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1.
Sci Rep ; 14(1): 1586, 2024 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-38238408

RESUMEN

Renewable resources have stood out as raw materials in producing biofuels. This study aimed to evaluate the parameters of alcohol transesterification (ethanol and methanol) and localization of collection of aquatic macrophyte Eichhornia crassipes (Mart.) Solms in the production of biodiesel by in situ transesterification. E. crassipes was collected in Dourados and Corumbá (Brazil) municipalities. The fatty acid ester composition of the biodiesel was characterized and quantified by gas chromatography. The biodiesel properties were estimated using the BiodieselAnalyzer© program prediction. The ethyl transesterification resulted in higher yields, but the localization of collection was the most relevant parameter in biodiesel production according to the Permutation Multivariate Analysis of Variance. The simulation and comparison of the physical-chemical properties of E. crassipes biodiesel and BD 100 (commercial biodiesel) were promising for commercial application.


Asunto(s)
Eichhornia , Biocombustibles , Eichhornia/química , Esterificación , Etanol , Metanol
2.
Environ Res ; 231(Pt 1): 116074, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37150391

RESUMEN

The starch is one of the most essential food stuff and serves as a raw material for number of food products for the welfare of human. During the production process enormous volume of effluents are being released into the environment. In this regard, this study was performed to evaluate the physicochemical traits of Manihot esculenta processing effluent and possible sustainable approach to treat this issue using Eichhornia crassipes based biochar. The standard physicochemical properties analysis revealed that the most the parameters (EC was recorded as 4143.17 ± 67.12 mhom-1, TDS: 5825.62 ± 72.14 mg L-1, TS: 7489.21 ± 165.24 mg L-1, DO: 2.12 ± 0.21 mg L-1, BOD 2673.74 ± 153.53 mg L-1, COD: 6672.66 ± 131.21 mg L-1, and so on) were beyond the permissible limits and which can facilitate eutrophication. Notably, the DO level was considerably poor and thus can support the eutrophication. The trouble causing E. crassipes biomass was used as raw material for biochar preparation through pyrolysis process. The temperature ranging from 250 to 350 °C with residence time of 20-60 min were found as suitable temperature to provide high yield (56-33%). Furthermore, 10 g L-1 concentration of biochar showed maximum pollutant adsorption than other concentrations (5 g L-1 and 15 g L-1) from 1 L of effluent. The suitable temperature required to remediate the pollutants from the effluent by biochar was found as 45 °C and 35 °C at 10 g L-1 concentration. These results conclude that at such optimized condition, the E. crassipes effectively adsorbed most of the pollutants from the M. esculenta processing effluent. Furthermore, such pollutants adsorption pattern on biochar was confirmed by SEM analysis.


Asunto(s)
Eichhornia , Contaminantes Ambientales , Manihot , Contaminantes Químicos del Agua , Humanos , Eichhornia/química , Adsorción , Contaminantes Químicos del Agua/análisis
3.
Sci Rep ; 13(1): 1824, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36725877

RESUMEN

Water quality index (WQI) of Narora channel and health of endemic fish Bagarius bagarius and plant Eichhornia crassipes, district Bulandshahar, Uttar Pradesh, India were studied. Among the physicochemical properties of water, pH, D.O, Cr, Fe, Ni, and Cd were above the recommended standards. These factors lead to high WQI (4124.83), indicating poor quality and not suitable for drinking and domestic usage. In fish tissues, the highest metal load was reported in the liver (58.29) and the lowest in the kidney (33.73). Heavy metals also cause a lowering of condition indices. As expected, decreased serum protein (- 63.41%) and liver glycogen (- 79.10%) were recorded in the exposed fish. However, blood glucose (47.22%) and serum glycogen (74.69%) showed elevation. In the plant, roots (21.50) contained the highest, and leaves (16.87) had the lowest heavy metal load. Bioaccumulation factor (BAF) > 1, indicates hyperaccumulation of all metals. E. crassipes roots showed the highest translocation factor (TF) > 1 for Ni (1.57) and Zn (1.30). The high mobility factor (MF) reflected the suitability of E. crassipes for phytoextraction of Mn, Cd, Zn, Fe, Ni, and Cu. Moreover, Bagarius sp. consumption could not pose any non-cancer risk. Although, lower cancer risk can be expected from Ni and Cr.


Asunto(s)
Eichhornia , Metales Pesados , Contaminantes Químicos del Agua , Biomarcadores Ambientales , Eichhornia/química , Cadmio , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Metales Pesados/toxicidad , Metales Pesados/análisis , Plantas , Medición de Riesgo , Monitoreo del Ambiente
4.
Molecules ; 27(19)2022 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-36234979

RESUMEN

The discharge of large amounts of effluents contaminated with gentian violet (GV) and phenol red (PR) threatens aquatic flora and fauna as well as human health, which is why these effluents must be treated before being discarded. This study seeks the removal of dyes, using water lily (Eichhornia crassipes) as an adsorbent with different pretreatments. PR and GV were analyzed by a UV-visible spectrophotometer. Equilibrium experimental data showed that Freundlich is the best model to fit PR and SIPS for GV, showing that the adsorption process for both dyes was heterogeneous, favorable, chemical (for GV), and physical (for PR). The thermodynamic analysis for the adsorption process of both dyes depends directly on the increase in temperature and is carried out spontaneously. The Pseudo first Order (PFO) kinetic model for GV and PR is the best fit for the dyes having an adsorption capacity of 91 and 198 mg/g, respectively. The characterization of the materials demonstrated significant changes in the bands of lignin, cellulose, and hemicellulose, which indicates that the functional groups could participate in the capture of the dyes together with the electrostatic forces of the medium, from which it be concluded that the adsorption process is carried out by several mechanisms.


Asunto(s)
Eichhornia , Contaminantes Químicos del Agua , Adsorción , Aniones , Biomasa , Cationes , Celulosa/química , Colorantes/química , Eichhornia/química , Violeta de Genciana/química , Humanos , Concentración de Iones de Hidrógeno , Cinética , Lignina , Fenolsulfonftaleína , Termodinámica , Contaminantes Químicos del Agua/química
5.
Chemosphere ; 304: 135293, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35718030

RESUMEN

Azithromycin (AZIM) is considered as one of the most frequently prescribed antibiotics (ABs) in the world by medical professionals. This study explored, two novel, cheap and environmentally beneficial adsorbents i.e., alkali treated water hyacinth powder (AT-WHP) and graphene oxide-water hyacinth-polyvinyl alcohol (GO-WH-PVA) composite, fabricated from water hyacinth (Eichhornia crassipes) waste to remediate AZIM from wastewater. Biosorption experiments were performed by batch and packed-bed column studies and the adsorbents were characterized using various instrumental methods. The morpho-chemical profile of the adsorbents suggested noteworthy AZIM adsorption. AZIM adsorption data can be reasonably explained by pseudo second order (PSO) kinetic model with maximum regression coefficient (R2 > 0.99) and lowest Marquardt's present standard deviation (MPSD) and root mean squared error (RMSE) values. The isotherm models recommended Langmuir and Temkin to be the best-fitted, providing highest regression coefficient and lowest error values. Conferring to Langmuir model, the theoretical highest adsorption potentials (qmax) were accounted to be 244.498 and 338.115 mg/g for AT-WHP and GO-WH-PVA, correspondingly, very close to experimental values (qe, exp). AZIM adsorption processes were governed by the chemisorption mechanisms. The adsorbents had excellent regeneration potential and could be reused several times. In order to scale-up application of the adsorbents, performance of a 100 L packed-bed reactor was assessed and a breakthrough time of adsorption for GO-WH-PVA was 15 min in 5000 mg/L AZIM concentration. Thus, the absorbents synthesized in this study can be considered highly effective at removal of AZIM from wastewater.


Asunto(s)
Eichhornia , Contaminantes Químicos del Agua , Adsorción , Álcalis , Antibacterianos/química , Eichhornia/química , Cinética , Aguas Residuales/química , Contaminantes Químicos del Agua/química
6.
Ecotoxicol Environ Saf ; 221: 112415, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34171691

RESUMEN

In order to understand the mechanisms of arsenic (As) accumulation and detoxification in aquatic plants exposed to different As species, a hydroponic experiment was conducted and the three aquatic plants (Hydrilla verticillata, Pistia stratiotes and Eichhornia crassipes) were exposed to different concentrations of As(III), As(V) and dimethylarsinate (DMA) for 10 days. The biomass, the surface As adsorption and total As adsorption of three plants were determined. Furthermore, As speciation in the culture solution and plant body, as well as the arsenate reductase (AR) activities of roots and shoots, were also analyzed. The results showed that the surface As adsorption of plants was far less than total As absorption. Compared to As(V), the plants showed a lower DMA accumulation. P. stratiotes showed the highest accumulation of inorganic arsenic but E. crassipes showed the lowest at the same As treatment. E. crassipes showed a strong ability to accumulate DMA. Results from As speciation analysis in culture solution showed that As(III) was transformed to As(V) in all As(III) treatments, and the oxidation rates followed as the sequence of H. verticillata>P. stratiotes>E. crassipes>no plant. As(III) was the predominant species in both roots (39.4-88.3%) and shoots (39-86%) of As(III)-exposed plants. As(V) and As(III) were the predominant species in roots (37-94%) and shoots (31.1-85.6%) in As(V)-exposed plants, respectively. DMA was the predominant species in both roots (23.46-100%) and shoots (72.6-100%) in DMA-exposed plants. The As(III) contents and AR activities in the roots of P. stratiotes and in the shoots of H. verticillata were significantly increased when exposed to 1 mg·L-1 or 3 mg·L-1 As(V). Therefore, As accumulation mainly occurred via biological uptake rather than physicochemical adsorption, and AR played an important role in As detoxification in aquatic plants. In the case of As(V)-exposed plants, their As tolerance was attributed to the increase of AR activities.


Asunto(s)
Araceae , Arseniato Reductasas/metabolismo , Arsénico , Ácido Cacodílico , Eichhornia , Hydrocharitaceae , Proteínas de Plantas/metabolismo , Contaminantes Químicos del Agua , Adsorción , Araceae/química , Araceae/metabolismo , Arsénico/química , Arsénico/metabolismo , Ácido Cacodílico/química , Ácido Cacodílico/metabolismo , Eichhornia/química , Eichhornia/metabolismo , Hydrocharitaceae/química , Hydrocharitaceae/metabolismo , Hidroponía , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Brotes de la Planta/química , Brotes de la Planta/metabolismo , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo
7.
J Nat Prod ; 84(6): 1772-1779, 2021 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-34033480

RESUMEN

Induced water hyacinth with purple roots (PRWH) exerts a significant inhibitory effect on the growth of blue-green algae. Interestingly, its chemical constituents differ from those of wild-type water hyacinth and have not yet been reported. This study aimed to explore the chemical constituents of PRWH and its bioactive components serving as allelopathic agents against blue-green algae. Phytochemical investigation of the bioactive ethyl acetate fraction of a crude methanol extract from PRWH led to the isolation of 56 compounds, including 11 new phenylphenalene derivatives. The structures of these compounds were elucidated by comprehensive analyses through NMR, HRMS, and X-ray techniques. Bioactivity evaluation against Microcystis aeruginosa indicated that compounds 7, 12, 15, 37, 39, 45, and 47 potently inhibited blue-green algae growth.


Asunto(s)
Alelopatía , Eichhornia/química , Microcystis/efectos de los fármacos , Extractos Vegetales/farmacología , China , Estructura Molecular , Fitoquímicos/farmacología , Raíces de Plantas/química
8.
Int Microbiol ; 24(3): 337-349, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33683516

RESUMEN

Cellulose is the cheapest, natural, renewable organic substance that is used as a carbon source in various fields. Water hyacinth, an aquatic plant rich in cellulose, is often used as a raw material in fuel production. However, natural cellulase can be hardly used in industrial production on account of its low thermal stability and activity. In this study, a metagenomic library was constructed. Then, a new cellulase gene, cel1029, was screened by Congo red staining and expressed in the prokaryotic system. Enzymatic properties of Cel1029 were explored, including optimum temperature and pH, thermal and pH stability, and tolerance against organic solvents, metal ions, and salt solutions. Finally, its ability of degrading water hyacinth was identified and evaluated. Cel1029 displayed high homology with endoglucanase in the glycoside hydrolase family 5 (GH5) and had high stability across a broad temperature range. More than 86% of its enzymatic activities were retained between 4 and 60 °C after 24 h of incubation. Single-factor analysis and orthogonal design were further conducted to determine the optimal conditions for the highest reducing sugar yield of water hyacinth. Interestingly, Cel1029 efficiently transformed water hyacinth with a reducing sugar yield of 430.39 mg/g in 22 h. These findings may open the door for significant industrial applications of a novel GH5 cellulase (NCBI Reference Sequence: MK051001, Cel1029) and help identify more efficient methods to degrade cellulose-rich plants.


Asunto(s)
Celulasa/genética , Celulasa/aislamiento & purificación , Celulasa/metabolismo , Celulosa/metabolismo , Eichhornia/química , Secuencia de Aminoácidos , Clonación Molecular , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Metagenómica/métodos , Filogenia , Microbiología del Suelo , Temperatura
9.
PLoS One ; 15(8): e0237258, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32756605

RESUMEN

Aquatic weeds such as muskgrass (Chara spp.), water hyacinth (Eichhornia crassipes), water lettuce (Pistia stratiotes), hydrilla (Hydrilla verticillate), filamentous algae (Lyngbya wollei), and duckweed (Lemna minor) thrive in farm canals within the Everglades Agricultural Area of South Florida. Their presence, particularly during the summer months is an environmental concern with regards to water quality, in addition to being a nuisance because of their ability to multiply and spread rapidly in open waters causing restricted drainage/irrigation flow and low dissolved oxygen levels. Chemical control is effective but can have undesirable off-target effects, so reduced herbicide use is desirable. Hence, need exists to discover ways in which these weeds could be best managed or utilized. The objective of this research was to evaluate the allelopathic effect of these weeds to determine their use as potential biopesticides. Six aqueous extracts were tested against 100 bacterial strains isolated from plants and soil to evaluate their antimicrobial activity. These extracts were also used to determine their insecticidal and antifeedant effects on fall armyworm (FAW, Spodoptera frugiperda). Both extracts and powder form of the aquatic weeds were tested for their herbicidal activity towards seed germination and growth of three common terrestrial weed species. At a dilution of 1:100 and 1:1,000, none of the aquatic weeds inhibited in-vitro growth of the bacterial strains, with one exception (filamentous algae extract at 1:100 reduced growth of one bacterial isolate by 54%). Water lettuce reduced the survival rate of FAW by 14% while hydrilla and duckweed caused 11% and 9% reduction of FAW growth, respectively. Powdered duckweed inhibited the growth of nutsedge by 41%, whereas filamentous algae powder and extract reduced germination of amaranth by 20% and 28%, respectively. Harvesting these weeds and converting them into useable compounds could not only eliminate the in situ farm canal and water quality problems but also result in development of new soil amendments or biopesticides.


Asunto(s)
Antibacterianos/toxicidad , Agentes de Control Biológico/toxicidad , Malezas/química , Agricultura , Animales , Antibacterianos/química , Bacterias/efectos de los fármacos , Agentes de Control Biológico/química , Cianobacterias/química , Eichhornia/química , Hydrocharitaceae/química , Insecticidas/química , Insecticidas/toxicidad , Plantas/microbiología , Microbiología del Suelo , Spodoptera/efectos de los fármacos
10.
ScientificWorldJournal ; 2020: 3452172, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32724301

RESUMEN

Water hyacinths pose serious challenges to humanity and the environment. Considering the enormity of the menace associated with the growth and spread of the plant and the difficulty in achieving a single, generally acceptable control method, it is becoming increasingly imperative to explore the potentials of the plant. New water hyacinth-related articles are regularly being published. Recently published articles about the plant were accessed, and the information in these articles is presented in the context of the pros and cons of the plant. Some of the benefits that can be derived from the plant include biogas and biofuel production, medicinal functions, vermicomposting, compost production, and bioremediation. However, clogging of waterways, obstruction of water transportation, and fishing activities; breeding grounds for pests and diseases; and reduction of water quality, loss of biodiversity, and economic downturn in areas invaded by the plant are problems associated with it. The peculiarity in the invasiveness of each situation should determine whether or not the growth of the plant is a problem, especially if the opportunity to harness the potentials of the plant exists. There are three major methods for controlling the plants when control becomes inevitable: mechanical, chemical, and biological. To achieve the best control, integrating two or more control methods is advised.


Asunto(s)
Alimentación Animal , Biocombustibles , Compostaje , Eichhornia/crecimiento & desarrollo , Malezas/crecimiento & desarrollo , Animales , Biodegradación Ambiental , Biodiversidad , Agentes de Control Biológico , Vectores de Enfermedades , Eichhornia/química , Eichhornia/clasificación , Explotaciones Pesqueras , Humanos , Plantas Medicinales/química , Factores Socioeconómicos , Calidad del Agua
11.
Carbohydr Polym ; 240: 116202, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32475542

RESUMEN

In this study, Eichhornia crassipes (EC) was exposed to Chemical modification using citric acid to enhancement adsorption capacity and form Modified Nano Cellulose Crystalline (MNCC) powders and comparison study was performed to remove two different dyes as Reactive blue 21 (RB21) and Crystal violet (CV). Characterization of MNCC was investigated by X-Ray Diffraction analysis (XRD), Fourier Transform infrared spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA), Dynamic Light Scatting (DLS) and Transmission electron microscopy (TEM) as well as Scanning Electron Microscopy (SEM) and results, prove that MNCC is in Nano scale and has crystalline structure as well as ester form. Examine parameters such as adsorbent dose (0.1-1.00 g/40 mL), initial pH (1-10), contact time (5-120 min) and initial concentration dyes (5-10 ppm). Among the three isotherm models (Langmuir, Freundlich, and Temkin), the equilibrium adsorption confirmed and fitted well to the Langmuir isotherm model. Kinetic study showed agreement the pseudo-second-order kinetic model and Intraparticle diffusion model.


Asunto(s)
Celulosa/química , Ácido Cítrico/química , Colorantes/aislamiento & purificación , Eichhornia/química , Violeta de Genciana/aislamiento & purificación , Metaloporfirinas/aislamiento & purificación , Adsorción , Cinética , Termodinámica , Contaminantes Químicos del Agua/aislamiento & purificación
12.
Bull Environ Contam Toxicol ; 104(4): 411-417, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32152684

RESUMEN

Eutrophication and metal contamination are the principal pollution problem for almost all inland lakes in world. Phytoremediation is one of the viable solutions for this concern. The present study analysed the concentration and distribution of six metals (cadmium, chromium, copper, nickel, lead and zinc) in sediment and macrophyte samples of Varthur Lake, Bangalore. Higher concentrations of studied metals in sediment were observed at the inlet and north shoreline regions of the lake. Alternanthera philoxeroides and Eichhornia crassipes accumulated higher concentration of metals than other species. Accumulation of metals in the sediment were Cu > Zn > Cr > Ni > Pb > Cd, whereas the order in macrophyte samples was Cu > Zn > Cr > Pb > Ni > Cd. Bioconcentration factor (BCF) and translocation factor (TF) of metals in macrophytes revealed metal pollution could be remediated through phytoextraction and phytostabilization.


Asunto(s)
Eichhornia/química , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Lagos/química , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Bioacumulación , Biodegradación Ambiental , Eichhornia/metabolismo , India
13.
Environ Monit Assess ; 192(2): 141, 2020 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-31982980

RESUMEN

Cellulose emerges as an alternative for the treatment of water contaminated with heavy metals due to its abundant biomass and its proven potential in the adsorption of pollutants. The aquatic plant Eichhornia crassipes is an option as raw material in the contribution of cellulose due to its enormous presence in contaminated wetlands, rivers, and lakes. The efficiency in the removal of heavy metals is due to the cation exchange between the hydroxyl groups and carboxyl groups present in the biomass of E. crassipes with heavy metals. Through different chemical and physical transformations of the biomass of E. crassipesThe objective of this review article is to provide a discussion on the different mechanisms of adsorption of the biomass of E. crassipes to retain heavy metals and dyes. In addition to estimating equilibrium, times through kinetic models of adsorption and maximum capacities of this biomass through equilibrium models with isotherms, in order to design one biofilter for treatment systems on a larger scale represented the effluents of a real industry.


Asunto(s)
Eichhornia , Metales Pesados , Contaminantes Químicos del Agua , Adsorción , Eichhornia/química , Monitoreo del Ambiente , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua
14.
J Hazard Mater ; 382: 121067, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31476719

RESUMEN

This work describes a simple and sensitive method for the simultaneous isolation, enrichment, identification and quantitation of selected antiretroviral drugs; emtricitabine, tenofovir disoproxil and efavirenz in aqueous samples and plants. The analytical method was based on microwave extraction and hollow fibre liquid phase microextraction technique coupled with ultra-high pressure liquid chromatography-high resolution mass spectrometry. A multivariate approach via a half-fractional factorial design was used focusing on six factors; donor phase pH, acceptor phase HCl concentration, extraction time, stirring rate, supported liquid membrane carrier composition and salt content. The optimal enrichment factors for emtricitabine, tenofovir disoproxil and efavirenz from aqueous phase were 78, 111 and 24, respectively. The analytical method yielded recoveries in the range of 86 to 111%, and quantitation limits for emtricitabine, tenofovir disoproxil and efavirenz in wastewater were 0.033, 0.10 and 0.53 µg L-1, respectively. The drugs were detected in most samples with concentrations up to 37.6 µg L-1 recorded for efavirenz in wastewater effluent. Roots of the water hyacinth plant had higher concentrations of the investigated drugs ranging from 7.4 to 29.6 µg kg-1. Overall, hollow fibre liquid phase microextraction proved to be an ideal tool for isolating and pre-concentrating the selected antiretroviral drugs from environmental samples.


Asunto(s)
Antirretrovirales/análisis , Benzoxazinas/análisis , Emtricitabina/análisis , Tenofovir/análisis , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis , Alquinos , Cromatografía Líquida de Alta Presión , Ciclopropanos , Eichhornia/química , Monitoreo del Ambiente , Microextracción en Fase Líquida , Raíces de Plantas/química , Espectrometría de Masas en Tándem
15.
Int J Biol Macromol ; 145: 64-76, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31874270

RESUMEN

The utilization from biomass feedstocks to fabricate the advanced nanomaterials has greatly attracted a great interest due to their low cost and sustainability. This work aimed to explore a simple way to prepare cellulose nanofibers using water-based approach via mechanical defibrillation. Cellulose fibers were first extracted from water hyacinth towards chemical treatments and then mechanically disintegrated as a function of defibrillation cycles. The morphologies, thermal stabilities, physical properties, and rheological characteristics of the micro- and nanofibers were demonstrated. It was found that the obtained nanofibers having a diameter of 5-50 nm and were successfully prepared within 10 defibrillation cycles. Even though longer defibrillation cycles greatly provided higher water retention value and specific surface area, a gradual decrease in crystallinity index, thermal degradation temperatures, and degree of polymerization was also observed. Based on the rheological properties, the storage modulus and steady viscosity of the as-prepared nanofibers suspension increased significantly as a function of defibrillation, resulting in a gel-like structure with a shear-thinning behavior. Additionally, the rheological parameters of the obtained nanofibers estimated using a Herschel-Bulkley model were more accurate than that estimated using a Bingham-Plastic model. The obtained nanofibers could be used as a prime candidate for many potential applications.


Asunto(s)
Celulosa/química , Eichhornia/química , Nanofibras/química , Agua/química , Biomasa , Reología/métodos , Suspensiones/química , Temperatura , Viscosidad
16.
Environ Sci Pollut Res Int ; 26(35): 35779-35786, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31705409

RESUMEN

The effects of eutrophication on the growth and phenotypic performance of macrophytes have been widely studied. Experimental evidence suggests that an increase in the water nutrient level would promote the performance of several invasive free-floating macrophytes. However, few studies have focused on how a shift in water nutrient (nitrogen and phosphorus) stoichiometric regimes may influence the performance of invasive free-floating macrophytes. In the present study, two exotic invasive plant species, free-floating Eichhornia crassipes and Pistia stratiotes, were subjected to different water nutrient stoichiometric regimes, and their phenotypic performance was studied. We found that the two species converged in several resource use traits and diverged in lateral root length. This implied that their similarities in fitness-correlated traits and their underwater niche differentiation probably contribute to their stable coexistence in the field. Additionally, the eutrophic conditions in the different N:P regimes scarcely altered the performance of both species compared to their performance in the oligotrophic condition. Based on previous studies, we predicted that moderate eutrophication with slight overloading of nitrogen and phosphorus would not improve the performance of several invasive free-floating plants and thus would scarcely alter the invasive status of these species. However, moderate eutrophication may cause other problems, such as the growth of phytoplankton and algae and increased pollution in the water.


Asunto(s)
Araceae/química , Eichhornia/crecimiento & desarrollo , Eutrofización/fisiología , Nitrógeno/análisis , Fósforo/análisis , Fitoplancton/química , Contaminantes Químicos del Agua/análisis , China , Eichhornia/química , Especies Introducidas , Nitrógeno/química , Nutrientes , Fósforo/química , Agua
17.
Environ Sci Pollut Res Int ; 26(33): 34345-34356, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31428965

RESUMEN

Fluoroquinolones (FQs) occur broadly in natural media due to its extensive use, and it has systematic effects on our ecosystem and human immunity. In this study, long-root Eichhornia crassipes was reclaimed as a multi-functional activated carbon (MFAC) to remove fluoroquinolones (FQs) from contaminated water. To get insight into the adsorption mechanism, multiple measurements, including FTIR and XPS analyses, were employed to investigate the adsorption processes of ciprofloxacin and norfloxacin as well as the experiments of effect of exogenous factors on adsorption performances. The results confirmed that the adsorption of FQs by MFAC was mainly attributed to the electrostatic interaction, hydrogen bond interaction, and electronic-donor-acceptor (EDA) interaction. In addition, the kinetics and thermodynamics experiments demonstrated that the MFAC possessed great adsorption performance for FQs. According to the Langmuir model, the saturated adsorption capacities exceeded 145.0 mg/g and 135.1 mg/g for CIP and NOR at 303.15 K, respectively. The column experiments were conducted to explore the application performance of MFAC on the advanced treatment of synthetic water at different flow rates and bed depths. The adsorption capacity of CIP on MFAC was estimated by the Thomas models and the bed-depth service time (BDST) models, reaching 127.56 mg/g and 11,999.52 mg/L, respectively. These results also provide a valid approach for the resource recycling of the redundant long-root Eichhornia crassipes plants. Graphical abstract.


Asunto(s)
Carbón Orgánico/química , Eichhornia/química , Fluoroquinolonas/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Antiinfecciosos , Ciprofloxacina , Ecosistema , Fluoroquinolonas/análisis , Humanos , Cinética , Norfloxacino , Reciclaje , Termodinámica , Agua , Contaminantes Químicos del Agua/análisis
18.
Environ Sci Pollut Res Int ; 26(27): 28361-28371, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31372953

RESUMEN

Aging effects play a crucial role in determining applications of green-synthesised iron-based nanoparticles in wastewater treatment from laboratory scale to practical applications. In this study, iron-based nanoparticles (Ec-Fe-NPs) were synthesised using the extract of Eichhornia crassipes and ferric chloride. Scanning electron microscopy (SEM) revealed that the fresh Ec-Fe-NPs were spherical and had a narrow particle size range (50 to 80 nm). X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) demonstrated that the Ec-Fe-NPs were mainly amorphous in nature and consisted of Fe0, FeO, Fe2O3 and Fe3O4. As they aged, the particle size of the liquid Ec-Fe-NPs gradually increased and then tended to stabilise. Ec-Fe-NPs that were aged for 28 days were only 19% less efficient than fresh material at removing Cr(VI). Extracts aged up to 28 days were also tested, and their antioxidant capacity was found to be 15.4% lower than that of the fresh extracts. Furthermore, the removal efficiency of Cr(VI) using iron-based nanoparticles synthesised with the aged extracts was 67.2%. Finally, the active components of the extracts, which were responsible for the reactivity and stability of the iron-based nanoparticles, were identified by liquid chromatography-mass spectrometry. Overall, green-synthesised iron-based nanoparticles show promise for Cr(VI) removal from wastewater in practical applications.


Asunto(s)
Cloruros/química , Eichhornia/química , Compuestos Férricos/química , Compuestos de Hierro/síntesis química , Nanopartículas del Metal/química , Extractos Vegetales/química , Aguas Residuales/análisis , Compuestos de Hierro/química , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Espectroscopía de Fotoelectrones , Difracción de Rayos X
19.
Artículo en Inglés | MEDLINE | ID: mdl-31443402

RESUMEN

Sorption is widely used for the removal of toxic heavy metals such as hexavalent chromium (Cr(VI)) from aqueous solutions. Green sorbents prepared from biomass are attractive, because they leverage the value of waste biomass and reduce the overall cost of water treatment. In this study, we fabricated biochar (BC) adsorbent from the biomass of water hyacinth (Eichhornia crassipes), an invasive species in many river channels. Pristine BC was further modified with nanoscale zero-valent iron (nZVI) and stabilized with chitosan (C) to form C-nZVI-BC. C-nZVI-BC adsorbent showed high hexavalent chromium sorption capacity (82.2 mg/g) at pH 2 and removed 97.34% of 50 mg/L Cr(VI) from aqueous solutions. The sorption capacity of chitosan-nZVI-modified biochar decreased while increasing the solution pH value and ionic strength. The results of a sorption test indicated that multiple mechanisms accounted for Cr(VI) removal by C-nZVI-BC, including complexation, precipitation, electrostatic interactions, and reduction. Our study suggests a way of adding value to biomass waste by considering environmental treatment purposes.


Asunto(s)
Carbón Orgánico/química , Quitosano/química , Cromo/análisis , Eichhornia/química , Hierro/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
20.
Int J Biol Macromol ; 137: 119-125, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31252021

RESUMEN

The cellulose microfibers (CMF) from water hyacinth (WH) fiber as a filler in sago starch (SS) biocomposites was investigated. The CMF was isolated by pulping, bleaching and acid hydrolysis methods. The addition of CMF in sago matrix was varied i.e. 0, 5, 10, 15 and 20 wt%. Biocomposites were made by using solution casting and glycerol as a plasticizer. The biocomposites were also determined by tensile test, FTIR, X-Ray, thermogravimetric, SEM, and soil burial tests. The results show that the SS15CMF sample has the highest tensile strength of 10.23 MPa than those other samples. Scanning Electron Microscope (SEM) images show that the strong interaction was formed between CMF WH and matrix. Fourier Transform Infra-red (FTIR) indicated that the functional group of biocomposites was a hydrophilic cluster. The addition of CMF WH in sago starch biocomposites lead to the moisture barrier, crystallinity, and thermal stability increased; it is due to the pure sago starch film was more rapidly degraded than its biocomposites.


Asunto(s)
Arecaceae/química , Celulosa/química , Eichhornia/química , Almidón/química , Hidrólisis , Ensayo de Materiales , Plastificantes , Suelo/química , Temperatura , Resistencia a la Tracción
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