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Understanding the differential impacts of two antidepressants on locomotion of freshwater snails (Lymnaea stagnalis) Texte intégral
2024
Raman, Nandini Vasantha | Dubey, Asmita | van Donk, Ellen | von Elert, Eric | Lürling, Miquel | Fernandes, Tânia V. | de Senerpont Domis, Lisette N.
There is growing evidence of negative impacts of antidepressants on behavior of aquatic non-target organisms. Accurate environmental risk assessment requires an understanding of whether antidepressants with similar modes of action have consistent negative impacts. Here, we tested the effect of acute exposure to two antidepressants, fluoxetine and venlafaxine (0–50 µg/L), on the behavior of non-target organism, i.e., freshwater pond snail, Lymnaea stagnalis. As compounds interact with chemical cues in the aquatic ecosystems, we also tested whether the effects altered in the presence of bile extract containing 5α-cyprinol sulfate (5α-CPS), a characterized kairomone of a natural predator, common carp (Cyprinus carpio). Behavior was studied using automated tracking and analysis of various locomotion parameters of L. stagnalis. Our results suggest that there are differences in the effects on locomotion upon exposure to venlafaxine and fluoxetine. We found strong evidence for a non-monotonic dose response on venlafaxine exposure, whereas fluoxetine only showed weak evidence of altered locomotion for a specific concentration. Combined exposure to compounds and 5α-CPS reduced the intensity of effects observed in the absence of 5α-CPS, possibly due to reduced bioavailability of the compounds. The results highlight the need for acknowledging different mechanisms of action among antidepressants while investigating their environmental risks. In addition, our results underline the importance of reporting non-significant effects and acknowledging individual variation in behavior for environmental risk assessment.
Afficher plus [+] Moins [-]Exploring long-term retention and reactivation of micropollutant biodegradation capacity Texte intégral
2024
Branco, Rita H.R. | Meulepas, Roel J.W. | Rijnaarts, Huub H.M. | Sutton, Nora B.
The factors limiting micropollutant biodegradation in the environment and how to stimulate this process have often been investigated. However, little information is available on the capacity of microbial communities to retain micropollutant biodegradation capacity in the absence of micropollutants or to reactivate micropollutant biodegradation in systems with fluctuating micropollutant concentrations. This study investigated how a period of 2 months without the addition of micropollutants and other organic carbon affected micropollutant biodegradation by a micropollutant-degrading microbial community. Stimulation of micropollutant biodegradation was performed by adding different types of dissolved organic carbon (DOC)—extracted from natural sources and acetate—increasing 10 × the micropollutant concentration, and inoculating with activated sludge. The results show that the capacity to biodegrade 3 micropollutants was permanently lost. However, the biodegradation activity of 2,4-D, antipyrine, chloridazon, and its metabolites restarted when these micropollutants were re-added to the community. Threshold concentrations similar to those obtained before the period of no substrate addition were achieved, but biodegradation rates were lower for some compounds. Through the addition of high acetate concentrations (108 mg-C/L), gabapentin biodegradation activity was regained, but 2,4-D biodegradation capacity was lost. An increase of bentazon concentration from 50 to 500 µg/L was necessary for biodegradation to be reactivated. These results provide initial insights into the longevity of micropollutant biodegradation capacity in the absence of the substance and strategies for reactivating micropollutant biodegrading communities. Graphical abstract: (Figure presented.)
Afficher plus [+] Moins [-]Iron-loaded activated carbon cloth as CDI electrode material for selective recovery of phosphate Texte intégral
2024
Sharker, Tanzila | Gamaethiralalage, Jayaruwan G. | Qu, Qiyang | Xiao, Xinxin | Dykstra, Jouke E. | de Smet, Louis C.P.M. | Muff, Jens
This study investigated the efficacy of oxidised iron-loaded activated carbon cloth (Fe-ACC) for selective recovery of phosphorous. The capacitive deionisation (CDI) technology was employed, for rapid removal of phosphate, with the aim of reducing the reliance on high alkalinity environment for the regeneration of Fe-ACC electrode. Multiple experimental parameters, including applied potential, pH, and co-existing ions, were studied. Additionally, the CDI system was tested on a real water matrix (Lake Ormstrup, Denmark) to elucidate the electrodes’ performance on selective recovery of phosphate. About 69 ± 10% of the adsorbed phosphate were released at pH 12 via pure chemical desorption, which was ~ 50% higher than that at pH 9. The CDI system successfully demonstrated the selective removal of phosphate from the lake water. It reduced the concentration of phosphate from 1.69 to 0.49 mg/L with a 71% removal efficiency, while the removal percentages of other anions, namely chloride, sulphate, bromide, nitrite, nitrate, and fluoride, were 10%, 7%, 1%, 1.5%, 4%, and 7%, respectively.
Afficher plus [+] Moins [-]Isolation of Freshwater Algae from Some Reservoirs of Chiang Mai Rajabhat University, Mae Rim Campus, Chiang Mai Texte intégral
2024
Pongpan Leelahakriengkrai, Phitsanuphakhin Chaimongkhon and Tatporn Kunpradid
A study on the biodiversity and isolation of freshwater algae from some reservoirs of Mae Rim Campus, Chiang Mai Rajabhat University, Chiang Mai Province, collected algal samples and assessed the water quality at four reservoirs, including Wiang Bua Reservoir, Ma Lang Por Reservoir, Education Auditorium reservoir, and Kru Noi Garden Reservoir. One hundred and six species of algae belonging to 8 phyla were found. The most prominent species were Cylindrospermopsis philippinensis, Trachelomonas volvocina, Peridiniopsis sp., and Coelastrum astroideum, respectively. The overall water quality was categorized as clean according to some physical and chemical parameters by the National Environmental Board of Thailand. However, high BOD values were detected at some sampling points. The algae isolation included 8 isolates, which could be utilized for various purposes in the future, such as biomass, protein, polysaccharide energy, bioactive compounds, antioxidant substances, wastewater treatment, environmental indicators, algal toxins, and phylogenetic studies. All strains were stored at the Centre of Excellence of Biodiversity Research and Implementation for Community, Chiang Mai Rajabhat University, for conservation and future development purposes.
Afficher plus [+] Moins [-]Identification and Functional Annotation of Echium plantagineum Metallothioneins for Reduction in Heavy Metals in Soil Using Molecular Docking Texte intégral
2024
Y. S. Rasheed, M. S. AL-Janaby and M. H. Abbas
Heavy metal contamination in soil poses a significant environmental challenge globally, affecting agricultural productivity and human health. Phytoremediation, using plants to extract and detoxify heavy metals, presents a promising solution. This study investigates the novel potential of Echium plantagineum, a metal-tolerant species, in phytostabilization and phytoremediation and explores the role of metallothioneins in heavy metal reduction. A comprehensive literature review identified known metallothioneins involved in heavy metal reduction across various plant species. Moreover, genome annotation and gene prediction of Echium plantagineum were performed, predicting a total of 39,520 proteins. This comprehensive protein list facilitates the identification of metallothioneins or other metal-related proteins with potential functional roles in heavy metal tolerance, suggesting new targets to improve the effectiveness of phytoremediation. The sequences of these proteins were utilized to construct a protein BLAST database, against which known metallothioneins protein sequences from other plant species were subjected to BLAST searches, resulting in 41 top hits. Subsequent 3D modeling, structural analysis, protein-metal virtual screening, and functional annotation of the proteins revealed novel high affinities of Ctr copper transporter, zinc/iron permease, and nicotianamine synthase proteins with nickel, zinc, and zinc ion, suggesting their unexplored roles in the uptake of aforementioned ligands. Notably, this study identifies novel metallothioneins proteins in Echium plantagineum, highlighting their role in metal tolerance and phytoremediation.
Afficher plus [+] Moins [-]GIS-Based Assessment of Soil Erosion Using the Revised Universal Soil Loss Equation (RUSLE) Model in Morigaon District, Assam, India Texte intégral
2024
Ananya Saikia, Monjit Borthakur and Bikash Jyoti Gautam
Soil erosion in the agricultural landscape of Assam has been impacting the livelihoods of millions. In administrative regions like districts, which are vulnerable to natural disasters like floods and bank erosion, GIS-based soil erosion estimating studies can help planners and policymakers identify areas of soil erosion to implement scientific conservation measures. The main purpose of this study is to estimate soil loss and to determine soil loss zones in the Morigaon district of Assam. The Revised Universal Soil Loss Equation (RUSLE) combined with GIS has been incorporated into the present study. The five parameters of RUSLE, namely, rainfall-runoff erosivity, soil erodibility, topographic factor, cover management, and conservation practices, are individually estimated from relevant and authentic data sources, and all these parameters are quantified in GIS. The research findings show that 46.89% of areas in the district are in moderate soil loss zone, eroding 0.78 ton/ha/year, 34.27% of areas are in low soil loss zone, 15.36% of areas are in high soil loss zone, eroding about 12.22 ton/ha/year and 3.47% of areas are in a very high soil loss zone, eroding 192.8 ton/ha/year. The high soil loss zones mainly cover the riverine areas and bare lands in the district. As per our estimation, there is an average of 205.85 tonnes of soil loss in the district per hectare per year.
Afficher plus [+] Moins [-]Environmental Impact of Al-Dalmaj Marsh Discharge Canal on the Main Outfall Drain River in the Eastern part of Al-Qadisiya City and Predicting the IQ-WQI with Sensitivity Analysis Using BLR Texte intégral
2024
Zahraa Z. Al-Janabi, Idrees A. A. Al-Bahathy, Jinan S. Al-Hassany, Rana R. Al-Ani, Ahmed Samir Naje and Afrah A. Maktoof
Monitoring water quality changes in any body of water is crucial as it directly relates to climate change. Evaluating the quality and quantity of fresh water for various uses is essential to maintaining safe water sources now and in the future. This study examined the water quality of the Main Outfall Drain River (MOD) in the eastern part of Al-Qadisiya Governorate at three sites over four seasons in 2023, using the Iraqi Water Quality Index (IQ-WQI). In most cases, the concentrations of dissolved oxygen (DO), biochemical oxygen demand (BOD5), and total dissolved solids (TDS) exceeded allowable limits for freshwater and aquatic life protection. The major contributing parameters to the river’s low water quality were TDS, BOD5, turbidity, and DO. The use of the MOD for discharging agricultural effluents led to increased levels of TDS, BOD5, and turbidity. Temporal variation indicated that the summer season had the highest values compared to other seasons due to increased evaporation and low water discharge. Spatial variation showed the IQ-WQI of the sites in descending order from very poor water to unsuitable, with Site 3 having double the TDS concentrations compared to other sites. This increase may be attributed to the impact of the Al-Dalmag Marsh discharge canal, which comes into contact with the MOD at this site. Sensitivity analysis using backward linear regression was applied to predict the IQ-WQI and determine the most influential parameters on the IQ-WQI score. The test was conducted for two sets of water parameters (from the IQ-WQI calculation) and included 7 parameters for each freshwater and aquatic life use, obtaining different models.
Afficher plus [+] Moins [-]Phenopalynological Study of Some Ornamental Species in the Giza Region, Egypt Texte intégral
2024
W. K. Taia, W. M. Amer, A. B. Hamed and A. M. Abd El-Maged
Mature flower buds were collected from twenty species planted on the different roads in the Giza district from May to September 2022 and 2023. The pollen grains were examined carefully and photographed using a 40x10x magnification lens in an OPTICA (B-150D) light microscope fitted with a USB digital video Camera and Computer Software. At least 30 pollen grains/each species were measured and described. Non-catalyzed pollens were sputtered onto Aluminum stubs, coated with 30 nm gold, and examined and photographed using JEOL JSL IT 200 SEM. The morphological characters of the pollen grains were examined. According to the pollen size Acalypha wilkesiana and Tecoma stans were the smallest pollen grains, from 20.0μm to 26.0μm, which facilitate their introduction to the nose causing asthma and rhinitis. Clerodendrum inerme pollen grains have echinate exine surface, which causes allergic symptoms more than the psilate ones. Plumbago capensis has intectate exine with echinate columella causing human disorders. This study demonstrates the critical position of air pollution in this area with the change in the phenological aspects of the plants resulting in producing immature pollen grains in huge amounts, which cause human disorders and pollinosis. Our results showed that the studied species can induce allergy in one way or another if we consider the situation of the studied area, weather pattern, and pollen characteristics.
Afficher plus [+] Moins [-]Mechanism and Behavior of Phosphorus Adsorption from Water by Biochar Forms Derived from Macadamia Husks Texte intégral
2024
Nguyen Van Phuong
High phosphate content in water causes eutrophication, leading to many risks to the aquatic environment and human health. This study used biochar derived from macadamia husks at the pyrolysis temperatures (300, 450, and 600℃) to remove P from water. Adsorption parameters such as initial pH, biochar dosage, initial P concentration, and adsorption time when biochar was exposed to the P solution were determined. The results show that pH 4 is optimal for P removal with biochar pyrolyzed at 300 and 450°C, while pH 6 gives biochar 600°C, biochar dosage 10 g.L−1, concentration Initial P 25-200 mg.L−1 and adsorption time 40 minutes for 3 types of biochar. The maximum P adsorption capacity is 20.07, 20.03, and 20.03 mg.L−1 corresponding to 3 forms of biochar 300, 450, and 600°C. P adsorption data were consistent with the Freundlich isotherm model for all three biochar forms. The pseudo-second-order kinetic model was suitable for all three types of biochar, showing that the main adsorption mechanism is a surface chemical reaction. The study suggested that hydrogen bonding plays an important role in the adsorption of P onto biochar derived from macadamia husks. This study indicates that biochar derived from macadamia husks pyrolyzed at temperatures of 300, 450, and 600°C are all potentially effective and low-cost adsorbents for phosphate removal from water.
Afficher plus [+] Moins [-]Phytochemistry of Aloe vera: A Catalyst for Environment-Friendly Diverse Nanoparticles with Sustained Biomedical Benefits Texte intégral
2024
S. Yadav, A. Khan and J. G. Sharma
Nanotechnology has become one of the most active fields in the research area and is getting more attention toward nanoparticle synthesis. Green synthesis methods using various plants, fungi, bacteria, and algae were used to synthesize nanoparticles with proper requirements and maintain sterile conditions to get the desired products. Aloe vera, a bio-medicinal plant, contains a wide range of phytochemicals such as phenolic, hydroxyl groups, alkaloids, polyols, polysaccharides, etc, which act as reducing and capping agents with high efficiency. This review revealed that aloe vera-derived nanoparticles are safe, stable, cost-effective, and eco-friendly, and they also possess significant applications for drug targeting, disease resistance, tissue engineering, wound healing, anticancer, antibacterial, and cosmetic industries. Synthesized metal nanoparticles are characterized through UV-visible spectroscopy, X-ray diffraction, scanning electron and transmission electron microscopy, photoluminescence, and the Well-diffusion method. It is highly interesting to note that aloe vera-mediated silver and zinc nanoparticles possess high potency against multi-drug resistant pathogens. Here, anticancer, antioxidant, anti-inflammatory, and photocatalytic activity separately showed by aloe vera peel, gel, and leaf, along with possible challenging situations faced during plant extract-based nanoparticle synthesis, are highlighted. Additionally, the introduction of GMOs is subjected to play an important role in advancing green methods. However, more research is required to estimate the dose’s safety, degradation, and synergistic mechanism inside the human body for better use of the green method for the treatment of microbial infections.
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