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Per- and polyfluoroalkyl substances (PFAS) are fluorinated and refractory pollutants that are ubiquitous in industrial wastewater. Photocatalytic destruction of such pollutants with catalysts such as TiO2 and ZnO is an attractive avenue for removal of PFAS, but refined forms of such photocatalysts are expensive. This study, for the first time, utilized milled unrefined raw mineral ilmenite, coupled to UV-C irradiation to achieve mineralization of the two model PFAS compounds perfluorooctanoic acid (PFOA) and perfluoro octane sulfonic acid (PFOS). Results obtained using a bench-scale photocatalytic reactor system demonstrated rapid removal kinetics of PFAS compounds (>90% removal in less than 10 h) in environmentally-relevant concentrations (200-1000 ppb). Raw ilmenite was reused over three consecutive degradation cycles of PFAS, retaining >80% removal efficiency. Analysis of degradation products indicated defluorination and the presence of shorter-chain PFAS intermediates in the initial samples. End samples indicated the disappearance of short-chain PFAS intermediates and further accumulation of fluoride ions, suggesting that original PFAS compounds underwent mineralization due to an oxygen-radical-based photocatalytic destruction mechanism induced by TiO2 present in ilmenite and UV irradiation. The outcome of this study implies that raw ilmenite coupled to UV-C is suitable for cost-effective reactor operation and efficient photocatalytic destruction of PFAS compounds.
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Stormwater pollution is a key factor contributing to water quality degradation, posing substantial environmental and human health risks. Although stormwater retention ponds, also referred to as wet ponds, are commonly implemented to alleviate stormwater challenges by reducing peak flow and removing suspended solids, their effectiveness in removing heavy metals and nutrients is limited. This study evaluated the performance of floating treatment platforms (FTPs) featuring vetiver grass (Chrysopogon zizanioides), a non-invasive, nutrient- and metal-accumulating perennial grass, in removing heavy metals (Cu, Pb, and Zn) and nutrients (P and N) in stormwater retention ponds. Furthermore, the potential for utilizing the spent vetiver biomass for generating biochar and bioethanol was investigated. The study was conducted in a greenhouse setup under simulated wet and dry weather conditions using pond water collected from a retention pond in Stafford Township, New Jersey, USA. Two FTPs with vetiver (vegetated FTPs) were compared with two FTPs without vetiver (non-vegetated FTPs), which served as controls. Results showed that the removal of heavy metals and nutrients by the FTPs with vetiver was significantly higher (p < 0.05) than the FTPs without vetiver. Notably, vetiver showed resilience to stormwater pollutants and hydroponic conditions, displaying no visible stress symptoms. The biochar and bioethanol generated from the spent vetiver exhibited desirable yield and quality, without raising concerns regarding pollutant leaching, indicated by very low TCLP and SPLP concentrations. This study provides compelling evidence that the implementation of vetiver-based FTPs offers a cost-effective and environment-friendly solution for mitigating stormwater pollution in retention ponds. Furthermore, the utilization of vetiver biomass for biofuel and biochar production supports clean production and fostering circular economy efforts.
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Biomassa , Carvão Vegetal , Etanol , Metais Pesados , Poluentes Químicos da Água , Carvão Vegetal/química , Metais Pesados/análise , Etanol/química , Poluentes Químicos da Água/análise , Vetiveria , Poaceae , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , ChuvaRESUMO
Soil microbial communities undergo constant fluctuations, particularly in response to environmental factors. Although the deposition of toxic mine waste is recognized for introducing potentially hazardous elements (PHEs) into the soil, its specific impacts on microbial communities remain unclear. This study aims to explore the combined effects of soil alkalinity and bioavailable PHEs on microbial diversity and traits in agricultural soil adjacent to a chromium-asbestos mining area. By employing a comprehensive analysis, this study indicated that microbiological attributes were reduced in contaminated areas (zone 1), whereas both the levels of bioavailable PHEs (CrWs: 31.08 mg/kg, NiWs: 13.90 mg/kg) and alkalinity indices (CROSS, MCAR, MH) were significantly higher. The spatial distribution of soil alkalinity and bioavailable PHEs, primarily originating from chromium-asbestos mines, has been determined. This study also elucidates the negative relationship between soil stressors (Alkalinity and PHEs) and microbial activities (soil enzymatic activity, microbial respiration, and biomass carbon). The vector's length exhibited a notable difference between zone 1 (0.51) and zone 2 (0.32), indicating a substantial limitation on carbon (C). Also, the investigation of soil bacterial diversity unveiled notable disparities in the prevalence of microbial populations inside zone 1. Proteobacteria constituted 57.18% of the total population indicating a noteworthy prevalence in the contaminated soils. Finally, the random forest (RF) algorithm from machine learning was selected and proven to be a robust choice in Taylor diagrams for predicting the causative stressors responsible for the deterioration of soil microbial health. Therefore, this research offers insights into the health and resilience of soil microbial communities under synergistic stress conditions, which will aid environmentalists in planning future interventions and improving sustainable farming techniques.
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Cromo , Mineração , Microbiologia do Solo , Poluentes do Solo , Solo , Poluentes do Solo/análise , Cromo/análise , Solo/química , Agricultura , Bactérias/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Concentração de Íons de HidrogênioRESUMO
The use of arsenic (As) for various industrial and agricultural applications has led to worldwide environmental contamination. Phytoremediation using hyperaccumulators is a sustainable soil As mitigation strategy. Microbial processes play an important role in the tolerance and uptake of trace elements such as in plants. The rhizospheric and endophytic microbial communities are responsible for accelerating the mobility of trace elements around the roots and the production of plant growth-promoting compounds and enzymes. Several studies have reported that the As hyperaccumulator, Pteris vittata L. (PV) influences the microbial community in its rhizosphere and roots. Deciphering the differences in the microbiomes of hyperaccumulators and non-accumulators is crucial in understanding the mechanism of hyperaccumulation. We hypothesized that there are significant differences in the microbiome of roots, rhizospheric soil, and bulk soil between the hyperaccumulator PV and a non-accumulator of the same genus, Pteris ensiformis Burm. (PE), and that the differential recruitment of bacterial communities provides PV with an advantage in As contaminated soil. We compared root endophytic, rhizospheric, and bulk soil microbial communities between PV and PE species grown in As-contaminated soil in a greenhouse setting. There was a significant difference (p < 0.001) in the microbiome of the three compartments between the ferns. Differential abundance analysis showed 328 Amplicon Sequence Variants (ASVs) enriched in PV compared to 172 in PE. The bulk and rhizospheric soil of both ferns were abundant in As-resistant genera. However, As-tolerant root endophytic genera were present in PV but absent in PE. Our findings show that there is a difference between the bacterial composition of an As hyperaccumulator and a non-accumulator species grown in As-contaminated soil. These differences need to be further explored to develop strategies for improving the efficiency of metal uptake in plants growing in As polluted soil.
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Arsênio , Gleiquênias , Pteris , Oligoelementos , Agricultura , SoloRESUMO
Potentially toxic elements (PTEs) contamination in the agricultural soil can generate a detrimental effect on the ecosystem and poses a threat to human health. The present work evaluates the PTEs concentration, source identification, probabilistic assessment of health hazards, and dietary risk analysis due to PTEs pollution in the region of the chromite-asbestos mine, India. To evaluate the health risks associated with PTEs in soil, soil tailings and rice grains were collected and studied. The results revealed that the PTEs concentration (mainly Cr and Ni) of total, DTPA-bioavailable, and rice grain was significantly above the permissible limit in site 1 (tailings) and site 2 (contaminated) as compared with site 3 (uncontaminated). The Free ion activity model (FIAM) was applied to detect the solubility of PTEs in polluted soil and their probable transfer from soil to rice grain. The hazard quotient values were significantly higher than the safe (FIAM-HQ < 0.5) for Cr (1.50E+00), Ni (1.32E+00), and, Pb (5.55E+00) except for Cd (1.43E-03), Cu (5.82E-02). Severity adjustment margin of exposure (SAMOE) results denote that the PTEs contaminated raw rice grain has high health risk [CrSAMOE: 0.001; NiSAMOE: 0.002; CdSAMOE: 0.007; PbSAMOE: 0.008] for humans except for Cu. The Positive matrix factorization (PMF) along with correlation used to apportion the source. Self-organizing map (SOM) and PMF analysis identified the source of pollution mainly from mines in this region. Monte Carlo simulation (MCS) revealed that TCR (total carcinogenic risk) cannot be insignificant and children were the maximum sufferers relative to adults via ingestion-pathway. In the spatial distribution map, the region nearer to mine is highly prone to ecological risk with respect to PTEs pollution. Based on appropriate and reasonable evaluation methods, this work will help environmental scientists and policymakers' control PTEs pollution in agricultural soils near the vicinity of mines.
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Metais Pesados , Poluentes do Solo , Criança , Adulto , Humanos , Metais Pesados/análise , Cádmio/análise , Monitoramento Ambiental/métodos , Ecossistema , Chumbo/análise , Poluentes do Solo/análise , Solo , Índia , Medição de Risco , ChinaRESUMO
Phosphorus and metals in stormwater runoff are major causes of water quality degradation. Bioretention systems are increasingly implemented to improve stormwater quality and to better manage stormwater quantity. Many studies have focused on modifying the composition of the soil bed to improve pollutant removal. However, the pollutant removal performance of bioretention systems can diminish over time, such as when clogging of the media occurs. Sediment accumulation on the soil surface may inhibit infiltration into the soil bed, thus limiting pollutant removal. Soil replacement may be eventually required as pollutants accumulate in the soil. In this study, a green retrofit material, called green engineered mulch (GEM), was generated by coating regular wood mulch with aluminum-based water treatment residuals (WTR) via a simple and low-energy process (patent pending). The GEM was developed to serve as a green retrofit for bioretention systems to enhance the removal of phosphorus and metals from stormwater runoff. The GEM was placed in a rain garden in Secaucus, NJ, USA for 15 months, during which 12 storm events (ranging from 6.0 mm to 89.6 mm) were monitored. Runoff and infiltrate samples were analyzed for dissolved and total concentrations of phosphorus and metals, along with other key water quality parameters. The GEM significantly reduced (p < 0.05) the total concentrations of phosphorus and metals in stormwater infiltrate compared to the inlet, unlike the regular mulch. Minimal or no contact with the GEM resulted in no significant pollutant removal from surface runoff. No significant pollutant export from the GEM was observed. The spent GEM can be disposed of as non-hazardous waste in municipal landfills. This study demonstrates that the GEM is a safe and effective retrofit. Moreover, the GEM is a simple and economical retrofit solution that can be used in place of regular mulch in bioretention systems.
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Poluentes Ambientais , Fósforo , Metais , Qualidade da Água , Chuva , SoloRESUMO
Exposure to arsenic (As) from a diet of contaminated rice is a widespread problem and a serious concern in several parts of the world. There is a need to develop sustainable, effective, and reliable strategies to reduce As accumulation in rice. Our goal was to develop and test a simple crop rotation method of alternating rice with the As hyperaccumulator plant, Chinese brake fern (Pteris vitatta L.), to reduce As concentrations in rice grains. A greenhouse column study was performed for 2 years using As-contaminated rice paddy soil from West Bengal. Rice was grown under flooded conditions and irrigated with As-contaminated water to simulate field conditions. Chinese brake fern was grown between two rice cycles in experimental columns, while control columns were left unplanted. Our results show that at the end of two cycles, there was a statistically significant decrease in soil As concentrations in the treatment columns compared to the control columns. After one rotation with the fern, there was a significant decline in As concentrations in rice grains in treatment plants and a concomitant decline in both noncarcinogenic and carcinogenic health risks. Our results indicate that there could be substantial benefit in implementing this simple crop rotation model to help lower human health risks from As exposure via rice ingestion.
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Arsênio , Oryza , Pteris , Poluentes do Solo , Humanos , Poluição da Água , Solo , Produção AgrícolaRESUMO
Vetiver root is widely used to produce essential oils in the aromatherapy industry. After the extraction of oil, the roots are disposed of as waste. The central objective of this research was to explore the conversion of this waste into a resource using a circular economy framework. To generate biochar, vetiver roots were pyrolyzed at different temperatures (300, 500, and 700 °C) and residence times (30, 60, and 120 min). Analysis showed the root biochar generated at 500 °C and held for 60 min had the highest surface area of 308.15 m2/g and a yield of 53.76%, in addition to other favorable characteristics. Comparatively, the surface area and the yield of shoot biochar were significantly lower compared to those of the roots. Repurposing the spent root biomass for environmental and agronomic benefits, our circular economy concept prevents the plant tissue from entering landfills or the waste stream.
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Agricultura , Aromaterapia , Carvão Vegetal , Biomassa , IndústriasRESUMO
Phosphorus and heavy metals are washed off and transported with stormwater runoff to nearby surface water bodies resulting in environmental and human health risks. Catch basins remain one of the primary gateways through which stormwater runoff and pollutants from urban areas are transported. Retrofitting catch basins to enhance their phosphorus and heavy metal removal can be an effective approach. In this study, aluminum-based water treatment residual (WTR, a non-hazardous byproduct of the water treatment process) was granulated via a green method to serve as a sustainable filter material, called WTR granules, for enhancing the capabilities of catch basins to remove phosphorus and heavy metals. The WTR granules were field tested in a parking lot in Hoboken, New Jersey. Twelve storm events were monitored. The results showed that the WTR granules significantly (p < 0.05) reduced dissolved P, Cu, and Zn, as well as total P, Cu, Pb, and Zn concentrations in stormwater runoff without signs of disintegration. No flooding or water ponding was observed during the implementation. Results suggest the WTR granules are an inexpensive, green filter material that can be used for retrofitting catch basins to remove phosphorus and heavy metals effectively.
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Metais Pesados , Poluentes Químicos da Água , Humanos , Fósforo , Resíduos Industriais , Poluentes Químicos da Água/análise , Chuva , Metais Pesados/análiseRESUMO
Over the past several decades, the value of drinking water treatment residuals (WTRs), a byproduct of the coagulation process during water purification, has been recognized in various environmental applications, including sustainable remediation of phosphorus (P)-enriched soils. Aluminum-based WTRs (Al-WTRs) are suitable adsorbent materials for P, which can be obtained and processed inexpensively. However, given their heterogeneous nature, it is essential to identify an easily analyzable chemical property that can predict the capability of Al-WTRs to bind P before soil amendment. To address this issue, thirteen Al-WTRs were collected from various geographical locations around the United States. The non-hazardous nature of the Al-WTRs was ascertained first. Then, their P adsorption capacities were determined, and the chemical properties likely to influence their adsorption capacities were examined. Statistical models were built to identify a single property to best predict the P adsorption capacity of the Al-WTRs. Results show that all investigated Al-WTRs are safe for environmental applications, and oxalate-extractable aluminum is a significant indicator of the P adsorption capacity of Al-WTRs (p-value = 0.0002, R2 = 0.7). This study is the first to report a simple chemical test that can be easily applied to predict the efficacy of Al-WTRs in binding P before their broadscale land application.
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Água Potável , Purificação da Água , Estados Unidos , Fósforo/química , Alumínio/química , Adsorção , Purificação da Água/métodos , SoloRESUMO
Per- and polyfluoroalkyl substances (PFAS) are a group of chemicals widely manufactured for industrial and commercial applications in the past decades due to their remarkable stability as well as hydrophobic and lipophobic nature. PFAS species have been recognized as emerging environmental contaminants of concern due to their toxicity and environmental persistence, thereby attracting intensive research seeking effective technologies for their removal from the environment. The objective of this review is to provide a thorough analysis of the biodegradation of PFAS in multiple environmental matrices and offer a future outlook. By discussing targeted PFAS species, degradation intermediates, degradation efficiencies, and microbial species, a comprehensive summary of the known microbial species and their degradation pathways are presented. The biodegradation pathways for different types of PFAS species are summarized in two major categories, biodegradation with and without the cleavage of C-F bond. Existing uncertainties and future research directions for PFAS biodegradation are provided.
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Fluorocarbonos , Poluentes Químicos da Água , Biodegradação Ambiental , Fluorocarbonos/análise , Poluentes Químicos da Água/análiseRESUMO
Although tea can be beneficial for our health, consuming excess trace elements in tea can be harmful. In this study, the carcinogenic and noncarcinogenic health risk for trace elements in tea influenced by the country of origin, tea type, and infusion process was assessed. Tea (Camellia sinensis) purchased from China, India, and the USA, including black and green tea, were analyzed for essential micronutrients (Cu, Se, and Zn) and nonessential trace elements (Ag, As, Ba, Cd, Cr, and Pb) in leaves and three types of infusions. The results showed that country of origin, tea type, and infusion process had a significant influence on the trace element contents in tea leaves and infusions, also on health risk. Country of origin had a significant influence on Ba, Cr, Pb, and Zn contents in tea leaves and on As, Ba, Cd, Cr, Pb, and Zn contents in tea infusions. Black tea had significantly higher (p < 0.05) Cr and Cu content in tea leaves than green tea, but only Cr content was significantly higher (p < 0.05) than that of green tea in tea infusion. The trace element contents were the highest in the first infusion and decreased as the number of infusion steps increased. The results showed that the consumption of tea infusion was not likely to cause noncarcinogenic risk. However, the carcinogenic risk for As was of concern. Our results indicate that avoiding drinking the first infusion can help to reduce both carcinogenic and noncarcinogenic health risks for trace elements.
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Camellia sinensis , Oligoelementos , Cádmio , Chumbo , Medição de Risco , Chá , Oligoelementos/análiseRESUMO
Biochar mediated pollutant removal is gaining attention because of high efficiency of the process. However, effective recycling avenues of the pollutant-saturated biochars are scarce in the knowledge base; while such materials can be a new source of long-range contamination. Therefore, potential of vermitechnology for eco-friendly recycling of pollutant-loaded biochar was assessed by using arsenic-saturated native (NBC) and exfoliated (EBC) biochars as feedstocks for the first time. Interestingly, the bioavailable arsenic fractions (water soluble and exchangeable) considerably reduced by 22-44 % with concurrent increment (~8-15 %) of the recalcitrant (residual and organic bound) fractions in the biochar-based feedstocks. Consequently, ~2-3 folds removal of the total arsenic was achieved through vermicomposting. The earthworm population growth (2.5-3 folds) was also highly satisfactory in the biochar-based feedstocks. The results clearly imply that Eisenia fetida could compensate the arsenic-induced stress to microbial population and greatly augmented microbial biomass, respiration and enzyme activity by 3-12 folds. Moreover, biochar-induced alkalinity was significantly neutralized in the vermibeds, which remarkably balanced the TOC level and nutrient (N, P, and K) availability particularly in EBC + CD vermibeds. Overall, the nutrient recovery potential and arsenic removal efficiency of vermitechnology was clearly exhibited in NBC/EBC + CD (12.5:87.5) feedstocks. Hence, it is abundantly clear that vermitechnology can be a suitable option for eco-friendly recycling of pollutant-saturated sorbing agents, like biochars.
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Arsênio , Poluentes do Solo , Carvão Vegetal , Nutrientes , Solo , Poluentes do Solo/análiseRESUMO
Acid mine drainage (AMD) is an acidic and metalliferous discharge that imposes oxidative stress on living things through bioaccumulation and physical exposure. The abandoned Tab-Simco mining site of Southern Illinois generates highly acidic AMD with elevated sulfate (SO4 2- ) and various metals. Vetiver grass (Chrysopogon zizanioides) is effective for the remediation of Tab-Simco AMD at both mesocosm and microcosm levels over extended periods. In this study, we conducted a proteomic investigation of vetiver shoots under short and long-term exposure to AMD. Our objective was to decipher the physiological responses of vetiver to the combined abiotic stresses of AMD (metal and low pH). Differential regulation was observed for longer-term (56 days) exposure to AMD, which resulted in 17 upregulated and nine downregulated proteins, whereas shorter-term (7 days) exposure led to 14 upregulated and 14 downregulated proteins. There were significant changes to photosynthesis, including upregulation of electron transport chain proteins for light-dependent reactions after 56 days, whereas differential regulation of enzymes relating to C4 carbon fixation was observed after 7 days. Significant changes in amino acid and nitrogen metabolism, including upregulation of ethylene and flavonoid biosynthesis, along with plant response to nitrogen starvation, were observed. Short-term changes also included upregulation of glutathione reductase and methionine sulfoxide reductase, whereas longer-term changes included changes in protein misfolding and ER-associated protein degradation for stress management and acclimation.
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Vetiveria , Ácidos , Biodegradação Ambiental , Mineração , ProteômicaRESUMO
Overuse of antibiotics has resulted in widespread contamination of the environment and triggered antibiotic resistance in pathogenic bacteria. Conventional wastewater treatment plants (WWTPs) are not equipped to remove antibiotics. Effluents from WWTPs are usually the primary source of antibiotics in aquatic environments. There is an urgent need for cost-effective, environment-friendly technologies to address this issue. Along with antibiotics, nutrients (nitrogen and phosphorus) are also present in conventional WWTP effluents at high concentrations, causing environmental problems like eutrophication. In this study, we tested vetiver grass in a plug flow reactor-based constructed wetland model in a greenhouse setup for removing antibiotics ciprofloxacin (CIP) and tetracycline (TTC), and nutrients, N and P, from secondary wastewater effluent. The constructed wetland was designed based on a previous batch reaction kinetics study and reached a steady-state in 7 days. The measured concentrations of antibiotics were generally consistent with the modeling predictions using first-order reaction kinetics. Vetiver grass significantly (p < 0.05) removed 93% and 97% of CIP and TTC (initial concentrations of 10 mg/L), simultaneously with 93% and 84% nitrogen and phosphorus, respectively. Results show that using vetiver grass in constructed wetlands could be a viable green technology for the removal of antibiotics and nutrients from wastewater.
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Eutrophication is caused by excess nitrate and other nutrient exported via stormwater runoff to surface waters, which is projected to increase as a result of climate change. Despite recent increases in the implementation of stormwater control measures (SCM), nutrient export has not abated, indicating poor or inconsistent removal capacities of SCM for nitrate. However, the cause of the variability is unclear. We show that both design and local climate can explain nitrate removal variability by critically analyzing data reported on the international BMP database for nitrate removal by four common types of SCM: bioretention cells, grass swales, media filters, and retention ponds. The relative importance of climate or design on nitrate removal depends on the SCM type. Nitrate removal in grass swales and bioretention systems is more sensitive to local climate than design specifications, whereas nitrate removal in the retention ponds is less sensitive to climate and more sensitive to design features such as vegetation and pond volume. Media filters without amendment have the least capacity compared to other SCM types surveyed, and their removal capacity was independent of the local climate. Adding amendments made up of carbon biomass, iron-based media, or a mixture of these amendments can significantly improve nitrate removal. The type of carbon biomass is also a factor since biochar does not appear to affect nitrate removal. This analysis can help inform the selection of SCM and modification of their design based on local and projected climate to maximize nitrate removal and minimize eutrophication.
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Nitratos , Chuva , Eutrofização , Nitrogênio , Óxidos de Nitrogênio , IncertezaRESUMO
The use of insensitive munitions such as 3-nitro-1,2,4-triazol-5-one (NTO) is rapidly increasing and is expected to replace conventional munitions in the near future. Various NTO treatment technologies are being developed for the treatment of wastewater from industrial munition facilities. This is the first study to explore the potential phytoremediation of industrial NTO-wastewater using vetiver grass (Chrysopogon zizanioides L.). Here, we present evidence that vetiver can effectively remove NTO from wastewater, and also translocated NTO from root to shoot. NTO was phytotoxic and resulted in a loss of plant biomass and chlorophyll. The metabolomic analysis showed significant differences between treated and control samples, with the upregulation of specific pathways such as glycerophosphate metabolism and amino acid metabolism, providing a glimpse into the stress alleviation strategy of vetiver. One of the mechanisms of NTO stress reduction was the excretion of solid crystals. Scanning electron microscopy (SEM), electrospray ionization mass spectrometry (ESI-MS), and Fourier-transform infrared spectroscopy (FTIR) analysis confirmed the presence of NTO crystals in the plant exudates. Further characterization of the exudates is in progress to ascertain the purity of these crystals, and if vetiver could be used for phytomining NTO from industrial wastewater.
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Vetiveria/metabolismo , Resíduos Industriais/análise , Nitrocompostos/metabolismo , Triazóis/metabolismo , Águas Residuárias/química , Biodegradação Ambiental , Metabolômica , Nitratos/metabolismo , Exsudatos de Plantas/análise , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Antibiotics have been widely used not only for the treatment and prevention of human infectious diseases but also to promote growth and prevent infections in farm animals. These antibiotics enter the environment via wastewater treatment plants, most of which cannot remove them. In addition to antibiotics, nutrients such as nitrogen (N) and phosphorus (P) also create major environmental pollution problems in surface water. Previously, we reported that vetiver grass [Chrysopogon zizanioides (L.) Roberty] successfully removed antibiotics from secondary wastewater effluent. In this study, our objective was to evaluate the potential of vetiver grass to remove two antibiotics, ciprofloxacin (CIP) and tetracycline (TTC), from wastewater in the presence of high N and P. Our results show that vetiver grass significantly (p < 0.05) removed antibiotics (60-94% CIP and 89-100% TTC) and nutrients (78-89% N and 71-97% P) from the secondary wastewater effluent. The removal of antibiotics dropped with increasing nutrient concentrations. The removal efficiency was mainly affected by the presence of N rather than P in the secondary wastewater effluent. The presence of CIP induced more stress on vetiver grass compared to TTC. Vetiver also removed total organic carbon (48-73%) and chemical oxygen demand (73-82%), but their removal was also affected by the nutrient content in the secondary wastewater effluent.
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Vetiveria , Antibacterianos , Biodegradação Ambiental , Ciprofloxacina , Nutrientes , Águas ResiduáriasRESUMO
Persistence of antibiotics in soil and aquatic ecosystem is the primary reason for the emergence of antimicrobial resistant microorganisms. After consumption, antibiotics are poorly retained in our body, and a major fraction is excreted out. These bioactive compounds end up in wastewater. The routine treatment practiced by the conventional wastewater treatment plants does not remove the entire load of antibiotics. Cost-effective and environment-friendly treatment technologies need to be developed to address this issue. Vetiver system is being adapted throughout the world due to its removal capacity and high tolerance toward several toxic organic and inorganic pollutants. In this study, we investigated the potential of vetiver (Chrysopogon zizanioides), a fast-growing, perennial grass capable of growing in a hydroponic setup, to remove two widely prescribed antibiotics, ciprofloxacin (CIP) and tetracycline (TTC) from secondary wastewater effluent. Significant (p < 0.05) removal of antibiotics and nutrients (N & P) by vetiver grass from secondary wastewater effluent was observed within 30 days. Vetiver grass removed more than 90% antibiotics from secondary wastewater matrix. In addition to antibiotics, vetiver grass also removed nitrate (>40%), phosphate (>60%), total organic carbon (>50%), and chemical oxygen demand (>40%) from secondary wastewater effluent.
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Vetiveria , Poluentes do Solo , Antibacterianos , Biodegradação Ambiental , Ecossistema , Nutrientes , Águas ResiduáriasRESUMO
Blueberry anthocyanins have the ability to efficiently reach the GI tract and exhibit a broad range of biochemical effects. In the context of inflammatory bowel disease (IBD), they remain a promising complement to current IBD treatments. Here, we investigated the anti-inflammatory and antioxidant capabilities of Highbush blueberries in-vitro on two normal colon epithelial cell lines, NCM 356 and CCD 841 CoN using fluorescent microscopy and flow cytometry following stimulation with a pro-inflammatory cytokine cocktail. Treatment with blueberry extract revealed a significant decrease in nuclear and cytoplasmic generated reactive oxygen species (ROS) compared to controls. Additionally, the blueberry extract increased cell viability following treatment with the pro-inflammatory cytokine cocktail. A comparison with previous report on rice callus suspension culture (RCSC) revealed opposing trend with reference to the levels of nuclear and cytoplasmic ROS. It is likely that blueberry extract and RCSC employ different players and pathways to mitigate inflammation.