Bioreactors for Degradation of Toxic Pollutant in Wastewater System

Sensing Microcystin-LR (MC-LR) is an important issue for environmental monitoring, as the MC-LR is a common toxic pollutant found in freshwater bodies. The demand for sensitive detection method of MC-LR at low concentrations can be addressed by metasurface-based sensors, which are feasible and highly efficient. Here, we demonstrate an all-dielectric metasurface for sensing MC-LR. Its working principle is based on quasi-bound states in the continuum mode (QBIC), and it manifests a high-quality factor and high sensitivity. The dielectric metasurface can detect a small change in the refractive index of the surrounding environment with a quality factor of ~170 and a sensitivity of ~788 nm/RIU. MC-LR can be specifically identified in mixed water with a concentration limit of as low as 0.002 μg/L by a specific recognition technique for combined antigen and antibody. Furthermore, the demonstrated detection of MC-LR can be extended to the identification and monitoring of other analytes, such as viruses, and the designed dielectric metasurface can serve as a monitor platform with high sensitivity and high specific recognition capability.

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Chromium (VI) Uptake and Tolerance Potential in Cotton Cultivars: Effect on Their Root Physiology, Ultramorphology, and Oxidative Metabolism

BioMed Research International ◽

10.1155/2014/975946 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 25

Author(s):

M. K. Daud ◽

Lei Mei ◽

M. T. Variath ◽

Shafaqat Ali ◽

Cheng Li ◽

...

Keyword(s):

Transgenic Cotton ◽

Hybrid Line ◽

Dense Granules ◽

Ultrastructural Studies ◽

Chromium Vi ◽

Multiple Biomarkers ◽

Toxic Pollutant ◽

Different Levels ◽

Secondary Roots ◽

Cr Uptake

Chromium (Cr) is present in our environment as a toxic pollutant, which needs to be removed using phytoremediation technology. In present study, two transgenic cotton cultivars (J208, Z905) and their hybrid line (ZD14) were used to explore their Cr uptake and tolerance potential using multiple biomarkers approach. Four different levels of Cr (CK, 10, 50, and 100 μM) were applied. Cr caused a significant reduction in root/shoot length, number of secondary roots, and root fresh and dry biomasses at 100μM. Cr accumulated more in roots and was found higher in hybrid line (ZD14) as compared with its parent lines (J208, Z905) at all Cr stress levels (10, 50, and 100 μM). Cr translocation was less than 1 in all cultivars. Ultrastructural studies at 100 μM Cr showed an increase in number of nuclei and vacuoles and presence of Cr dense granules in dead parts of the cell (vacuoles/cell wall). Malondialdehyde (MDA), hydrogen peroxide (H2O2), total soluble proteins, superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT), and glutathione reductase (GR) as a whole were upregulated with elevated levels of Cr. Higher Cr uptake by roots, accelerated metabolism, and Cr sequestration in dead parts of the cell indicate that these cotton cultivars can be useful for Cr accumulation and tolerance.

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Maintenance Role of a Glutathionyl-Hydroquinone Lyase (PcpF) in Pentachlorophenol Degradation by Sphingobium chlorophenolicum ATCC 39723

Journal of Bacteriology ◽

10.1128/jb.00489-08 ◽

2008 ◽

Vol 190 (23) ◽

pp. 7595-7600 ◽

Cited By ~ 21

Author(s):

Yan Huang ◽

Randy Xun ◽

Guanjun Chen ◽

Luying Xun

Keyword(s):

Degradation Rate ◽

Tricarboxylic Acid Cycle ◽

Degradation Pathway ◽

Tricarboxylic Acid ◽

Metabolic Intermediate ◽

Reductive Dehalogenase ◽

Cell Extracts ◽

Toxic Pollutant ◽

Sphingobium Chlorophenolicum

ABSTRACT Pentachlorophenol (PCP) is a toxic pollutant. Its biodegradation has been extensively studied in Sphingobium chlorophenolicum ATCC 39723. All enzymes required to convert PCP to a common metabolic intermediate before entering the tricarboxylic acid cycle have been characterized. One of the enzymes is tetrachloro-p-hydroquinone (TeCH) reductive dehalogenase (PcpC), which is a glutathione (GSH) S-transferase (GST). PcpC catalyzes the GSH-dependent conversion of TeCH to trichloro-p-hydroquinone (TriCH) and then to dichloro-p-hydroquinone (DiCH) in the PCP degradation pathway. PcpC is susceptible to oxidative damage, and the damaged PcpC produces glutathionyl (GS) conjugates, GS-TriCH and GS-DiCH, which cannot be further metabolized by PcpC. The fate and effect of GS-hydroquinone conjugates were unknown. A putative GST gene (pcpF) is located next to pcpC on the bacterial chromosome. The pcpF gene was cloned, and the recombinant PcpF was purified. The purified PcpF was able to convert GS-TriCH and GS-DiCH conjugates to TriCH and DiCH, respectively. The GS-hydroquinone lyase reactions catalyzed by PcpF are rather unusual for a GST. The disruption of pcpF in S. chlorophenolicum made the mutant lose the GS-hydroquinone lyase activities in the cell extracts. The mutant became more sensitive to PCP toxicity and had a significantly decreased PCP degradation rate, likely due to the accumulation of the GS-hydroquinone conjugates inside the cell. Thus, PcpF played a maintenance role in PCP degradation and converted the GS-hydroquinone conjugates back to the intermediates of the PCP degradation pathway.

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The practical implementation of methanol as a clean and efficient alternative fuel for automotive vehicles

International Journal of Engine Research ◽

10.1177/1468087417752951 ◽

2018 ◽

Vol 20 (3) ◽

pp. 350-358 ◽

Cited By ~ 7

Author(s):

Harold Sun ◽

Wesley Wang ◽

Kim-Pui Koo

Keyword(s):

Alternative Fuels ◽

Gasoline Engine ◽

Low Cost ◽

Oxidation Catalyst ◽

Automotive Application ◽

Practical Implementation ◽

Emission Standard ◽

Gasoline Engines ◽

Toxic Pollutant ◽

Aldehyde Emission

Ever since the energy crises in 1970s, the methanol, among other alternative fuels, has been studied for automotive application. The methanol has been widely used for auto racing due to its superior anti-knock characteristics. However, aldehyde is a highly toxic pollutant and aldehyde emission out of alcohol fuel combustion could be considerably higher than spark-ignited gasoline engines. The corrosion and durability of methanol fuel components were also concerns for mass production of methanol-fueled vehicles. The authors have worked with an automotive manufacturer in China to investigate the brake thermal and emission improvement potentials of a methanol-fueled, spark-ignited engine over the original gasoline engine on a passenger car application and to demonstrate the performance and China V emission compliance over its useful life of 160,000 km. The study found that the methanol-fueled engine has 4%–6% brake thermal advantage over the original gasoline engine, and a three-way oxidation catalyst has successfully managed the tailpipe emissions under China V emission limit, consistently over the journey of 160,000 km. The test data show that the tailpipe aldehyde emission is actually reduced to a level that is below what is required by US LEV III emission standard, largely due to the three-way oxidation catalyst and the gasoline cold start assistance at the beginning of the transient emission cycle. This study indicates that methanol-fueled engine might be an attractive low-cost alternative for a more efficient and clean powertrain over conventional gasoline when a light-duty diesel engine faces challenges from future China VI emission regulations.

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Optimizing the Management of Cadmium Bioremediation Capacity of Metal-Resistant Pseudomonas sp. Strain Al-Dhabi-126 Isolated from the Industrial City of Saudi Arabian Environment

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16234788 ◽

2019 ◽

Vol 16 (23) ◽

pp. 4788 ◽

Cited By ~ 4

Author(s):

Naif Abdullah Al-Dhabi ◽

Galal Ali Esmail ◽

Abdul-Kareem Mohammed Ghilan ◽

Mariadhas Valan Arasu

Keyword(s):

Bacterial Strain ◽

Cadmium Toxicity ◽

Industrial Effluents ◽

Pseudomonas Sp ◽

Bacterial Strains ◽

16S Rdna Gene ◽

Sequence Characterization ◽

Industrial City ◽

Toxic Pollutant ◽

Cd Removal

In this study, 23 bacterial strains were isolated from a Cadmium (Cd) contaminated soil in the industrial city, Riyadh of Saudi Arabia. Among these isolates six strains were found to withstand cadmium contamination and grow well. From the six isolates Pseudomonas sp. strain Al-Dhabi-122–127 were found to resist cadmium toxicity to a higher level. The isolates were subjected to biochemical and 16S rDNA gene sequence characterization to confirm their identification. The bacterial strain Al-Dhabi-124 showed 1.5 times higher Cd-degrading activity than Al-Dhabi-122 and Al-Dhabi-123, and Al-Dhabi-126 exhibited 3.5 times higher Cd-degrading activity, higher than the other strains. An atomic absorption spectrophotometer study showed that the strain Al-Dhabi-126 absorbed Cd, and that the bacterial strain Al-Dhabi-126 was found to tolerate cadmium level up to 2100 µg/mL. The bacterial strain Al-Dhabi-126 showed a maximum Cd removal efficacy at pH between 6.0 and 8.0. The efficacy decreased sharply after an increase in pH (9.0). An optimum temperature of 50 °C and pH 6.0 were found to be effective for the Cd removal process by the isolate. The study indicated that the bacterial strain Al-Dhabi-126 can be used effectively for the bioremediation of heavy metals like cadmium, a major toxic pollutant in industrial effluents.

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The Toxic Effects of Sulfoxaflor Induced in Earthworms (Eisenia fetida) under Effective Concentrations

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17051740 ◽

2020 ◽

Vol 17 (5) ◽

pp. 1740

Author(s):

Xiaolian Zhang ◽

Xiuguo Wang ◽

Yalei Liu ◽

Kuan Fang ◽

Tong Liu

Keyword(s):

Insect Pests ◽

Thiobarbituric Acid ◽

Control Group ◽

Soil Invertebrate ◽

Glutathione S Transferase ◽

Neonicotinoid Insecticide ◽

Toxic Pollutant ◽

Sap Feeding ◽

High Concentrations ◽

Oh Content

Sulfoxaflor is a new kind of neonicotinoid insecticide that is used to control sap-feeding insect pests. In this study, a hazard assessment of sulfoxaflor on soil invertebrate earthworms was performed under effective concentrations. The results showed that different exposure times and doses had significant influence on the toxicity of sulfoxaflor. Sulfoxaflor degraded quickly in artificial soil with a degradation rate of 0.002–0.017 mg/(kg·d) and a half-life of 12.0–15.4 d. At 0.5 mg/kg and 1.0 mg/kg, the ·OH− content, antioxidant enzyme activeities, thiobarbituric acid reactive substances (TBARS) content and 8-OHdG content had significant differences compared to those in the control group. On the 56th day, significant differences were only observed in the Glutathione S-transferase enzyme (GST) activity and 8-OHdG content at 1.0 mg/kg compared to those in the control group due to the degradation of sulfoxaflor. This indicated that the risk of sulfoxaflor to earthworms was reduced because it was easily degraded in soil. However, because sulfoxaflor is a super toxic pollutant to earthworms, high concentrations of sulfoxaflor should not be released into the soil environment.

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Identification of Arsenic in the Water Using Energy Dispersive X-Ray Diffraction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.588-589.1108 ◽

2012 ◽

Vol 588-589 ◽

pp. 1108-1110

Author(s):

Fang Zhang ◽

Min Qiang Li ◽

Jin Huai Liu

Keyword(s):

Aqueous System ◽

Energy Dispersive ◽

X Ray Diffraction ◽

Sodium Arsenate ◽

Reservoir Water ◽

X Ray ◽

Low Concentrations ◽

Toxic Pollutant ◽

Significant Attention

The occurrence of arsenic in natural water has received signiﬁcant attention during recent years. The arsenic plays an important role for its behavior and toxicity in the aqueous system. Arsenic is a toxic pollutant in water with serious health effects upon long-term intake of even low concentrations through drinking water consumption population. By means of the energy-dispersive X-ray diffraction (EDXRD) technique, confected different concentrations of sodium arsenate solution and reservoir water of Tuoketuo county in the Inner Mongolia, were analyzed. The result shows that arsenic is present within reservoir water of Tuoketuo county. But, fluorescence peak photons of arsenic in the solution are not in proportion to the concentration. So, it is difficulty to quantitatively decide the concentration of the arsenic in the water.

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Air Quality Effects of Pollutant Gases from Brick Kilns near Chennai

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b3863.098319 ◽

2019 ◽

Vol 8 (3) ◽

pp. 2284-2291

Keyword(s):

Air Quality ◽

Air Pollutants ◽

Historical Data ◽

Oxides Of Nitrogen ◽

Brick Kiln ◽

Pollution Effects ◽

Brick Kilns ◽

Toxic Pollutant ◽

Carbon Dioxide Co2 ◽

Pollutant Gases

Brick kiln industries are commonly found in most of the regions in our country. Many private sectors consider this type of industry more as a business rather than giving importance to hygiene and health aspects. This work has focused on the air pollutants emitted from brick kiln industries near Chennai and its environmental effects. Majority of pollutants emitted were found to be oxides of nitrogen (NOx ), carbon dioxide (CO2 ) and oxides of sulphur (SOx ). Generally all these gases have adverse bad effects on the well health of human community. Workers in brick kiln industries are directly inhaling toxic pollutant gases and suffer with various health complexities. Sampling sites were chosen based on last five years historical data. Experimental survey was done in the chosen sampling sites to observe the severity of pollution around the place. Time bound study and observation was conducted to know the pollution effects in various months ranging from October 2018 to February 2019. Air Quality Index (AQI) was calculated and remedial measures were suggested.

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Acute toxicity test of carbamate insecticide on common carp, Cyprinus carpio Linnaeus, 1758

Jurnal Iktiologi Indonesia ◽

10.32491/jii.v18i3.340 ◽

2019 ◽

Vol 18 (3) ◽

pp. 191

Author(s):

Cathrine Ferlianova Leuwol ◽

Djamar Tumpal Floranthus Lumban Batu ◽

Ridwan Affandi

Keyword(s):

Acute Toxicity ◽

Cyprinus Carpio ◽

Toxicity Test ◽

Test Organism ◽

Preliminary Test ◽

Probit Analysis ◽

Acute Toxicity Test ◽

Common Carp Cyprinus Carpio ◽

Carbamate Insecticide ◽

Toxic Pollutant

Carbamate is a highly toxic pollutant for animal, even though this insecticide is biodegradable in nature and in the food chain. The purpose of this research was to find the LC50-96 of carbamate insecticide (Marshall 200 EC) on test organism. The test organism used common carps (Cyprinus carpio L.) with 6-8 cm of length and 5,5-9 g of weight. This study used an experimental method by divided into two steps i.e. preliminary test and acute toxicity (LC50-96) tests. Preliminary test was done without repetition and twice repetition for acute toxicity. Acute toxicity test data were analyzed by probit analysis. The result showed that LC50-96of carbamate insecticide (Marshal 200 EC) on Cyprinus carpio L. was 1,68 mgL-1.AbstrakPestisida golongan karbamat merupakan sumber pencemar yang sangat toksik bagi hewan, meskipun insektisida go-longan karbamat ini mudah terurai di alam baik pada media air maupun pada organisme dalam rantai makanan. Tujuan penelitian ini ialah mengukur nilai LC50-96 insektisida karbamat (Marshal 200 EC) terhadap hewan uji. Hewan uji yang digunakan pada penelitian ini adalah ikan mas (Cyprinus carpio L.) dengan panjang 6-8 cm dan bobot 5,5-9 g. Metode yang digunakan pada penelitian ini ialah metode eksperimental dengan dua tahapan penelitian, yaitu uji pendahuluan dan uji toksisitas akut (LC50-96). Uji pendahuluan dilakukan tanpa ulangan dan uji toksisitas akut dilakukan ulangan sebanyak dua kali. Data uji toksisitas akut dianalisis dengan analisis probit. Hasil penelitian menunjukkan bahwa nilai LC50-96 insektisida karbamat (Marshal 200 EC) terhadap ikan mas adalah 1,68 mgL-1.

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