Displaying publications 161 - 180 of 10433 in total

Abstract:
Sort:
  1. Kamairudin N, Gani SS, Masoumi HR, Hashim P
    Molecules, 2014;19(10):16672-83.
    PMID: 25325152 DOI: 10.3390/molecules191016672
    The D-optimal mixture experimental design was employed to optimize the melting point of natural lipstick based on pitaya (Hylocereus polyrhizus) seed oil. The influence of the main lipstick components-pitaya seed oil (10%-25% w/w), virgin coconut oil (25%-45% w/w), beeswax (5%-25% w/w), candelilla wax (1%-5% w/w) and carnauba wax (1%-5% w/w)-were investigated with respect to the melting point properties of the lipstick formulation. The D-optimal mixture experimental design was applied to optimize the properties of lipstick by focusing on the melting point with respect to the above influencing components. The D-optimal mixture design analysis showed that the variation in the response (melting point) could be depicted as a quadratic function of the main components of the lipstick. The best combination of each significant factor determined by the D-optimal mixture design was established to be pitaya seed oil (25% w/w), virgin coconut oil (37% w/w), beeswax (17% w/w), candelilla wax (2% w/w) and carnauba wax (2% w/w). With respect to these factors, the 46.0 °C melting point property was observed experimentally, similar to the theoretical prediction of 46.5 °C. Carnauba wax is the most influential factor on this response (melting point) with its function being with respect to heat endurance. The quadratic polynomial model sufficiently fit the experimental data.
    Matched MeSH terms: Chemistry, Pharmaceutical; Cosmetics/chemistry*; Plant Oils/chemistry*; Seeds/chemistry*; Waxes/chemistry*; Cactaceae/chemistry*
  2. Ghasemzadeh A, Jaafar HZ
    ScientificWorldJournal, 2014;2014:523120.
    PMID: 25147852 DOI: 10.1155/2014/523120
    Response surface methodology was applied to optimization of the conditions for reflux extraction of Pandan (Pandanus amaryllifolius Roxb.) in order to achieve a high content of total flavonoids (TF), total phenolics (TP), and high antioxidant capacity (AC) in the extracts. Central composite experimental design with three factors and three levels was employed to consider the effects of the operation parameters, including the methanol concentration (MC, 40%-80%), extraction temperature (ET, 40-70°C), and liquid-to-solid ratio (LS ratio, 20-40 mL/g) on the properties of the extracts. Response surface plots showed that increasing these operation parameters induced the responses significantly. The TF content and AC could be maximized when the extraction conditions (MC, ET, and LS ratio) were 78.8%, 69.5°C, and 32.4 mL/g, respectively, whereas the TP content was optimal when these variables were 75.1%, 70°C, and 31.8 mL/g, respectively. Under these optimum conditions, the experimental TF and TP content and AC were 1.78, 6.601 mg/g DW, and 87.38%, respectively. The optimized model was validated by a comparison of the predicted and experimental values. The experimental values were found to be in agreement with the predicted values, indicating the suitability of the model for optimizing the conditions for the reflux extraction of Pandan.
    Matched MeSH terms: Antioxidants/chemistry*; Flavonoids/chemistry*; Phenols/chemistry*; Plant Extracts/chemistry*; Pandanaceae/chemistry*; Phytochemicals/chemistry
  3. Liau CP, Bin Ahmad M, Shameli K, Yunus WM, Ibrahim NA, Zainuddin N, et al.
    ScientificWorldJournal, 2014;2014:572726.
    PMID: 24600329 DOI: 10.1155/2014/572726
    Polyhydroxybutyrate (PHB)/polycaprolactone (PCL)/stearate Mg-Al layered double hydroxide (LDH) nanocomposites were prepared via solution casting intercalation method. Coprecipitation method was used to prepare the anionic clay Mg-Al LDH from nitrate salt solution. Modification of nitrate anions by stearate anions between the LDH layers via ion exchange reaction. FTIR spectra showed the presence of carboxylic acid (COOH) group which indicates that stearate anions were successfully intercalated into the Mg-Al LDH. The formation of nanocomposites only involves physical interaction as there are no new functional groups or new bonding formed. X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicated that the mixtures of nanocomposites are intercalated and exfoliated types. XRD results showed increasing of basal spacing from 8.66 to 32.97 Å in modified stearate Mg-Al LDH, and TEM results revealed that the stearate Mg-Al LDH layers are homogeneously distributed in the PHB/PCL polymer blends matrix. Enhancement in 300% elongation at break and 66% tensile strength in the presence of 1.0 wt % of the stearate Mg-Al LDH as compare with PHB/PCL blends. Scanning electron microscopy (SEM) proved that clay improves compatibility between polymer matrix and the best ratio 80PHB/20PCL/1stearate Mg-Al LDH surface is well dispersed and stretched before it breaks.
    Matched MeSH terms: Aluminum/chemistry; Hydroxybutyrates/chemistry*; Magnesium/chemistry; Polyesters/chemistry*; Stearic Acids/chemistry; Nanocomposites/chemistry*
  4. Ali Hassan SH, Abu Bakar MF
    ScientificWorldJournal, 2013;2013:278071.
    PMID: 24298210 DOI: 10.1155/2013/278071
    Cyphomandra betacea is one of the underutilized fruits which can be found in tropical and subtropical countries. This study was conducted to determine the antioxidant activity and phytochemical contents in different parts (i.e., flesh and peel) of the fruits. Antioxidants were analyzed using DPPH and ABTS free radical scavenging assays as well as FRAP assay. Anticholinesterase activity was determined using enzymatic assay using acetyl cholinesterase enzyme. For 80% methanol extract, the peel of the fruit displayed higher antioxidant activity in both FRAP and ABTS free radical scavenging assays while the flesh displayed higher antioxidant activity in the DPPH assay. Total phenolic and total flavonoid content were higher in the peel with the values of 4.89 ± 0.04 mg gallic acid equivalent (GAE)/g and 3.36 ± 0.01 mg rutin equivalent (RU)/g, respectively. Total anthocyanin and carotenoid content were higher in the flesh of the fruit with the values of 4.15 ± 0.04 mg/100 g and 25.13 ± 0.35 mg/100 g. The anticholinesterase was also higher in the peel of C. betacea. The same trends of phytochemicals, antioxidant, and anticholinesterase were also observed in the distilled water extracts. These findings suggested that C. betacea has a potential as natural antioxidant-rich nutraceutical products.
    Matched MeSH terms: Acetylcholinesterase/chemistry*; Cholinesterase Inhibitors/chemistry*; Fruit/chemistry*; Plant Extracts/chemistry*; Free Radical Scavengers/chemistry*; Solanum/chemistry*
  5. Mukhopadhyay S, Mohd AH, Sahu JN, Yusoff I, Sen GB
    J Environ Sci (China), 2013 Nov 01;25(11):2247-56.
    PMID: 24552053
    This study explores the possible application of a biodegradable plant based surfactant, obtained from Sapindus mukorossi, for washing low levels of arsenic (As) from an iron (Fe) rich soil. Natural association of As(V) with Fe(III) makes the process difficult. Soapnut solution was compared to anionic surfactant sodium dodecyl sulfate (SDS) in down-flow and a newly introduced suction mode for soil column washing. It was observed that soapnut attained up to 86% efficiency with respect to SDS in removing As. Full factorial design of experiment revealed a very good fit of data. The suction mode generated up to 83 kPa pressure inside column whilst down-flow mode generated a much higher pressure of 214 kPa, thus making the suction mode more efficient. Micellar solubilisation was found to be responsible for As desorption from the soil and it followed 1st order kinetics. Desorption rate coefficient of suction mode was found to be in the range of 0.005 to 0.01, much higher than down-flow mode values. Analysis of the FT-IR data suggested that the soapnut solution did not interact chemically with As, offering an option for reusing the surfactant. Soapnut can be considered as a soil washing agent for removing As even from soil with high Fe content.
    Matched MeSH terms: Arsenic/chemistry*; Oxidoreductases/chemistry*; Soil/chemistry*; Soil Pollutants/chemistry*; Surface-Active Agents/chemistry*; Sapindus/chemistry*
  6. Kong KW, Mat-Junit S, Ismail A, Aminudin N, Abdul-Aziz A
    Food Chem, 2014 Mar 1;146:85-93.
    PMID: 24176317 DOI: 10.1016/j.foodchem.2013.09.012
    The polyphenolic profiles and antioxidant activities of the water extracts of Barringtonia racemosa shoots (leaves and stems) were explored. Two methods, freeze drying and air drying, for preparation of the shoots, were also compared. Freeze drying was better as air drying caused 5-41% reduction of polyphenols. Three phenolic acids and three flavonoids were identified, using UHPLC. The descending order of polyphenols in the leaves and stems was gallic acid>ellagic acid>quercetin>protocatechuic acid>rutin>kaempferol. In vitro antioxidant analyses were performed using biological samples. In the LDL oxidation assay, B. racemosa leaf extract (IC50=73.0μg/ml) was better than stem extract (IC50=226μg/ml) at inhibiting the formation of TBARS and lipid hydroperoxides. Similar trends were observed for serum and haemoglobin oxidation. B. racemosa leaf extract was better than its stem extract in delaying the time required to oxidise haemoglobin to methaemoglobin. The high polyphenolic content of B. racemosa shoots could have contributed towards their antioxidative effects.
    Matched MeSH terms: Hemoglobins/chemistry*; Lipoproteins, LDL/chemistry*; Plant Extracts/chemistry*; Barringtonia/chemistry*; Serum/chemistry*; Polyphenols/chemistry*
  7. Lasekan O
    Molecules, 2013 Sep 25;18(10):11809-23.
    PMID: 24071987 DOI: 10.3390/molecules181011809
    The influence of human salivary enzymes on palm wines' odorant concentrations were investigated by the application of aroma extracts dilution analysis (AEDA) and by the calculation of odour activity values (OAVs), respectively. The odorants were quantified by means of stable isotope dilution assays (SIDA), and the degradation profiles of odorants by human saliva were also studied. Results revealed 46 odour-active compounds in the flavour dilution (FD) factor range of 4-256, and all were subsequently identified. Of the 46 odorants, 41 were identified in the Elaeis guineensis wine, 36 in Raphia hookeri wine and 29 in Borassus flabellifer wine. Among the odorants, the highest FD-factors were obtained from acetoin, 2-acetyl-1-pyrroline and 3-isobutyl-2-methoxypyrazine. Among the 13 potent odorants identified, five aroma compounds are reported here as important contributors to palm wine aroma, namely 3-isobutyl-2-methoxy-pyrazine, acetoin, 2-acetyl-1-pyrroline, 3-methylbutylacetate and ethyl hexanoate. Meanwhile, salivary enzymic degradation of odorants was more pronounced among the aldehydes, esters and thiols.
    Matched MeSH terms: Aldehydes/chemistry; Plant Extracts/chemistry*; Pyrazines/chemistry; Pyrroles/chemistry; Saliva/chemistry; Arecaceae/chemistry*
  8. Tabatabaee Amid B, Mirhosseini H
    Colloids Surf B Biointerfaces, 2014 Jan 1;113:107-14.
    PMID: 24060935 DOI: 10.1016/j.colsurfb.2013.08.042
    The present work was conducted to investigate the effect of purification and conjugation processes on functional properties of durian seed gum (DSG) used for stabilization of water in oil in water (W/O/W) emulsion. Whey protein isolate (WPI) was conjugated to durian seed gum through the covalent linkage. In order to prepare WPI-DSG conjugate, covalent linkage of whey protein isolate to durian seed gum was obtained by Maillard reaction induced by heating at 60 °C and 80% (±1%) relative humidity. SDS-polyacrylamide gel electrophoresis was used to test the formation of the covalent linkage between whey protein isolate and durian seed gum after conjugation process. In this study, W/O/W stabilized by WPI-conjugated DSG A showed the highest interface activity and lowest creaming layer among all prepared emulsions. This indicated that the partial conjugation of WPI to DSG significantly improved its functional characteristics in W/O/W emulsion. The addition of WPI-conjugated DSG to W/O/W emulsion increased the viscosity more than non-conjugated durian seed gum (or control). This might be due to possible increment of the molecular weight after linking the protein fraction to the structure of durian seed gum through the conjugation process.
    Matched MeSH terms: Emulsions/chemistry*; Milk Proteins/chemistry*; Seeds/chemistry*; Water/chemistry*; Barium Compounds/chemistry; Bombacaceae/chemistry*
  9. Chan KW, Khong NM, Iqbal S, Ismail M
    Int J Mol Sci, 2012;13(6):7496-507.
    PMID: 22837707 DOI: 10.3390/ijms13067496
    The present study was conducted to evaluate the antioxidant properties of wheat and rice flours under simulated gastrointestinal pH condition. After subjecting the wheat and rice flour slurries to simulated gastrointestinal pH condition, both slurries were centrifuged to obtain the crude phenolic extracts for further analyses. Extraction yield, total contents of phenolic and flavonoids were determined as such (untreated) and under simulated gastrointestinal pH condition (treated). 1,1-diphenyl-2-picrylhydrazyl radical (DPPH(•)) scavenging activity, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical cation (ABTS(•+)) scavenging activity, ferric reducing antioxidant power (FRAP), beta-carotene bleaching (BCB) and iron chelating activity assays were employed for the determination of antioxidant activity of the tested samples. In almost all of the assays performed, significant improvements in antioxidant properties (p < 0.05) were observed in both flours after treatment, suggesting that wheat and rice flours contain considerably heavy amounts of bound phenolics, and that their antioxidant properties might be improved under gastrointestinal digestive conditions.
    Matched MeSH terms: Antioxidants/chemistry*; Flavonoids/chemistry; Gastric Juice/chemistry*; Phenols/chemistry; Oryza/chemistry*; Triticum/chemistry*
  10. Hussein MZ, Rahman NS, Sarijo SH, Zainal Z
    Int J Mol Sci, 2012;13(6):7328-42.
    PMID: 22837696 DOI: 10.3390/ijms13067328
    Herbicides, namely 4-(2,4-dichlorophenoxy) butyrate (DPBA) and 2-(3-chlorophenoxy) propionate (CPPA), were intercalated simultaneously into the interlayers of zinc layered hydroxide (ZLH) by direct reaction of zinc oxide with both anions under aqueous environment to form a new nanohybrid containing both herbicides labeled as ZCDX. Successful intercalation of both anions simultaneously into the interlayer gallery space of ZLH was studied by PXRD, with basal spacing of 28.7 Å and supported by FTIR, TGA/DTG and UV-visible studies. Simultaneous release of both CPPA and DPBA anions into the release media was found to be governed by a pseudo second-order equation. The loading and percentage release of the DPBA is higher than the CPPA anion, which indicates that the DPBA anion was preferentially intercalated into and released from the ZLH interlayer galleries. This work shows that layered single metal hydroxide, particularly ZLH, is a suitable host for the controlled release formulation of two herbicides simultaneously.
    Matched MeSH terms: Delayed-Action Preparations/chemistry; Herbicides/chemistry*; Hydroxides/chemistry*; Zinc/chemistry; Zinc Compounds/chemistry*; Nanostructures/chemistry*
  11. Al-Amiery AA, Musa AY, Kadhum AA, Mohamad AB
    Molecules, 2011 Aug 10;16(8):6833-43.
    PMID: 21832973 DOI: 10.3390/molecules16086833
    New coumarin derivatives, namely 7-[(5-amino-1,3,4-thiadiazol-2-yl)methoxy]-2H-chromen-2-one, 5-[(2-oxo-2H-chromen-7-yloxy)methyl]-1,3,4-thiadiazol-2(3H)-one, 2-[2-(2-oxo-2H-chromen-7-yloxy)acetyl]-N-phenylhydrazinecarbothioamide, 7-[(5-(phenylamino)-1,3,4-thiadiazol-2-yl)methoxy]-2H-chromen-2-one and 7-[(5-mercapto-4-phenyl-4H-1,2,4-triazol-3-yl)methoxy]-2H-chromen-2-one were prepared starting from the natural compound umbelliferone. The newly synthesized compounds were characterized by elemental analysis and spectral studies (IR, ¹H-NMR and ¹³C-NMR).
    Matched MeSH terms: Acetates/chemistry; Chemistry, Pharmaceutical/methods*; Hydrocarbons, Brominated/chemistry; Semicarbazides/chemistry; Thiadiazoles/chemistry
  12. Rizwan Z, Zakaria A, Ghazali MS
    Int J Mol Sci, 2011;12(3):1625-32.
    PMID: 21673911 DOI: 10.3390/ijms12031625
    Photopyroelectric (PPE) spectroscopy is a nondestructive tool that is used to study the optical properties of the ceramics (ZnO + 0.4MnO(2) + 0.4Co(3)O(4) + xV(2)O(5)), x = 0-1 mol%. Wavelength of incident light, modulated at 10 Hz, was in the range of 300-800 nm. PPE spectrum with reference to the doping level and sintering temperature is discussed. Optical energy band-gap (E(g)) was 2.11 eV for 0.3 mol% V(2)O(5) at a sintering temperature of 1025 °C as determined from the plot (ρhυ)(2)versushυ. With a further increase in V(2)O(5), the value of E(g) was found to be 2.59 eV. Steepness factor 'σ(A)' and 'σ(B)', which characterize the slope of exponential optical absorption, is discussed with reference to the variation of E(g). XRD, SEM and EDAX are also used for characterization of the ceramic. For this ceramic, the maximum relative density and grain size was observed to be 91.8% and 9.5 μm, respectively.
    Matched MeSH terms: Ceramics/chemistry*; Cobalt/chemistry*; Oxides/chemistry*; Zinc Oxide/chemistry*; Manganese Compounds/chemistry*; Vanadium Compounds/chemistry*
  13. Abd Rahman NF, Basri M, Rahman MB, Rahman RN, Salleh AB
    Bioresour Technol, 2011 Feb;102(3):2168-76.
    PMID: 21050749 DOI: 10.1016/j.biortech.2010.10.034
    Engkabang fat esters were produced via alcoholysis reaction between Engkabang fat and oleyl alcohol, catalyzed by Lipozyme RM IM. The reaction was carried out in a 500 ml Stirred tank reactor using heptane and hexane as solvents. Response surface methodology (RSM) based on a four-factor-five-level Central composite design (CCD) was applied to evaluate the effects of synthesis parameters, namely temperature, substrate molar ratio (oleyl alcohol: Engkabang fat), enzyme amount and impeller speed. The optimum yields of 96.2% and 91.4% were obtained for heptane and hexane at the optimum temperature of 53.9°C, impeller speeds of 309.5 and 309.0 rpm, enzyme amounts of 4.82 and 5.65 g and substrate molar ratios of 2.94 and 3.39:1, respectively. The actual yields obtained compared well with the predicted values of 100.0% and 91.5%, respectively. Meanwhile, the properties of the esters show that they are suitable to be used as ingredient for cosmetic applications.
    Matched MeSH terms: Emulsions/chemistry*; Fats/chemistry*; Fatty Alcohols/chemistry*; Lipase/chemistry*; Plant Extracts/chemistry*; Dipterocarpaceae/chemistry*
  14. Tan TC, AlKarkhi AF, Easa AM
    Food Chem, 2012 Oct 15;134(4):2430-6.
    PMID: 23442706 DOI: 10.1016/j.foodchem.2012.04.049
    The addition of ribose to bovine or porcine gelatine solutions followed by heating at 95 °C yielded brown solutions with different pH, colour (CIE L(*) and b(*)) and absorbance (A(420*) values. These differences were used for gelatine powder identification, differentiation and quality control. Differentiation analysis of the Maillard reaction parameters was conducted using cluster analysis (CA) and confidence intervals (CI). The potential use of the method as a quality control procedure was evaluated by using statistical process control (SPC). CA revealed that the two types of gelatine could be classified into two different groups. CI (95% confidence) revealed that the absorbance and colour values could be used as indicators for differentiation between the two types of gelatine because the intervals between the Maillard reaction parameters of the samples were far apart. The methodology demonstrated good reproducibility because it behaved predictably based on the X¯-S charts generated from the SPC charts.
    Matched MeSH terms: Chemistry Techniques, Analytical/methods*; Gelatin/chemistry*; Powders/chemistry; Ribose/chemistry*; Skin/chemistry
  15. Zainuddin SY, Ahmad I, Kargarzadeh H, Abdullah I, Dufresne A
    Carbohydr Polym, 2013 Feb 15;92(2):2299-305.
    PMID: 23399291 DOI: 10.1016/j.carbpol.2012.11.106
    Biodegradable materials made from cassava starch and kenaf fibers were prepared using a solution casting method. Kenaf fibers were treated with NaOH, bleached with sodium chlorite and acetic buffer solution, and subsequently acid hydrolyzed to obtain cellulose nanocrystals (CNCs). Biocomposites in the form of films were prepared by mixing starch and glycerol/sorbitol with various filler compositions (0-10 wt%). X-ray diffraction revealed that fiber crystallinity increased after each stage of treatment. Morphological observations and size reductions of the extracted cellulose and CNCs were studied using field emission scanning electron microscopy and transmission electron microscopy. The effects of different treatments and filler contents of the biocomposites were evaluated through mechanical tests. Results showed that the tensile strengths and moduli of the biocomposites increased after each treatment and the optimum filler content was 6%.
    Matched MeSH terms: Manihot/chemistry*; Cellulose/chemistry; Plastics/chemistry; Starch/chemistry*; Hibiscus/chemistry*; Nanoparticles/chemistry
  16. Benhamou K, Kaddami H, Magnin A, Dufresne A, Ahmad A
    Carbohydr Polym, 2015 May 20;122:202-11.
    PMID: 25817660 DOI: 10.1016/j.carbpol.2014.12.081
    Novel bio-based polyurethane (PU) nanocomposites composed of cellulose nanofiller extracted from the rachis of date palm tree and polycaprolactone (PCL) diol based PU were prepared by casting/evaporation. Two types of nanofiber were used: cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs). The mechanical and thermal properties of the nanocomposite films were studied by DMA, DSC, and tensile tests and the morphology was investigated by SEM. Bionanocomposites presented good mechanical properties in comparison to neat PU. While comparing both nanofillers, the improvement in mechanical and thermal properties was more pronounced for the nanocomposites based on CNF which could be explained, not only by the higher aspect ratio of CNF, but also by their better dispersion in the PU matrix. Calculation of the solubility parameters of the nanofiller surface polymers and of the PU segments portend a better interfacial adhesion for CNF based nanocomposites compared to CNC.
    Matched MeSH terms: Cellulose/chemistry*; Polymers/chemistry*; Polyurethanes/chemistry*; Nanoparticles/chemistry*; Nanocomposites/chemistry*; Nanofibers/chemistry*
  17. Aziz NA, Latip AFA, Peng LC, Latif NHA, Brosse N, Hashim R, et al.
    Int J Biol Macromol, 2019 Dec 01;141:185-196.
    PMID: 31479667 DOI: 10.1016/j.ijbiomac.2019.08.255
    Lignin was extracted from coconut husk via alkaline pulping, either Kraft or soda. The isolated lignin samples were classified as hydroxy-benzaldehyde, vanillin, and syringaldehyde type according to Fourier-transform Infrared Spectroscopy, 1H and 13C Nuclear Magnetic Resonance (NMR) spectra. Soda lignin (SL) showed higher thermal stability and glass transition temperature (Tg) than Kraft lignin (KL) as proven by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively. The soda-lignin-phenol-glyoxal (SLPG) resins with the optimum percentage of lignin substitution at 30% showed improved solid content and gel time in comparison to 30% of Kraft-lignin-phenol-glyoxal (KLPG) and phenol-glyoxal (PG) resin. The good mechanical properties in SLPG is due to the higher amount of molecular weight as well as higher phenolic and G-type unit in lignin that improve the properties of 30% SLPG adhesive. Moreover, the addition of layered double hydroxides (LDH) as reinforced filler up to 15%-30% SLPG adhesive blend shows a great performance (especially mechanical properties) as compared to 30% SLPG adhesive alone.
    Matched MeSH terms: Adhesives/chemistry*; Cocos/chemistry*; Glyoxal/chemistry*; Lignin/chemistry*; Seeds/chemistry; Phenol/chemistry*
  18. Zainol Abidin MN, Goh PS, Said N, Ismail AF, Othman MHD, Hasbullah H, et al.
    ACS Appl Mater Interfaces, 2020 Jul 22;12(29):33276-33287.
    PMID: 32589391 DOI: 10.1021/acsami.0c08947
    The development of wearable artificial kidney demands an efficient dialysate recovery, which relies upon the adsorption process. This study proposes a solution to solve the problem of competitive adsorption between the uremic toxins by employing two adsorptive components in a membrane separation process. Dual-layer hollow fiber (DLHF) membranes, which are composed of a polysulfone (PSf)/activated carbon (AC) inner layer and a PSf/poly(methyl methacrylate) (PMMA) outer layer, were prepared for co-adsorptive removal of creatinine and urea from aqueous solution. The DLHF membranes were characterized in terms of morphological, physicochemical, water transport, and creatinine adsorption properties. The membrane was then subjected to an ultrafiltration adsorption study for performance evaluation. The incorporation of AC in membrane, as confirmed by microscopic and surface analyses, has improved the pure water flux up to 25.2 L/(m2 h). A membrane with optimum AC loading (9 wt %) demonstrated the highest maximum creatinine adsorption capacity (86.2 mg/g) based on the Langmuir adsorption isotherm model. In the ultrafiltration adsorption experiment, the membrane removed creatinine and urea with a combined average percent removal of 29.3%. Moreover, the membrane exhibited creatinine and urea uptake recoveries of 98.8 and 81.2%, respectively. The combined action of PMMA and AC in the PSf DLHF membrane has made the adsorption of multiple uremic toxins possible during dialysate recovery.
    Matched MeSH terms: Carbon/chemistry*; Creatinine/chemistry*; Polymers/chemistry*; Sulfones/chemistry*; Urea/chemistry*; Polymethyl Methacrylate/chemistry*
  19. Kim YM, Abas F, Park YS, Park YK, Ham KS, Kang SG, et al.
    Molecules, 2021 Jul 21;26(15).
    PMID: 34361562 DOI: 10.3390/molecules26154405
    Fruit used in the common human diet in general, and kiwifruit and persimmon particularly, displays health properties in the prevention of heart disease. This study describes a combination of bioactivity, multivariate data analyses and fluorescence measurements for the differentiating of kiwifruit and persimmon, their quenching and antioxidant properties. The metabolic differences are shown, as well in the results of bioactivities and antioxidant capacities determined by ABTS, FRAP, CUPRAC and DPPH assays. To complement the bioactivity of these fruits, the quenching properties between extracted polyphenols and human serum proteins were determined by 3D-fluorescence spectroscopy studies. These properties of the extracted polyphenols in interaction with the main serum proteins in the human metabolism (human serum albumin (HSA), α-β-globulin (α-β G) and fibrinogen (Fgn)), showed that kiwifruit was more reactive than persimmon. There was a direct correlation between the quenching properties of the polyphenols of the investigated fruits with serum human proteins, their relative quantification and bioactivity. The results of metabolites and fluorescence quenching show that these fruits possess multiple properties that have a great potential to be used in industry with emphasis on the formulation of functional foods and in the pharmaceutical industry. Based on the quenching properties of human serum proteins with polyphenols and recent reports in vivo on human studies, we hypothesize that HSA, α-β G and Fgn will be predictors of coronary artery disease (CAD).
    Matched MeSH terms: Antioxidants/chemistry*; Fruit/chemistry*; Plant Extracts/chemistry*; Actinidia/chemistry*; Diospyros/chemistry*; Polyphenols/chemistry*
  20. Rizal S, Mistar EM, Oyekanmi AA, H P S AK, Alfatah T, Olaiya NG, et al.
    Molecules, 2021 Jul 13;26(14).
    PMID: 34299524 DOI: 10.3390/molecules26144248
    The use of chemical modification of cellulosic fibre is applied in order to increase the hydrophobicity, hence improving the compatibility between the fibre and matrix bonding. In this study, the effect of propionic anhydride modification of kenaf fibre was investigated to determine the role of bionanocarbon from oil palm shell agricultural wastes in the improvement of the functional properties of bionanocomposites. The vinyl esters reinforced with unmodified and propionic anhydride modified kenaf fibres bio nanocomposites were prepared using 0, 1, 3, 5 wt% of bio-nanocarbon. Characterisation of the fabricated bionanocomposite was carried out using FESEM, TEM, FT-IR and TGA to investigate the morphological analysis, surface properties, functional and thermal analyses, respectively. Mechanical performance of bionanocomposites was evaluated according to standard methods. The chemical modification of cellulosic fibre with the incorporation of bionanocarbon in the matrix exhibited high enhancement of the tensile, flexural, and impact strengths, for approximately 63.91%, 49.61% and 54.82%, respectively. The morphological, structural and functional analyses revealed that better compatibility of the modified fibre-matrix interaction was achieved at 3% bionanocarbon loading, which indicated improved properties of the bionanocomposite. The nanocomposites exhibited high degradation temperature which signified good thermal stability properties. The improved properties of the bionanocomposite were attributed to the effect of the surface modification and bionanocarbon enhancement of the fibre-matrix networks.
    Matched MeSH terms: Anhydrides/chemistry*; Carbon/chemistry; Cellulose/chemistry*; Propionates/chemistry*; Hibiscus/chemistry*; Nanocomposites/chemistry*
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links