Search results for: gas chromatography-mass spectrometry (GC-MS)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 613

Search results for: gas chromatography-mass spectrometry (GC-MS)

373 Surface-Enhanced Raman Detection in Chip-Based Chromatography via a Droplet Interface

Authors: Renata Gerhardt, Detlev Belder

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Raman spectroscopy has attracted much attention as a structurally descriptive and label-free detection method. It is particularly suited for chemical analysis given as it is non-destructive and molecules can be identified via the fingerprint region of the spectra. In this work possibilities are investigated how to integrate Raman spectroscopy as a detection method for chip-based chromatography, making use of a droplet interface. A demanding task in lab-on-a-chip applications is the specific and sensitive detection of low concentrated analytes in small volumes. Fluorescence detection is frequently utilized but restricted to fluorescent molecules. Furthermore, no structural information is provided. Another often applied technique is mass spectrometry which enables the identification of molecules based on their mass to charge ratio. Additionally, the obtained fragmentation pattern gives insight into the chemical structure. However, it is only applicable as an end-of-the-line detection because analytes are destroyed during measurements. In contrast to mass spectrometry, Raman spectroscopy can be applied on-chip and substances can be processed further downstream after detection. A major drawback of Raman spectroscopy is the inherent weakness of the Raman signal, which is due to the small cross-sections associated with the scattering process. Enhancement techniques, such as surface enhanced Raman spectroscopy (SERS), are employed to overcome the poor sensitivity even allowing detection on a single molecule level. In SERS measurements, Raman signal intensity is improved by several orders of magnitude if the analyte is in close proximity to nanostructured metal surfaces or nanoparticles. The main gain of lab-on-a-chip technology is the building block-like ability to seamlessly integrate different functionalities, such as synthesis, separation, derivatization and detection on a single device. We intend to utilize this powerful toolbox to realize Raman detection in chip-based chromatography. By interfacing on-chip separations with a droplet generator, the separated analytes are encapsulated into numerous discrete containers. These droplets can then be injected with a silver nanoparticle solution and investigated via Raman spectroscopy. Droplet microfluidics is a sub-discipline of microfluidics which instead of a continuous flow operates with the segmented flow. Segmented flow is created by merging two immiscible phases (usually an aqueous phase and oil) thus forming small discrete volumes of one phase in the carrier phase. The study surveys different chip designs to realize coupling of chip-based chromatography with droplet microfluidics. With regards to maintaining a sufficient flow rate for chromatographic separation and ensuring stable eluent flow over the column different flow rates of eluent and oil phase are tested. Furthermore, the detection of analytes in droplets with surface enhanced Raman spectroscopy is examined. The compartmentalization of separated compounds preserves the analytical resolution since the continuous phase restricts dispersion between the droplets. The droplets are ideal vessels for the insertion of silver colloids thus making use of the surface enhancement effect and improving the sensitivity of the detection. The long-term goal of this work is the first realization of coupling chip based chromatography with droplets microfluidics to employ surface enhanced Raman spectroscopy as means of detection.

Keywords: chip-based separation, chip LC, droplets, Raman spectroscopy, SERS

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372 Gold Nanoparticle: Synthesis, Characterization, Clinico-Pathological, Pathological and Bio-Distribution Studies in Rabbits

Authors: M. M. Bashandy, A. R. Ahmed, M. El-Gaffary, Sahar S. Abd El-Rahman

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This study evaluated the acute toxicity and tissue distribution of intravenously administered gold nanoparticles (AuNPs) in male rabbits. Rabbits were exposed to single dose of AuNPs (300 µg/ kg). Toxic effects were assessed via general behavior, hematological parameters, serum biochemical parameters and histopathological examination of various rabbits’ organs. Tissue distribution of AuNPs was evaluated at a dose of 300 µg/ kg in male rabbit. Inductively coupled plasma–mass spectrometry (ICP-MS) was used to determine gold concentrations in tissue samples collected at predetermined time intervals. After one week, AuNPs exerted no obvious acute toxicity in rabbits. However, inflammatory reactions in lung and liver cells were induced in rabbits treated at the300 µg/ kg dose level. The highest gold levels were found in the spleen, followed by liver, lungs and kidneys. These results indicated that AuNPs could be distributed extensively to various tissues in the body, but primarily in the spleen and liver.

Keywords: gold nanoparticles, toxicity, pathology, hematology, liver function, kidney function

Procedia PDF Downloads 306
371 Biomarkers for Rectal Adenocarcinoma Identified by Lipidomic and Bioinformatic

Authors: Patricia O. Carvalho, Marcia C. F. Messias, Laura Credidio, Carlos A. R. Martinez

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Lipidomic strategy can provide important information regarding cancer pathogenesis mechanisms and could reveal new biomarkers to enable early diagnosis of rectal adenocarcinoma (RAC). This study set out to evaluate lipoperoxidation biomarkers, and lipidomic signature by gas chromatography (GC) and electrospray ionization-qToF-mass spectrometry (ESI-qToF-MS) combined with multivariate data analysis in plasma from 23 RAC patients (early- or advanced-stages cancer) and 18 healthy controls. The most abundant ions identified in the RAC patients were those of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) while those of lisophosphatidylcholine (LPC), identified as LPC (16:1), LPC (18:1) and LPC (18:2), were down-regulated. LPC plasmalogen containing palmitoleic acid (LPC (P-16:1)), with highest VIP score, showed a low tendency in the cancer patients. Malondialdehyde plasma levels were higher in patients with advanced cancer (III/IV stages) than in the early stages groups and the healthy group (p<0.05). No differences in F2-isoprostane levels were observed between these groups. This study shows that the reduction in plasma levels of LPC plasmalogens associated to an increase in MDA levels may indicate increased oxidative stress in these patients and identify the metabolite LPC (P-16:1) as new biomarkers for RAC.

Keywords: biomarkers, lipidomic, plasmalogen, rectal adenocarcinoma

Procedia PDF Downloads 198
370 Study of Ambient Air Quality on Building's Roof of Dhaka City

Authors: Koninika Tanzim

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The gaseous pollutants, SO2, NO2, CO and O3 affect the environment of Dhaka City. These pollutants are mainly released from stationary sources, like, fossil-fueled, power plants, industrial units and brickfields around the city. Suspended particulate matters including PM10 and PM2.5 are also contributing to air pollution in Dhaka City. SO2, NO2 and O3 are determined by using UV and visible spectrophotometry. The sensor type devised has been used for the determination of CO in ambient air. Lead in the suspended particulate matter was determined by using atomic absorption spectrometry. The samples were collected at ground level and on the roof of a seven-storied building. For all the criteria pollutants, the concentration at the roof was found to the lower than that at the ground level. The average concentration of PM10 and PM2.5 were found to the 241.5 and 81.1 mg/m3 at the ground level. On the roof of a 7 storied building was however 49.99 mg/m3 and 25.88 mg/m3 for PM10 and PM2.5 respectively. The concentration of Pb varied from 0.011 to 0.04 mg/m3 at the ground level. The values for Pb at the roof level were significantly lower. The values for SO2, NO2, CO and O3 were found to be higher than the USEPA values.

Keywords: gaseous air pollutant, PM, lead, gravimetry, spectrophotometry, atomic absorption, ambient air quality

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369 Adsorption of Methylene Blue by Pectin from Durian (Durio zibethinus) Seeds

Authors: Siti Nurkhalimah, Devita Wijiyanti, Kuntari

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Methylene blue is a popular water-soluble dye that is used for dyeing a variety of substrates such as bacteria, wool, and silk. Methylene blue discharged into the aquatic environment will cause health problems for living things. Treatment method for industrial wastewater may be divided into three main categories: physical, chemical, and biological. Among them, adsorption technology is generally considered to be an effective method for quickly lowering the concentration of dissolved dyes in a wastewater. This has attracted considerable research into low-cost alternative adsorbents for adsorbing or removing coloring matter. In this research, pectin from durian seeds was utilized here to assess their ability for the removal of methylene blue. Adsorption parameters are contact time and dye concentration were examined in the batch adsorption processes. Pectin characterization was performed by FTIR spectrometry. Methylene blue concentration was determined by using UV-Vis spectrophotometer. FTIR results show that the samples showed the typical fingerprint in IR spectrogram. The adsorption result on 10 mL of 5 mg/L methylene blue solution achieved 95.12% when contact time 10 minutes and pectin 0.2 g.

Keywords: pectin, methylene blue, adsorption, durian seed

Procedia PDF Downloads 152
368 NiO-CeO2 Nano-Catalyst for the Removal of Priority Organic Pollutants from Wastewater through Catalytic Wet Air Oxidation at Mild Conditions

Authors: Anushree, Chhaya Sharma, Satish Kumar

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Catalytic wet air oxidation (CWAO) is normally carried out at elevated temperature and pressure. This work investigates the potential of NiO-CeO2 nano-catalyst in CWAO of paper industry wastewater under milder operating conditions of 90 °C and 1 atm. The NiO-CeO2 nano-catalysts were synthesized by a simple co-precipitation method and characterized by X-ray diffraction (XRD), before and after use, in order to study any crystallographic change during experiment. The extent of metal-leaching from the catalyst was determined using the inductively coupled plasma optical emission spectrometry (ICP-OES). The catalytic activity of nano-catalysts was studied in terms of total organic carbon (TOC), adsorbable organic halides (AOX) and chlorophenolics (CHPs) removal. Interestingly, mixed oxide catalysts exhibited higher activity than the corresponding single-metal oxides. The maximum removal efficiency was achieved with Ce40Ni60 catalyst. The results indicate that the CWAO process is efficient in removing the priority organic pollutants from wastewater, as it exhibited up to 59% TOC, 55% AOX, and 54 % CHPs removal.

Keywords: catalysis, nano-materials, NiO-CeO2, paper mill, wastewater, wet air oxidation

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367 Assessment of Heavy Metal Contamination in Ground Water in the Coastal Part of Cauvery Deltaic Region, South India

Authors: Gnanachandrasamy G., Zhou Y., Ramkumar T., Venkatramanan S., Wang S., Mo Liping, Jingru Zhang

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In order to assess the heavy metal contamination totally fourty five groundwater samples were collected from the coastal part of Cauvery deltaic region, South India, during monsoon season in the year of 2017. The study area lies between longitudes 79º15’ to 79º 50’ E and latitudes 10º10’ to 11º20’ N with total area of 2,569 km². The concentration of As, Ba, Cd, Cr, Co, Cu, Ni, Pb, Se, and Zn were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The heavy metals ranged between 0.007-117.8 µg/l for As, 8.503-1281 µg/l for Ba, 0.006-0.12 µg/l for Cd, 0.23-5.572µg/l for Cr, 0.44-17.9 µg/l for Co, 0.633-11.56 µg/l for Cu, 0.467-29.34 µg/l for Ni, 0.008-5.756 µg/l for Pb, 0.979 to 45.49 µg/l for Se, and 2.712-10480 µg/l for Zn in the groundwaters. A comparison of heavy metal concentration with WHO and BIS drinking water standards shows that Ni, Zn, As, Se, and Ba level is higher than the drinking water standards in some of the groundwater samples, and the concentrations of all the other heavy metals were lower than the drinking water standards. The present levels of heavy metal concentration in the studied area groundwaters are moderate to severe to public health and environmental concerns and need attention.

Keywords: cauvery delta, drinking water, groundwater, heavy metals

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366 Waste Egg Albumin Derived Small Peptides Stimulate Photosynthetic Electron Transport

Authors: Seungwon Han, Sung young Yoo, Tae Wan Kim

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The objective of this study was to measure the changes in the photochemical response in the leaves of red pepper (Capsium annuum L.) after foliar fertilization of amino acid and small peptides derived from the waste egg. As a nitrogen fertilizer, waste eggs were incubated over one 1week and then degraded as amino acids and small peptides. The smaller peptides less than 20 kDa were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS). MALDI-TOF-MS as a rapid analysis method was to show the molecular mass of degraded egg protein. The sequences of peptides were identified as follows; γ-Glu- Cys-γ-Glu-Cys-γ-Glu-Cys)-Ser and γ-Glu-Cys-γ-Glu-Cys-γ-Glu- Cys)-Gly. It was clearly illuminated that the parameters related to quantum yields for PSI electron transport (ΦRE1O, ΨRE1O, δRE1O) and RC/ABS have increased tendency by small peptide application. On the other hand, phenomenological energy fluxes (ABSO/CSM, TRO/CSM, ET2O/CSM, RE1O/CSM, DIO/CSM) have considerably fluctuated with foliar fertilization of small peptides. In conclusion, the small peptides can enhance the photochemical activities from photosystem II to photosystem I. This study was financially supported by RDA Agenda Project PJ 016196012022.

Keywords: electron transport, foliar fertilization, small peptide, waste egg

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365 Comparison of the Hydration Products of Commercial and Experimental Calcium Silicate Cement: The Preliminary Observational Study

Authors: Seok Woo Chang

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Aim: The objective of this study was to compare and evaluate the hydration products of commercial and experimental calcium silicate cement. Materials and Methods: The commercial calcium silicate cement (ProRoot MTA, Dentsply) and experimental calcium silicate cement (n=10) were mixed with distilled water (water/powder ratio = 20 w/w) and stirred at room temperature for 10 hours. These mixtures were dispersed on wafer and dried for 12 hours at room temperature. Thereafter, the dried specimens were examined with Scanning Electron Microscope (SEM). Electron Dispersive Spectrometry (EDS) was also carried out. Results: The commercial calcium silicate cement (ProRoot MTA) and experimental calcium silicate cement both showed precipitation of rod-like and globule-like crystals. Based on EDS analysis, these precipitates were supposed to be calcium hydroxide or calcium silicate hydrates. The degree of formation of these precipitates was higher in commercial MTA. Conclusions: Based on the results, both commercial and experimental calcium silicate cement had ability to produce calcium hydroxide or calcium silicate hydrate precipitates.

Keywords: calcium silicate cement, ProRoot MTA, precipitation, calcium hydroxide, calcium silicate hydrate

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364 Investigations of Inclusion Complexes of Imazapyr with 2-Hydroxypropyl(β/γ) Cyclodextrin Experimental and Molecular Modeling Approach

Authors: Abdalla A. Elbashir, Maali Saad Mokhtar, FakhrEldin O. Suliman

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The inclusion complexes of imazapyr (IMA) with 2-hydroxypropyl(β/γ) cyclodextrins (HP β/γ-CD), have been studied in aqueous media and in the solid state. In this work, fluorescence spectroscopy, electrospray-ionization mass spectrometry (ESI-MS), and HNMR were used to investigate and characterize the inclusion complexes of IMA with the cyclodextrins in solutions. The solid-state complexes were obtained by freeze-drying and were characterized by Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (PXRD). The most predominant complexes of IMA with both hosts are the 1:1 guest: host complexes. The association constants of IMA-HP β-CD and IMA-HP γ -CD were 115 and 215 L mol⁻¹, respectively. Molecular dynamic (MD) simulations were used to monitor the mode of inclusion and also to investigate the stability of these complexes in aqueous media at atomistic levels. The results obtained have indicated that these inclusion complexes are highly stable in aqueous media, thereby corroborating the experimental results. Additionally, it has been demonstrated that in addition to hydrophobic interactions and van der Waals interactions the presence of hydrogen bonding interactions of the type H---O and CH---O between the guest and the host have enhanced the stability of these complexes remarkably.

Keywords: imazapyr, inclusion complex, herbicides, 2-hydroxypropyl-β/γ-cyclodextrin

Procedia PDF Downloads 142
363 Accumulation of Phlorotannins in Abalone Haliotis discus Hannai after Feeding with Eisenia bicyclis

Authors: Bangoura Issa, Ji-Young Kang, M. T. H. Chowdhury, Ji-Eun Lee, Yong-Ki Hong

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Investigation was carried out for the production of value-added abalone Haliotis discus hannai containing bioactive phlorotannin by feeding phlorotannin-rich seaweed Eisenia bicyclis 2 weeks prior to harvesting. Accumulation of phlorotannins was proceded by feeding with E. bicyclis after 4 days of starvation. HPLC purification afforded two major phlorotannins. Mass spectrometry and 1H-nuclear magnetic resonance analysis clarified their structures to be as 7-phloroeckol and eckol. Throughout the feeding period of 20 days, 7-phloroeckolol was accumulated in the muscle (foot muscle tissue) up to 0.18±0.12 mg g-1 dry weight of tissue after 12 days. Eckol reached 0.21±0.03 mg g-1 dry weight of tissue after 18 days. By feeding Laminaria japonica as reference, abalone showed no detection of phlorotannins in the muscle tissue. Seaweed consumption and growth rate of abalone revealed almost similar when feed with E. bicyclis or L. japonicain 20 days. Phlorotannins reduction to half-maximal accumulation values took 1.0 day and 2.7 days for 7-phloroeckol and eckol respectively, after replacing the feed to L. japonica.

Keywords: abalone, accumulation, eisenia bicyclis, phlorotannins

Procedia PDF Downloads 356
362 Phosphoproteomic Analysis of the Response of Rice Leaves to Chitosan under Drought Stress

Authors: Narumon Phaonakrop, Janthima Jaresitthikunchai, Sittiruk Roytrakul, Wasinee Pongprayoon

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Chitosan has been proposed as a natural polymer, and it is derived from chitin. The objective of this research was to determine the growth promoting responses induced by chitosan at the molecular physiology level in Khao Dawk Mali 105 (KDML 105) rice (Oryza sativa L.) seedlings under drought stress by adding of 2% polyethylene glycol 4000 (PEG4000) to the nutrient solution and after removal of the drought stress (re-water). Oligomeric chitosan at 40 ppm could enhance shoot fresh weight and shoot dry weight during drought stress and re-water. After 7 days of drought stress and re-water, significant increases in chlorophyll a and chlorophyll b contents in KDML 105 cultivar were observed. The 749 phosphoproteins in rice leaf treated with chitosan could be resolved by phosphoprotein enrichment, tryptic digestion and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. They can be classified into 10 groups. Proteins involved in the metabolic process and biological regulation were upregulated in response to chitosan during drought stress. This work will help us to understand protein phosphorylation relating to chitosan response during drought stress in aromatic rice seedlings.

Keywords: Chitosan, drought, phosphoproteome, rice

Procedia PDF Downloads 122
361 Optimization of Ultrasound-Assisted Extraction and Microwave-Assisted Acid Digestion for the Determination of Heavy Metals in Tea Samples

Authors: Abu Harera Nadeem, Kingsley Donkor

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Tea is a popular beverage due to its flavour, aroma and antioxidant properties—with the most consumed varieties being green and black tea. Antioxidants in tea can lower the risk of Alzheimer’s and heart disease and obesity. However, these teas contain heavy metals such as Hg, Cd, or Pb, which can cause autoimmune diseases like Graves disease. In this study, 11 heavy metals in various commercial green, black, and oolong tea samples were determined using inductively coupled plasma-mass spectrometry (ICP-MS). Two methods of sample preparation were compared for accuracy and precision, which were microwave-assisted digestion and ultrasonic-assisted extraction. The developed method was further validated by detection limit, precision, and accuracy. Results showed that the proposed method was highly sensitive with detection limits within parts-per-billion levels. Reasonable method accuracy was obtained by spiked experiments. The findings of this study can be used to delve into the link between tea consumption and disease and to provide information for future studies on metal determination in tea.

Keywords: ICP-MS, green tea, black tea, microwave-assisted acid digestion, ultrasound-assisted extraction

Procedia PDF Downloads 88
360 Delicate Balance between Cardiac Stress and Protection: Role of Mitochondrial Proteins

Authors: Zuzana Tatarkova, Ivana Pilchova, Michal Cibulka, Martin Kolisek, Peter Racay, Peter Kaplan

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Introduction: Normal functioning of mitochondria is crucial for cardiac performance. Mitochondria undergo mitophagy and biogenesis, and mitochondrial proteins are subject to extensive post-translational modifications. The state of mitochondrial homeostasis reflects overall cellular fitness and longevity. Perturbed mitochondria produce less ATP, release greater amounts of reactive molecules, and are more prone to apoptosis. Therefore mitochondrial turnover is an integral aspect of quality control in which dysfunctional mitochondria are selectively eliminated through mitophagy. Currently, the progressive deterioration of physiological functions is seen as accumulation of modified/damaged proteins with limiting regenerative ability and disturbance of such affected protein-protein communication throughout aging in myocardial cells. Methodologies: For our study was used immunohistochemistry, biochemical methods: spectrophotometry, western blotting, immunodetection as well as more sophisticated 2D electrophoresis and mass spectrometry for evaluation protein-protein interactions and specific post-translational modification. Results and Discussion: Mitochondrial stress response to reactive species was evaluated as electron transport chain (ETC) complexes, redox-active molecules, and their possible communication. Protein-protein interactions revealed a strong linkage between age and ETC protein subunits. Redox state was strongly affected in senescent mitochondria with shift in favor of more pro-oxidizing condition within cardiomyocytes. Acute myocardial ischemia and ischemia-reperfusion (IR) injury affected ETC complexes I, II and IV with no change in complex III. Ischemia induced decrease in total antioxidant capacity, MnSOD, GSH and catalase activity with recovery in some extent during reperfusion. While MnSOD protein content was higher in IR group, activity returned to 95% of control. Nitric oxide is one of the biological molecules that can out compete MnSOD for superoxide and produce peroxynitrite. This process is faster than dismutation and led to the 10-fold higher production of nitrotyrosine after IR injury in adult with higher protection in senescent ones. 2D protein profiling revealed 140 mitochondrial proteins, 12 of them with significant changes after IR injury and 36 individual nitrotyrosine-modified proteins further identified by mass spectrometry. Linking these two groups, 5 proteins were altered after IR as well as nitrated, but only one showed massive nitration per lowering content of protein after IR injury in adult. Conclusions: Senescent cells have greater proportion of protein content, which might be modulated by several post-translational modifications. If these protein modifications are connected to functional consequences and protein-protein interactions are revealed, link may lead to the solution. Assume all together, dysfunctional proteostasis can play a causative role and restoration of protein homeostasis machinery is protective against aging and possibly age-related disorders. This work was supported by the project VEGA 1/0018/18 and by project 'Competence Center for Research and Development in the field of Diagnostics and Therapy of Oncological diseases', ITMS: 26220220153, co-financed from EU sources.

Keywords: aging heart, mitochondria, proteomics, redox state

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359 Identification and Quantification of Phenolic Compounds In Cassia tora Collected from Three Different Locations Using Ultra High Performance Liquid Chromatography – Electro Spray Ionization – Mass Spectrometry (UHPLC-ESI-MS-MS)

Authors: Shipra Shukla, Gaurav Chaudhary, S. K. Tewari, Mahesh Pal, D. K. Upreti

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Cassia tora L. is widely distributed in tropical Asian countries, commonly known as sickle pod. Various parts of the plant are reported for their medicinal value due to presence of anthraquinones, phenolic compounds, emodin, β-sitosterol, and chrysophanol. Therefore a sensitive analytical procedure using UHPLC-ESI-MS/MS was developed and validated for simultaneous quantification of five phenolic compounds in leaf, stem and root extracts of Cassia tora. Rapid chromatographic separation of compounds was achieved on Acquity UHPLC BEH C18 column (50 mm×2.1 mm id, 1.7µm) column in 2.5 min. Quantification was carried out using negative electrospray ionization in multiple-reaction monitoring mode. The method was validated as per ICH guidelines and showed good linearity (r2 ≥ 0.9985) over the concentration range of 0.5-200 ng/mL. The intra- and inter-day precisions and accuracy were within RSDs ≤ 1.93% and ≤ 1.90%, respectively. The developed method was applied to investigate variation of five phenolic compounds in the three geographical collections. Results indicated significant variation among analyzed samples collected from different locations in India.

Keywords: Cassia tora, phenolic compounds, quantification, UHPLC-ESI-MS/MS

Procedia PDF Downloads 237
358 Impact of Climate Change on Flow Regime in Himalayan Basins, Nepal

Authors: Tirtha Raj Adhikari, Lochan Prasad Devkota

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This research studied the hydrological regime of three glacierized river basins in Khumbu, Langtang and Annapurna regions of Nepal using the Hydraologiska Byrans Vattenbalansavde (HBV), HVB-light 3.0 model. Future scenario of discharge is also studied using downscaled climate data derived from statistical downscaling method. General Circulation Models (GCMs) successfully simulate future climate variability and climate change on a global scale; however, poor spatial resolution constrains their application for impact studies at a regional or a local level. The dynamically downscaled precipitation and temperature data from Coupled Global Circulation Model 3 (CGCM3) was used for the climate projection, under A2 and A1B SRES scenarios. In addition, the observed historical temperature, precipitation and discharge data were collected from 14 different hydro-metrological locations for the implementation of this study, which include watershed and hydro-meteorological characteristics, trends analysis and water balance computation. The simulated precipitation and temperature were corrected for bias before implementing in the HVB-light 3.0 conceptual rainfall-runoff model to predict the flow regime, in which Groups Algorithms Programming (GAP) optimization approach and then calibration were used to obtain several parameter sets which were finally reproduced as observed stream flow. Except in summer, the analysis showed that the increasing trends in annual as well as seasonal precipitations during the period 2001 - 2060 for both A2 and A1B scenarios over three basins under investigation. In these river basins, the model projected warmer days in every seasons of entire period from 2001 to 2060 for both A1B and A2 scenarios. These warming trends are higher in maximum than in minimum temperatures throughout the year, indicating increasing trend of daily temperature range due to recent global warming phenomenon. Furthermore, there are decreasing trends in summer discharge in Langtang Khola (Langtang region) which is increasing in Modi Khola (Annapurna region) as well as Dudh Koshi (Khumbu region) river basin. The flow regime is more pronounced during later parts of the future decades than during earlier parts in all basins. The annual water surplus of 1419 mm, 177 mm and 49 mm are observed in Annapurna, Langtang and Khumbu region, respectively.

Keywords: temperature, precipitation, water discharge, water balance, global warming

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357 Production of Neutrons by High Intensity Picosecond Laser Interacting with Thick Solid Target at XingGuangIII

Authors: Xi Yuan, Xuebin Zhu, Bojun Li

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This work describes the experiment to produce high-intensity pulsed neutron beams on XingGuangIII laser facility. The high-intensity laser is utilized to drive protons and deuterons, which hit a thick solid target to produce neutrons. The pulse duration of the laser used in the experiment is about 0.8 ps, and the laser energy is around 100 J. Protons and deuterons are accelerated from a 10-μm-thick deuterated polyethylene (CD₂) foil and diagnosed by a Thomson parabola ion-spectrometer. The energy spectrum of neutrons generated via ⁷Li(d,n) and ⁷Li(p,n) reaction when proton and deuteron beams hit a 5-mm-thick LiF target is measured by a scintillator-based time-of-flight spectrometer. Results from the neuron measurements show that the maximum neutron energy is about 12.5 MeV and the neutron yield is up to 2×10⁹/pulse. The high-intensity pulsed neutron beams demonstrated in this work can provide a valuable neutron source for material research, fast neutron induced fission research, and so on.

Keywords: picosecond laser driven, fast neutron, time-of-flight spectrometry, XinggungIII

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356 New Bioactive Compounds from Two Chrysanthemum Saharian Species (Asteraceae) Growing in Algeria

Authors: Zahia Kabouche, Ouissem Gherboudj, Naima Boutaghane, Ahmed Kabouche, Laurence Voutquenne-Nazabadioko

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Chrysanthemum herbs (Asteraceae) are extensively used as food additives and in folk medicine. Anti-cancer, anti-human immunodeficiency virus type 1 (HIV-1), anti-inflammatory, antinociceptive and antiproliferative activities as well as antioxidant effects have been reported for Chrysanthemum species. We report the isolation and identification of flavonoids and new and known terpenoids from the endemic species, C. macrocarpum and C. deserticolum “guertoufa”, used in Algerian Sahara as tea drinks and in “couscous” and soups “Chorba”. Structures of the isolated compounds were established by 1-D and 2-D homo and hetero-nuclear NMR (1H, 13C, COSY, HSQC, HMBC, and NOESY), mass spectrometry, UV and comparison with literature data. C. deserticolum extracts were tested by four methods to identify the antioxidant activity namely, ABTS•+, DPPH• scavenging, CUPRAC and ferrous-ions chelating activity methods. Anti-inflammatory, antinociceptive, antiproliferative and antioxidant activities of C. macrocarpum extracts and isolated compounds are also reported here.

Keywords: Chrysanthemum macrocarpum, C. deserticolum, flavonoids, terpenoids, antioxidant, anti-inflammatory, anti-proliferative

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355 Heavy Metals Concentration in Sediments Along the Ports, Samoa

Authors: T. Imo, F. Latū, S. Aloi, J. Leung-Wai, V. Vaurasi, P. Amosa, M. A. Sheikh

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Contamination of heavy metals in coral reefs and coastal areas is a serious ecotoxicological and environmental problem due to direct runoff from anthropogenic wastes, commercial vessels, and discharge from industrial effluents. In Samoa, the information on the ecotoxicological impact of heavy metals on sediments is limited. This study presents baseline data on the concentration and distribution of heavy metals in sediments collected along the commercial and fishing ports in Samoa. Surface sediment samples were collected within the months of August-October 2013 from the 5 sites along the 2 ports. Sieved sample fractions were used for the evaluation of sediment physicochemical parameters namely pH, conductivity, organic matter, and bicarbonates of calcium. Heavy metal (Cu, Pb) analysis was achieved by flame atomic absorption spectrometry. Two heavy metals (Cu, Pb) were detected from each port with some concentration below the WHO permissible maximum concentration of environment quality standard. The results obtained from this study advocate for further studies regarding emerging threats of heavy metals on the vital marine resources which have significant importance to the livelihood of coastal societies, particularly Small Island States including Samoa.

Keywords: coastal environment, heavy metals, pollution, sediments

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354 Phthalate Exposure among Roma Population in Slovakia

Authors: Miroslava Šidlovská, Ida Petrovičová, Tomáš Pilka, Branislav Kolena

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Phthalates are ubiquitous environmental pollutants well-known because of their endocrine disrupting activity in human organism. The aim of our study was, by biological monitoring, investigate exposure to phthalates of Roma ethnicity group i.e. children and adults from 5 families (n=29, average age 11.8 ± 7.6 years) living in western Slovakia. Additionally, we analysed some associations between anthropometric measures, questionnaire data i.e. socio-economic status, eating and drinking habits, practise of personal care products and household conditions in comparison with concentrations of phthalate metabolites. We used for analysis of urine samples high performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS) to determine concentrations of phthalate metabolites monoethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-iso-butyl phthalate (MiBP), mono(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP), mono(2-ethyl-5-oxohexyl) phthalate (5oxo-MEHP) and mono(2-etylhexyl) phthalate (MEHP). Our results indicate that ethnicity, lower socioeconomic status and different housing conditions in Roma population can affect urinary concentration of phthalate metabolites.

Keywords: biomonitoring, ethnicity, human exposure, phthalate metabolites

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353 Sensitive Determination of Copper(II) by Square Wave Anodic Stripping Voltammetry with Tetracarbonylmolybdenum(0) Multiwalled Carbon Nanotube Paste Electrode

Authors: Illyas Md Isa, Mohamad Idris Saidin, Mustaffa Ahmad, Norhayati Hashim

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A highly selective and sensitive carbon paste electrode modified with multiwall carbon nanotubes and 2,6–diacetylpyridine-di-(1R)–(-)–fenchone diazine tetracarbonylmolybdenum(0) complex was used for determination of trace amounts of Cu(II) using square wave anodic stripping voltammetry (SWASV). The influences of experimental variables on the proposed electrode such as pH, supporting electrolyte, preconcentration potential and time, and square wave parameters were investigated. Under optimal conditions, the proposed electrode showed a linear relationship with concentration in the range of 1.0 × 10–10 to 1.0 × 10– 6 M Cu(II) with a limit of detection 8.0 × 10–11 M. The relative standard deviation (n = 5) for a solution containing 1.0 × 10– 6 M of Cu(II) was 0.036. The presence of various cations (in 10 and 100-folds concentration) did not interfere. Electrochemical impedance spectroscopy (EIS) showed that the charge transfer at the electrode-solution interface was favourable. The proposed electrode was applied for the determination of Cu(II) in several water samples. Results agreed very well with those obtained by inductively coupled plasma-optical emission spectrometry. The modified electrode was then proposed as an alternative for determination of Cu(II).

Keywords: chemically modified electrode, Cu(II), square wave anodic stripping voltammetry, tetracarbonylmolybdenum(0)

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352 Solvent Dependent Triazole-Appended Glucofuranose-Based Fluorometric Sensor for Detection of Au³⁺ Ions

Authors: Samiul Islam Hazarika, Domngam Boje, Ananta Kumar Atta

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It is well familiar that solvents play a significant role in modern chemistry. Solvents can change the reactivity and physicochemical properties of molecules in a solution. Keeping this in mind, we have designed and synthesized a mono-triazolyl-linked pyrenyl-appended xylofuranose derivative for the detection of metal ions with changing solvent systems. The incorporation of a sugar backbone in the sensor increases the water solubility and biocompatibility. The experimental study revealed that the xylofuranose-based fluorescence probe did not exhibit any specific selectivity towards metal ions in acetonitrile (CH₃CN) solvent. Whereas, we revealed that triazole-linked pyrenyl-appended xylofuranose-based fluorescent sensor would exhibit high selectivity and sensitivity towards Au³⁺ ions in CH₃CN-H₂O (1/1, v/v) system. This observation might be explained by the viscosity and polarity differences of CH₃CN and CH₃CN-H₂O solvent systems. The formation of the sensor-Au³⁺ complex was also established by high-resolution mass spectrometry (HRMS) data of the complex.

Keywords: triazole, furanose, fluorometric, solvent dependent

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351 Risk Prediction Based on Heavy Metal Distribution in Groundwater

Authors: Rama Bhattacharyya, S. N. Ojha, Umesh K. Singh

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Anthropogenic control on groundwater chemistry has emerged as a critical concern now-a-days, especially in the industrial areas. In view of this, a comprehensive study on the distribution of the heavy metal in the groundwater was conducted to investigate the impact of urbanization in the aquatic media. Water samples either from well or borehole from Fourty different sites in and around, Durgapur, West Bengal were collected for this purpose. The samples were analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for Calcium (Ca), Cobalt (Co), Chromium (Cr), Copper (Cu), Iron (Fe), Potassium (K), Magnesium (Mg), Manganese (Mn), Sodium (Na), Nickel (Ni), Lead (Pb), Zinc (Zn) content and the levels were compared with WHO specified maximum contaminant level as well as permissible limits given by the Bureau of Indian Standards (BIS). The result obtained from the present study indicates a significant risk to the population of this important emerging ‘smart city’ of eastern India. Because of the toxicity of these metals and the fact that for many tube-wells, dug-wells and bore-wells are the only sources of the water supply for a major fraction of the population in this environment. In this study, an attempt has been made to develop metal contamination risk map.

Keywords: heavy metals, ground water, maximum contamination level, ICP-MS

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350 Electron Impact Ionization Cross-Sections for e-C₅H₅N₅ Scattering

Authors: Manoj Kumar

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Ionization cross sections of molecules due to electron impact play an important role in chemical processes in various branches of applied physics, such as radiation chemistry, gas discharges, plasmas etching in semiconductors, planetary upper atmospheric physics, mass spectrometry, etc. In the present work, we have calculated the total ionization cross sections for Adenine (C₅H₅N₅), a biologically important molecule, by electron impact in the incident electron energy range from ionization threshold to 2 keV employing a well-known Jain-Khare semiempirical formulation based on Bethe and Möllor cross sections. In the non-availability of the experimental results, the present results are in good agreement qualitatively as well as quantitatively with available theoretical results. The present results drive our confidence for further investigation of complex bio-molecule with better accuracy. Notwithstanding, the present method can deduce reliable cross-sectional data for complex targets with adequate accuracy and may facilitate the acclimatization of calculated cross-sections into atomic molecular cross-section data sets for modeling codes and other applications.

Keywords: electron impact ionization cross-sections, oscillator strength, jain-khare semiempirical approach

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349 Investigating Ancient Technology and Ceramic Composition at Al-Khidr Site (Failaka Island, Kuwait): Geochemical Analyses of Bronze Age Pottery by pXRF and Thin-section Petrographic Analyses

Authors: Hasan Ashkanani

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Pottery assemblages from the site of Al-Khidr on Failaka Island, Kuwait, were analysed in order to reconstruct the chemical composition of Bronze Age wares and to build a mineralogical database of Bronze Age pottery dated from Failaka Periods 1–3B (2000–1650 BCE). A total of 145 ceramic sherds from Al-Khidr, as well as reference groups, were analysed by non-destructive portable X-ray fluorescence (pXRF) spectrometry. Preliminarily petrographic thin-section analysis was applied to four samples to reconstruct possible clay paste recipes and to identify raw materials. The results indicate that geochemical analyses can successfully distinguish subgroups within a typological category of ceramic assemblages. The results identified two subgroups within the Al-Khidr typological category: the Dilmun Barbar tradition and the Mesopotamian tradition. Future comparative compositional studies can be conducted to explore other aspects of craft specialisation, such as ceramic technological choices and possibly the influence of sociopolitical units

Keywords: Kuwait archaeology, pottery, pXRF, Dilmun

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348 Proteomic Analysis of Excretory Secretory Antigen (ESA) from Entamoeba histolytica HM1: IMSS

Authors: N. Othman, J. Ujang, M. N. Ismail, R. Noordin, B. H. Lim

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Amoebiasis is caused by the Entamoeba histolytica and still endemic in many parts of the tropical region, worldwide. Currently, there is no available vaccine against amoebiasis. Hence, there is an urgent need to develop a vaccine. The excretory secretory antigen (ESA) of E. histolytica is a suitable biomarker for the vaccine candidate since it can modulate the host immune response. Hence, the objective of this study is to identify the proteome of the ESA towards finding suitable biomarker for the vaccine candidate. The non-gel based and gel-based proteomics analyses were performed to identify proteins. Two kinds of mass spectrometry with different ionization systems were utilized i.e. LC-MS/MS (ESI) and MALDI-TOF/TOF. Then, the functional proteins classification analysis was performed using PANTHER software. Combination of the LC -MS/MS for the non-gel based and MALDI-TOF/TOF for the gel-based approaches identified a total of 273 proteins from the ESA. Both systems identified 29 similar proteins whereby 239 and 5 more proteins were identified by LC-MS/MS and MALDI-TOF/TOF, respectively. Functional classification analysis showed the majority of proteins involved in the metabolic process (24%), primary metabolic process (19%) and protein metabolic process (10%). Thus, this study has revealed the proteome the E. histolytica ESA and the identified proteins merit further investigations as a vaccine candidate.

Keywords: E. histolytica, ESA, proteomics, biomarker

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347 Bioefficacy of Ocimum sanctum on Reproductive Performance of Red Cotton Bug, Dysdercus koenigii (Heteroptera: Pyrrhocoriedae)

Authors: Kamal Kumar Gupta, Sunil Kayesth

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Dysdercus koenigii is serious pest of cotton and other malvaceous crop. Present research work aimed at ecofriendly approach for management of pest by plant extracts. The impact of Ocimum sanctum was studied on reproductive performance of Dysdercus koenigii. The hexane extract of Ocimum leaves was prepared by ‘cold extraction method’. The newly emerged fifth instar nymphs were exposed to the extract of concentrations ranging from 0.1% to 0.00625% by ‘thin film residual method’ for a period of 24h. Reproductive fitness of the adults emerged from the treated nymphs was evaluated by assessing their courtship behaviour, oviposition behaviour, and fertility. The studies indicated that treatment of Dysdercus with the hexane extract of Ocimum altered their courtship behaviour. Consequently, the treated males exhibited less sexual activity, performed fewer mounting attempts, increased time to mate and showed decreased percent successful mating. The females often rejected courting treated male by shaking the abdomen. Similarly, the treated females in many cases remained non-receptive to the courting male. Premature termination of mating in the mating pairs prior to insemination further decreased the mating success of the treated adults. Maximum abbreviation of courtship behaviour was observed in the experimental set up where both the males and the females were treated. Only females which mate successfully were observed for study of oviposition behaviour. The treated females laid lesser number of egg batches and eggs in their life span. The eggs laid by these females were fertile indicating insemination of the female. However, percent hatchability was lesser than control. The effects of hexane extract were dose dependent. Treatment with 0.1% and 0.05% extract altered courtship behaviour. Doses of concentrations less than 0.05% did not affect courtship behaviour but altered the oviposition behaviour and fertility. Significant reduction in the fecundity and fertility was observed in the treatments at concentration as low as 0.00625%. The GCMS analysis of the extract revealed a plethora of phytochemicals including juvenile hormone mimics, and the intermediates of juvenile hormone biosynthesis. Therefore, some of these compounds individually or synergistically impair reproductive behaviour of Dysdercus. Alteration of courtship behaviour and suppression of fecundity and fertility with the help of plant extracts has wide potentials in suppression of pest population and ‘integrated pest management’.

Keywords: courtship behaviour, Dysdercus koenigii, Ocimum sanctum, oviposition behaviour

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346 Natural Radionuclides and Doses Assessment in Soil Samples from Agbara Industrial Estate, Ogun State, Nigeria

Authors: Ayorinde B. Ogunremi, Kehinde A. Adewoyin, Adebamwo Adebayo

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Record of radionuclide concentration in an environment is essential to ensure human safety due to exposure to ionizing radiation. This study aimed at assessing the radionuclide concentration and doses from soil samples in the study area. Twenty soil samples were collected and dried in the oven at 110°C to remove the moisture, pulverized, and sieved. 200 g of each of the samples were sealed in cylindrical sample holders; they were left for four weeks to attain secular equilibrium between ²²⁶Ra and its decay daughters, after which the sample was analyzed using gamma-ray spectrometry. After the well-guided procedure for the calibrations, the analysis of the samples was carried out using a well-calibrated NaI (TI) and well-shielded detector coupled to a computer resident quantum MCA2100 R Multichannel analyzer for 36,000 s. The mean activity concentrations of ⁴⁰K, ²²⁶Ra, and ²³²Th obtained were calculated to be 272.37 ± 33.58, 10.97 ± 3.24, 9.39 ± 2.27 Bqkg-1 respectively. The average absorbed dose obtained was 22.10 nGy/h. The radium equivalent activity (Raeq) was estimated to be 43.27 Bq/kg. The activity concentrations (Bq/kg) were below the recommended values, which are 420, 33, and 45 for ⁴⁰K, ²²⁶Ra, and ²³²Th, respectively. Considering the results, we conclude thus, the radiation level within the estate poses no significant health risk on dwellers and workers.

Keywords: absorbed, effective, multichannel, radionuclide

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345 Synthesis, Characterization, and Biological Evaluation of 1,3,4-Mercaptooxadiazole Ether Derivatives Analogs as Antioxidant, Cytotoxic, and Molecular Docking Studies

Authors: Desta Gebretekle Shiferaw, Balakrishna Kalluraya

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Oxadiazoles and their derivatives with thioether functionalities represent a new and exciting class of physiologically active heterocyclic compounds. Several molecules with these moieties play a vital role in pharmaceuticals because of their diverse biological activities. This paper describes a new class of 1,3,4- oxadiazole-2-thioethers with acetophenone, coumarin, and N-phenyl acetamide residues (S-alkylation), with the hope that the addition of various biologically active molecules will have a synergistic effect on anticancer activity. The structure of the synthesized title compounds was determined by the combined methods of IR, proton-NMR, carbon-13-NMR, and mass spectrometry. Further, all the newly prepared molecules were assessed against their antioxidant activity. Furthermore, four compounds were assessed for their molecular docking interactions and cytotoxicity activity. The synthesized derivatives have shown moderate antioxidant activity compared to the standard BHA. The IC50 of the tilted molecules (11b, 11c, 13b, and 14b) observed for in vitro anti-cancer activities were 11.20, 15.73, 59.61, and 27.66 g/ml at 72-hour treatment time against the A549 cell lines, respectively. The tested compounds' biological evaluation showed that 11b is the most effective molecule in the series.

Keywords: antioxidant activity, cytotoxicity activity, molecular docking, 1, 3, 4-Oxadiazole-2 thioether derivatives

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344 Ecological Risk Aspects of Essential Trace Metals in Soil Derived From Gold Mining Region, South Africa

Authors: Lowanika Victor Tibane, David Mamba

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Human body, animals, and plants depend on certain essential metals in permissible quantities for their survival. Excessive metal concentration may cause severe malfunctioning of the organisms and even fatal in extreme cases. Because of gold mining in the Witwatersrand basin in South Africa, enormous untreated mine dumps comprise elevated concentration of essential trace elements. Elevated quantities of trace metal have direct negative impact on the quality of soil for different land use types, reduce soil efficiency for plant growth, and affect the health human and animals. A total of 21 subsoil samples were examined using inductively coupled plasma optical emission spectrometry and X-ray fluorescence methods and the results elevated men concentration of Fe (36,433.39) > S (5,071.83) > Cu (1,717,28) > Mn (612.81) > Cr (74.52) > Zn (68.67) > Ni (40.44) > Co (9.63) > P (3.49) > Mo > (2.74), reported in mg/kg. Using various contamination indices, it was discovered that the sites surveyed are on average moderately contaminated with Co, Cr, Cu, Mn, Ni, S, and Zn. The ecological risk assessment revealed a low ecological risk for Cr, Ni and Zn, whereas Cu poses a very high ecological risk.

Keywords: essential trace elements, soil contamination, contamination indices, toxicity, descriptive statistics, ecological risk evaluation

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