Search Results (17)

The current environmental pollution and energy crises are global concerns that must be addressed. Considering this background, three perovskites (YMnO₃, Co-doped YMnO₃, and Sn-doped YMnO₃) were synthesized via a sol–gel method and characterized by XRD, SEM, and EDX. Their water-splitting electrocatalytic activity was evaluated in a strongly alkaline medium. The highest activity was observed during hydrogen evolution reaction (HER) experiments on a glassy carbon electrode coated with a catalyst ink containing the Co-doped material. Initially, the HER overpotential value at −10 mA/cm² was 0.59 V, and the Tafel slope was 115 mV/dec. Following a chronoamperometric stability test, the overpotential became 0.46 V and the Tafel slope 119 mV/dec. The higher HER activity of the modified electrode is ascribed to a higher number of catalytic sites exposed to the electrolyte solution and the presence of Carbon Black. The photocatalytic activity of the perovskites was investigated as well, using different experimental conditions and simulated solar irradiation. The results show that the photocatalytic activity can be improved by doping, and the highest removal efficiency is achieved in the presence of the Co-doped YMnO₃ when ~60% of 17α-ethynylestradiol is degraded. Furthermore, the initial pH has no favorable effect on the degradation efficiency. The reusability of Co-doped YMnO₃ was also tested and minimal activity loss was found after three photocatalytic cycles. Full article

Typical investigations into the biological consequences of suspected xenobiotics or nutrients introduced in watersheds include analytical chemistry screens of environmental samples—such as periphyton responses or studies of fish condition—which are all costly in terms of equipment, reagents, time, and human resources. An alternative is to assess pollutant effects on waterborne bacteria. A flow cytometric method was developed to yield rapid, same-day results that could be used to proactively screen for suspected chemical inputs into watersheds using water sampling methods that are identical to those in standard use. The analytical methods are microbe cultivation-independent, for use with waterborne bacteria that are typically viable but not culturable. The procedure is quick and inexpensive, generating measures of bacterial esterase that reflect metabolic activity and are sensitive and statistically robust. After phosphate-EDTA incubation to increase cell wall permeability, staining was performed with 5(6) carboxyfluorescein diacetate (enzyme activity) and propidium iodide (cell viability) with three bacterial species in exponential phase growth having been incubated with organic wastewater compounds (atrazine, pharmaceuticals [17α-ethynylestradiol and trenbolone], and antimicrobials [tylosin and butylparaben]). This method successfully detected metabolic changes in all bacterial species, with atrazine inducing the greatest change. Additional fluorescent stains can target specific microbial structures or functions of interest in a particular watershed. This biotechnology can inform analytical chemistry and study of biota at sites of interest and has the potential to be automated. Full article

Vitellogenins (Vtgs) are key yolk precursor proteins in fish, serving as critical indicators of gonadal maturation in females and reliable biomarkers for detecting xeno-oestrogenic pollution, particularly through their expression in juveniles or males. The vtg gene family comprises multiple subtypes that are species-specific, necessitating precise characterisation and quantification for effective use as biomarkers in studies on estrogenic endocrine-disrupting chemicals (EEDCs). In this study, we successfully cloned and characterised the full-length cDNAs of three vtg subtypes (vtgAa, vtgAb, and vtgC) from Scatophagus argus. Differential expression analysis revealed that vtgAb exhibited the highest responsiveness to 17α-ethynylestradiol (EE2) exposure, with a 3-fold increase in vivo at 10.0 μg/g EE2 and a 30-fold increase in vitro at 10⁻⁷ mol/L EE2. The expression patterns were dose- and time-dependent, with peak expression observed 72 h post-exposure. While in vivo assays indicated moderate upregulation, in vitro experiments demonstrated significantly higher expression, attributed to direct hepatocyte interaction with EE2. These findings confirm vtgAb as the most responsive subtype to oestrogen exposure in S. argus and highlight the species’ tolerance to EE2, as compared to more sensitive species like Danio rerio. This study shows the evolutionary conservation of vtg transcripts across teleost species and reinforces the importance of subtype-specific characterisation to advance their application as biomarkers for EEDCs, with significant implications for environmental monitoring and pollution regulation. Full article

Fish are exposed to increased water temperatures and aquatic pollutants, including endocrine-disrupting compounds (EDCs). Although each stressor can disturb fish liver metabolism independently, combined effects may exist. To unveil the molecular mechanisms behind the effects of EDCs and temperature, fish liver cell lines are potential models needing better characterisation. Accordingly, we exposed the rainbow trout RTL-W1 cells (72 h), at 18 °C and 21 °C, to ethynylestradiol (EE2), levonorgestrel (LNG), and a mixture of both hormones (MIX) at 10 µM. The gene expression of a selection of targets related to detoxification (CYP1A, CYP3A27, GST, UGT, CAT, and MRP2), estrogen exposure (ERα, VtgA), lipid metabolism (FAS, FABP1, FATP1), and temperature stress (HSP70b) was analysed by RT-qPCR. GST expression was higher after LNG exposure at 21 °C than at 18 °C. LNG further enhanced the expression of CAT, while both LNG and MIX increased the expressions of CYP3A27 and MRP2. In contrast, FAS expression only increased in MIX, compared to the control. ERα, VtgA, UGT, CYP1A, HSP70b, FABP1, and FATP1 expressions were not influenced by the temperature or the tested EDCs. The RTL-W1 model was unresponsive to EE2 alone, sensitive to LNG (in detoxification pathway genes), and mainly insensitive to the temperature range but had the potential to unveil specific interactions. Full article

Insulin-like growth factors (IGFs) play central roles in the growth and development of vertebrates. Blotched snakehead (Channa maculata), an economically significant fish, exhibits obvious sexual dimorphism and achieves sexual maturity in one year. However, the role of IGFs in C. maculata remains unknown. Three IGF genes were identified in C. maculata, designated as CmIGF1-1, CmIGF1-2, and CmIGF2. The cDNA sequences of these genes are 1184, 655, and 695 bp, encoding putative proteins of 168, 131, and 215 amino acids, respectively, and all three proteins contain a conserved IGF domain. Quantitative real-time PCR (qPCR) revealed the predominant expression of CmIGFs in the liver of adult fish, with higher expression levels observed in males. Notably, CmIGF1-1, CmIGF1-2, and CmIGF2 displayed analogous expression profiles in the liver across various developmental stages, peaking at 365 days after hatching (dah). Subsequently, 600 individuals at 75 dah, at an early developmental stage, were randomly divided equally into six groups and reared in aerated 2 m × 2 m × 2 m cement ponds at 26.0 ± 1.0 °C. Following a one-week acclimatization period, fish without observed abnormalities were intraperitoneally injected with either 17α-ethynylestradiol (EE₂) or 17α-methyltestosterone (MT) at a dose of 10 μg/g body weight. Three groups underwent short-term hormone treatment, and the remaining three groups underwent long-term hormone treatment, which included five injections at two-week intervals over ten weeks. The analysis of CmIGFs expression levels in the liver under different hormone treatments revealed that EE₂ suppressed the expression of CmIGF1-1 and CmIGF1-2 while promoting CmIGF2 expression. In females, MT up-regulated the expression of CmIGF1-1 and CmIGF2 in a time-dependent manner, but consistently inhibited CmIGF2 expression. In males, MT promoted the expression of CmIGFs in a time-dependent manner, reaching peak levels for CmIGF1-1, CmIGF1-2, and CmIGF2 after 8, 10, and 2 weeks of injection, respectively. Additionally, CmIGF1 and CmIGF2 might exhibit a complementary relationship, with a compensatory increase in CmIGF2 expression in response to low CmIGF1 concentration. These findings highlight the potential key role of IGFs upon growth and their regulation by sex steroid hormones in C. maculata, providing a crucial foundation for future research aimed at elucidating the molecular mechanisms underlying the growth dimorphism between female and male blotched snakeheads. Full article

This study analyzed concentrations of 17β-estradiol (E2), estrone (E1), estriol (E3), 17α-ethynylestradiol (EE2), diethylstilbestrol (DES), 17β-estradiol-3-sulfate (E2-3S), estrone-3-sulfate (E1-3S), 17β-estradiol-3-glucuronide (E2-3G), and estrone-3-glucuronide (E1-3G) in river water, received from intensive feedlot operations wastewater in WuLo Creek, Taiwan. Moreover, the estrogen degradation in situ was analyzed. The average concentrations were 54.15 ± 31.42, 9.71 ± 6.42 and 3.55 ± 2.41 ng/L for E1, E2 and E3, respectively. The concentrations and order were similar to the polluted river and higher than most rivers’ concentrations. The conjugated estrogen concentrations ranged from ND to 13.2 ng/L (E1-3S), ND to 10.4 ng/L (E2-3S), ND to 10.0 ng/L (E1-3G), and ND to 3.6 ng/L (E2-3G), and the detection rates were 76%, 71%, 56%, and 15%, respectively. In the present study, the high detection rates of conjugate estrogen were more elevated than the water receiving STP effluent, suggesting that the source was the river water close to the animal wastewater discharge. In the degradation test, the DES concentrations slightly declined after 24 h, but E1-3G did not significantly change over time (p > 0.05). The degradation of free estrogen occurred during the first 12 h period, and residual concentration was not further decreased after 24 h. In the environment, E1 had higher concentrations than E2 and E3, suggesting that E1 was more resistant to degradation than E2 and E3 at low concentrations. However, the degradation test in the present study suggested that E1 rapidly degraded at high ambient concentrations due to the high degradation constant. Full article

The development of efficient strategies for wastewater treatment to remove micropollutants is of the highest importance. Hence, in this study, we presented a rapid approach to the production of biocatalytic membranes based on commercially available cellulose membrane and oxidoreductase enzymes including laccase, tyrosinase, and horseradish peroxidase. Effective enzyme deposition was confirmed based on Fourier transform infrared spectra, whereas results of spectrophotometric measurements showed that immobilization yield for all proposed systems exceeded 80% followed by over 80% activity recovery, with the highest values (over 90%) noticed for the membrane-laccase system. Further, storage stability and reusability of the immobilized enzyme were improved, reaching over 75% after, respectively, 20 days of storage, and 10 repeated biocatalytic cycles. The key stage of the study concerned the use of produced membranes for the removal of hematoporphyrin, (2,4-dichlorophenoxy)acetic acid (2,4-D), 17α-ethynylestradiol, tetracycline, tert-amyl alcohol (anesthetic drug), and ketoprofen methyl ester from real wastewater sampling at various places in the wastewater treatment plant. Although produced membranes showed mixed removal rates, all of the analyzed compounds were at least partially removed from the wastewater. Obtained data clearly showed, however, that composition of the wastewater matrix, type of pollutants as well as type of enzyme strongly affect the efficiency of enzymatic treatment of wastewater. Full article

Degradation of 17α-ethynylestradiol (EE2) and estrogenicity were examined in a novel oxidative bioreactor (OBR) that combines small bioreactor platform (SBP) capsules and UV-LED (ultraviolet light emission diode) simultaneously, using enriched water and secondary effluent. Preliminary experiments examined three UV-LED wavelengths—267, 279, and 286 nm, with (indirect photolysis) and without (direct photolysis) H₂O₂. The major degradation wavelength for both direct and indirect photolysis was 279 nm, while the major removal gap for direct vs. indirect degradation was at 267 nm. Reduction of EE2 was observed together with reduction of estrogenicity and mineralization, indicating that the EE2 degradation products are not estrogens. Furthermore, slight mineralization occurred with direct photolysis and more significant mineralization with the indirect process. The physical–biological OBR process showed major improvement over other processes studied here, at a very short hydraulic retention time. The OBR can feasibly replace the advanced oxidation process of UV-LED radiation with catalyst in secondary sedimentation tanks with respect to reduction ratio, and with no residual H₂O₂. Further research into this OBR system is warranted, not only for EE2 degradation, but also to determine its capabilities for degrading mixtures of pharmaceuticals and pesticides, both of which have a significant impact on the environment and public health. Full article

Often, different types of contaminants in wastewater are suspected of adversely affecting the treatment efficiency of a wastewater treatment plant (WWTP). Therefore, it is essential to study the effects of newly synthesized substances on the activity of activated sludge microorganisms. The aim of this study was to determine the effect of innovative biosurfactants, i.e., sophorolipids quaternary ammonium salts (SQAS), and three common micropollutants (MPs), i.e., diclofenac (DCP), 17α-ethynylestradiol (EE2), and 4-nonylenol (4-NP), on the biochemical activity of activated sludge microorganisms. The effect of all tested substances was more significant on nitrite-oxidizing bacteria (NOB) than on ammonia-oxidizing bacteria (AOB), and least on the respiratory activity of heterotrophic organisms (HET). SQAS inhibited nitrification even at the lowest concentration tested (5 mg L⁻¹) and the inhibition degree was in the range of 37% to 78%; at the highest concentration of SQAS studied (160 mg L⁻¹), it was about 45–96%. In most cases, the degree of inhibition increased when the SQAS concentration approached 80–160 mg L⁻¹. MPs influenced the activity of nitrifiers to a lower extent than SQAS. The inhibition degree varied from 25% to 75%, depending on the micropollutant tested and its concentration. Full article

17α-estradiol (αE2), an endogenous stereoisomer of the hormone 17β-estradiol (E2), is capable of binding to estrogen receptors (ER). We aimed to mathematically describe, using experimental data, the possible interactions between αE2 and sperm ER during the process of sperm capacitation and to develop a kinetic model. The goal was to compare the suggested kinetic model with previously published results of ER interactions with E2 and 17α-ethynylestradiol (EE2). The HPLC-MS/MS method was developed to monitor the changes of αE2 concentration during capacitation. The calculated relative concentrations B_t were used for kinetic analysis. Rate constants k and molar ratio n were optimized and used for the construction of theoretical B(t) curves. Modifications in αE2–ER interactions were discovered during comparison with models for E2 and EE2. These new interactions displayed autocatalytic formation of an unstable adduct between the hormone and the cytoplasmic receptors. αE2 accumulates between the plasma membrane lipid bilayer with increasing potential, and when the critical level is reached, αE2 penetrates through the inner layer of the plasma membrane into the cytoplasm. It then rapidly reacts with the ER and creates an unstable adduct. The revealed dynamics of αE2–ER action may contribute to understanding tissue rejuvenation and the cancer-related physiology of αE2 signaling. Full article

17α-Ethynylestradiol (EE2), a synthetic estrogen used in contraceptive pills, is resistant to hepatic degradation and is excreted in the urine. It is chemically stable and has a negative impact on the endocrine system. The aim of this work was to mathematically describe the possible interaction of EE2 (200, 20, and 2 μg/L) with sperm estrogen receptors during sperm maturation, which is called capacitation. The concentrations of the unbound EE2 remaining in capacitating medium during 180 min of sperm capacitation were determined at 30 min intervals by high performance liquid chromatography with tandem mass spectrometric detection (HPLC-MS/MS) and the data obtained (relative concentrations B_t) were subjected to kinetic analysis. The suggested kinetic schema was described by the system of differential equations with the optimization of rate constants used to calculate the theoretical B_t values. Optimal parameters (overall rate constants K₁–K₅ and molar ratio n) were determined by searching the minimum of absolute values of the difference between theoretical and experimental B_t values. These values were used for the design of the theoretical B(t) curves which fit to experimental points. The proposed kinetic model assumes the formation of an unstable adduct between EE2 and the receptor in cytoplasm, which acts as an autocatalytic agent and gradually decomposes. Full article

In this study, we present an innovative new bio-treatment approach for 17α-ethynyestradiol (EE2). Our solution for EE2 decontamination was accomplished by using the SBP (Small Bioreactor Platform) macro-encapsulation method for the encapsulation of two bacterial cultures, Rhodococcus zopfii (R. zopfii ) and Pseudomonas putida F1 (P. putida). Our results show that the encapsulated R. zopffi presented better biodegradation capabilities than P. putida F1. After 24 h of incubation on minimal medium supplemented with EE2 as a sole carbon source, EE2 biodegradation efficacy was 73.8% and 86.5% in the presence of encapsulated P. putida and R. zopfii, respectively. In the presence of additional carbon sources, EE2 biodegradation efficacy was 75% and 56.1% by R. zopfii and P. putida, respectively, indicating that the presence of other viable carbon sources might slightly reduce the EE2 biodegradation efficiency. Nevertheless, in domestic secondary effluents, EE2 biodegradation efficacy was similar to the minimal medium, indicating good adaptation of the encapsulated cultures to sanitary effluents and lack of a significant effect of the presence of other viable carbon sources on the EE2 biodegradation by the two encapsulated cultures. Our findings demonstrate that SBP-encapsulated R. zopfii and P. putida might present a practical treatment for steroidal hormones removal in wastewater treatment processes. Full article

A successful attempt to degrade synthetic estrogen 17α-ethynylestradiol (EE2) is demonstrated via combining photocatalysis employing magnesium peroxide (MgO₂)/low-pressure ultraviolet (LP-UV) treatment followed by biological treatment using small bioreactor platform (SBP) capsules. Reusable MgO₂ was synthesized through wet chemical synthesis and extensively characterized by X-ray diffraction (XRD) for phase confirmation, X-ray photoelectron spectroscopy (XPS) for elemental composition, Brunauer-Emmett-Teller (BET) to explain a specific surface area, scanning electron microscopy (SEM) imaging surface morphology, and UV-visible (Vis) spectrophotometry. The degradation mechanism of EE2 by MgO₂/LP-UV consisted of LP-UV photolysis of H₂O₂ in situ (produced by the catalyst under ambient conditions) to generate hydroxyl radicals, and the degradation extent depended on both MgO₂ and UV dose. Moreover, the catalyst was successfully reusable for the removal of EE2. Photocatalytic treatment by MgO₂ alone required 60 min (~1700 mJ/cm²) to remove 99% of the EE2, whereas biodegradation by SBP capsules alone required 24 h to remove 86% of the EE2, and complete removal was not reached. The sequential treatment of photocatalysis and SBP biodegradation to achieve complete removal required only 25 min of UV (~700 mJ/cm²) and 4 h of biodegradation (instead of >24 h). The combination of UV photocatalysis and biodegradation produced a greater level of EE2 degradation at a lower LP-UV dose and at less biodegradation time than either treatment used separately, proving that synergetic photocatalysis and biodegradation are effective treatments for degrading EE2. Full article

In this study, two hormones 17β-estradiol (E₂) and 17α-ethynylestradiol (EE₂), and three phenolic compounds, bisphenol A (BPA), 4-N-nonylphenol (4-NP) and 4-tert-octylphenol (4-t-OP), were determined in surface water in the Cuautla River at the State of Morelos during the dry-season in Mexico. The endocrine disrupting compounds (EDCs) were extracted from water samples using solid-phase extraction (SPE) with end-capped C₁₈, and then the extracts were chemically derivatized to TMS (trimethylsylane)-compounds and analyzed by gas chromatography coupled to mass spectrometry (GCMS). The most abundant compound was BPA (22.46 ± 30.17 ng L⁻¹), followed by 4-t-OP (11.24 ± 11.76 ng L⁻¹), 4-NP (7.53 ± 14.88 ng L⁻¹), EE₂ (2.37 ± 4.36 ng L⁻¹) and E₂ (0.97 ± 1.82 ng L⁻¹). The residual amounts of target compounds could either reach stream surface water from direct domestic wastewater discharges, conventional wastewater treatment plant or can be a result from the use of agrochemicals in crop areas. The EDCs in Cuautla River exerted a high pressure on the aquatic ecosystem because their presences in surface water caused medium and high potential ecological risk. Besides, it was found that aquatic organisms were exposed to estrogenic activity. Full article

As a special zone of periodic impoundment and flooding in the Three Gorges Reservoir (TGR), the water-level fluctuation zone (WLFZ) of TGR acts as a short-term ‘sink’ for hydrophobic endocrine disrupting compounds (EDCs). This study was conducted on the adsorption/desorption kinetics and equilibriums of four target EDCs (i.e., estrone (E1), 17β-estradiol (E2), 17α-ethynylestradiol (EE2), and bisphenol A (BPA)) in soil samples (i.e., S1, S2, S3, and S4), which were collected from different elevation gradients of the WLFZ at Qingxi Town of Fulin in TGR. Under the influence of the water-level fluctuation, S1 and S2 from the frequent inundation area had smaller particle sizes with more organic matter (OM) and total nitrogen (TN) content, whereas soils S3 and S4 from the long-term exposed area had a higher fraction of sand with lower OM and TN. All four target EDCs could achieve an adsorption equilibrium within 24 h, and the kinetics of the adsorption/desorption fitted the pseudo-second-order model excellently. The adsorption/desorption isotherms of the EDCs were better described by the Freundlich equation. The adsorption capacity decreased, as 17α-ethynylestradiol (EE2) > 17β-estradiol (E2) > estrone (E1) > bisphenol A (BPA), in each tested soil. S1 and S2 exhibited a greater capacity but a lower degree of nonlinearity to adsorb the target EDCs than S3 and S4. The values of the Gibbs free energy suggested that the EDCs adsorption in the tested soils was dominated by unstable physical adsorption. The desorption hysteresis of E1, E2, and EE2 were stronger in S1 and S2, whereas the BPA exhibited weak or almost no hysteresis in all of the tested soils. The substantial water-level fluctuation imposed on the TGR would have a continuous influence on the EDCs adsorption/desorption by altering the soil properties. Thus, long-term monitoring and further research of EDCs in this region are urgent. Full article