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  1. Al-Mekhlafi NA, Shaaria K, Abas F, Jeyaraj EJ, Stanslas J, Khalivulla SI, et al.
    Nat Prod Commun, 2013 Apr;8(4):447-51.
    PMID: 23738449
    In the present study phytochemical investigation of the methanol extract of the stem bark of Horsfieldia superba led to the isolation of twenty compounds (1-20), of which three (1-3) were new. However, compounds 2 and 3 were previously reported as synthetic alpha,beta-lactones. The compounds were characterized as (-)-3,4',7-trihydroxy-3'-methoxyflavan (1), (-)-5,6-dihydro-6-undecyl-2H-pyran-2-one (2), and (-)-5,6-dihydro-6-tridecyl-2H-pyran-2-one (3). Seventeen other known compounds were also isolated and identified as (-)-viridiflorol (4), hexacosanoic acid (5), beta-sitosterol (6), methyl 2,4-dihydroxy-6-methylbenzoate (methylorsellinate) (7), methyl 2,4-dihydroxy-3,6-dimethylbenzoate (8), (-)-4'-hydroxy-7-methoxyflavan (9), (-)-4',7-dihydroxyflavan (10), (-)-4',7-dihydroxy-3'-methoxyflavan (11), (+)-3,4',7-trihydroxyflavan (12), (-)-catechin (13), (-)-epicatechin (14), (-)-7-hydroxy-3',4'-methylenedioxyflavan (15), 2',3,4-trihydroxy-4'-methoxydihydrochalcone (16), 3',4',7-trihydroxyflavone (17), (+)-4'-hydroxy-7-methoxyflavanone (18), hexadecanoic acid (palmitic acid) (19) and 3,4-dihydroxybenzoic acid (20). The structures of the compounds were fully characterized by various physical methods (melting point, optical rotation), spectral (UV, IR, ID and 2D NMR) and mass spectrometric techniques. In vitro assay of compounds 2 and 3 demonstrated moderate cytotoxic activities against human prostate (PC-3), colon (HCT-116) and breast (MCF-7) cancer cells, while the chloroform and ethyl acetate fractions of H. superba were found to exhibit moderate AChE inhibitory activity (IC50 72 and 60 microg/mL).
    Matched MeSH terms: Antineoplastic Agents, Phytogenic/isolation & purification; Cholinesterase Inhibitors/isolation & purification; Lactones/isolation & purification*
  2. Lasekan A, Abu Bakar F, Hashim D
    Waste Manag, 2013 Mar;33(3):552-65.
    PMID: 22985619 DOI: 10.1016/j.wasman.2012.08.001
    By-products from different animal sources are currently being utilised for beneficial purposes. Chicken processing plants all over the world generate large amount of solid by-products in form of heads, legs, bones, viscera and feather. These wastes are often processed into livestock feed, fertilizers and pet foods or totally discarded. Inappropriate disposal of these wastes causes environmental pollution, diseases and loss of useful biological resources like protein, enzymes and lipids. Utilisation methods that make use of these biological components for producing value added products rather than the direct use of the actual waste material might be another viable option for dealing with these wastes. This line of thought has consequently led to researches on these wastes as sources of protein hydrolysates, enzymes and polyunsaturated fatty acids. Due to the multi-applications of protein hydrolysates in various branches of science and industry, and the large body of literature reporting the conversion of animal wastes to hydrolysates, a large section of this review was devoted to this subject. Thus, this review reports the known functional and bioactive properties of hydrolysates derived from chicken by-products as well their utilisation as source of peptone in microbiological media. Methods of producing these hydrolysates including their microbiological safety are discussed. Based on the few references available in the literature, the potential of some chicken by-product as sources of proteases and polyunsaturated fatty acids are pointed out along with some other future applications.
    Matched MeSH terms: Fatty Acids, Unsaturated/isolation & purification; Peptide Hydrolases/isolation & purification; Peptones/isolation & purification
  3. Reddy KR, Farhana NI, Salleh B
    J Food Sci, 2011 May;76(4):T99-104.
    PMID: 22417376 DOI: 10.1111/j.1750-3841.2011.02133.x
    Malaysian population widely consumes the cereal-based foods, oilseeds, nuts, and spices in their daily diet. Mycotoxigenic fungi are well known to invade food products under storage conditions and produce mycotoxins that have threat to human and animal health. Therefore, determining toxigenic fungi and aflatoxin B(1) (AFB1) in foods used for human consumption is of prime importance to develop suitable management strategies and to minimize risk. Ninety-five food products marketed in Penang, Malaysia were randomly collected from different supermarkets and were analyzed for presence of Aspergillus spp. by agar plate assay and AFB1 by enzyme-linked immunosorbent assay (ELISA). A. flavus was the dominant fungi in all foods followed by A. niger. Fifty-five A. flavus strains were tested for their ability to produce aflatoxins on rice grain substrate. Thirty-six (65.4%) strains out of 55 produced AFB1 ranging from 1700 to 4400 μg/kg and 17 strains (31%) produced AFB2 ranging from 620 to 1670 μg/kg. Natural occurrence of AFB1 could be detected in 72.6% food products ranging from 0.54 to 15.33 μg/kg with a mean of 1.95 μg/kg. Maximum AFB1 levels were detected in peanut products ranging from 1.47 to 15.33 μg/kg. AFB1 levels detected in all food products were below the Malaysian permissible limits (<35 μg/kg). Aspergillus spp. and AFB1 was not detected in any cookies tested. Although this survey was not comprehensive, it provides valuable information on aflatoxin levels in foods marketed in Malaysia.
    Matched MeSH terms: Aspergillus/isolation & purification*; Spores, Fungal/isolation & purification; Aflatoxin B1/isolation & purification*
  4. Sanagi MM, Abbas HH, Ibrahim WA, Aboul-Enien HY
    Food Chem, 2012 Jul 15;133(2):557-62.
    PMID: 25683433 DOI: 10.1016/j.foodchem.2012.01.036
    Dispersive liquid-liquid microextraction method based on solidification of floating organic droplet (DLLME-SFO) was developed for the analysis of triazines. As model compounds four selected triazine herbicides namely, simazine, atrazine, secbumeton and cyanazine were employed to estimate the extraction efficiency. The experimental conditions were comprehensively studied for the DLLME-SFO method. Under the use of 10 μL of 1-undecanol as extraction solvent, 100 μL of acetonitrile as disperser solvent and 5% (w/v) NaCl for 3 min the results demonstrated that the repeatability (RSD%) of the optimised DLLME-SFO method ranged from 0.03% to 5.1% and the linearity in the range of 0.01-100 ppb. Low limits of detection (0.037-0.008 ppb), and good enrichment factors (195-322) were obtained. The DLLME-SFO method applied in water and sugarcane samples showed excellent relative recoveries (95.7-116.9%) with RSDs <8.6% (n=3) for all samples.
    Matched MeSH terms: Herbicides/isolation & purification*; Triazines/isolation & purification*; Water Pollutants, Chemical/isolation & purification*
  5. Amid BT, Mirhosseini H
    Molecules, 2012 Sep 10;17(9):10875-92.
    PMID: 22964503 DOI: 10.3390/molecules170910875
    Natural biopolymers from plant sources contain many impurities (e.g., fat, protein, fiber, natural pigment and endogenous enzymes), therefore, an efficient purification process is recommended to minimize these impurities and consequently improve the functional properties of the biopolymer. The main objective of the present study was to investigate the effect of different purification techniques on the yield, protein content, solubility, water- and oil-holding capacity of a heteropolysaccharide-protein biopolymer obtained from durian seed. Four different purification methods using different chemicals and solvents (i.e., A (isopropanol and ethanol), B (isopropanol and acetone), C (saturated barium hydroxide), and D (Fehling solution)] to liberate the purified biopolymer from its crude form were compared. In most cases, the purification process significantly (p < 0.05) improved the physicochemical properties of heteropolysaccharide-protein biopolymer from durian fruit seed. The present work showed that the precipitation using isopropanol and acetone (Method B) resulted in the highest purification yield among all the tested purification techniques. The precipitation using saturated barium hydroxide (Method C) led to induce the highest solubility and relatively high capacity of water absorption. The current study reveals that the precipitation using Fehling solution (Method D) most efficiently eliminates the protein fraction, thus providing more pure biopolymer suitable for biological applications.
    Matched MeSH terms: Biopolymers/isolation & purification; Glycoproteins/isolation & purification; Plant Proteins/isolation & purification
  6. Hanafiah MA, Ngah WS, Zolkafly SH, Teong LC, Majid ZA
    J Environ Sci (China), 2012;24(2):261-8.
    PMID: 22655386
    The potential of base treated Shorea dasyphylla (BTSD) sawdust for Acid Blue 25 (AB 25) adsorption was investigated in a batch adsorption process. Various physiochemical parameters such as pH, stirring rate, dosage, concentration, contact time and temperature were studied. The adsorbent was characterized with Fourier transform infrared spectrophotometer, scanning electron microscope and Brunauer, Emmett and Teller analysis. The optimum conditions for AB 25 adsorption were pH 2, stirring rate 500 r/min, adsorbent dosage 0.10 g and contact time 60 min. The pseudo second-order model showed the best conformity to the kinetic data. The equilibrium adsorption of AB 25 was described by Freundlich and Langmuir, with the latter found to agree well with the isotherm model. The maximum monolayer adsorption capacity of BTSD was 24.39 mg/g at 300 K, estimated from the Langmuir model. Thermodynamic parameters such as Gibbs free energy, enthalpy and entropy were determined. It was found that AB 25 adsorption was spontaneous and exothermic.
    Matched MeSH terms: Anthraquinones/isolation & purification*; Coloring Agents/isolation & purification; Water Pollutants, Chemical/isolation & purification*
  7. Khoo HE, Azlan A, Ismail A, Abas F
    Molecules, 2012 Aug 14;17(8):9754-73.
    PMID: 22893021 DOI: 10.3390/molecules17089754
    Solid phase extraction (SPE) using Sep-Pak® cartridges is one of the techniques used for fractionation of antioxidant compounds in waste of dabai oil extraction (defatted dabai parts). The aim of this study was to determine the phenolic compounds and antioxidant capacity in crude extracts and several SPE fractions from methanolic extract of defatted dabai pulp and peel. Based on SPE, Sep-Pak® cyanopropyl and C₁₈ cartridges were used to fractionate the antioxidant-rich crude extracts into water and methanolic fractions. Analyzed using LC-MS, flavonoids, anthocyanins, saponin derivatives and other unknown antioxidative compounds were detected in the defatted dabai crude extracts and their SPE fractions. Anthocyanins were the major phenolic compounds identified in the defatted dabai peel and detected in most of the SPE fractions. Methanolic fractions of defatted dabai parts embraced higher total phenolics and antioxidant capacity than water fractions. This finding also revealed the crude extracts of defatted dabai peel have the most significant antioxidant properties compared to the methanolic and water fractions studied. The crude extract of defatted dabai parts remain as the most potent antioxidant as it contains mixture of flavonoids, anthocyanins and other potential antioxidants.
    Matched MeSH terms: Antioxidants/isolation & purification*; Phenols/isolation & purification; Plant Extracts/isolation & purification*
  8. Ngu H, Wong KK, Law PL
    Water Environ Res, 2012 Apr;84(4):299-304.
    PMID: 22834217
    A circular gravity-phase separator using coalescing medium with cross flow was developed to remove oil and suspended solids from wastewaters. Coalescence medium in the form of inclined plates promotes rising of oil droplets through coalescence and settling of solid particles through coagulation. It exhibits 22.67% higher removal of total suspended solids (TSS) compared to separators without coalescing medium. Moreover, it removed more than 70% of oil compared to conventional American Petroleum Institute separators, which exhibit an average of 33% oil removal. The flowrate required to attain an effluent oil concentration of 10 mg/L (Q(o10)) at different influent oil concentrations (C(io)) can be represented by Q(o10) x 10(-5) = -0.0012C(io) + 0.352. The flowrate required to attain an effluent TSS concentration of 50 mg/L (Q(ss50)) at different influent TSS concentrations (C(iss)) can be represented by Q(ss50) x 10(-5) = 1.0 x 10(6) C(iss)(-2.9576). The smallest removable solid particle size was 4.87 microm.
    Matched MeSH terms: Oils/isolation & purification*; Water Pollutants, Chemical/isolation & purification*; Particulate Matter/isolation & purification*
  9. Yahayu MA, Rahmani M, Hashim NM, Amin MA, Ee GC, Sukari MA, et al.
    Molecules, 2011 May 27;16(6):4401-7.
    PMID: 21623311 DOI: 10.3390/molecules16064401
    Extraction and chromatographic separation of the extracts of dried stem barks of Glycosmis macrantha lead to isolation of two new acridone alkaloids, macranthanine and 7-hydroxynoracronycine, and a known acridone, atalaphyllidine. The structures of these alkaloids were determined by detailed spectral analysis and also by comparison with reported data.
    Matched MeSH terms: Acridines/isolation & purification; Alkaloids/isolation & purification; Plant Extracts/isolation & purification
  10. Gunasegaran T, Rathinam X, Kasi M, Sathasivam K, Sreenivasan S, Subramaniam S
    Asian Pac J Trop Biomed, 2011 Aug;1(4):266-9.
    PMID: 23569772 DOI: 10.1016/S2221-1691(11)60040-3
    To isolate Salmonella from curry samples and to evaluate the drug sensitivity of the food-borne Salmonella and its susceptibility to specific plant extracts.
    Matched MeSH terms: Anti-Bacterial Agents/isolation & purification; Plant Extracts/isolation & purification; Salmonella/isolation & purification
  11. Lau LC, Lee KT, Mohamed AR
    J Hazard Mater, 2010 Nov 15;183(1-3):738-45.
    PMID: 20724075 DOI: 10.1016/j.jhazmat.2010.07.088
    In order to reduce the negative impact of coal utilization for energy generation, the pollutants present in the flue gas of coal combustion such as sulfur dioxide (SO(2)) and nitrogen oxide (NO) must be effectively removed before releasing to the atmosphere. Thus in this study, sorbent prepared from rice husk ash that is impregnated with copper is tested for simultaneous removal of SO(2) and NO from simulated flue gas. The effect of various sorbent preparation parameters; copper loading, RHA/CaO ratio, hydration period and NaOH concentration on the sorbent desulfurization/denitrification capacity was studied using Design-Expert Version 6.0.6 software. Specifically, Central Composite Design (CCD) coupled with Response Surface Method (RSM) was used. Significant individual parameters that affect the sorbent capacity are copper loading and NaOH concentration. Apart from that, interaction between the following parameters was also found to have significant effect; copper loading, RHA/CaO ratio and NaOH concentration. The optimum sorbent preparation condition for this study was found to be 3.06% CuO loading, RHA/CaO ratio of 1.41, 8.05 h of hydration period and NaOH concentration of 0.80 M. Sorbent characterization using SEM, XRD and surface area analysis were used to describe the effect of sorbent preparation parameters on the desulfurization/denitrification activity.
    Matched MeSH terms: Air Pollutants/isolation & purification*; Nitric Oxide/isolation & purification*; Sulfur Dioxide/isolation & purification*
  12. Ramasamy K, Lim SM, Abu Bakar H, Ismail N, Ismail MS, Ali MF, et al.
    Phytother Res, 2010 May;24(5):640-3.
    PMID: 19468989 DOI: 10.1002/ptr.2891
    Endophytes, which are receiving increasing attention, have been found to be potential sources of bioactive metabolites following the discovery of paclitaxel producing endophytic fungi. In the present study, a total of 348 endophytes were isolated from different parts of 24 Malaysian medicinal plants. Three selected endophytes (HAB10R12, HAB11R3 and HAB21F25) were investigated for their antimicrobial and cytotoxic activities. For antimicrobial activity, HAB10R12 and HAB11R3 were found to be most active against bacteria and fungi, respectively. Their antimicrobial effects were comparable to, if not better than, a number of current commercial antibacterial and antifungal agents. Both HAB10R12 and HAB21F25 were found to be potential anticancer drug candidates, having potent activity against MCF-7 and HCT116 cell lines and warrant further investigation.
    Matched MeSH terms: Anti-Bacterial Agents/isolation & purification*; Antifungal Agents/isolation & purification*; Antineoplastic Agents, Phytogenic/isolation & purification*
  13. Sim KM, Mak CN, Ho LP
    J Asian Nat Prod Res, 2009 Aug;11(8):757-60.
    PMID: 20183320 DOI: 10.1080/10286020903058933
    A new amide alkaloid, N-(3',4',5'-trimethoxy-cis-cinnamoyl)pyrrolidine (1), named sarmentomicine was isolated from the ethanol extract of the leaves of Malayan Piper sarmentosum, together with two known phenylpropanoids. Their structures were elucidated on the basis of spectroscopic analysis.
    Matched MeSH terms: Alkaloids/isolation & purification*; Amides/isolation & purification*; Pyrrolidines/isolation & purification*
  14. Kho YS, Vikineswary S, Abdullah N, Kuppusamy UR, Oh HI
    J Med Food, 2009 Feb;12(1):167-74.
    PMID: 19298211 DOI: 10.1089/jmf.2007.0568
    Auricularia auricula-judae is currently grown in Malaysia. In the present study, the methanolic extracts from fruit bodies (fresh, oven-dried, and freeze-dried) and mycelium of A. auricula-judae were evaluated for their antioxidant capacities based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and ferric reducing antioxidant power (FRAP) assay. The total phenolic content in the extracts were also measured. The extract of freeze-dried fruit bodies of A. auricula-judae had potent DPPH free radical scavenging activity with a 50% effective concentration of 2.87 mg/mL, whereas the FRAP value of A. auricula-judae mycelium was 5.22 micromol of FeSO(4).7H(2)O equivalents/g of mycelium sample. Further, a positive correlation (R(2) = 0.7668) between FRAP level of A. auricula-judae extracts and the total phenolic contents was observed. Thus the method of processing of fresh fruit bodies had an effect on the antioxidant potential of A. auricula-judae.
    Matched MeSH terms: Antioxidants/isolation & purification; Phenols/isolation & purification; Free Radical Scavengers/isolation & purification
  15. Mukhtar MR, Aziz AN, Thomas NF, Hadi AH, Litaudon M, Awang K
    Molecules, 2009;14(3):1227-33.
    PMID: 19325519 DOI: 10.3390/molecules14031227
    The stem bark of Phoebe grandis afforded one new oxoproaporphine; (-)-grandine A (1), along with six known isoquinoline alkaloids: (-)-8,9-dihydrolinearisine (2), boldine, norboldine, lauformine, scortechiniine A and scortechiniine B. In addition to that of the new compound, complete 1H- and 13C-NMR data of the tetrahydroproaporphine (-)-8,9-dihydrolinearisine (2) is also reported. The alkaloids' structures were elucidated primarily by means of high field 1D- and 2D-NMR and HRMS spectral data.
    Matched MeSH terms: Alkaloids/isolation & purification; Aporphines/isolation & purification; Isoquinolines/isolation & purification
  16. Chong FC, Tan WS, Biak DR, Ling TC, Tey BT
    J Chromatogr A, 2010 Feb 19;1217(8):1293-7.
    PMID: 20044094 DOI: 10.1016/j.chroma.2009.12.039
    A direct recovery of recombinant nucleocapsid protein of Nipah virus (NCp-NiV) from crude Escherichia coli (E. coli) homogenate was developed successfully using a hydrophobic interaction expanded bed adsorption chromatography (HI-EBAC). The nucleic acids co-released with the recombinant protein have increased the viscosity of the E. coli homogenate, thus affected the axial mixing in the EBAC column. Hence, DNase was added to reduce the viscosity of feedstock prior to its loading into the EBAC column packed with the hydrophobic interaction chromatography (HIC) adsorbent. The addition of glycerol to the washing buffer has reduced the volume of washing buffer applied, and thus reduced the loss of the NCp-NiV during the washing stage. The influences of flow velocity, degree of bed expansion and viscosity of mobile phase on the adsorption efficiency of HI-EBAC were studied. The dynamic binding capacity at 10% breakthrough of 3.2mg/g adsorbent was achieved at a linear flow velocity of 178 cm/h, bed expansion of two and feedstock viscosity of 3.4 mPas. The adsorbed NCp-NiV was eluted with the buffer containing a step gradient of salt concentration. The purification of hydrophobic NCp-NiV using the HI-EBAC column has recovered 80% of NCp-NiV from unclarified E. coli homogenate with a purification factor of 12.5.
    Matched MeSH terms: Recombinant Proteins/isolation & purification*; Nucleocapsid Proteins/isolation & purification*; Nipah Virus/isolation & purification*
  17. Hameed BH, Tan IA, Ahmad AL
    J Hazard Mater, 2009 May 30;164(2-3):1316-24.
    PMID: 18977086 DOI: 10.1016/j.jhazmat.2008.09.042
    The effects of three preparation variables: CO(2) activation temperature, CO(2) activation time and KOH:char impregnation ratio (IR) on the 2,4,6-trichlorophenol (2,4,6-TCP) uptake and carbon yield of the activated carbon prepared from oil palm empty fruit bunch (EFB) were investigated. Based on the central composite design, two quadratic models were developed to correlate the three preparation variables to the two responses. The activated carbon preparation conditions were optimized using response surface methodology by maximizing both the 2,4,6-TCP uptake and activated carbon yield within the ranges studied. The optimum conditions for preparing activated carbon from EFB for adsorption of 2,4,6-TCP were found as follows: CO(2) activation temperature of 814 degrees C, CO(2) activation time of 1.9h and IR of 2.8, which resulted in 168.89 mg/g of 2,4,6-TCP uptake and 17.96% of activated carbon yield. The experimental results obtained agreed satisfactorily with the model predictions. The activated carbon prepared under optimum conditions was mesoporous with BET surface area of 1141 m(2)/g, total pore volume of 0.6 cm(3)/g and average pore diameter of 2.5 nm. The surface morphology and functional groups of the activated carbon were respectively determined from the scanning electron microscopy and Fourier transform infrared analysis.
    Matched MeSH terms: Chlorophenols/isolation & purification*; Environmental Pollutants/isolation & purification; Mutagens/isolation & purification
  18. Hameed BH
    J Hazard Mater, 2009 Jul 15;166(1):233-8.
    PMID: 19111987 DOI: 10.1016/j.jhazmat.2008.11.019
    The aim of the present work was to investigate the feasibility of grass waste (GW) for methylene blue (MB) adsorption. The adsorption of MB on GW material was studied as a function of GW dose (0.05-1.20 g), solution pH 3-10, contact time and initial concentration (70-380 mg/L). The influence of these parameters on the adsorption capacity was studied using the batch process. The experimental data were analyzed by the Langmuir and Freundlich isotherms. The adsorption isotherm was found to follow the Langmuir model. The monolayer adsorption capacity was found to be 457.640 mg/g. The kinetic data were fitted to the pseudo-first-order and pseudo-second-order models, and were found to follow closely the pseudo-second-order kinetic model. The results revealed that GW adsorbent is potentially low-cost adsorbent for adsorption of MB.
    Matched MeSH terms: Coloring Agents/isolation & purification; Methylene Blue/isolation & purification*; Water Pollutants, Chemical/isolation & purification*
  19. Tan IA, Ahmad AL, Hameed BH
    J Hazard Mater, 2009 May 30;164(2-3):473-82.
    PMID: 18818013 DOI: 10.1016/j.jhazmat.2008.08.025
    The adsorption characteristics of 2,4,6-trichlorophenol (TCP) on activated carbon prepared from oil palm empty fruit bunch (EFB) were evaluated. The effects of TCP initial concentration, agitation time, solution pH and temperature on TCP adsorption were investigated. TCP adsorption uptake was found to increase with increase in initial concentration, agitation time and solution temperature whereas adsorption of TCP was more favourable at acidic pH. The adsorption equilibrium data were best represented by the Freundlich and Redlich-Peterson isotherms. The adsorption kinetics was found to follow the pseudo-second-order kinetic model. The mechanism of the adsorption process was determined from the intraparticle diffusion model. Boyd plot revealed that the adsorption of TCP on the activated carbon was mainly governed by particle diffusion. Thermodynamic parameters such as standard enthalpy (DeltaH degrees ), standard entropy (DeltaS degrees ), standard free energy (DeltaG degrees ) and activation energy were determined. The regeneration efficiency of the spent activated carbon was high, with TCP desorption of 99.6%.
    Matched MeSH terms: Chlorophenols/isolation & purification*; Mutagens/isolation & purification; Water Pollutants, Chemical/isolation & purification*
  20. Yusof AM, Malek NA
    J Hazard Mater, 2009 Mar 15;162(2-3):1019-24.
    PMID: 18632204 DOI: 10.1016/j.jhazmat.2008.05.134
    The synthesized zeolite NaY from rice husk ash (RHA) and the commercial zeolite NaY both modified with surfactants in amounts equal to 50%, 100% and 200% of their external cation exchange capacity (ECEC) were used to remove chromate and arsenate anions from aqueous solutions. While the unmodified zeolite Y had little or no affinity for the Cr(VI) and As(V) anionic species, the surfactant-modified zeolite Y (SMZY) showed significant ability to remove of these anions from the aqueous solutions. The highest chromates and arsenates adsorption efficiency was observed from solutions of pH values 3 and 8, respectively because of the dominance of the univalent species of both anions. The adsorption equilibrium data were best fitted with the Langmuir isotherm model with the highest removal capacities observed for the SMZY initially prepared considering the hexadecyltrimethyl ammonium (HDTMA) amount equal to the 100% of the ECEC of zeolite Y. Synthesized SMZY remove Cr(VI) and As(V) more than the corresponding commercial one due to its lower silica to alumina ratio. Thus, the HDTMA-covered modified zeolite Y synthesized using RHA can be used to remove Cr(VI) and As(V) from water.
    Matched MeSH terms: Arsenic/isolation & purification*; Chromium/isolation & purification*; Water Pollutants, Chemical/isolation & purification*
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