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1.
Analyst ; 149(17): 4351-4362, 2024 Aug 19.
Article de Anglais | MEDLINE | ID: mdl-39005217

RÉSUMÉ

Paper-based microfluidics combined with potentiometric measurement has emerged as an attractive approach for detecting various chemical ionic moieties. Detection of heavy metal ions, using paper substrates as solution sampling and delivery systems remains challenging despite efforts to introduce several physico-chemical paper substrate modifications to stop adsorption of ions onto the paper substrates. This study quantitatively investigates the adsorption of heavy metal ions on the paper substrates during paper-based potentiometric measurements and explains the super-Nernstian response of potentiometric sensors through local depletion of heavy metal ions from the solution. Consequently, based on the investigated ion adsorption, a corrective potential protocol was established for the electrodes coupled with paper-based solution sampling by predicting interference free sensor response from paper-based measurement. Furthermore, the ion adsorption was also recorded for mixed metal ion solutions to understand competitive primary/interfering ions adsorption onto the paper substrates and establish corrective measures to predict interference free sensor response. In this method, no modifications of the paper substrates are necessary before actual potentiometric measurements. The proposed corrective protocol allows prediction of sensor response based on the paper-based solution sampling potentiometric measurement, providing a simple methodological approach based on correction of potential readout of the potentiometric sensor, thus completely resigning from the need of modifying paper substrate for measurements of heavy metal ions.

2.
J Environ Sci (China) ; 146: 91-102, 2024 Dec.
Article de Anglais | MEDLINE | ID: mdl-38969465

RÉSUMÉ

In this study, a gravity-driven membrane (GDM) filtration system and hydroponic system (cultivating basil and lettuce) were combined for nutrient recovery from primary municipal wastewater. The GDM system was optimized by increasing the periodic air sparging flow rate from 1 to 2 L/min (∼15 hr per 3-4 days), resulting in a ∼52% reduction of irreversible fouling. However, the total fouling was not alleviated, and the water productivity remained comparable. The GDM-filtrated water was then delivered to hydroponic systems, and the effects of hydroponic operation conditions on plant growth and heavy metal uptake were evaluated, with fertilizer- and tap water-based hydroponic systems and soil cultivation system (with tap water) for comparison. It was found that (i) the hydroponic system under batch mode facilitated to promote vegetable growth with higher nutrient uptake rates compared to that under flow-through feed mode; (ii) a shift in nutrient levels in the hydroponic system could impact plant growth (such as plant height and leaf length), especially in the early stages. Nevertheless, the plants cultivated with the GDM-treated water had comparable growth profiles to those with commercial fertilizer or in soils. Furthermore, the targeted hazard quotient levels of all heavy metals for the plants in the hydroponic system with the treated water were greatly lower than those with the commercial fertilizer. Especially, compared to the lettuce, the basil had a lower heavy metal uptake capability and displayed a negligible impact on long-term human health risk, when the treated water was employed for the hydroponic system.


Sujet(s)
Filtration , Culture hydroponique , Nutriments , Élimination des déchets liquides , Eaux usées , Élimination des déchets liquides/méthodes , Nutriments/analyse , Nutriments/métabolisme , Céramiques , Membrane artificielle , Polluants chimiques de l'eau/analyse , Gravitation , Engrais
3.
Sensors (Basel) ; 23(24)2023 Dec 18.
Article de Anglais | MEDLINE | ID: mdl-38139733

RÉSUMÉ

Colorimetric sensors have attracted considerable attention in many sensing applications because of their specificity, high sensitivity, cost-effectiveness, ease of use, rapid analysis, simplicity of operation, and clear visibility to the naked eye [...].

4.
Sci Total Environ ; 905: 166881, 2023 Dec 20.
Article de Anglais | MEDLINE | ID: mdl-37678534

RÉSUMÉ

The greatest challenge for the agriculture sector in the twenty-first century is to increase agricultural production to feed the burgeoning global population while maintaining soil health and the integrity of the agroecosystem. Currently, the application of biochar is widely implemented as an effective means for boosting sustainable agriculture while having a negligible influence on ecosystems and the environment. In comparison to traditional biochar, nano-biochar (nano-BC) boasts enhanced specific surface area, adsorption capacity, and mobility properties within soil, allowing it to promote soil properties, crop growth, and environmental remediation. Additionally, carbon sequestration and reduction of methane and nitrous oxide emissions from agriculture can be achieved with nano-BC applications, contributing to climate change mitigation. Nonetheless, due to cost-effectiveness, sustainability, and environmental friendliness, waste-derived nano-BC may emerge as the most viable alternative to conventional waste management strategies, contributing to the circular bioeconomy and the broader goal of achieving the Sustainable Development Goals (SDGs). However, it's important to note that research on nano-BC is still in its nascent stages. Potential risks, including toxicity in aquatic and terrestrial environments, necessitate extensive field investigations. This review delineates the potential of waste-derived nano-BC for sustainable agriculture and environmental applications, outlining current advancements, challenges, and possibilities in the realms from a sustainability and circular bioeconomy standpoint.


Sujet(s)
Agriculture , Écosystème , Charbon de bois , Sol
5.
PeerJ ; 11: e15599, 2023.
Article de Anglais | MEDLINE | ID: mdl-37456864

RÉSUMÉ

As an important farmed fish, tilapia has poor tolerance to low-temperatures. At the same time, different tilapia strains have apparent differences in low-temperature tolerance. In this study, using the iTRAQ method, the phosphorylated proteomics of two tilapia strains (Oreochromis niloticus and Oreochromis aureus) with different tolerances to low-temperature stress were quantitatively and comparatively analyzed, to clarify the physiological mechanism of tilapia's response to low-temperature stress. Through the GO and IPR analyses of differentially phosphorylated proteins, a number of similarities in physiological activities and regulatory effects were found between the two tilapias in response to low-temperature stress. Many differentially phosphorylated proteins are mainly involved in lipid metabolism, cell proliferation and apoptosis. However, the difference in endurance of low temperature of these two tilapias might be related to the differences in categories, expression and modification level of genetic products which were involved in the aforementioned physiological processes. And meanwhile, the enrichment results of KEGG showed the changes of multiple immune-related and growth-related phosphorylated proteins in the cytokine-cytokine receptor interaction pathway in O. aureus are more prominent. Furthermore, the significantly enriched pathway of carbohydrate digestion and absorption in O. niloticus may indicate that low-temperature stress exerts a more severe impact on energy metabolism. The relative results would help elucidating the molecular mechanism by which tilapia responds to low-temperature stress, and developing culture of tilapia species.


Sujet(s)
Cichlides , Tilapia , Animaux , Tilapia/génétique , Cichlides/génétique , Température , Basse température , Cytokines/métabolisme
6.
J Hazard Mater ; 442: 130089, 2023 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-36303344

RÉSUMÉ

Removal of radioactive uranyl ions (UO22+) from water by effective adsorbents is highly desired but remains a challenge. UO22+ are easily combined with H2O, and the polarization of H2O affects the complexation between UO22+ and the adsorbent. Thus, it is necessary to reconstruct the UO22+ active site to improve the adsorption capacity. Herein ,an amphiphilic ligand, namely N, N-dimethyl-9-decenamide (NND), is successfully prepared. NND replace H2O in [UO2(H2O)5]2+ by hydrogen bonding, thereby enhancing the adsorption capacity of MoS2 particles in the reconstituted UO22+ active sites. The predicted maximum adsorption capacity increased from 50.7 to 500.7 mg g- 1 (by a factor of 9.87) with the presence of NND, which is higher than other functional group-modified MoS2 adsorbents. Furthermore, NND and MoS2 can retain UO22+ uptake under extreme conditions including high acid-base and gamma irradiation. Theoretical Calculations of NND through H bonding produces an increased amount of charge transfer and a reduced adsorption energy between UO22+ and MoS2, which weakens the polarization effect of H2O. The findings showed that NND appeared to be a promising amphiphilic to improve the adsorption efficiency of UO22+ from water.

7.
Environ Pollut ; 307: 119524, 2022 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-35636716

RÉSUMÉ

Current synthesis routes of bismuth oxide nanosheets (BiONS) are relatively complicated, requiring the use of halogens or metalloids. Herein, a facile method to synthesize BiONS without the addition of halogens or other metalloids was developed. The synthesized BiONS were identified to have flake-shaped structures (300-1000 nm in width) with the thickness of 6-10 nm, which were predominantly made of ß-Bi2O3. Such BiONS were applied to modify the surface of screen-printed carbon electrodes (BiONS-SPCEs) for the development of a robust palladium (Pd2+) sensor. After optimizing the electrochemical parameters of the sensor, it was found that the linear sensor response range and limit of detection for Pd2+ were 40-400 and 1.4 ppb, respectively. The electrocatalytic activity of the Pd2+-sensor was validated in the competing environment of other metal and metalloid ions. Real samples collected during a Pd recovery process from pharmaceutical wastewater were used to verify the application of BiONS-SPCEs in control of palladium recovery process. The quantitative results of post recovery palladium concentrations obtained using BiONS-SPCEs in treated pharmaceutical wastewater samples were in good agreement with those obtained by inductively coupled plasma-optical emission spectrometry (ICP-OES). Thus, such Pd2+-sensor provided the possibility of on-site process control of complex industrial samples for obtaining near-instant information that would lead to better management of resources used in the process, and same time assure environmental standards for both recovered products and processed discharge.


Sujet(s)
Métalloïdes , Palladium , Bismuth/composition chimique , Techniques électrochimiques/méthodes , Électrodes , Halogènes , Palladium/composition chimique , Préparations pharmaceutiques , Eaux usées
8.
J Environ Manage ; 317: 115385, 2022 Sep 01.
Article de Anglais | MEDLINE | ID: mdl-35640404

RÉSUMÉ

This study comparatively investigated the influence of changes in pyrolysis temperature on the physicochemical, structural, and adsorptive properties of biochars derived from a green waste (Cynodon dactylon L.). For this purpose, the biophysically dried green wastes were pyrolyzed at 400 °C, 600 °C, and 800 °C under the same pyrolysis conditions. The results revealed that the physicochemical and structural properties were varied, depending upon the pyrolysis temperatures. With the increase of pyrolysis temperature, the surface functional groups were escaped, the structure became more porous (pore volume of 0.089 ± 0.001), the metal oxides were remained consistent, and the biochars turned into more alkaline nature (pH of 11.9 ± 0.2). Furthermore, as referring to the adsorptive performance for potentially toxic elements, with experimental adsorption capacity of up to 33.7 mg g-1 and removal rate up to 96% for a multi-metals containing solution, the biochars pyrolyzed at high temperature (800 °C) was significantly (p < 0.05) higher than those pyrolyzed at low temperature (400 °C). According to the physicochemical and structural properties, and the adsorptive performances of the biochars, the optimal pyrolysis temperature was herein recommended to be 800 °C.


Sujet(s)
Charbon de bois , Pyrolyse , Adsorption , Charbon de bois/composition chimique , Température
9.
J Hazard Mater ; 419: 126450, 2021 10 05.
Article de Anglais | MEDLINE | ID: mdl-34323708

RÉSUMÉ

In this study, industrial wastewater and groundwater were comparatively investigated for their physicochemical properties, concentrations of potentially toxic elements (PTEs), human health risks and pollution source(s). Every month, 34 wastewater samples and 26 groundwater samples were collected, for a duration of one year. The results showed that the physicochemical parameters and concentrations of PTEs in the industrial wastewater exceeded the maximum permissible limits of Pakistan Environmental Protection Agency (2000). Specifically, it was found that total dissolved solids (5%), total suspended solids (190%), chemical oxygen demand (107%), five-days biochemical oxygen demand (5.7 times), grease/oil (27.1 times), Fe (67%), Zn (29%), Mn (32%), Cu (27%), Ni (16%), Cr (8%), Pb (106%), and Cd (80%) were higher than the permissible limits. The carcinogenic and non-carcinogenic dermal health risks for wastewater irrigation group were significantly higher than the groundwater irrigation group. The hazard index of irrigation with industrial wastewater was 180 times higher than the groundwater. The principal component analysis indicated that industry was the main polluting source. The cluster analysis results of all PTEs (except Fe) were found in the same clade in the dendrogram, which showed a strong similarity within the monthly data set of the whole year. The study recommends using adjacent groundwater instead of industrial wastewater for irrigation purposes.


Sujet(s)
Métaux lourds , Eaux usées , Surveillance de l'environnement , Humains , Métaux lourds/analyse , Pakistan , Appréciation des risques
10.
Chemosphere ; 281: 130880, 2021 Oct.
Article de Anglais | MEDLINE | ID: mdl-34029966

RÉSUMÉ

The oxidation state of ions is a crucial aspect that often has been overlooked when determining the toxicity of chromium (Cr) species in environmental samples. In this study, a novel electrochemical sensor array based on gold-silver nanoparticles modified electrodes was developed for simultaneous determination of the two main chromium species (Cr(III) and (VI)). Specifically, the working electrodes of screen-printed carbon electrodes (SPCEs) were modified with silver-gold bimetallic nanoparticles through electrochemical deposition for detection of Cr(VI). The silver-gold bimetallic nanoparticles were further oxidized to form stable silver-gold bimetallic oxide nanoparticles for the detection of Cr(III). The results showed that the addition of silver with a theoretical value of 1% of gold could contribute to the formation and stabilization of oxides on the surface of gold nanoparticles. After characterization, the two kinds of electrodes were integrated as an electrochemical sensor array for selective and sensitive detection of Cr(VI) and Cr(III). The linear range and limit of detection (LOD, identified by three times of signal-to-noise ratio) were found to be 0.05-5 ppm and 0.1 ppb for Cr(VI), and 0.05-1 ppm and 0.1 ppb for Cr(III), respectively. Finally, the electrochemical sensor array was proven for successful detection of Cr(VI) and Cr(III) in tap water, artificial saliva and artificial sweat samples, and monitoring of Cr(VI) and Cr(III) in chromium-containing wastewater treatment process. Combined with a handheld dual-channel electrochemical device, the simultaneous determination of Cr(VI), Cr(III) and total chromium contents can be easily achieved for various samples.


Sujet(s)
Or , Nanoparticules métalliques , Chrome/analyse , Argent , Eaux usées
11.
Chemosphere ; 278: 130462, 2021 Sep.
Article de Anglais | MEDLINE | ID: mdl-33845436

RÉSUMÉ

Voltammetric sensors based on screen-printed electrodes (SPEs) await diverse applications in environmental monitoring, food, agricultural and biomedical analysis. However, due to the single-use and disposable characteristics of SPEs and the scale of measurements performed, their environmental impacts should be considered. A life cycle assessment was conducted to evaluate the environmental footprint of SPEs manufactured using various substrate materials (SMs: cotton textile, HDPE plastic, Kraft paper, graphic paper, glass, and ceramic) and electrode materials (EMs: platinum, gold, silver, copper, carbon black, and carbon nanotubes (CNTs)). The greatest environmental impact was observed when cotton textile was used as SM. HDPE plastic demonstrated the least impact (13 out of 19 categories), followed by ceramic, glass and paper. However, considering the end-of-life scenarios and release of microplastics into the environment, ceramic, glass or paper could be the most suitable options for SMs. Amongst the EMs, the replacement of metals, especially noble metals, by carbon-based EMs greatly reduces the environmental footprint of SPEs. Compared with other materials, carbon black was the least impactful on the environment. On the other hand, copper and waste-derived CNTs (WCNTs) showed low impacts except for terrestrial ecotoxicity and human toxicity (non-cancer) potentials. In comparison to commercial CNTs (CCNTs), WCNTs demonstrated lower environmental footprint and comparable voltammetric performance in heavy metal detections, justifying the substitution of CCNTs with WCNTs in commercial applications. In conclusion, a combination of carbon black or WCNTs EMs with ceramic, glass or paper SMs represents the most environmentally friendly SPE configurations for voltammetric sensor arrangement.


Sujet(s)
Nanotubes de carbone , Céramiques , Électrodes , Humains , Matières plastiques
12.
Anal Chim Acta ; 1162: 338304, 2021 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-33926699

RÉSUMÉ

The solid contact ion-selective electrodes (SC-ISEs) have been extensively studied in the field of ion sensing as they offer the possibility of miniaturization, are relatively inexpensive in comparison to other analytical techniques and allow straightforward and routine analyses of ions in a number of clinical, environmental and industrial process samples. In recent years, significant interest has grown in the development of SC-ISEs with well-defined interfacialpotentials at the membrane, solid contact, and substrate electrode interfaces. This has resulted in interesting SC-ISEs exhibiting high electrode-to-electrode potential reproducibility, for those made in a single batch of electrodes, some approaching or exceeding those observed in liquid-contact ISEs. The advancement in the potential reproducibility of SC-ISEs has been partially achieved by scrutinizing insufficiently reproducible fabrication methods of SC-ISEs, or by introducing novel control measures or modifiers to components of the ISEs. This paper provides an overview of the methods as well as the challenges in establishing and maintaining reproducible potentials during the fabrication and use of novel SC-ISEs. The rules outlined in the works reviewed may form the basis of further development of cost-effective, user-friendly, limited calibration or calibration-free potentiometric SC-ISEs to achieve reliable ion analyses here and now.

13.
Chemosphere ; 277: 130350, 2021 Aug.
Article de Anglais | MEDLINE | ID: mdl-33794433

RÉSUMÉ

The impact of different biochars (BCs) on the physicochemical properties and immobilization of potentially toxic elements (PTEs) in contaminated soil irrigated with industrial wastewater for the last three decades was studied. Furthermore, the efficacy of applied BCs in reducing geostatistical risks was also evaluated. For this purpose, BCs were prepared from green waste (Cynodon dactylon L.) for the first time at different pyrolysis temperature (400 °C, 600 °C and 800 °C), and amended the contaminated soil in pots with two different ratios of 2% and 5% (w/w) under controlled conditions. The BCs amended soil samples were analyzed after five months (equivalent to the life span of a wheat crop). The physicochemical impacts of applied BCs on the soil showed that the acidic soil was changed to basic. A tremendous increase in water holding capacity, cation exchange capacity, dissolved organic carbon, carbon, phosphorus and potassium contents was observed. The PTEs concentrations and geostatistical risks were significantly (p ≤ 0.05) decreased by all the BCs. Among them, BC prepared at 800 °C and applied at a ratio of 5% was showed the best effects by reducing the bioavailable concentrations of Cd, Pb, Cr, Ni, Cu, Mn, Fe, As, Co and Zn in 88%, 87%, 78%, 76%, 69%, 65%, 64%, 63%, 46% and 21%, respectively. Similarly, significant (p ≤ 0.05) reductions in geoaccumulation index, enrichment factor, contamination factor, and ecological risk were recorded. Therefore, BC prepared at 800 °C and applied at a ratio of 5% is recommended for soil remediation.


Sujet(s)
Métaux lourds , Polluants du sol , Charbon de bois , Métaux lourds/analyse , Sol , Polluants du sol/analyse
14.
Chemosphere ; 269: 128699, 2021 Apr.
Article de Anglais | MEDLINE | ID: mdl-33121813

RÉSUMÉ

Para-Cresol is a water-soluble organic pollutant, which is harmful to organisms even at low concentrations. Therefore, it is important to rapidly detect the p-cresol in wastewater as well as natural water. In this work, a new, simple and stable biosensor was developed for on-site quantitatively determination and near real-time monitoring p-cresol in wastewater. The new biosensor was designed and fabricated using a screen-printed carbon electrode (SPCE) modified by waste-derived carbon nanotubes (CNTs) immobilized with laccase (LAC). The fabrication processes and performance of the biosensors were systematically characterized and optimized by Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and electrochemical methods. With improved conductivity, the proposed biosensor could provide the direct quantitation of p-cresol. The linear range of the biosensor is 0.2-25 ppm of p-cresol with a detection limit of 0.05 ppm. Additionally, the biosensor exhibited high reproducibility, stability and reusability during the validation. More importantly, the biosensor was successfully applied for the rapid detection of p-cresol in environmental lab wastewater under the interference of metal ions and other organics, and the results were consistent with high-performance liquid chromatography (HPLC). Finally, the biosensor with a portable potentiostat was approved as an easy-to-use, sensitive and inexpensive platform that could provide near real-time monitoring of p-cresol concentration in wastewater during Fenton oxidation treatment process.


Sujet(s)
Techniques de biocapteur , Nanotubes de carbone , Crésols , Électrodes , Laccase , Reproductibilité des résultats , Eaux usées
15.
Chempluschem ; 2020 Aug 21.
Article de Anglais | MEDLINE | ID: mdl-32881384

RÉSUMÉ

The rise in human pandemics demands prudent approaches in antiviral material development for disease prevention and treatment via effective protective equipment and therapeutic strategy. However, the current state of the antiviral materials research is predominantly aligned towards drug development and its related areas, catering to the field of pharmaceutical technology. This review distinguishes the research advances in terms of innovative materials exhibiting antiviral activities that take advantage of fast-developing nanotechnology and biopolymer technology. Essential concepts of antiviral principles and underlying mechanisms are illustrated, followed with detailed descriptions of novel antiviral materials including inorganic nanomaterials, organic nanomaterials and biopolymers. The biomedical applications of the antiviral materials are also elaborated based on the specific categorization. Challenges and future prospects are discussed to facilitate the research and development of protective solutions and curative treatments.

16.
Nanoscale ; 12(24): 13028-13033, 2020 Jun 28.
Article de Anglais | MEDLINE | ID: mdl-32537620

RÉSUMÉ

Non-precious metal-nitrogen-carbon (MNC) materials have been recognized as alternatives to noble-metal catalysts, such as Au/C, Pt/C and Ru/C. As the precursors of MNC catalysts, carbonized zeolite imidazole frameworks (ZIFs) have been widely studied due to their porosity and the composition of ligands, including carbon and nitrogen. Herein, we successfully synthesize a non-precious metal-based ORR catalyst with nickel nanoparticles anchored on cobalt and nitrogen co-doped porous carbon/carbon nanotubes (Ni/Co-NC), employing ZIF-67 metal-organic frameworks as precursors. The Ni/Co-NC catalyst shows an excellent onset potential of 0.984 V and a half-wave potential of 0.869 V in 0.1 M KOH, comparable to those of commercial Pt/C. The excellent ORR performance of Ni/Co-NC was attributed to the synergistic coexistence of the atomically dispersed metal species coordinated with nitrogen (metal-N sites) and carbon-encapsulated nickel nanoparticles as well as the hierarchical porous structure in the catalyst. In addition, the Ni/Co-NC catalyst possesses outstanding anti-poisoning capacity and long-term duration against methanol crossover in an alkaline environment. The obtained results enable the Ni/Co-NC catalyst to explore potential applications in energy conversion and storage systems.

17.
Environ Pollut ; 260: 113887, 2020 May.
Article de Anglais | MEDLINE | ID: mdl-31982801

RÉSUMÉ

In the present study, biochars (BCs) derived from naturally grown green waste (Cynodon dactylon L.) were investigated regarding their impacts on bioaccumulation of potentially toxic elements (PTEs), agronomic properties and human health risks of wheat crop cultivated on long-term industrially contaminated soil. Typically, three types of BCs were pyrolyzed at different highest temperature of treatment (HTT), i.e. 400 °C, 600 °C and 800 °C, in a horizontal reactor and applied to the contaminated soil with 2% and 5% (w/w) ratio. The characterization results of the BCs showed that significant positive changes in fundamental characteristics such as porosity, surface area, cation exchange capacity, dissolved organic carbon, phosphorus and potassium have occurred with increased HTT. The analytical results of wheat crop indicated that the BCs applications significantly (p ≤ 0.05) reduced concentration of PTEs in roots (48-95%), shoots (38-91%), leaves (30-91%) and grains (38-93%) of wheat plants. After the BCs application, the agronomic properties were enhanced up to 6-18%, 18-38%, 17-46%, 13-45%, 15-42%, 22-55% and 34-57% for germination rate, shoot length, shoot biomass, spike length, spike biomass, grain biomass and root biomass respectively. The human health risks of PTEs were significantly (p ≤ 0.05) decreased (31-93%) from toxicity level to safe level (except for Mn and Cu), after the BCs application. Based on the current study, the BCs (especially 800BC5) were recommended for reducing bioaccumulation of PTEs in different parts of the wheat plant, increasing growth and yield of wheat crop and decreasing human health risks via consumption of wheat grains.


Sujet(s)
Charbon de bois , Polluants du sol , Triticum , Bioaccumulation , Biomasse , Charbon de bois/pharmacologie , Indicateurs d'état de santé , Humains , Sol/composition chimique , Polluants du sol/métabolisme , Polluants du sol/toxicité , Triticum/composition chimique , Triticum/métabolisme
18.
J Pharm Biomed Anal ; 179: 112913, 2020 Feb 05.
Article de Anglais | MEDLINE | ID: mdl-31679844

RÉSUMÉ

Phenolic compounds are bioactive natural products of considerable interest in pharmaceuticals and biomedicines. Due to their bioactive functions, phenolic compounds have received increasing attention in recent years. Therefore, it is necessary to develop new and advanced analytical methods for determination of phenolic compounds in relation to pharmaceutical and biomedical applications. However, in majority, their detection has been largely conducted by sensitive yet bulky and expensive laboratory instruments, such as gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. Compared with those laboratory scale instruments, the advanced sensing technologies are extremely attractive due to the advantages of their low cost, time saving, user-friendly, simplified sample pre-treatment, high sensitivity, and excellent selectivity. The aim of this review is to provide critical information on the advanced sensing technologies for detecting phenolic compounds, with emphasis on optical sensors, electrochemical sensors and biosensors. Besides, the present status, critical issues and future trends of the related sensing technologies are outlined.


Sujet(s)
Techniques de biocapteur , Techniques électrochimiques , Phénols/analyse , Techniques de chimie analytique/méthodes
19.
J Chromatogr A ; 1611: 460604, 2020 Jan 25.
Article de Anglais | MEDLINE | ID: mdl-31676090

RÉSUMÉ

From the analytical chemistry point-of-view, an ideal sample preparation method should be simple, rapid, automatic, selective, precise, exhaustive, reproducible and protect the analyte-of-interest from degradation. In this study, a novel sample preparation method, named pressurized matrix solid-phase dispersion (p-MSPD) extraction was developed for simultaneously extracting, separating, purifying, isolating, and analyzing endogenous components in a solid sample matrix. Etlingera elatior, a traditional medicinal plant known as the torch ginger, was applied as a sample matrix to evaluate the p-MSPD process. The entire extraction, separation, isolation, fractionation and detection were performed automatically with a commercial LC-MS system. The novel method was satisfactorily applied for the preparation of real samples without optimization, which had the ability to selectively isolate pure compounds from the solid sample matrix for further NMR analysis. Therefore, the method is recommended for quality control of traditional medicines, research efforts when sample amounts are limited, and laboratories that have ordinary LC-MS instrumentation.


Sujet(s)
Chromatographie en phase liquide/méthodes , Spectrométrie de masse/méthodes , Composés phytochimiques/isolement et purification , Extraction en phase solide/méthodes , Zingiberaceae/composition chimique , Automatisation , Spectroscopie par résonance magnétique du carbone-13 , Fractionnement chimique , Composés phytochimiques/composition chimique , Spectroscopie par résonance magnétique du proton
20.
J Environ Manage ; 232: 615-624, 2019 Feb 15.
Article de Anglais | MEDLINE | ID: mdl-30522068

RÉSUMÉ

With increasing demand for biodiesel, crude glycerol as a by-product in biodiesel production has been generated and oversupplied. This study, therefore, explored the pretreatment and a subsequent two-stage microbial system to convert crude glycerol into high value-added products: 1,3-propanediol (1,3-PDO) and polyhydroxyalkanoates (PHAs). After pretreatment, long chain fatty acids (LCFAs) could be effectively removed from crude glycerol to eliminate the inhibition effects on subsequent microbial process. In the anaerobic fermentation, when fed treated crude glycerol increased from 20 g/L to 100 g/L, 1,3-PDO yield decreased from 0.438 g/g to 0.345 g/g and accompanied carboxylic acids shifted from acetate and lactate dominant to lactate overwhelmingly dominant. Meanwhile, the relative abundance of Clostridiales sustained around 50% but Enterobacteriales increased from 19% to 53%. Further fed glycerol increase to 140 g/L resulted in severe substrate inhibition, which could be relieved by intermittent feeding. In aerobic process, glycerol anaerobic digestion effluent (ADE) was fed to the consortium of Bacillus megaterium and Corynebacterium hydrocarbooxydans for selectively consumption of carboxylic acids and residual glycerol from 1,3-PDO to produce PHAs as a secondary high value-added product. The consortium accumulated maximum 8.0 g/L poly (3-hydroxybutyrate) (PHB), and 1,3-PDO purity increased from initial 27.7% to almost 100% when fed with 100 g/L glycerol ADE. Overall, this study provided comprehensive and insightful information on microbial conversion of crude glycerol to high value-added products after pretreatment.


Sujet(s)
Glycérol , Polyhydroxyalcanoates , Fermentation , Propylène glycols
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