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Optimization of stabilized leachate treatment using ozone/persulfate in the advanced oxidation process

Abu Amr SS, Aziz HA, Adlan MN

Waste Manag, 2013 Jun;33(6):1434-41.
PMID: 23498721 DOI: 10.1016/j.wasman.2013.01.039

The objective of this study was to investigate the performance of employing persulfate reagent in the advanced oxidation of ozone to treat stabilized landfill leachate in an ozone reactor. A central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the relationships between operating variables, such as ozone and persulfate dosages, pH, and reaction time, to identify the optimum operating conditions. Quadratic models for the following four responses proved to be significant with very low probabilities (<0.0001): COD, color, NH3-N, and ozone consumption (OC). The obtained optimum conditions included a reaction time of 210 min, 30 g/m(3) ozone, 1g/1g COD0/S2O8(2-) ratio, and pH 10. The experimental results were corresponded well with predicted models (COD, color, and NH3-N removal rates of 72%, 96%, and 76%, respectively, and 0.60 (kg O3/kg COD OC). The results obtained in the stabilized leachate treatment were compared with those from other treatment processes, such as ozone only and persulfate S2O8(2-) only, to evaluate its effectiveness. The combined method (i.e., O3/S2O8(2-)) achieved higher removal efficiencies for COD, color, and NH3-N compared with other studied applications. Furthermore, the new method is more efficient than ozone/Fenton in advanced oxidation process in the treatment of the same studied leachate.

Matched MeSH terms: Sulfates/chemistry
Fulltext Performance of combined persulfate/aluminum sulfate for landfill leachate treatment

Abu Amr SS, Alkarkhi AFM, Alslaibi TM, Abujazar MSS

Data Brief, 2018 Aug;19:951-958.
PMID: 29900392 DOI: 10.1016/j.dib.2018.05.111

Although landfilling is still the most suitable method for solid waste disposal, generation of large quantity of leachate is still considered as one of the main environmental problem. Efficient treatment of leachate is required prior to final discharge. Persulfate (S2O82-) recently used for leachate oxidation, the oxidation potential of persulfate can be improved by activate and initiate sulfate radical. The current data aimed to evaluate the performance of utilizing Al2SO4 reagent for activation of persulfate to treat landfill leachate. The data on chemical oxygen demand (COD), color, and NH3-H removals at different setting of the persulfate, Al2SO4 dosages, pH, and reaction time were collected using a central composite design (CCD) were measured to identify the optimum operating conditions. A total of 30 experiments were performed, the optimum conditions for S2O82-/Al2SO4 oxidation process was obtained. Quadratic models for chemical oxygen demand (COD), color, and NH3-H removals were significant with p-value 

Matched MeSH terms: Sulfates
The effect of tocotrienol-rich fraction on the expression of glutathione s-transferase isoenzymes in mice liver

Ahmed Atia, Nadia Salem Alrawaiq, Azman Abdullah

Sains Malaysiana, 2018;47:2799-2809.

Glutathione S-transferase isoenzymes (GSTs) catalyze the conjugation reaction between glutathione and electrophilic
compounds. GSTs are involved in the detoxification of toxic and carcinogenic compounds, thus protecting the body from
toxic injuries. Tocotrienols are part of the vitamin E family and is believed to possess potent antioxidant activity. The
objective of this study was to determine the effect of increasing doses of tocotrienol rich fraction (TRF) supplementation
on liver GSTs gene and protein expression. A total of 30 male ICR white mice were divided into five groups (n=6 for each
group) and given treatment for 14 days through oral supplementation. Groups were divided as follows: - three groups
administered with TRF at doses of 200, 500 and 1000 mg/kg, respectively, a positive control group administered with 100
mg/kg butylated hydroxyanisole (BHA) and a control group administered with only the vehicle (corn oil). At day 15, the
mice were sacrificed and their livers isolated. Total RNA was extracted from the liver and quantitative real-time polymerase
chain reaction (qPCR) assays were performed to analyze GSTs gene expression. Total liver protein was also extracted
and the protein expression of GSTs was determined by Western blotting. The results showed that TRF oral supplementation
caused a significant dose-dependent increase in liver GST isoenzymes gene and protein expression, compared to controls.
In conclusion, TRF oral supplementation for 14 days resulted in increased gene and protein expression of GST isoenzymes
in mice liver dose-dependently, with the highest expression seen in mice treated with 1000 mg/kg TRF.

Matched MeSH terms: Chondroitin Sulfates
Fulltext Evaluation of interface adhesion between silicone soft liners and denture base after immersion with denture cleansers by scanning electron microscope

Aiemeeza Rajali, Siti Fauzza Ahmad

Malaysian Journal of Medicine and Health Sciences, 2020;16(3):148-154.
MyJurnal

Introduction: The compatibility of denture cleanser is crucial in the prevention of failure of adhesion between silicone soft liner and acrylic denture base, thus ensuring the durability of the prosthesis. This scanning electron microscope (SEM) study was to determine the mode of failure and measured the gap formation between silicone soft liners and Polymethylmethacrylate (PMMA) denture base after immersion in denture cleansers. Methods: A total of 135 specimens of PMMA denture base lined with three different silicone soft liners (GC Reline Soft, Mollosil and Tokuyama Sofreliner Tough) were immersed into denture cleansers (Polident® and Stearadent) daily and stored in distilled water at 37±1°C. Specimens were examined and sectioned at 2.5mm and 5.0mm from the margin after 1 day, 30 days and 90 days before analyzed. Results: No significant difference detected in the mode of failure and gap formation after one-day immersion. Adhesive failure was the commonest failure at the margin after 30 days (71.11%) and after 90 days (95.56%). However, 33.33% of specimens showed mixed failure at 5.0mm sectioned after 90 days. A significant difference of gap formation was demonstrated from Mollosil in Steradent at the margin and at 2.5 mm sectioned after 30 days and after 90 days (p

Matched MeSH terms: Sulfates
Control of microbiologically influenced corrosion using ultraviolet radiation

Akrima Abu Bakar, Muhammad Khairool Fahmy Mohd Ali, Norhazilan Md. Noor, Nordin Yahaya, Mardhiah Ismail, Ahmad Safuan A. Rashid

Sains Malaysiana, 2017;46:1323-1331.

Baram Delta Operation had been producing oil and gas since 1960's and serious pipelines failure was reported in the year of 2005. The final investigation has concluded that one of the species of bacteria that has been identified to cause microbiologically influenced corrosion, specifically known as sulfate reducing bacteria (SRB) was found to be one of the potential contributing factors to the incidents. This work investigates the potential use of ultraviolet (UV) radiation to inhibit the SRB consortium that was cultivated from the crude oil in one of the main trunk lines at Baram Delta Operation, Sarawak, Malaysia. The impact of UV exposure to bio-corrosion conditions on carbon steel coupon in certain samples for 28 days was discussed in this study. The samples were exposed to UV radiation based on variations of parameters, namely: time of UV exposure; and power of UV lamp. The significant changes on the amount of turbidity reading and metal loss of the steel coupon were recorded before and after experiment. The results showed that SRB growth has reduced rapidly for almost 90% after the UV exposure for both parameters as compared to the abiotic samples. Metal loss values were also decreased in certain exposure condition. Additionally, field emission scanning electron microscopy (FESEM) coupled with energy dispersive spectroscopy (EDS) was performed to observe the biofilm layer formed on the metal surface after its exposure to SRB. The evidence suggested that the efficiency of UV treatment against SRB growth could be influenced by the particular factors studied

Matched MeSH terms: Sulfates
Determination of the binding constants of modafinil enantiomers with sulfated β-cyclodextrin chiral selector by capillary electrophoresis using three different linear plotting methods

Al Azzam KM, Saad B, Aboul-Enein HY

Electrophoresis, 2010 Sep;31(17):2957-63.
PMID: 20690150 DOI: 10.1002/elps.201000266

Binding constants for the enantiomers of modafinil with the negatively charged chiral selector sulfated-β-CD (S-β-CD) using CE technique is presented. The calculations of the binding constants employing three different linearization plots (double reciprocal, X-reciprocal and Y-reciprocal) were performed from the electrophoretic mobility values of modafinil enantiomers at different concentrations of S-β-CD in the BGE. The highest inclusion affinity of the modafinil enantiomers were observed for the S-enantiomer-S-β-CD complex, in agreement with the computational calculations performed previously. Binding constants for each enantiomer-S-β-CD complex at different temperatures, as well as thermodynamic parameters for binding, were calculated. Host-guest binding constants using the double reciprocal fit showed better linearity (r(2)>0.99) at all temperatures studied (15-30°C) and compared with the other two fit methods. The linear van't Hoff (15-30°C) plot obtained indicated that the thermodynamic parameters of complexation were temperature dependent for the enantiomers.

Matched MeSH terms: Sulfates/chemistry
Fulltext Cytotoxicity and physicochemical characterization of iron-manganese-doped sulfated zirconia nanoparticles

Al-Fahdawi MQ, Rasedee A, Al-Qubaisi MS, Alhassan FH, Rosli R, El Zowalaty ME, et al.

Int J Nanomedicine, 2015;10:5739-50.
PMID: 26425082 DOI: 10.2147/IJN.S82586

Iron-manganese-doped sulfated zirconia nanoparticles with both Lewis and Brønsted acidic sites were prepared by a hydrothermal impregnation method followed by calcination at 650°C for 5 hours, and their cytotoxicity properties against cancer cell lines were determined. The characterization was carried out using X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, Brauner-Emmett-Teller (BET) surface area measurements, X-ray fluorescence, X-ray photoelectron spectroscopy, zeta size potential, and transmission electron microscopy (TEM). The cytotoxicity of iron-manganese-doped sulfated zirconia nanoparticles was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays against three human cancer cell lines (breast cancer MDA-MB231 cells, colon carcinoma HT29 cells, and hepatocellular carcinoma HepG2 cells) and two normal human cell lines (normal hepatocyte Chang cells and normal human umbilical vein endothelial cells [HUVECs]). The results suggest for the first time that iron-manganese-doped sulfated zirconia nanoparticles are cytotoxic to MDA-MB231 and HepG2 cancer cells but have less toxicity to HT29 and normal cells at concentrations from 7.8 μg/mL to 500 μg/mL. The morphology of the treated cells was also studied, and the results supported those from the cytotoxicity study in that the nanoparticle-treated HepG2 and MDA-MB231 cells had more dramatic changes in cell morphology than the HT29 cells. In this manner, this study provides the first evidence that iron-manganese-doped sulfated zirconia nanoparticles should be further studied for a wide range of cancer applications without detrimental effects on healthy cell functions.

Matched MeSH terms: Sulfates/chemistry*
A new sulphated flavone and other phytoconstituents from the leaves of Tetracera indica Merr. and their alpha-glucosidase inhibitory activity

Alhassan AM, Ahmed QU, Latip J, Shah SAA

Nat Prod Res, 2019 Jan;33(1):1-8.
PMID: 29417849 DOI: 10.1080/14786419.2018.1437427

The bioactivity guided fractionation of Tetracera indica leaves crude ethanolic extract has afforded the isolation and characterization of six compounds including a new natural product viz., 5,7-dihydroxyflavone-O-8-sulphate (1) and five known flavonoids (2-6). The structures of the compounds were elucidated using 1D and 2D NMR and HRESIMS spectroscopic analyses. All the isolated compounds were evaluated for their in vitro inhibitory activity against alpha-glucosidase. Compound 1, 5 and 6 showed strong alpha-glucosidase inhibitory activity, 3 and 4 displayed weak activity while compound 2 was inactive. The interactions of the active compounds with alpha-glucosidase were further investigated using molecular docking to confirm their antidiabetic potential.

Matched MeSH terms: Sulfates
Fulltext Modification of Clinoptilolite as a Robust Adsorbent for Highly-Efficient Removal of Thorium (IV) from Aqueous Solutions

Alotaibi AM, Ismail AF

Int J Environ Res Public Health, 2022 Oct 23;19(21).
PMID: 36360653 DOI: 10.3390/ijerph192113774

The natural zeolite has been modified with sulphate and phosphate. The adsorption of thorium from the aqueous solutions by using the natural and modified zeolites has been investigated via a batch method. The adsorbent samples were characterized by X-ray Diffraction (XRD), N2 adsorption-desorption (BET), Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDX). Modification of natural zeolite with sulphate and phosphate was found to increase its adsorption capacity of thorium but reduced its specific surface area (SBET). The adsorption experiments were expressed by Langmuir, Freundlich and Dubinin-Radushkevitch (D-R) isotherm models and the results of adsorption demonstrated that the adsorption of thorium onto the natural and modified zeolites correlated better with the Langmuir isotherm model than with the Freundlich isotherm model. The maximum adsorption capacity (Qo) was determined using the Langmuir isotherm model at 25 °C and was found to be 17.27, 13.83, and 10.21 mg/g for phosphate-modified zeolite, sulfate-modified zeolite, and natural zeolite, respectively. The findings of this study indicate that phosphate-modified zeolite can be utilized as an effective and low-cost adsorbent material for the removal of thorium from aqueous solutions.

Matched MeSH terms: Sulfates
Fulltext Data for the industrial and municipal environmental wastes hazard contaminants assessment with integration of RES2D techniques and Oasis Montaj software

Arifin MH, Kayode JS, Ismail KI, Abdullah M, Embrandiri A, Nazer SM, et al.

Data Brief, 2020 Dec;33:106595.
PMID: 33318980 DOI: 10.1016/j.dib.2020.106595

Industrial, and municipal wastes are part of the main sources of environmental hazards as well as groundwater and surface water pollutions. If not well composed, treated, and safely disposed, it could permeate through the subsurface lithologies by reaching down to the underground water aquifers, particularly in zones of unprotected aquifer units. Pollutants, most especially the landfills leachates that encompassed organic contaminants, ammonia, nitrates, total nitrogen, suspended solids, heavy metals and soluble inorganic salts, i.e., soluble nitrogen, sulphur compound, sulphate and chlorides, could posed undesirable environmental impacts due to inappropriate disposals that may give rise to gaseous fumes and leachate formations. An electrical resistivity geophysical technique utilizing the RES2D no-invasive, cost-effective and rapid method of data collection was integrated with the 3D Oasis Montaj software to approximate the volume of the generated rectangular prism model of the contaminants delineated from mixtures of the industrial, and municipal wastes plumes to be 312,000 m 3.

Matched MeSH terms: Sulfates
Fulltext Predicting the degradation potential of Acid blue 113 by different oxidants using quantum chemical analysis

Asghar A, Bello MM, Raman AAA, Daud WMAW, Ramalingam A, Zain SBM

Heliyon, 2019 Sep;5(9):e02396.
PMID: 31517121 DOI: 10.1016/j.heliyon.2019.e02396

In this work, quantum chemical analysis was used to predict the degradation potential of a recalcitrant dye, Acid blue 113, by hydrogen peroxide, ozone, hydroxyl radical and sulfate radical. Geometry optimization and frequency calculations were performed at 'Hartree Fock', 'Becke, 3-parameter, Lee-Yang-Parr' and 'Modified Perdew-Wang exchange combined with PW91 correlation' levels of study using 6-31G* and 6-31G** basis sets. The Fourier Transform-Raman spectra of Acid blue 113 were recorded and a complete analysis on vibrational assignment and fundamental modes of model compound was performed. Natural bond orbital analysis revealed that Acid blue 113 has a highly stable structure due to strong intermolecular and intra-molecular interactions. Mulliken charge distribution and molecular electrostatic potential map of the dye also showed a strong influence of functional groups on the neighboring atoms. Subsequently, the reactivity of the dye towards the oxidants was compared based on the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy values. The results showed that Acid blue 113 with a HOMO value -5.227 eV exhibits a nucleophilic characteristic, with a high propensity to be degraded by ozone and hydroxyl radical due to their lower HOMO-LUMO energy gaps of 4.99 and 4.22 eV respectively. On the other hand, sulfate radical and hydrogen peroxide exhibit higher HOMO-LUMO energy gaps of 7.92 eV and 8.10 eV respectively, indicating their lower reactivity towards Acid blue 113. We conclude that oxidation processes based on hydroxyl radical and ozone would offer a more viable option for the degradation of Acid blue 113. This study shows that quantum chemical analysis can assist in selecting appropriate advanced oxidation processes for the treatment of textile effluent.

Matched MeSH terms: Sulfates
Fulltext The effect of calcium silicate and ground magnesium limestone (GML) on the chemical characteristics of acid sulfate soil

Azman EA, Ismail R, Ninomiya S, Jusop S, Tongkaemkaew U

PLoS One, 2023;18(9):e0290703.
PMID: 37713375 DOI: 10.1371/journal.pone.0290703

Acid sulfate soil characterized by pyrite (FeS2) which produces high acidity (soil pH < 3.5) and release high amount of Al3+ and Fe2+. Application of 4 t ha-1 Ground Magnesium Limestone (GML), is a common rate used for acid sulfate soil by the rice farmers in Malaysia. Therefore, this study was conducted to evaluate the integral effect of ground magnesium limestone (GML) and calcium silicate and to determine the optimal combination on acid sulfate soils in Malaysia. The acid sulfate soils were incubated under the submerged condition for 120 days with GML (0, 2, 4, 6 t ha-1) in combination with calcium silicate (0, 1, 2, 3 t ha-1) arranged in a Completely Randomized Design (CRD). The soil was sampled after 30, 60, 90 and 120 days of incubation and analyzed for soil pH, exchangeable Al, Ca, Mg, K and available Si. A total of 2 out of 16 combinations met the desired soil requirement for rice cultivation. The desired chemical soil characteristics for rice cultivation are soil pH > 4, exchangeable Al < 2 cmolc Kg-1, exchangeable Ca > 2 cmolc kg-1, exchangeable Mg > 1 cmolc kg-1 and Si content > 43 mg kg-1. The combinations are i) 2 t ha-1 calcium silicate + 2 t ha-1 GML, and ii) 3 t ha-1 calcium silicate + 2 t ha-1 GML, respectively. These combination rates met the desired requirement of soil chemical characteristics for rice cultivation. Soil acidity was reduced by a gradual release of Ca2+ and SiO32- from calcium silicate continuously filling the exchange sites and reducing the potential of extra (free) H+ availability in the soil system. Combination of calcium silicate and GML, shows the ameliorative effect with; i) release of Ca, ii) binding of Al3+ making it inert Al-hydroxides and, iii) bind H+ to produce water molecules.

Matched MeSH terms: Sulfates
Fulltext PH-responsive strontium nanoparticles for targeted gene therapy against mammary carcinoma cells

Bakhtiar A, Chowdhury EH

Asian J Pharm Sci, 2021 Mar;16(2):236-252.
PMID: 33995617 DOI: 10.1016/j.ajps.2020.11.002

Genetic intervention via the delivery of functional genes such as plasmid DNA (pDNA) and short-interfering RNA (siRNA) offers a great way to treat many single or multiple genetic defects effectively, including mammary carcinoma. Delivery of naked therapeutic genes or siRNAs is, however, short-lived due to biological clearance by scavenging nucleases and circulating monocytes. Low cellular internalization of negatively-charged nucleic acids further causes low transfection or silencing activity. Development of safe and effectual gene vectors is therefore undeniably crucial to the success of nucleic acid delivery. Inorganic nanoparticles have attracted considerable attention in the recent years due to their high loading capacity and encapsulation activity. Here we introduce strontium salt-based nanoparticles, namely, strontium sulfate, strontium sulfite and strontium fluoride as new inorganic nanocarriers. Generated strontium salt particles were found to be nanosized with high affinity towards negatively-charged pDNA and siRNA. Degradation of the particles was seen with a drop in pH, suggesting their capacity to respond to pH change and undergo dissolution at endosomal pH to release the genetic materials. While the particles are relatively nontoxic towards the cells, siRNA-loaded SrF2 and SrSO3 particles exerted superior transgene expression and knockdown activity of MAPK and AKT, leading to inhibition of their phosphorylation to a distinctive extent in both MCF-7 and 4T1 cells. Strontium salt nanoparticles have thus emerged as a promising tool for applications in cancer gene therapy.

Matched MeSH terms: Sulfates
Landfill leachate treatment by electrochemical oxidation

Bashir MJ, Isa MH, Kutty SR, Awang ZB, Aziz HA, Mohajeri S, et al.

Waste Manag, 2009 Sep;29(9):2534-41.
PMID: 19523802 DOI: 10.1016/j.wasman.2009.05.004

This study investigated the electrochemical oxidation of stabilized leachate from Pulau Burung semi-aerobic sanitary landfill by conducting laboratory experiments with sodium sulfate Na(2)SO(4) (as electrolyte) and graphite carbon electrodes. The control parameters were influent COD, current density and reaction time, while the responses were BOD removal, COD removal, BOD:COD ratio, color and pH. Na(2)SO(4) concentration was 1 g/L. Experiments were conducted based on a three-level factorial design and response surface methodology (RSM) was used to analyze the results. The optimum conditions were obtained as 1414 mg/L influent COD concentration, 79.9 mA/cm(2) current density and 4 h reaction time. This resulted in 70% BOD removal, 68% COD removal, 84% color removal, 0.04 BOD/COD ratio and 9.1 pH. Electrochemical treatment using graphite carbon electrode was found to be effective in BOD, COD and color removal but was not effective in increasing the BOD/COD ratio or enhancing biodegradability of the leachate. The color intensity of the treated samples increased at low influent COD and high current density due to corrosion of electrode material.

Matched MeSH terms: Sulfates/chemistry
Fulltext Long-term succession in a coal seam microbiome during in situ biostimulation of coalbed-methane generation

Beckmann S, Luk AWS, Gutierrez-Zamora ML, Chong NHH, Thomas T, Lee M, et al.

ISME J, 2019 03;13(3):632-650.
PMID: 30323265 DOI: 10.1038/s41396-018-0296-5

Despite the significance of biogenic methane generation in coal beds, there has never been a systematic long-term evaluation of the ecological response to biostimulation for enhanced methanogenesis in situ. Biostimulation tests in a gas-free coal seam were analysed over 1.5 years encompassing methane production, cell abundance, planktonic and surface associated community composition and chemical parameters of the coal formation water. Evidence is presented that sulfate reducing bacteria are energy limited whilst methanogenic archaea are nutrient limited. Methane production was highest in a nutrient amended well after an oxic preincubation phase to enhance coal biofragmentation (calcium peroxide amendment). Compound-specific isotope analyses indicated the predominance of acetoclastic methanogenesis. Acetoclastic methanogenic archaea of the Methanosaeta and Methanosarcina genera increased with methane concentration. Acetate was the main precursor for methanogenesis, however more acetate was consumed than methane produced in an acetate amended well. DNA stable isotope probing showed incorporation of 13C-labelled acetate into methanogenic archaea, Geobacter species and sulfate reducing bacteria. Community characterisation of coal surfaces confirmed that methanogenic archaea make up a substantial proportion of coal associated biofilm communities. Ultimately, methane production from a gas-free subbituminous coal seam was stimulated despite high concentrations of sulfate and sulfate-reducing bacteria in the coal formation water. These findings provide a new conceptual framework for understanding the coal reservoir biosphere.

Matched MeSH terms: Sulfates/analysis; Sulfates/metabolism
Screening of factors influencing Cu(II) extraction by soybean oil-based organic solvents using fractional factorial design

Chang SH, Teng TT, Ismail N

J Environ Manage, 2011 Oct;92(10):2580-5.
PMID: 21700383 DOI: 10.1016/j.jenvman.2011.05.025

This study aimed to identify the significant factors that give large effects on the efficiency of Cu(II) extraction from aqueous solutions by soybean oil-based organic solvents using fractional factorial design. Six factors (mixing time (t), di-2-ethylhexylphosphoric acid concentration ([D2EHPA]), organic to aqueous phase ratio (O:A), sodium sulfate concentration ([Na(2)SO(4)]), equilibrium pH (pH(eq)) and tributylphosphate concentration ([TBP])) affecting the percentage extraction (%E) of Cu(II) were investigated. A 2(6-1) fractional factorial design was applied and the results were analyzed statistically. The results show that only [D2EHPA], pH(eq) and their second-order interaction ([D2EHPA] × pH(eq)) influenced the %E significantly. Regression models for %E were developed and the adequacy of the reduced model was examined. The results of this study indicate that fractional factorial design is a useful tool for screening a large number of variables and reducing the number of experiments.

Matched MeSH terms: Sulfates
LC-MS/MS simultaneous quantification of apomorphine and its major metabolites in human plasma: Application to clinical comparative bioavailability evaluation for the apomorphine sublingual film and a subcutaneous product

Chen YL, Shi L, Agbo F, Yong SH, Tan PS, Ngounou Wetie AG

J Pharm Biomed Anal, 2020 Oct 25;190:113493.
PMID: 32795778 DOI: 10.1016/j.jpba.2020.113493

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the simultaneous quantification of apomorphine and its metabolites apomorphine sulfate and norapomorphine in human plasma for supporting clinical development of a novel apomorphine sublingual thin film (APL) for the treatment of Parkinson's disease. Analytes and internal standards (IS) were extracted from human plasma by Oasis HLB SPE cartridge, followed by a reversed phase LC-MS/MS analysis using multiple reaction monitoring (MRM) in positive mode (m/z 268 → 237 for apomorphine, 348 → 237 for apomorphine sulfate, and 348 → 237 for norapomorphine). Stable isotope-labeled compounds were used as IS for respective analytes. The validated curve ranges were 0.02-20 ng/mL, 10-1000 ng/mL, and 0.5-20 ng/mL for apomorphine, apomorphine sulfate and norapomorphine, respectively. Extraction recoveries were found to be 73.4 % (apomorphine), 81.1 % (apomorphine sulfate), and 58.6 % (norapomorphine). Established long-term plasma frozen storage stabilities were 504 days at -20 °C and276 days at -60 °C, respectively. The method has been successfully used for analyzing pharmacokinetics (PK) samples collected from a comparative bioavailability study of APL and the marketed apomorphine subcutaneous (s.c.) product Apo-go®. The results demonstrated that the 15-mg APL film administrated via sublingual produced comparable PK characteristics of apomorphine when compared to the commercial product Apo-go (2-mg) via s.c. administration, hence establishing the dose regimen for this sublingual formulation. It was also noticed that the sublingual 15-mg APL film produced a significantly higher apomorphine sulfate metabolite level than the 2-mg s.c. Apo-go, and both treatments yielded a negligible level of norapomorphine metabolite in humans.

Matched MeSH terms: Sulfates
Fulltext Electrochemical Performance of Supercapacitor with Stacked Copper Foils Coated with Graphene Nanoplatelets

Chiam SL, Lim HN, Hafiz SM, Pandikumar A, Huang NM

Sci Rep, 2018 02 15;8(1):3093.
PMID: 29449631 DOI: 10.1038/s41598-018-21572-x

The energy density of conventional supercapacitors is in the range of 6-10 Wh kg-1, which has restricted them from many applications that require devices with long durations. Herein, we report a method for enhancing the energy density of a device through the parallel stacking of five copper foils coated on each side with graphene nanoplatelets. Microporous papers immersed in 2 M aqueous sodium sulphate were used as separators. With a low contact resistance of 0.05 Ω, the supercapacitor yielded an optimum specific energy density and a specific power density of 24.64 Wh kg-1 and 402 W kg-1 at 0.8 V, respectively. The working potential was increased to 2.4 V when three of the supercapacitors were connected in series, forming a tandem device. Its potential for real applications was manifested by the ability to light up a light-emitting diode for 40 s after charging for 60 s.

Matched MeSH terms: Sulfates
Efficacy and role of inulin in mitigation of enteric sulfur-containing odor in pigs

Deng YF, Liu YY, Zhang YT, Wang Y, Liang JB, Tufarelli V, et al.

J Sci Food Agric, 2017 Jun;97(8):2382-2391.
PMID: 27664398 DOI: 10.1002/jsfa.8050

BACKGROUND: The efficacy and role of inulin in the mitigation of enteric sulfur-containing odor gases hydrogen sulfide (H2 S) and methyl mercaptan (CH3 SH) in pigs were examined in this study. Twelve Duroc × Landrace × Yorkshire male finisher pigs (60.7 ± 1.9 kg), housed individually in open-circuit respiration chambers, were randomly assigned to two dietary groups, namely basal diet (control) and basal diet supplemented with 1% (w/w) inulin. At the end of the 45 day experiment, pigs were slaughtered and volatile fatty acid (VFA) concentration, sulfate radical (SO42- ) concentration, population of sulfate-reducing bacteria (SRB) and expression of methionine gamma-lyase (MGL) gene were determined in contents from the caecum, colon (two segments) and rectum. Metabonomic analysis was used to compare differences in biochemical composition, and the Illumina MiSeq procedure to investigate differences in bacterial components, in the different parts of the large intestine between inulin-supplemented and inulin-free (control) groups.
RESULTS: Inulin decreased (P < 0.05) the average daily enteric H2 S and CH3 SH production by 12.4 and 12.1% respectively. The concentrations of acetate, propionate and butyrate in the large intestinal content were significantly increased (P < 0.05) with inulin treatment, whereas valerate concentration and MGL mRNA expression decreased (P < 0.05). The growth of Lactobacillus, Butyrivibrio, Pseudobutyrivibrio, Bifidobacterium and Clostridium butyricum was stimulated, while that of Desulfovibrio, the dominant SRB, was inhibited, and there was an accumulation of SO42- in the large intestinal content of the inulin-supplemented pigs, suggesting that inulin mitigates H2 S generation from the SO42- reduction pathway by reducing the growth of SRB.
CONCLUSION: The results showed that inulin mitigates CH3 SH generation via three methionine degradation metabolic pathways and H2 S generation from two cysteine degradation metabolic pathways, thus resulting in increased synthesis of these two sulfur-containing amino acids in the pig large intestine. © 2016 Society of Chemical Industry.

Matched MeSH terms: Sulfates/metabolism
An assimilatory sulfite reductase, CysI, negatively regulates the dormancy of Microbulbifer aggregans CCB-MM1T

Diyana T, Furusawa G

J Basic Microbiol, 2021 Dec;61(12):1124-1132.
PMID: 34796964 DOI: 10.1002/jobm.202100198

Sulfur is one of the common and essential elements of all life. Sulfate, which is a major source of sulfur, plays an important role in synthesizing sulfur-containing amino acids, such as cysteine and methionine, organic compounds essential to all living organisms. Some investigations reported that the assimilatory sulfate reduction pathway (ASRP) involved in cysteine synthesis is crucial to entering bacterial dormancy in pathogens. Our previous investigation reported that the halophilic marine bacterium, Microbulbifer aggregans CCB-MM1T , possesses an ASRP and the dissimilatory sulfate reduction pathway (DSRP). The bacterium might use DSRP to generate energy required for entering its dormant. However, the role of the ASRP in the dormancy of M. aggregans CCB-MM1T was so far unknown. In this study, we found that genes involved in ASRP were downregulated in the dormancy. The disruption of the gene encoding an assimilatory sulfite reductase, cysI, suppressed a completely dormant state under low nutrient conditions. In addition, the cysI mutant showed cell aggregation at the middle-exponential phase under high nutrient conditions, indicating that the mutation might be stimulated to enter the dormancy. The wild-type phenotype of the bacterium was recovered by the addition of cysteine. These results suggested that cysteine concentration may play an important role in inducing the dormancy of M. aggregans.

Matched MeSH terms: Sulfates

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