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  1. Fulltext Acaricidal activity of Cymbopogon citratus and Azadirachta indica against house dust mites
    Hanifah AL, Awang SH, Ho TM, Abidin SZ, Omar MH
    Asian Pac J Trop Biomed, 2011 Oct;1(5):365-9.
    PMID: 23569794 DOI: 10.1016/S2221-1691(11)60081-6
    To examine the acaricidal effects of the essential oil of Cymbopogon citratus leaf extract (lemongrass) and ethanolic Azadirachta indica leaf extract (neem) against house dust mites Dermatophagoides farinae (D. farinae) and Dermatophagoides pteronyssinus (D. pteronyssinus).
    Matched MeSH terms: Plant Extracts/chemistry; Azadirachta/chemistry*; Cymbopogon/chemistry*; Acaricides/chemistry
  2. Fulltext Use of a reflectance spectroscopy accessory for optical characterization of ZnO-Bi(2)O(3)-TiO(2) ceramics
    Ghazali MS, Zakaria A, Rizwan Z, Kamari HM, Hashim M, Zaid MH, et al.
    Int J Mol Sci, 2011;12(3):1496-504.
    PMID: 21673903 DOI: 10.3390/ijms12031496
    The optical band-gap energy (E(g)) is an important feature of semiconductors which determines their applications in optoelectronics. Therefore, it is necessary to investigate the electronic states of ceramic ZnO and the effect of doped impurities under different processing conditions. E(g) of the ceramic ZnO + xBi(2)O(3) + xTiO(2), where x = 0.5 mol%, was determined using a UV-Vis spectrophotometer attached to a Reflectance Spectroscopy Accessory for powdered samples. The samples was prepared using the solid-state route and sintered at temperatures from 1140 to 1260 °C for 45 and 90 minutes. E(g) was observed to decrease with an increase of sintering temperature. XRD analysis indicated hexagonal ZnO and few small peaks of intergranular layers of secondary phases. The relative density of the sintered ceramics decreased and the average grain size increased with the increase of sintering temperature.
    Matched MeSH terms: Bismuth/chemistry*; Ceramics/chemistry*; Titanium/chemistry*; Zinc Oxide/chemistry*
  3. Response surface methodology analysis of the photocatalytic removal of Methylene Blue using bismuth vanadate prepared via polyol route
    Abdullah AH, Moey HJ, Yusof NA
    J Environ Sci (China), 2012;24(9):1694-701.
    PMID: 23520879
    Visible-light driven photocatalyst bismuth vanadate (BiVO4) photocatalyst was synthesized by the polyol route using ethylene glycol. The precipitate was washed, dried and calcined at 450 degrees C for 3 hr. The sample was characterized by X-ray diffractometry (XRD), field emission scanning electron microscopy (FE-SEM), zeta potential, surface area (BET method) and band gap energy via diffuse reflectance spectroscopy (DRS). The synthesized BiVO4 has a monoclinic phase with a surface area of 4.3 m2/g and a band gap energy of 2.46 eV. A majority of the particles were in the range of 90-130 nm as obtained from the particle size distribution histrogram. The efficiency of the sample as a visible-light driven photocatalyst was examined by photodegrading Methylene Blue (MB). The effects of some operational photodegradation parameters such as mass loading, initial dye concentration and pH were also examined. Experimental design methodology was applied by response surface modeling and optimization of the removal of MB. The multivariate experimental design was employed to develop a quadratic model as a functional relationship between the percentage removal of MB and three experimental factors (BiVO4 loading, MB initial concentration and pH). The percentage removal of MB approached 67.21% under optimized conditions. In addition, a satisfactory goodness-of-fit was achieved between the,predictive and the experimental results.
    Matched MeSH terms: Bismuth/chemistry*; Methylene Blue/chemistry*; Polymers/chemistry*; Vanadates/chemistry*
  4. Enhanced growth of lactobacilli and bioconversion of isoflavones in biotin-supplemented soymilk upon ultrasound-treatment
    Ewe JA, Wan Abdullah WN, Bhat R, Karim AA, Liong MT
    Ultrason Sonochem, 2012 Jan;19(1):160-73.
    PMID: 21775184 DOI: 10.1016/j.ultsonch.2011.06.013
    This study aimed at utilizing ultrasound treatment to further enhance the growth of lactobacilli and their isoflavone bioconversion activities in biotin-supplemented soymilk. Strains of lactobacilli (Lactobacillus acidophilus BT 1088, L. fermentum BT 8219, L. acidophilus FTDC 8633, L. gasseri FTDC 8131) were treated with ultrasound (30 kHz, 100 W) at different amplitudes (20%, 60% and 100%) for 60, 120 and 180 s prior to inoculation and fermentation in biotin-soymilk. The treatment affected the fatty acids chain of the cellular membrane lipid bilayer, as shown by an increased lipid peroxidation (P<0.05). This led to increased membrane fluidity and subsequently, membrane permeability (P<0.05). The permeabilized cellular membranes had facilitated nutrient internalization and subsequent growth enhancement (P<0.05). Higher amplitudes and longer durations of the treatment promoted growth of lactobacilli in soymilk, with viable counts exceeding 9 log CFU/mL. The intracellular and extracellular β-glucosidase specific activities of lactobacilli were also enhanced (P<0.05) upon ultrasound treatment, leading to increased bioconversion of isoflavones in soymilk, particularly genistin and malonyl genistin to genistein. Results from this study show that ultrasound treatment on lactobacilli cells promotes (P<0.05) the β-glucosidase activity of cells for the benefit of enhanced (P<0.05) isoflavone glucosides bioconversion to bioactive aglycones in soymilk.
    Matched MeSH terms: Biotin/chemistry; Isoflavones/chemistry; Lactobacillus/chemistry; Soy Milk/chemistry
  5. Fulltext Effect of surfactant and surfactant blends on pseudoternary phase diagram behavior of newly synthesized palm kernel oil esters
    Mahdi ES, Sakeena MH, Abdulkarim MF, Abdullah GZ, Sattar MA, Noor AM
    Drug Des Devel Ther, 2011;5:311-23.
    PMID: 21792294 DOI: 10.2147/DDDT.S15698
    The purpose of this study was to select appropriate surfactants or blends of surfactants to study the ternary phase diagram behavior of newly introduced palm kernel oil esters.
    Matched MeSH terms: Hexoses/chemistry*; Plant Oils/chemistry*; Polysorbates/chemistry*; Surface-Active Agents/chemistry*
  6. Selective binding of imidazolium cations in building multi-component layers
    Ling I, Alias Y, Sobolev AN, Byrne LT, Raston CL
    Chemistry, 2010 Jun 18;16(23):6973-82.
    PMID: 20455217 DOI: 10.1002/chem.200903320
    Addition of 1-alkyl-3-methylimidazolium (C(n)-mim) cations 3-5 to a mixture of bis-phosphonium cation 2 and sodium p-sulfonatocalix[4]arene (1) in the presence of lanthanide ions results in the selective binding of an imidazolium cation into the cavity of the calixarene. The result is a multi-layered solid material with an inherently flexible interplay of the components. Incorporating ethyl-, n-butyl- or n-hexyl-mim cations into the multi-layers results in significant perturbation of the structure, the most striking effect is the tilting of the plane of the bowl-shaped calixarene relative to the plane of the multi-layer, with tilt angles of 7.2, 28.9 and 65.5 degrees , respectively. The lanthanide ions facilitate complexation, but are not incorporated into the structures and, in all cases, the calixarene takes on a 5- charge, with one of the lower-rim phenolic groups deprotonated. ROESY NMR experiments and other (1)H NMR spectroscopy studies establish the formation of 1:1 supermolecules of C(n)-mim and calixarene, regardless of the ratio of the two components, and indicate that the supermolecules undergo rapid exchange on the NMR spectroscopy timescale.
    Matched MeSH terms: Cations/chemistry*; Imidazoles/chemistry*; Organophosphorus Compounds/chemistry; Calixarenes/chemistry*
  7. Biaxial flexural strength of Turkom-Cera core compared to two other all-ceramic systems
    Al-Makramani BM, Razak AA, Abu-Hassan MI
    J Appl Oral Sci, 2010 Dec;18(6):607-12.
    PMID: 21308292
    Advances in all-ceramic systems have established predictable means of providing metal-free aesthetic and biocompatible materials. These materials must have sufficient strength to be a practical treatment alternative for the fabrication of crowns and fixed partial dentures.

    OBJECTIVES: The aim of this study was to compare the biaxial flexural strength of three core ceramic materials.

    MATERIAL AND METHODS: Three groups of 10 disc-shaped specimens (16 mm diameter x 1.2 mm thickness - in accordance with ISO-6872, 1995) were made from the following ceramic materials: Turkom-Cera Fused Alumina [(Turkom-Ceramic (M) Sdn Bhd, Puchong, Selangor, Malaysia)], In-Ceram (Vita Zahnfabrik, Bad Säckingen, Baden-Württemberg, Germany) and Vitadur-N (Vita Zahnfabrik, Bad Säckingen, Baden-Württemberg, Germany), which were sintered according to the manufacturer's recommendations. The specimens were subjected to biaxial flexural strength test in an universal testing machine at a crosshead speed of 0.5 mm/min. The definitive fracture load was recorded for each specimen and the biaxial flexural strength was calculated from an equation in accordance with ISO-6872.

    RESULTS: The mean biaxial flexural strength values were: Turkom-Cera: 506.8 ± 87.01 MPa, In-Ceram: 347.4 ± 28.83 MPa and Vitadur-N: 128.7 ± 12.72 MPa. The results were analyzed by the Levene's test and Dunnett's T3 post-hoc test (SPSS software V11.5.0 for Windows, SPSS, Chicago, IL, USA ) at a preset significance level of 5% because of unequal group variances (P<0.001). There was statistically significant difference between the three core ceramics (P<0.05). Turkom-Cera showed the highest biaxial flexural strength, followed by In-Ceram and Vitadur-N.

    CONCLUSIONS: Turkom-Cera core had significantly higher flexural strength than In-Ceram and Vitadur-N ceramic core materials.

    Matched MeSH terms: Aluminum Oxide/chemistry*; Ceramics/chemistry*; Dental Materials/chemistry*; Dental Porcelain/chemistry*
  8. Two new polymorphs of 2,6-diaminopyrimidin-4(3H)-one monohydrate
    Suleiman Gwaram N, Khaledi H, Ali HM, Olmstead MM
    Acta Crystallogr C, 2011 Jan;67(Pt 1):o6-9.
    PMID: 21206084 DOI: 10.1107/S0108270110046317
    The title compound, C(4)H(6)N(4)O·H(2)O, crystallized simultaneously as a triclinic and a monoclinic polymorph from an aqueous solution of 2,4-diaminopyrimidin-6-ol. Previously, an orthorhombic polymorph was isolated under the same experimental conditions. The molecular geometric parameters in the two present polymorphs and the previously reported orthorhombic polymorph are similar, but the structures differ in the details of their crystal packing. In the triclinic system, the diaminopyrimidinone molecules are connected to one another via N-H···O and N-H···N hydrogen bonding to form infinite chains in the [011] direction. The chains are further hydrogen bonded to the water molecules, resulting in a three-dimensional network. In the monoclinic system, the diaminopyrimidinone molecules are hydrogen bonded together into two-dimensional networks parallel to the bc plane. The water molecules link the planes to form a three-dimensional polymeric structure.
    Matched MeSH terms: Ions/chemistry*; Polymers/chemistry; Pyridines/chemistry*; Water/chemistry*
  9. Transesterification of palm oil to methyl ester on activated carbon supported calcium oxide catalyst
    Wan Z, Hameed BH
    Bioresour Technol, 2011 Feb;102(3):2659-64.
    PMID: 21109428 DOI: 10.1016/j.biortech.2010.10.119
    In this study, methyl ester (ME) was produced by transesterification of palm oil (CPO) (cooking grade) using activated carbon supported calcium oxide as a solid base catalyst (CaO/AC). Response surface methodology (RSM) based on central composite design (CCD) was used to optimize the effect of reaction time, molar ratio of methanol to oil, reaction temperature and catalyst amount on the transesterification process. The optimum condition for CPO transesterification to methyl ester was obtained at 5.5 wt.% catalyst amount, 190°C temperature, 15:1 methanol to oil molar ratio and 1 h 21 min reaction time. At the optimum condition, the ME content was 80.98%, which is well within the predicted value of the model. Catalyst regeneration studies indicate that the catalyst performance is sustained after two cycles.
    Matched MeSH terms: Charcoal/chemistry*; Oxides/chemistry*; Plant Oils/chemistry*; Calcium Compounds/chemistry*
  10. Fulltext Synthesis of new azo compounds based on N-(4-hydroxypheneyl)maleimide and N-(4-methylpheneyl)maleimide
    Mohammed IA, Mustapha A
    Molecules, 2010;15(10):7498-509.
    PMID: 20975631 DOI: 10.3390/molecules15107498
    Maleic anhydride was reacted with p-aminophenol and p-toluidine in the presence of di-phosphorus pentoxide (P₂O₅) as a catalyst to produce two compounds: N-(4-hydroxy-phenyl)maleimide (I) and N-(4-methylphenyl)maleimide (II). The new azo compounds I(a-c) and II(a-c) were prepared by the reaction of I and II with three different aromatic amines, namely aniline, p-aminophenol and p-toluidine. The structures of these compounds were confirmed by CHN, FT-IR, ¹H-NMR, ¹³C-NMR, mass spectrum and UV/Vis spectroscopy.
    Matched MeSH terms: Aminophenols/chemistry; Azo Compounds/chemistry; Maleimides/chemistry*; Toluidines/chemistry
  11. Fulltext Boronate derivatives of functionally diverse catechols: stability studies
    Ketuly KA, Hadi AH
    Molecules, 2010 Apr;15(4):2347-56.
    PMID: 20428047 DOI: 10.3390/molecules15042347
    Benzeneboronate of catecholic carboxyl methyl esters, N-acetyldopamine, coumarin and catechol estrogens were prepared as crystalline derivatives in high yield. Related catechol compounds with extra polar functional group(s) (OH, NH2) do not form or only partially form unstable cyclic boronate derivatives.
    Matched MeSH terms: Boronic Acids/chemistry*; Estrogens, Catechol/chemistry*; Coumarins/chemistry*; Dopamine/chemistry
  12. Utilization of waste crab shell (Scylla serrata) as a catalyst in palm olein transesterification
    Boey PL, Maniam GP, Hamid SA
    J Oleo Sci, 2009;58(10):499-502.
    PMID: 19745576
    Aquaculture activity has increased the population of crab, hence increasing the generation of related wastes, particularly the shell. In addition, the number of molting process in crabs compounds further the amount of waste shell generated. As such, in the present work, the application of the waste crab shell as a source of CaO in transesterification of palm olein to biodiesel (methyl ester) was investigated. Preliminary XRD results revealed that thermally activated crab shell contains mainly CaO. Parametric study has been investigated and optimal conditions were found to be methanol/oil mass ratio, 0.5:1; catalyst amount, 4 wt. %; and reaction temperature, 338 K. As compared to laboratory CaO, the catalyst from waste crab shell performs well, thus creating another low-cost catalyst source for producing biodiesel as well as adding value to the waste crab shell. Reusability of crab shell CaO has also been studied and the outcome confirmed that the catalyst is capable to be reutilized up to 11 times, without any major deterioration.
    Matched MeSH terms: Brachyura/chemistry*; Oxides/chemistry; Plant Oils/chemistry*; Calcium Compounds/chemistry
  13. Physicochemical and functional properties of ozone-oxidized starch
    Chan HT, Bhat R, Karim AA
    J Agric Food Chem, 2009 Jul 8;57(13):5965-70.
    PMID: 19489606 DOI: 10.1021/jf9008789
    The effects of oxidation by ozone gas on some physicochemical and functional properties of starch (corn, sago, and tapioca) were investigated. Starch in dry powder form was exposed to ozone for 10 min at different ozone generation times (OGTs). Carboxyl and carbonyl contents increased markedly in all starches with increasing OGTs. Oxidation significantly decreased the swelling power of oxidized sago and tapioca starches but increased that of oxidized corn starch. The solubility of tapioca starch decreased and sago starch increased after oxidation. However, there was an insignificant changed in the solubility of oxidized corn starch. Intrinsic viscosity [eta] of all oxidized starches decreased significantly, except for tapioca starch oxidized at 5 min OGT. Pasting properties of the oxidized starches followed different trends as OGTs increased. These results show that under similar conditions of ozone treatment, the extent of starch oxidation varies among different types of starch.
    Matched MeSH terms: Manihot/chemistry; Zea mays/chemistry; Ozone/chemistry*; Starch/chemistry*
  14. A novel hydrothermal process to produce hydroxyapatite powders
    Sopyan I, Rosli A, Raihana MF
    Med J Malaysia, 2008 Jul;63 Suppl A:81-2.
    PMID: 19024994
    A novel hydrothermal process has been developed various hydroxyapatite(HA) powder. The HA powder was investigated in different calcination temperatures over the range of 200 degrees C-800 degrees C. TG/DTA and XRD analysis revealed that at temperatures of 700-800 degrees C the decomposition processes and phase changes took place. It is due to the appearance of TCP phase substituting the HA phase. FESEM observation showed that the produced hydroxyapatite powder was extraordinarily fine with nanosize primary particles and almost evenly spherical in shaped. Its high purity proved that the powder fulfills medical requirement.
    Matched MeSH terms: Powders/chemistry; Durapatite/chemistry*; Bone Substitutes/chemistry; Coated Materials, Biocompatible/chemistry
  15. New phenantrene alkaloids from Cryptocarya crassinervia
    Awang K, Hadi AH, Saidi N, Mukhtar MR, Morita H, Litaudon M
    Fitoterapia, 2008 Jun;79(4):308-10.
    PMID: 18313862 DOI: 10.1016/j.fitote.2007.11.025
    The bark of Cryptocarya crassinervia provided two new phenantrene alkaloids, 2-hydroxyatherosperminine (1) and N-demethyl-2-methoxyatherosperminine (2).
    Matched MeSH terms: Alkaloids/chemistry*; Antineoplastic Agents, Phytogenic/chemistry; Phenanthrenes/chemistry*; Cryptocarya/chemistry*
  16. Use of microwave in processing of drug delivery systems
    Wong TW
    Curr Drug Deliv, 2008 Apr;5(2):77-84.
    PMID: 18393808
    Microwave has received a widespread application in pharmaceuticals and food processing, microbial sterilization, biomedical therapy, scientific and biomedical analysis, as well as, drug synthesis. This paper reviews the basis of application of microwave to prepare pharmaceutical dosage forms such as agglomerates, gel beads, microspheres, nanomatrix, solid dispersion, tablets and film coat. The microwave could induce drying, polymeric crosslinkages as well as drug-polymer interaction, and modify the structure of drug crystallites via its effects of heating and/or electromagnetic field on the dosage forms. The use of microwave opens a new approach to control the physicochemical properties and drug delivery profiles of pharmaceutical dosage forms without the need for excessive heat, lengthy process or toxic reactants. Alternatively, the microwave can be utilized to process excipients prior to their use in the formulation of drug delivery systems. The intended release characteristics of drugs in dosage forms can be met through modifying the physicochemical properties of excipients using the microwave.
    Matched MeSH terms: Chemistry, Pharmaceutical/methods; Pharmaceutical Preparations/chemistry*; Excipients/chemistry
  17. Degradation of malachite green in aqueous solution by Fenton process
    Hameed BH, Lee TW
    J Hazard Mater, 2009 May 30;164(2-3):468-72.
    PMID: 18804913 DOI: 10.1016/j.jhazmat.2008.08.018
    In this study, advanced oxidation process utilizing Fenton's reagent was investigated for degradation of malachite green (MG). The effects of different reaction parameters such as the initial MG concentration, initial pH, the initial hydrogen peroxide concentration, the initial ferrous concentration and the reaction temperature on the oxidative degradation of MG have been investigated. The optimal reacting conditions were experimentally found to be pH 3.40, initial hydrogen peroxide concentration=0.50mM and initial ferrous concentration=0.10mM for initial MG concentration of 20mg/L at 30 degrees C. Under optimal conditions, 99.25% degradation efficiency of dye in aqueous solution was achieved after 60 min of reaction.
    Matched MeSH terms: Hydrogen Peroxide/chemistry*; Iron/chemistry*; Rosaniline Dyes/chemistry*; Water Pollutants, Chemical/chemistry
  18. Bisindole alkaloids
    Kam TS, Choo YM
    Alkaloids Chem Biol, 2006;63:181-337.
    PMID: 17133716
    Matched MeSH terms: Chemistry, Organic/methods; Plants/chemistry; Indole Alkaloids/chemistry*
  19. Effect of temperature and salt concentration on rheological behavior of whey protein isolate-starch mixed dispersions
    Ravindra P, Chan ES, Reddy KU
    Int J Food Sci Nutr, 2007 Nov;58(7):542-7.
    PMID: 17852467
    Extensive studies have been carried out on the effect of temperature and salt concentration on the theological behavior of whey proteins and different starches individually, but not on mixed dispersions of whey protein isolates and starches. In the present studies, the rheological behavior of cross-linked waxy maize starch and whey protein isolate mixed dispersions during heating at 60-85 degrees C was investigated. Further, the effect of CaCl2 (25-100 mM ionic strengths) on the gelatinization of these dispersions was determined. It was found that at a 2:3 ratio and a 3:2 ratio of cross-linked waxy maize starch to whey protein isolate mixed gels form a compatible networkmM concentration the solution viscosity was higher.
    Matched MeSH terms: Gels/chemistry*; Milk Proteins/chemistry*; Sodium Chloride/chemistry*; Starch/chemistry*
  20. Lumusidines A-D and villalstonidine F, macroline-macroline and macroline-pleiocarpamine bisindole alkaloids from Alstonia macrophylla
    Lim SH, Low YY, Subramaniam G, Abdullah Z, Thomas NF, Kam TS
    Phytochemistry, 2013 Mar;87:148-56.
    PMID: 23200029 DOI: 10.1016/j.phytochem.2012.11.005
    Lumusidines A-D, bisindole alkaloids of the macroline-macroline type, and one of the macroline-pleiocarpamine type, villalstonidine F, were isolated from the stem-bark extract of Alstonia macrophylla (Apocynaceae). The structures and absolute configurations of these alkaloids were established using NMR, MS, and X-ray diffraction analyses.
    Matched MeSH terms: Alkaloids/chemistry*; Plant Extracts/chemistry*; Indole Alkaloids/chemistry*; Alstonia/chemistry*
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