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Fulltext Effects of Oxidation of Human Serum Albumin on the Binding of Aripiprazole

Sakurama K, Nishi K, Chuang VTG, Hashimoto M, Yamasaki K, Otagiri M

Biol Pharm Bull, 2020;43(6):1023-1026.
PMID: 32475912 DOI: 10.1248/bpb.b20-00205

Aripiprazole (ARP) is one of antipsychotics and binds to human serum albumin (HSA) with a high affinity. In this study, we investigated the binding characteristics of ARP to oxidized HSA as observed in chronic disease conditions. Oxidized HSAs were prepared using chloramine-T (CT-HSA) or metal-catalyzed oxidation system (MCO-HSA) in vitro, respectively. An increase in the carbonyl content was confirmed in oxidized HSAs. From the results of circular dichroism (CD) and tryptophan fluorescence spectra, no significant structural change of oxidized HSAs was observed. These results indicate that prepared HSAs are mildly oxidized and well reflects the status of HSA during chronic diseases. However, oxidized HSAs were observed to have a significant decrease in binding to ARP. The results of the induced CD spectrum suggested that ARP bound to oxidized HSAs with a similar orientation. These results suggest that oxidation of HSA during chronic disease state significantly affected the microenvironment of the binding site for ARP and binding capacity of HSA to ARP.

Matched MeSH terms: Oxidation-Reduction
Fulltext SYNTHESIS AND CHARACTERIZATION OF TiO2/ZnO-EPOXY BEADS AND THEIR PERFORMANCE FOR THE DEGRADATION OF DYE

MOHAMAD HANIF AKMAL HUSSIN, WAN RAFIZAH WAN ABDULLAH, MOHAMAD AWANG

UMT Journal of Undergraduate Research, 2020;2(2):9-14.
MyJurnal

Semiconductor oxides such as titanium dioxide (TiO2) and zinc oxide (ZnO) are used as the photocatalyst for removing contaminants. In addition, TiO2 and ZnO nanoparticles in the suspension form makes it difficult to be recovered and recycled. This study was conducted to investigate the efficiency of immobilizing TiO2 and ZnO nanoparticles in epoxy beads. The immobilization process using different ratios of photocatalysts TiO2/ZnO (1:0, 3:1, 1:1, 1:3 and 0:1) fixed on epoxy material. These epoxy beads were used for dye removal in photocatalysis using methylene blue (MB) solution at a concentration of 10mg/L. Besides, epoxy beads also characterized using scanning electron microscope (SEM), attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and thermogravimetric analysis (TGA). The results showed that the highly recommended epoxy bead is 3:1 ratio of TiO2/ZnO because it has good performance in dye degradation that proved from reducing concentration of MB to 2.4mg/L (76%). However, TiO2/ZnO characterization of 3:1 by SEM show on the surface the particle are found to be spherical in shape which is relatively high efficiency for the degradation, ATR-FTIR pattern in broad band 4000 cm-1 - 400cm-1 which correspond to hydroxyl stretching to be adsorbed at peak (474.49 cm-1 - 3722.61cm-1) respectively to the optimum for the degradation and TGA rate of change are 5mg to 2.5mg that residue (49.78%) due to decomposition or oxidation from mass loss. These findings are very effective and economical technique to be cost saving and highly efficient photocatalyst.

Matched MeSH terms: Oxidation-Reduction
Fulltext SOLAR PHOTOCATALYTIC EFFICIENCY OF ZINC OXIDE FOR WATER DECONTAMINATION

FARAH EILYANA MOHAMED

UMT Journal of Undergraduate Research, 2019;1(1):92-102.
MyJurnal

Solar photocatalysis is a green technology that takes advantage of sustainable solar energy for enhancing oxidation process of numerous harmful water contaminants. In this study, a custom solar driven zinc oxide (ZnO)-mediated photocatalytic system was developed and its efficiency to remove organic contaminants as well as to disinfect selected bacteria was investigated. Methylene blue (MB) dye was used as the model organic contaminant, while Escherichia coli(E.coli) was used as the model fecal coliform bacteria in contaminated water. A series of photodegradation experiments were conducted on water contaminated with either 10 mg/L of MB or ~1010CFU/ml of E.coli. The experiments were completed under sunlight irradiation in the presence of 1 g/L of nano ZnO photocatalyst for up to 6 hours. Using a solar thermal collector, the photoreactor operated in the temperature range of 25 to 50 oC. The findings revealed that the combination of solar thermal with solar photocatalysis usingZnO intensified the degradation of MB and disinfection of E.coli. 98.08% of MB dye and 99.99% of E.coliwere successfully removed from the water within the first 3 hours of treatment. Almost complete removal was eventually achieved after 6 hours of treatment. It is therefore suggested that ZnO-based solar photocatalytic system developed in this study is highly efficient at enhancing water decontamination process.

Matched MeSH terms: Oxidation-Reduction
Rapid Nucleation of Reduced Graphene Oxide-Supported Palladium Electrocatalysts for Methanol Oxidation Reaction

Ng JC, Tan CY, Ong BH, Matsuda A, Basirun WJ, Tan WK, et al.

J Nanosci Nanotechnol, 2019 Nov 01;19(11):7236-7243.
PMID: 31039881 DOI: 10.1166/jnn.2019.16717

Small sized electrocatalysts, which can be obtained by rapid nucleation and high supersaturation are imperative for outstanding methanol oxidation reaction (MOR). Conventional microwave synthesis processes of electrocatalysts include ultrasonication, stirring, pH adjustment, and microwave irradiation of the precursor mixture. Ethylene glycol (EG), which serves as a reductant and solvent was added during the ultrasonication or stirring stage. However, this step and pH adjustment resulted in unintended multi-stage gradual nucleation. In this study, the microwave reduction approach was used to induce rapid nucleation and high supersaturation in order to fabricate small-sized reduced graphene oxide-supported palladium (Pd/rGO) electrocatalysts via the delayed addition of EG, elimination of the pH adjustment step, addition of sodium carbonate (Na₂CO₃), prior microwave irradiation of the EG mixed with Na₂CO₃, and addition of room temperature precursor mixture. Besides its role as a second reducing agent, the addition of Na₂CO₃ was primarily intended to generate an alkaline condition, which is essential for the high-performance of electrocatalysts. Moreover, the microwave irradiation of the EG and Na₂CO₃ mixture generated highly reactive free radicals that facilitate rapid nucleation. Meanwhile, the room temperature precursor mixture increased supersaturation. Results showed improved electrochemically active surface area (78.97 m² g-1, 23.79% larger), MOR (434.49 mA mg-1, 37.96% higher) and stability.

Matched MeSH terms: Oxidation-Reduction
Geoaccumulation Index and Enrichment Factor of Arsenic in Surface Sediment of Bukit Merah Reservoir, Malaysia

Abdullah MIC, Sah ASRM, Haris H

Trop Life Sci Res, 2020 Oct;31(3):109-125.
PMID: 33214859 DOI: 10.21315/tlsr2020.31.3.8

An investigation study was conducted in Bukit Merah Reservoir (BMR) for the assessment of arsenic concentration in the surface sediment in 23 sampling stations. The sediment samples were digested and analysed for arsenic using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Sediment parameters such as pH (4.42 ± 0.71), redox potential (121.77 ± 42.45 mV), conductivity (205.7 ± 64.07 μS cm-1) and organic matter (25.35 ± 9.34%) were also examined. The main objectives of this study are to determine the arsenic distribution and concentration and at the same time to assess the enrichment of arsenic using the geoaccumulation index (I
geo
) and enrichment factor (EF). This study shows the total arsenic concentration in the surface sediment of BMR is 4.302 ± 2.43 mg kg-1 and found to be below the threshold value of Canadian Interim Sediment Quality Guidelines (ISQG). High arsenic concentration is recorded near the southern part of the lake where anthropogenic activities are prevalent. Based on I
geo
, 13% of sampling stations are categorised as moderately polluted, 52.2% as unpolluted to moderately polluted and the rest is categorised as unpolluted. EF shows 78.3% stations are classified as extremely high enrichment and the rest as very high enrichment. This finding provides important information on the status of arsenic contamination in BMR and creating awareness concerning the conservation and management of the reservoir in the future.

Matched MeSH terms: Oxidation-Reduction
The application of Artocarpus integer seed lectin-M in the detection and isolation of selective human serum acute-phase proteins and immunoglobulins

Hashim OH, Ahmad F, Shuib AS

Immunol Invest, 2001 May;30(2):131-41.
PMID: 11465670

Champedak (Artocarpus integer) lectin-M is a lectin with high specificity and affinity for the core-mannosyl residues of the N-linked oligosaccharides of glycoproteins. We have studied the interaction of the champedak seed lectin with human serum glycoproteins that were resolved by 2-dimensional (2-D) gel electrophoresis. The lectin demonstrated strong interaction with haptoglobin beta chain, orosomucoid, alpha1-antitrypsin, alpha2-HS glycoprotein, transferrin, hemopexin, alpha1B-glycoprotein, and the heavy chains of IgA, IgM and IgG of the human serum. With exceptions of the heavy chains of the immunoglobulins and alpha1B-glycoprotein, all the other lectin-M-probed glycopeptides are acute-phase proteins. The use of champedak lectin-M to probe for serum glycoproteins that were separated in a 2-D gel electrophoresis and Western blotting technique may be conveniently applied to analyse the acute-phase and humoral immune responses simultaneously. Subjecting human serum to immobilised-lectin-M affinity chromatography was able to isolate intact haptoglobin, alpha1-antitrypsin, alpha1B-glycoprotein, hemopexin and IgA.

Matched MeSH terms: Oxidation-Reduction
Fulltext Preparation and thermal behaviour of acrylonitrile (an)/ethyl acrylate (ea) copolymer and acrylonitrile (an)/ethyl acrylate (ea)/fumaronitrile (fn) terpolymer as precursors for carbon fibre

Siti Nurul Ain Md. Jamil, Rusil Daik, Ishak Ahmad

Pertanika Journal of Science & Technology, 2010;18(2):-.
MyJurnal

Redox polymerization of acrylonitrile (AN) with ethyl acrylate (EA) and fumaronitrile (FN), as comonomer and termonomer respectively, were carried out using sodium bisulfite (SBS) and potassium persulphate (KPS) as initiators at 40°C. The actual composition of monomers in copolymers and terpolymers has been characterized by gas chromatography (GC). The effects of EA and FN on the glass transition temperature (Tg) and stabilization temperature have been studied by Differential Scanning Calorimetry (DSC). The degradation behaviour and char yield were obtained by thermogravimetric analysis. Meanwhile, incorporation of 10 mol% of EA in homoPAN system was found to greatly reduce Tg to 66°C as compared to that of the homoPAN (Tg=105°C). The initial cyclization temperature (Ti) was found to be higher (264°C) in comparison to that of homoPAN (246°C). In addition, the incorporation of EA was also shown to reduce the char yield of copolymer to 40%. When FN was incorporated as termonomer, the char yield of poly(AN/EA/ FN) 90/4/6 increased up to 44% after the heat treatment with the lowest Ti (241°C).

Matched MeSH terms: Oxidation-Reduction
Fulltext Evaluation of the antioxidant potential of some Malaysian herbal aqueous extracts as compared with synthetic antioxidants and ascorbic acid in cakes

International Food Research Journal, 2011;18(2):583-587.
MyJurnal

Efficacy of some Malaysian herbal aqueous extracts, BHA/BHT (synthetic antioxidants) and ascorbic acid in retarding oxidative rancidity was tested with cakes. The development of lipid oxidation products during 15 days at room temperature was evaluated by means of Peroxide Value (PV) and Thiobarbituric acidreactive substances (TBARS) value. The six formulations consists of control sample (cake without addition of antioxidant) (F1), cake added with curry leaves extract (F2), cake incorporated with kesum leaves extract (F3), cake added with tenggek burung leaves extract (F4), cake incorporated with ascorbic acid (F5) and cake added with BHA/BHT (F6). Formulation with the incorporation of tenggek burung leaves extract showed powerful oxidative stability effect compared to the formulations with othe plant extracts and control sample. However, cakes with BHA/BHT showed the strongest oxidative stability throughout the storage period. Therefore, it is suggested that tenggek burung leaves extract can be added into the food system for effectiveness as antioxidant to prolong the shelf life of the product.

Matched MeSH terms: Oxidation-Reduction
Reduction and biofixation of carbon dioxide in palm oil mill effluent using developed microbial granules containing photosynthetic pigments

Najib MZM, Salmiati, Ujang Z, Salim MR, Ibrahim Z, Muda K

Bioresour Technol, 2016 Dec;221:157-164.
PMID: 27639234 DOI: 10.1016/j.biortech.2016.08.119

The developed microbial granules containing photosynthetic pigments had successfully achieved approximately 18-21% of carbon dioxide (CO2) removal in POME for one complete SBR cycle. Also, the granules had reached CO2 removal at 15-29% within 24h and removal of 25% after 5 days. Both results were inconsistent possibly due to the slow mass transfer rate of CO2 from gas to liquid as well as the simultaneous effect of CO2 production and respiration among the microbes. Furthermore, results showed the removal of CO2 from air increases proportionally with the CO2 removed in liquid. The CO2 biofixation of granules attained was approximately 0.23g/L/day for a week. Using the regression model, the removal of CO2 between liquid and gas, CO2 biofixation rate were highly correlated with the treatment time. A statistically significant relationship was obtained between CO2 concentration in liquid, biomass productivity and treatment time for the CO2 biofixation rate of the granules.

Matched MeSH terms: Oxidation-Reduction
Proteomics Analysis Revealed that Crosstalk between Helicobacter pylori and Streptococcus mitis May Enhance Bacterial Survival and Reduces Carcinogenesis

Khosravi Y, Loke MF, Goh KL, Vadivelu J

Front Microbiol, 2016;7:1462.
PMID: 27695448

Helicobacter pylori is the dominant species of the human gastric microbiota and is present in the stomach of more than half of the human population worldwide. Colonization by H. pylori causes persistent inflammatory response and H. pylori-induced gastritis is the strongest singular risk factor for the development of gastric adenocarcinoma. However, only a small proportion of infected individuals develop malignancy. Besides H. pylori, other microbial species have also been shown to be related to gastritis. We previously reported that interspecies microbial interaction between H. pylori and S. mitis resulted in alteration of their metabolite profiles. In this study, we followed up by analyzing the changing protein profiles of H. pylori and S. mitis by LC/Q-TOF mass spectrometry to understand the different response of the two bacterial species in a multi-species micro-environment. Differentially-expressed proteins in mono- and co-cultures could be mapped into 18 biological pathways. The number of proteins involve in RNA degradation, nucleotide excision repair, mismatch repair, and lipopolysaccharide (LPS) biosynthesis were increased in co-cultured H. pylori. On the other hand, fewer proteins involve in citrate cycle, glycolysis/ gluconeogenesis, aminoacyl-tRNA biosynthesis, translation, metabolism, and cell signaling were detected in co-cultured H. pylori. This is consistent with our previous observation that in the presence of S. mitis, H. pylori was transformed to coccoid. Interestingly, phosphoglycerate kinase (PGK), a major enzyme used in glycolysis, was found in abundance in co-cultured S. mitis and this may have enhanced the survival of S. mitis in the multi-species microenvironment. On the other hand, thioredoxin (TrxA) and other redox-regulating enzymes of H. pylori were less abundant in co-culture possibly suggesting reduced oxidative stress. Oxidative stress plays an important role in tissue damage and carcinogenesis. Using the in vitro co-culture model, this study emphasized the possibility that pathogen-microbiota interaction may have a protective effect against H. pylori-associated carcinogenesis.

Matched MeSH terms: Oxidation-Reduction
Fulltext Response of Streptococcus Zooepidemicus to oxidative stress in hyaluronic acid fermentation

Mashitah, M.D., Masitah, H., Ramachandran, K.B.

Pertanika Journal of Science & Technology, 2009;17(1):-.
MyJurnal

Streptococcus zooepidemicus (SZ) is an aerotolerant bacteria and its ability to survive under reactive oxidant raises the question of the existence of a defense system against oxidative stress. As a characteristic of lactic acid bacteria, Streptococcus lacks an ordinary anti-oxidative stress enzyme, catalases and an electron transport chain. Whether this bacterium resists oxidative stress prior to an exposure to a higher level of an oxidizing agent H2O2 in hyaluronic acid fermentation is not known. This paper describes that Streptococcus cells, once treated with lower concentrations of H2O2 (i.e. 0.25, 0.50 and 1.0 mM) at least, were prepared for a subsequent higher concentrations of H2O2 such as 20.5 and 100 mM. At low concentrations (i.e. 0.25, 0.50 and 1.0 mM), H2O2 was found to act as a stimulant for HA synthesis, but it became toxic if presented at a very high level (100 mM H2O2). The highest HA yield to glucose consumed (YHAtotal/glu) was 0.017 gg-1 for the cells pre-treated with 0 mM of H2O2, and then exposed to 20.5 mM H2O2. Thus, this implied that this bacteria might possess a defense mechanism against oxidative stress and that this system was inducible.

Matched MeSH terms: Oxidation-Reduction
Fulltext Cytotoxicity of gypsum-based biomaterial for direct pulp capping using stem cells from human exfoliated deciduous teeth

Subhi H, Reza F, Husein A, Nurul AA

J Conserv Dent, 2018 4 10;21(1):21-25.
PMID: 29628642 DOI: 10.4103/JCD.JCD_86_17

Aim: The aim of this study was to evaluate the cytotoxicity effects of experimental gypsum-based biomaterial prepared with various concentrations of chitosan (Gyp-CHT).
Materials and Methods: The study was performed using cell viability assay for mitochondrial dehydrogenase activity in stem cells from human exfoliated deciduous teeth (SHED), after 1, 2, and 3 days of exposure to the biomaterial extracts of varying concentrations. Differences in mean cell viability values were assessed by one-way analysis of variance, followed by Dunnett T3 post hoc test for multiple comparisons (P < 0.05).
Results: The cell viability to Gyp-CHT in low extract concentrations was statistically similar to that of the control and different from that of high extract concentrations. Gyp-5% CHT showed the highest percentage of cell viability with 110.92%, 108.56%, and 109.11%. The cell viability showed a tendency toward increment with low extract concentration and no constant effect of CHT on cell viability toward higher or lower.
Conclusions: Gyp-CHT biomaterial has no cytotoxic effects on the cultured SHED.

Matched MeSH terms: Oxidation-Reduction
Optimization of Bleaching Parameters in Refining Process of Kenaf Seed Oil with a Central Composite Design Model

Chew SC, Tan CP, Nyam KL

J Food Sci, 2017 Jul;82(7):1622-1630.
PMID: 28608553 DOI: 10.1111/1750-3841.13758

Kenaf seed oil has been suggested to be used as nutritious edible oil due to its unique fatty acid composition and nutritional value. The objective of this study was to optimize the bleaching parameters of the chemical refining process for kenaf seed oil, namely concentration of bleaching earth (0.5 to 2.5% w/w), temperature (30 to 110 °C) and time (5 to 65 min) based on the responses of total oxidation value (TOTOX) and color reduction using response surface methodology. The results indicated that the corresponding response surface models were highly statistical significant (P < 0.0001) and sufficient to describe and predict TOTOX value and color reduction with R2 of 0.9713 and 0.9388, respectively. The optimal parameters in the bleaching stage of kenaf seed oil were: 1.5% w/w of the concentration of bleaching earth, temperature of 70 °C, and time of 40 min. These optimum parameters produced bleached kenaf seed oil with TOTOX value of 8.09 and color reduction of 32.95%. There were no significant differences (P > 0.05) between experimental and predicted values, indicating the adequacy of the fitted models.

Matched MeSH terms: Oxidation-Reduction
Modification of oil palm fronds lignin by incorporation of m-cresol for improving structural and antioxidant properties

Sa'don NA, Rahim AA, Ibrahim MNM, Brosse N, Hussin MH

Int J Biol Macromol, 2017 Nov;104(Pt A):251-260.
PMID: 28602987 DOI: 10.1016/j.ijbiomac.2017.06.038

Lignin extracted from oil palm fronds (OPF) underwent chemical modification by incorporating m-cresol into the lignin matrix. This study reports on the physicochemical properties and antioxidant activity of unmodified autohydrolyzed ethanol organosolv lignin (AH EOL) and the modified autohydrolyzed ethanol organosolv lignin (AHC EOL). The lignin samples were analyzed by FTIR, 1H and 13C NMR spectroscopy, 2D NMR: HSQC spectroscopy, CHN analysis, molecular weight distribution analysis; GPC and thermal analysis; DSC and TGA. The lignin modification has reduced the hydrophobicity of its complex structure by providing better quality lignin with smaller fragments and higher solubility rate in water (DAHCEOL: 42%>DAHEOL: 25%). It was revealed that the modification of lignin has improved their structural and antioxidant properties, thus venture their possible applications.

Matched MeSH terms: Oxidation-Reduction
Plant extract as environmental-friendly green catalyst for the reduction of hexavalent chromium in tannery effluent

Johnson P, Loganathan C, Krishnan V, Sakayanathan P, Raji V, Vijayan S, et al.

Environ Technol, 2018 Jun;39(11):1376-1383.
PMID: 28488473 DOI: 10.1080/09593330.2017.1329355

The aqueous extract of various plants like Coriandrum sativum (AECS), Alternanthera tenella colla (AEAT), Spermacoce hispida (AESH) and Mollugo verticillata (AEMV) was studied for its hexavalent chromium (CrVI) reduction property. Even though antioxidant activity was present, AEAT, AESH and AEMV did not reduce CrVI. AECS showed rapid and dose-dependent CrVI reduction. The efficient reduction of 50 mg/L of CrVI using AECS was attained in the presence of 250 µg/mL of starting plant material, incubating the reaction mixture at pH 2, 30°C and agitation at 190 rpm. Under such conditions, about 40 mg/L of CrVI was reduced at 3 h of incubation. FT-IR analysis revealed the involvement of phenols, alcohols, alpha-hydroxy acid and flavonoids present in the AECS for the CrVI reduction. These results indicate that not all the plant extracts with rich antioxidants are capable of reducing CrVI. Using the conditions standardized in the present study, AECS reduced about 80% of CrVI present in the tannery effluent. These results signify the application of AECS as an eco-friendly method in the wastewater treatment.

Matched MeSH terms: Oxidation-Reduction
Self-assembled heteropolyacid on nitrogen-enriched carbon nanofiber for vanadium flow batteries

Etesami M, Abouzari-Lotf E, Sha'rani SS, Miyake M, Moozarm Nia P, Ripin A, et al.

Nanoscale, 2018 Jul 13;10(27):13212-13222.
PMID: 29971298 DOI: 10.1039/c8nr02450b

A novel polyoxometalate-based electrode was developed by incorporating phosphotungstic acid (PWA) in nylon-6,6 nanofiber, followed by carbonization. The developed PWA-carbon nanofiber (PWA-CNF) showed the characteristics of the dual-scale porosity of micro- and mesoporous substrate with surface area of around 684 m2 g-1. The compound exhibited excellent stability in vanadium electrolyte and battery cycling. Evaluation of electrocatalytic properties toward V2+/V3+ and VO2+/VO2+ redox couples indicated promising advantages in electron transfer kinetics and increasing energy efficiency, particularly for the VO2+/VO2+ couple. Moreover, the developed electrode exhibited substantially improved energy efficiency (14% higher than that of pristine carbon felt) in the single cell vanadium redox flow battery. This outstanding performance was attributed to high surface area and abundant oxygen-containing linkages in the developed electrode.

Matched MeSH terms: Oxidation-Reduction
Fulltext CsoR metalloregulatory protein: function, mechanism and relevance

Mangavelu, Ashwaani, Yahaya M. Normi, Leow, Adam Thean Chor, Mohd Shukuri Mohammad Ali, Raja Noor Zaliha Raja Abd. Rahman

The Pertanika Journal of Scholarly Research Reviews, 2017;3(1):24-31.
MyJurnal

Transition metals are required constituent in bacterial metabolism to assist in some enzymatic reactions. However, intracellular accumulations of these metal ions are harmful to the bacteria as it can trigger unnecessary redox reactions. To overcome this condition, metalloregulatory proteins assist organisms to adapt to sudden elevated and deprived metal ion concentration in the environment via metal homeostasis. CsoR protein is a copper(I) [Cu(I)] sensing operon repressor that is found to be present in all major classes of eubacteria. This metalloregulatory protein binds to the operator region in its apo state under Cu(I) limiting condition and detaches off from the regulatory region when it binds to the excess cytosolic Cu(I) ion, thus derepressing the expression of genes involved in Cu(I) homeostasis. CsoR proteins exist in dimeric and tetrameric states and form certain coordination geometries upon attachment with Cu(I). Certain CsoR proteins have also been found to possess the ability to bind to other types of metals with various binding affinities in some Gram positive bacteria. The role of this metalloregulatory protein in host pathogen interaction and its relation to bacterial virulence are also discussed.

Matched MeSH terms: Oxidation-Reduction
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: Oxidation-Reduction
Characterisation of electrospun gelatine nanofibres encapsulated with Moringa oleifera bioactive extract

Hani NM, Torkamani AE, Azarian MH, Mahmood KW, Ngalim SH

J Sci Food Agric, 2017 Aug;97(10):3348-3358.
PMID: 27981649 DOI: 10.1002/jsfa.8185

BACKGROUND: Drumstick (Moringa oleifera) leaves have been used as a folk herbal medicine across many cultures since ancient times. This is most probably due to presence of phytochemicals possessing antioxidant properties, which could retard oxidative stress, and their degenerative effect. The current study deals with nanoencapsulation of Moringa oleifera (MO) leaf ethanolic extract within fish sourced gelatine matrix using electrospinning technique.
RESULTS: The total phenolic and flavonoid content, radical scavenging (IC50 ) and metal reducing properties were 67.0 ± 2.5 mg GAE g-1 sample 32.0 ± 0.5 mg QE g-1 extract, 0.08 ± 0.01 mg mL-1 and 510 ± 10 µmol eq Fe(II) g-1 extract, respectively. Morphological and spectroscopic analysis of the fibre mats confirmed successful nanoencapsulation of MO extract within defect free nanofibres via electrospinning process. The percentage encapsulation efficiency (EE) was between 80% and 85%. Furthermore, thermal stability of encapsulated fibres, especially at 3% and 5% of core loading content, was significantly improved. Toxicological analysis revealed that the extract in its original and encapsulated form was safe for oral consumption.
CONCLUSION: Overall, the present study showed the potential of ambient temperature electrospinning process as a safe nanoencapsulation method, where MO extract retained its antioxidative capacities. © 2016 Society of Chemical Industry.

Matched MeSH terms: Oxidation-Reduction
Quantification of selected steroid hormones (17β-Estradiol and 17α-Ethynylestradiol) in wastewater treatment plants in Klang Valley (Malaysia)

Yien Fang T, Praveena SM, Aris AZ, Syed Ismail SN, Rasdi I

Chemosphere, 2019 Jan;215:153-162.
PMID: 30316157 DOI: 10.1016/j.chemosphere.2018.10.032

Steroid estrogens, such as 17β-estradiol (E2) and 17α-ethynylestradiol (EE2) are potent and were categorized as "Watch List" in Directive 2013/39/EU because of their potential risks to aquatic environment. Commercialized enzyme-linked immunosorbent assay (ELISA) kits have been used to quantify steroid estrogens in wastewater samples due to their simplicity, rapid, cost-effectiveness, and validated assays. Hence, this study aims to determine the occurrence and removal of steroid hormones in Malaysian wastewater treatment plants (WWTPs) by ELISA, to identify the association of removal efficiency (E2 and EE2) with respect to WWTPs operating conditions, and to assess the potential risks of steroid estrogens to aquatic environment and human. Results showed E2 concentration ranged from 88.2 ± 7.0 ng/L to 93.9 ± 6.9 ng/L in influent and 35.1 ± 17.3 ng/L to 85.2 ± 7.6 ng/L in effluent, with removal of 6.4%-63.0%. The EE2 concentration ranged from 0.2 ± 0.2 ng/L to 4.9 ± 6.3 ng/L in influent and 0.02 ± 0.03 ng/L to 1.0 ± 0.8 ng/L in effluent, with removal of 28.3-99.3%. There is a correlation between EE2 removal with total suspended solid (TSS) and oxidation reduction potential (ORP), and was statistically significant. Despite the calculated estrogenic activity for E2 and EE2 was relatively high, dilution effects could lower estrogenic response to aquatic environment. Besides, these six selected WWTPs have cumulative RQ values below the allowable limit, except WWTP 1. Relatively high precipitation (129-218 mm) could further dilute estrogens concentration in the receiving river. These outputs can be used as quantitative information for evaluating the occurrence and removal of steroid estrogens in Malaysian WWTPs.

Matched MeSH terms: Oxidation-Reduction

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