodegradation by-products were studied. Primary biodegradation of nonylphenol propoxylates was relatively slow and reached only about 70 % in over 70 days from the start of the tests. The biodegradation by-products from both oxidative and non-oxidative pathways were found. In the non-oxidative route, shortening of the propoxy chain was observed. In the oxidative pathway carboxylic acids and ketones were identified. The biodegradation by-products identified with the use of mass spectrometric detection also persisted for many days.

Cations impact the biodegradation of iodosulfuron-methyl herbicidal ionic liquids by fungi.

In the framework of this study, six fungal isolates which demonstrated a high capability for biodegrading iodosulphuron-methyl sodium as well as herbicidal ionic liquids based on this herbicide were isolated from different soil samples. The isolates were identified based on the ITS region, whereas biodegradation residues were determined based on LC-MS/MS. Depending on the isolate, the half-lives values of the biodegraded herbicide or herbicidal ionic liquid ranged significantly from just 1.25 days to more than 40 days. The research findings unveiled that the structure of cations is a central limiting factor affecting fungal growth and herbicide transformation in case of ionic liquids. The length of the alkyl chain has been identified as the primary driver of herbicide toxicity, emphasizing the importance of structural factors in herbicide design. In cases when dodecyl(2-hydroxyethyl)dimethyl cation was used, its biodegradation ranged from 0 to approx. 20% and the biodegradability of the iodosulfuron-methyl was notably limited for the majority of the studied isolates. This knowledge provides guidance for development and selection of herbicides with reduced environmental impact. This study highlights the ecological importance of soil fungi, their potential role in herbicide biodegradation, the influence of cations on fungal growth and herbicide transformation, and the structural factors governing herbicide toxicity. Further research in these areas may lead to more efficient and environmentally friendly approaches to herbicide management.

Application of dispersive liquid-liquid microextraction followed by HPLC-MS/MS for the trace determination of clotrimazole in environmental water samples.

A method for the analysis of clotrimazole was developed with dispersive liquid-liquid microextraction for sample pre-concentration and HPLC-MS/MS for analysis. A linear ion trap was used for the confirmation of clotrimazole identity in the samples. The developed method enables the analysis of clotrimazole in river water and sewage effluent from wastewater treatment plants with a LOQ of 0.7 ng/L. Environmental monitoring of clotrimazole was undertaken. Samples from river water and sewage effluents were analysed over a one-year period. Clotrimazole was found in every tested sample with concentration range from 1 to 31 ng/L. The amount of clotrimazole in tested samples was highly dependent on sampling season. The highest results were obtained in summer and autumn.

Biodegradation of Triton X-100 and its primary metabolites by a bacterial community isolated from activated sludge.

A set of studies was carried using a continuous flow biodegradation unit in order to isolate a microbial community capable of efficient and complete utilization of octylphenol ethoxylates from activated sludge. Increasing concentrations of Triton X-100 (in the range of 1-1000 mg/l) were applied over a time period of 35 days in order to select microorganisms, which exhibit high tolerance towards this surfactant. The fate of the surfactant and its primary degradation products was assessed by HPLC/MS. It was observed that even small doses of the surfactant contributed to the disruption of the activated sludge, due to adsorption of primary Triton X-100 metabolites (octylphenol and short-chained ethoxylates) on the cells, although the long-chain octylphenol ethoxylates were efficiently degraded during the isolation process. The toxicity assessment of octylphenol as well as octylphenol di- and monoethoxylates towards activated sludge allowed for determination of EC50 values (8 and 55 mg/l, respectively). The identification of the residual microorganisms revealed the presence of Acinetobacter junii, Acinetobacter calcoaceticus, Aeromonas hydrophilia, Alcaligenes spp., Pseudomonas fluorescens and Sphingomonas capsulata. The isolated community exhibited a high resistance towards Triton X-100 and was capable of growth even at 10,000 mg/l, with the highest specific growth rate (0.47 h(-1)) observed at 4000 mg/l. Under aerobic conditions both octylphenol and the short-chained ethoxylates were completely degraded while no toxic effect towards the isolated bacterial community was observed.

Multi-faceted analysis of bacterial transformation of nitrofurantoin.

Excessive presence of antibiotics and their residues can be dangerous to the natural environment. To reduce this negative effect, efficient strategies to remove them from the ecosystem are required. This study aimed to explore the potential of bacterial strains to degrade nitrofurantoin (NFT). Single strains isolated from contaminated areas, namely Stenotrophomonas acidaminiphila N0B, Pseudomonas indoloxydans WB, and Serratia marcescens ODW152 were employed in this study. Degradation efficiency and dynamic changes within the cells during NFT biodegradation were investigated. For this purpose, atomic force microscopy, flow cytometry, zeta potential, and particle size distribution measurements were applied. Serratia marcescens ODW152 showed the highest performance in removal of NFT (96 % in 28 days). The AFM images revealed modifications of cell shape and surface structure induced by NFT. Zeta potential showed significant variations during biodegradation. Cultures exposed to NFT had a broader size distribution than the control cultures due to increased cells agglomeration or aggregation. 1-Aminohydantoin and semicarbazide were detected as nitrofurantoin biotransformation products. They showed increased cytotoxicity toward bacteria as determined by spectroscopy and flow cytometry. Results of this study suggest that nitrofurantoin biodegradation leads to formation of stable transformation products that significantly affect the physiology and structure of bacterial cells.

Sorption of ionic liquids in soil enriched with polystyrene microplastic reveals independent behavior of cations and anions.

Recently, much attention has been focused on the application of the Ionic Liquids (ILs) with herbicidal activity in agriculture. It has been suggested that through the appropriate selection of cations and anions, one can adjust the properties of ILs, particularly the hydrophobicity, solubility, bioavailability, toxicity. In practical agricultural conditions, it will be beneficial to reduce the mobility of herbicidal anions, such as the commonly applied 2,4-dichlorophenoxyacetic acid [2,4-D] in the soil. Furthermore, microplastics are becoming increasingly prevalent in the soil, potentially stimulating herbicidal sorption. Therefore, we investigated whether cations in ILs influence the mobility of anions in OECD soil supplemented with polystyrene microplastic (PS). For this purpose, we used the 2,4-D based ILs consisting of: a hydrophilic choline cation [Chol][2,4-D] and a hydrophobic choline cation with a C12chain [C12Chol][2,4-D]. Characterization of selected micropolystyrene was carried out using the BET sorption-desorption isotherm, particle size distribution and changes in soil sorption parameters such as soil sorption capacity and cation exchange capacity. Based on the batch sorption experiment, the effect of microplastic on the sorption of individual cations and anions in soil contaminated with micropolystyrene was evaluated. The results obtained indicate that the introduction of a 1-10% (w/w) PS resulted in an 18-23% increase of the soil sorption capacity. However, the sorption of both ILs' cations increased only by 3-5%. No sorption of the [2,4-D] anion was noted. This suggests that cations and anions forming ILs, behave independently of each other in the environment. The results indicate the fact that ILs upon introduction into the environment are not a new type of emerging contaminant, but rather a typical mixture of ions. It is worth noting that when analyzing the behavior of ILs in the environment, it is necessary to follow the fate of both cations and anions.

2,4-D versus 2,4-D based ionic liquids: Effect of cation on herbicide biodegradation, tfdA genes abundance and microbiome changes during soil bioaugmentation.

The commercial formulations of herbicides rely on surfactants which increase the efficiency of active substance. Herbicidal ionic liquids (ILs), in which cationic surfactants are combined with herbicidal anions, allow for additives' reduction and ensure very good herbicide performance with lower doses. We aimed to test the impact of synthetic and natural cations on biological degradation of 2,4-dichlorophenoxyacetic acid (2,4-D). Although primary biodegradation was high, the mineralization in agricultural soil indicated incomplete conversion of ILs to CO2. Even the introduction of naturally-derived cations resulted in an increase in the herbicide's half-lives - from 32 days for [Na][2,4-D] to 120 days for [Chol][2,4-D] and 300 days for the synthetic tetramethylammonium derivative [TMA][2,4-D]. Bioaugmentation with 2,4-D-degrading strains improves the herbicides' degradation, which was reflected by higher abundance of tfdA genes. Microbial community analysis confirmed that hydrophobic cationic surfactants, even those based on natural compounds, played a negative role on microbial biodiversity. Our study provides a valuable indication for further research related to the production of a new generation of environmentally friendly compounds. Moreover, the results shed a new light on the ionic liquids as independent mixtures of ions in the environment, as opposed to treating them as new type of environmental pollutants.