Sample records for magnetic gellan gum

  1. The dietary effects of gellan gum in humans.

    PubMed

    Anderson, D M; Brydon, W G; Eastwood, M A

    1988-01-01

    Following a 7-day control period, five female and five male volunteers consumed a weight of gellan gum corresponding to 175 mg/kg body weight for 7 days, followed by 200 mg gellan gum per kg body weight for a further 16 days. Measurements before and at the end of the 23-day test period showed that the gellan gum acted as a faecal bulking agent for the male volunteers and for four of the females. Dietary transit time increased for 2 females and 2 males, and decreased for 3 females and 3 males. Faecal bile acid concentrations increased for 4 females and for 4 males; the average increases were from 0.69 to 0.83 mmol/24 h (females) and from 1.22 to 1.44 mmol/24 h (males). Gellan gum ingestion had no significant effect on (a) plasma biochemistry parameters; (b) haematological indices; (c) urinalysis parameters; (d) blood glucose and plasma insulin concentrations; (e) breath hydrogen concentrations. There were no significant changes in HDL cholesterol, triglyceride or phospholipid concentrations. Serum cholesterol concentrations decreased significantly (P less than 0.1) by 13% on average for females, and by 12%, on average, for males. The data indicate that the ingestion of gellan gum at a high level for 23 days caused no adverse dietary or physiological effects in any of the volunteers. In particular, the enzymatic and other indicators of adverse toxicological effects remained unchanged. PMID:3294053

  2. Injectable Gellan Gum Hydrogels with Autologous Cells for the Treatment of Rabbit Articular Cartilage Defects

    Microsoft Academic Search

    Joao T. Oliveira; Leandro S. Gardel; Tommaso Rada; Luis Martins; Manuela E. Gomes; Rui L. Reis

    2010-01-01

    In this work, the ability of gellan gum hydrogels coupled with\\u000d\\u000a autologous cells to regenerate rabbit full-thickness articular cartilage\\u000d\\u000a defects was tested. Five study groups were defined: (a) gellan gum with\\u000d\\u000a encapsulated chondrogenic predifferentiated rabbit adipose stem cells\\u000d\\u000a (ASC + GF); (b) gellan gum with encapsulated nonchondrogenic\\u000d\\u000a predifferentiated rabbit adipose stem cells (ASC); (c) gellan gum with\\u000d\\u000a encapsulated rabbit articular

  3. Activated sludge encapsulation in gellan gum microbeads for gasoline biodegradation.

    PubMed

    Moslemy, Peyman; Guiot, Serge R; Neufeld, Ronald J

    2004-07-01

    A two-phase dispersion technique, termed emulsification-internal gelation, is proposed for encapsulation of activated sludge in gellan gum microbeads. The influence of emulsion parameters on size distribution of microbeads was investigated. Mean diameter of microbeads varied within a range of 34-265 microm as a descending function of emulsion stirring rate (1,000-5,000 rpm), emulsification time (10-40 min), and emulsifier concentration (0-0.1% w/w), and as an ascending function of disperse phase volume fraction (0.08-0.25). Encapsulated sludge expressed a high biodegradation activity compared with non-encapsulated sludge cultures even at 4.4 times lower level of overall biomass loading. Over 90% of gasoline at an initial concentration of 35 and 70 mg l(-1) was removed by both encapsulated and non-encapsulated sludge cultures in sealed serum bottles within 7 days. Encapsulation of activated sludge in gellan gum microbeads enhanced the biological activity of microbial populations in the removal of gasoline hydrocarbons. The results of this study demonstrated the feasibility of the production of size-controlled gellan gum-encapsulated sludge microbeads and their use in the biodegradation of gasoline. PMID:15133730

  4. 21 CFR 172.665 - Gellan gum.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (a) The additive is a high molecular weight polysaccharide gum produced from Pseudomonas elodea by a pure culture fermentation process and purified by recovery with isopropyl alcohol. It is composed of tetrasaccharide repeat units, each...

  5. 21 CFR 172.665 - Gellan gum.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (a) The additive is a high molecular weight polysaccharide gum produced from Pseudomonas elodea by a pure culture fermentation process and purified by recovery with isopropyl alcohol. It is composed of tetrasaccharide repeat units, each...

  6. Modeling for Gellan Gum Production by Sphingomonas paucimobilis ATCC 31461 in a Simplified Medium

    PubMed Central

    Wang, Xia; Xu, Ping; Yuan, Yong; Liu, Changlong; Zhang, Dezhong; Yang, Zhengting; Yang, Chunyu; Ma, Cuiqing

    2006-01-01

    Gellan gum production was carried out by Sphingomonas paucimobilis ATCC 31461 in a simplified medium with a short incubation time, and a kinetic model for understanding, controlling, and optimizing the fermentation process was proposed. The results revealed that glucose was the best carbon source and that the optimal concentration was 30 g liter?1. As for the fermenting parameters, considerably large amounts of gellan gum were yielded by an 8-h-old culture and a 4% inoculum at 200 rpm on a rotary shaker. Under the optimized conditions, the maximum level of gellan gum (14.75 g liter?1) and the highest conversion efficiency (49.17%) were obtained in a 30-liter fermentor in batch fermentation. Logistic and Luedeking-Piret models were confirmed to provide a good description of gellan gum fermentation, which gave some support for the study of gellan gum fermentation kinetics. Additionally, this study is the first demonstration that gellan gum production is largely growth associated by analysis of kinetics in its batch fermentation process. Based on model prediction, higher gellan gum production (17.71 g liter?1) and higher conversion efficiency (57.12%) were obtained in fed-batch fermentation at the same total glucose concentration (30 g liter?1). PMID:16672479

  7. Biodegradation of gasoline by gellan gum-encapsulated bacterial cells.

    PubMed

    Moslemy, Peyman; Neufeld, Ronald J; Guiot, Serge R

    2002-10-20

    Encapsulated cell bioaugmentation is a novel alternative solution to in situ bioremediation of contaminated aquifers. This study was conducted to evaluate the feasibility of such a remediation strategy based on the performance of encapsulated cells in the biodegradation of gasoline, a major groundwater contaminant. An enriched bacterial consortium, isolated from a gasoline-polluted site, was encapsulated in gellan gum microbeads (16-53 microm diameter). The capacity of the encapsulated cells to degrade gasoline under aerobic conditions was evaluated in comparison with free (non-encapsulated) cells. Encapsulated cells (2.6 mg(cells) x g(-1) bead) degraded over 90% gasoline hydrocarbons (initial concentration 50-600 mg x L(-1)) within 5-10 days at 10 degrees C. Equivalent levels of free cells removed comparable amounts of gasoline (initial concentration 50-400 mg x L(-1)) within the same period but required up to 30 days to degrade the highest level of gasoline tested (600 mg x L(-1)). Free cells exhibited a lag phase in biodegradation, which increased from 1 to 5 days with an increase in gasoline concentration (200-600 x mg L(-1)). Encapsulation provided cells with a protective barrier against toxic hydrocarbons, eliminating the adaptation period required by free cells. The reduction of encapsulated cell mass loading from 2.6 to 1.0 mg(cells) x g(-1) bead caused a substantial decrease in the extent of biodegradation within a 30-day incubation period. Encapsulated cells dispersed within the porous soil matrix of saturated soil microcosms demonstrated a reduced performance in the removal of gasoline (initial concentrations of 400 and 600 mg x L(-1)), removing 30-50% gasoline hydrocarbons compared to 40-60% by free cells within 21 days of incubation. The results of this study suggest that gellan gum-encapsulated bacterial cells have the potential to be used for biodegradation of gasoline hydrocarbons in aqueous systems. PMID:12209773

  8. Multi-modality gellan gum-based tissue-mimicking phantom with targeted mechanical, electrical, and thermal properties

    NASA Astrophysics Data System (ADS)

    Chen, Roland K.; Shih, A. J.

    2013-08-01

    This study develops a new class of gellan gum-based tissue-mimicking phantom material and a model to predict and control the elastic modulus, thermal conductivity, and electrical conductivity by adjusting the mass fractions of gellan gum, propylene glycol, and sodium chloride, respectively. One of the advantages of gellan gum is its gelling efficiency allowing highly regulable mechanical properties (elastic modulus, toughness, etc). An experiment was performed on 16 gellan gum-based tissue-mimicking phantoms and a regression model was fit to quantitatively predict three material properties (elastic modulus, thermal conductivity, and electrical conductivity) based on the phantom material's composition. Based on these material properties and the regression model developed, tissue-mimicking phantoms of porcine spinal cord and liver were formulated. These gellan gum tissue-mimicking phantoms have the mechanical, thermal, and electrical properties approximately equivalent to those of the spinal cord and the liver.

  9. Development of mucoadhesive sprayable gellan gum fluid gels.

    PubMed

    Mahdi, Mohammed H; Conway, Barbara R; Smith, Alan M

    2015-07-01

    The nasal mucosa provides a potentially good route for local and systemic drug delivery. However, the protective feature of the nasal cavity make intranasal delivery challenging. The application of mucoadhesive polymers in nasal drug delivery systems enhances the retention of the dosage form in the nasal cavity. Several groups have investigated using low acyl gellan as a drug delivery vehicle but only limited research however, has been performed on high acyl gellan for this purpose, despite its properties being more conducive to mucoadhesion. High acyl gellan produces highly elastic gels below 60°C which make it difficult to spray using a mechanical spray device. Therefore, in this study we have tried to address this problem by making fluid gels by introducing a shear force during gelation of the gellan polymer. These fluid gel systems contain gelled micro-particles suspended in a solution of un-gelled polymer. These systems can therefore behave as pourable viscoelastic fluids. In this study we have investigated the rheological behavior and mucoadhesion of fluid gels of two different types of gellan (high and low acyl) and fluid gels prepared from blends of high and low acyl gellan at a 50:50 ratio. The results demonstrated that by preparing fluid gels of high acyl gellan, the rheological properties were sufficient to spray through a standard nasal spray device. Moreover fluid gels also significantly enhance both high acyl and low acyl gellan mucoadhesion properties. PMID:25863119

  10. Measurement of stress and strain during tensile testing of gellan gum gels: effect of deformation speed

    Microsoft Academic Search

    M Teratsubo; Y Tanaka; S Saeki

    2002-01-01

    Tensile tests were carried out on gellan gum gels of concentration 2% in order to observe the relation between deformation speed and deformation properties such as tensile modulus and rupture strain. The primary objective of this experiment is to show the validity of the measurement for the actual strain and strain rate during tensile tests. The tensile modulus decreased with

  11. Influence of fermentation hydrodynamics on gellan gum physico-chemical characteristics

    Microsoft Academic Search

    Eric Dreveton; Frédéric Monot; Jacqueline Lecourtier; Daniel Ballerini; Lionel Choplin

    1996-01-01

    The physico-chemical characteristics of gellan gum polymers produced using various impeller systems and different aeration conditions were studied. The degree of esterification, average molecular weight (Mw), intrinsic viscosity ([?]), and molecular weight distribution of the highly clarified polymers were found to be greatly dependent upon the fermentor hydrodynamics. For example, the highly homogeneous conditions of fermentation obtained with a helical

  12. Biological evaluation of intervertebral disc cells in different formulations of gellan gum-based hydrogels.

    PubMed

    Khang, G; Lee, S K; Kim, H N; Silva-Correia, J; Gomes, M E; Viegas, C A A; Dias, I R; Oliveira, J M; Reis, R L

    2015-03-01

    Gellan gum (GG)-based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine-tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG-MA) and high-acyl gellan gums (HA-GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA-GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA-GG content induced greater weight loss in the GG-MA/HA-GG formulation compared to GG-MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein-AM and ATP assays. Results showed that tunable GG-MA/HA-GG hydrogels were non-cytotoxic and supported viability of rabbit NP cells. PMID:23225767

  13. Brevifollis gellanilyticus gen. nov., sp. nov., a gellan-gum-degrading bacterium of the phylum Verrucomicrobia.

    PubMed

    Otsuka, Shigeto; Suenaga, Taku; Vu, Hoan Thi; Ueda, Hiroyuki; Yokota, Akira; Senoo, Keishi

    2013-08-01

    The taxonomic properties of strain DC2c-G4(T), a Gram-staining-negative, ovoid, gellan-gum-degrading bacterial isolate, were examined. Phylogenetic analysis based on 16S rRNA gene sequences identified this isolate as a member of the phylum Verrucomicrobia and closest to the genus Prosthecobacter. The 16S rRNA gene sequence similarities between this isolate and any of the type strains of species of the genus Prosthecobacter were less than 95 %. In addition, the absence of a single prostheca and the predominant menaquinone MK-7(H2) supported the differentiation of this isolate from the genus Prosthecobacter. Here, we propose Brevifollis gellanilyticus gen. nov., sp. nov. to accommodate the isolate. The type strain of the type species is DC2c-G4(T) (= NBRC 108608(T) = CIP 110457(T)). PMID:23416572

  14. Physicochemical studies of glucose, gellan gum, and hydroxypropyl cellulose--inhibition of cast iron corrosion.

    PubMed

    Rajeswari, Velayutham; Kesavan, Devarayan; Gopiraman, Mayakrishnan; Viswanathamurthi, Periasamy

    2013-06-01

    Glucose, gellan gum, and hydroxypropyl cellulose were studied against the acid corrosion of cast iron by means of weight loss, potentiodynamic polarization, and AC impedance spectroscopy techniques. The inhibition efficiency was found to increase with increasing concentration of the inhibitors. The effect of immersion time and temperature were also studied. The addition of potassium iodide to the corrosion-inhibition system showed both antagonism and synergism toward inhibition efficiency. Polarization studies revealed the mixed-type inhibiting nature of the carbohydrates. The adsorption of inhibitors on the cast iron surface obeys Langmuir adsorption isotherm model, both in presence and absence of KI. Physical interaction between the inhibitor molecules and the iron surface was suggested by the thermochemical parameters, rather than chemical interaction. PMID:23618271

  15. Effect of sugars, amino acids, and culture technique on maturation of somatic embryos of Pinus strobus on medium with two gellan gum concentrations

    Microsoft Academic Search

    Élisabeth Garin; Michèle Bernier-Cardou; Nathalie Isabel; Krystyna Klimaszewska; Ariane Plourde

    2000-01-01

    Maturation of five embryogenic lines of Pinus strobus L. was tested on media with various sugars and sources of organic nitrogen, and solidified with two gellan gum concentrations\\u000a (0.6 and 1.0%). Mature somatic embryo production was more abundant at 1.0% gellan gum than at 0.6%. Complex combinations of\\u000a amino acids had little effect on mature embryo production of most tested

  16. Mucoadhesive beads of gellan gum/pectin intended to controlled delivery of drugs.

    PubMed

    Prezotti, Fabíola Garavello; Cury, Beatriz Stringhetti Ferreira; Evangelista, Raul Cesar

    2014-11-26

    Gellan gum/pectin beads were prepared by ionotropic gelation, using Al(3+) as crosslinker. High yield (92.76%) and entrapment efficiency (52.22-88.78%) were reached. Beads exhibited high circularity (0.730-0.849) and size between 728.95 and 924.56 ?m. Particle size and circularity was increased by raising polymer and crosslinker concentrations. Polymers ratio did not influence beads properties. The materials stability and the absence of drug-polymers interactions were evidenced by thermal analysis and FTIR. The high beads mucoadhesiveness was evidenced by in vitro and ex vivo tests. The erosion of beads was greater in acid media while swelling was more pronounced in pH 7.4. Drug release was dependent on pH in which samples 11H1-3, 11H1-5 and 41H1-3 released only 34%, 20% and 22% of ketoprofen in pH 1.2, while in pH 7.4 the drug release was sustained up to 360 min. Korsmeyer-Peppas model demonstrated that drug release occurred according to super case-II transport. PMID:25256487

  17. Artocarpus heterophyllus L. seed starch-blended gellan gum mucoadhesive beads of metformin HCl.

    PubMed

    Nayak, Amit Kumar; Pal, Dilipkumar; Santra, Kousik

    2014-04-01

    Jackfruit (Artocarpus heterophyllus Lam., family: Moraceae) seed starch (JFSS)-gellan gum (GG) mucoadhesive beads containing metformin HCl were developed through ionotropic gelation technique. The effect of GG to JFSS ratio and CaCl2 concentration on the drug encapsulation efficiency (DEE, %) and cumulative drug release at 10h (R10h, %) was optimized and analyzed using response surface methodology based on 3(2) factorial design. The optimized JFSS-GG beads containing metformin HCl showed DEE of 92.67±4.46%, R10h of 61.30±2.37%, and mean diameter of 1.67±0.27 mm. The optimized beads showed pH-dependent swelling and mucoadhesivity with the goat intestinal mucosa. The in vitro drug release from all these JFSS-GG beads containing metformin HCl was followed zero-order pattern (R(2)=0.9907-0.9975) with super case-II transport mechanism over a period of 10 h. The beads were also characterized by SEM and FTIR. The optimized JFSS-GG beads containing metformin HCl exhibited significant hypoglycemic effect in alloxan-induced diabetic rats over prolonged period after oral administration. PMID:24447799

  18. The effects of peptide modified gellan gum and olfactory ensheathing glia cells on neural stem/progenitor cell fate.

    PubMed

    Silva, Nuno A; Cooke, Michael J; Tam, Roger Y; Sousa, Nuno; Salgado, António J; Reis, Rui L; Shoichet, Molly S

    2012-09-01

    The regenerative capacity of injured adult central nervous system (CNS) tissue is very limited. Specifically, traumatic spinal cord injury (SCI) leads to permanent loss of motor and sensory functions below the site of injury, as well as other detrimental complications. A potential regenerative strategy is stem cell transplantation; however, cell survival is typically less than 1%. To improve cell survival, stem cells can be delivered in a biomaterial matrix that provides an environment conducive to survival after transplantation. One major challenge in this approach is to define the biomaterial and cell strategies in vitro. To this end, we investigated both peptide-modification of gellan gum and olfactory ensheathing glia (OEG) on neural stem/progenitor cell (NSPC) fate. To enhance cell adhesion, the gellan gum (GG) was modified using Diels-Alder click chemistry with a fibronectin-derived synthetic peptide (GRGDS). Amino acid analysis demonstrated that approximately 300 nmol of GRGDS was immobilized to each mg of GG. The GG-GRGDS had a profound effect on NSPC morphology and proliferation, distinct from that of NSPCs in GG alone, demonstrating the importance of GRGDS for cell-GG interaction. To further enhance NSPC survival and outgrowth, they were cultured with OEG. Here NSPCs interacted extensively with OEG, demonstrating significantly greater survival and proliferation relative to monocultures of NSPCs. These results suggest that this co-culture strategy of NSPCs with OEG may have therapeutic benefit for SCI repair. PMID:22698724

  19. Development of gellan gum-based microparticles/hydrogel matrices for application in the intervertebral disc regeneration.

    PubMed

    Pereira, Diana Ribeiro; Silva-Correia, Joana; Caridade, Sofia Glória; Oliveira, Joao T; Sousa, Rui A; Salgado, Antonio J; Oliveira, Joaquim M; Mano, João F; Sousa, Nuno; Reis, Rui L

    2011-10-01

    Low back pain is one of the most reported medical conditions associated to intervertebral disc (IVD) degeneration. Nucleus pulposus (NP) is often regarded as the structure where IVD degeneration begins. Gellan gum (GG)-based hydrogels for acellular and cellular tissue engineering strategies have been developed for finding applications as NP substitutes. The innovative strategy is based on the reinforcement of the hydrogel matrix with biocompatible and biodegradable GG microparticles (MPs), which are expected to improve the mechanical properties, while allowing to tailor its degradation rate. In this study, several GG MP/hydrogel disc formulations were prepared by means of mixing high acyl GG (0.75% (w/v)) and low acyl GG (2% (w/v)) GG aqueous solutions at different ratios, namely, 75%:25% (v/v), 50%:50% (v/v), and 25%:75% (v/v), respectively. The GG MP size was measured using a stereo microscope, and their dispersion within the hydrogel matrix was evaluated by means of staining the MPs with Toluidine Blue-O. The developed GG MPs/hydrogel discs were physicochemically characterized by Fourier-transform infrared spectroscopy and (1)H-nuclear magnetic resonance spectroscopy. The swelling behavior and degradation rate were assessed by immersion in a phosphate buffer saline for 14 days. The morphology and mechanical behavior were investigated by scanning electron microscopy and dynamic mechanical analysis, respectively. The mechanical properties of the hydrogel disc were improved by mixing the gels with the MPs. In addition, the possible cytotoxicity of the leachables released by MPs/hydrogel discs was screened in vitro, using a mouse lung fibroblast cell line (L929 cells). To investigate the encapsulation efficacy of L929 cells into the GG MPs/hydrogel discs, cells were stained with DAPI blue/Texas Red-Phalloidin and observed by confocal microscopy, after 24, 48, and 72 h of culturing. A cell viability assay was also performed using Calcein AM staining. The cell culture studies demonstrated that MPs/hydrogel discs are noncytotoxic over L929 cells. It was also demonstrated that L929 cells can be successfully encapsulated into the GG MPs of different formulations, remaining viable after 72 h of culturing. This study showed that GG hydrogel matrices reinforced with cell-loaded MPs could be a candidate strategy for NP regeneration. PMID:21574937

  20. Enzymatic mineralization of gellan gum hydrogel for bone tissue-engineering applications and its enhancement by polydopamine.

    PubMed

    Douglas, T E L; Wlodarczyk, M; Pamula, E; Declercq, H A; de Mulder, E L W; Bucko, M M; Balcaen, L; Vanhaecke, F; Cornelissen, R; Dubruel, P; Jansen, J A; Leeuwenburgh, S C G

    2014-11-01

    Interest is growing in the use of hydrogels as bone tissue-engineering (TE) scaffolds due to advantages such as injectability and ease of incorporation of active substances such as enzymes. Hydrogels consisting of gellan gum (GG), an inexpensive calcium-crosslinkable polysaccharide, have been applied in cartilage TE. To improve GG suitability as a material for bone TE, alkaline phosphatase (ALP), an enzyme involved in mineralization of bone by cleaving phosphate from organic phosphate, was incorporated into GG hydrogels to induce mineralization with calcium phosphate (CaP). Incorporated ALP induced formation of apatite-like material on the submicron scale within GG gels, as shown by FTIR, SEM, EDS, XRD, ICP-OES, TGA and von Kossa staining. Increasing ALP concentration increased amounts of CaP as well as stiffness. Mineralized GG was able to withstand sterilization by autoclaving, although stiffness decreased. In addition, mineralizability and stiffness of GG was enhanced by the incorporation of polydopamine (PDA). Furthermore, mineralization of GG led to enhanced attachment and vitality of cells in vitro while cytocompatibility of the mineralized gels was comparable to one of the most commonly used bone substitute materials. The results proved that ALP-mediated enzymatic mineralization of GG could be enhanced by functionalization with PDA. PMID:23038649

  1. Tranexamic acid loaded gellan gum-based polymeric microbeads for controlled release: in vitro and in vivo assessment.

    PubMed

    Bhattacharya, Shiv Sankar; Banerjee, Subham; Chowdhury, Purojit; Ghosh, Amitava; Hegde, Rahul Rama; Mondal, Ranjit

    2013-12-01

    Gellan gum (GG) microbeads containing tranexamic acid (TA), an anti-fibrinolytic drug were prepared by a classic sol-gel transition induced by ionic crosslinking technique using aluminum chloride (AlCl3) as cross-linking agent. The influence of different formulation variables on in vitro physico-chemical parameters and drug release studies were performed systematically. The microbeads were evaluated by scanning electron microscopy (SEM), Fourier transform infra-red (FTIR) spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and high performance liquid chromatographic (HPLC) analysis. Particle size and swelling behavior of microbeads were also investigated. Microbeads showed improved drug encapsulation efficiency along with enhanced drug release. The in vivo studies exhibited sustained drug release in rabbits over a prolonged period after oral administration of these newly developed TA loaded GG microbeads. Based on the results of in vitro and in vivo studies in experimental animal model it was concluded that these microbeads provided intestinal specific controlled release of TA. PMID:24183265

  2. Novel in situ gel systems based on P123/TPGS mixed micelles and gellan gum for ophthalmic delivery of curcumin.

    PubMed

    Duan, Yuwei; Cai, Xiaoqing; Du, Hongliang; Zhai, Guangxi

    2015-04-01

    Curcumin, a natural polyphenol compound, has been widely reported for diverse pharmacological effects and already been investigated for eye diseases. However, the water-insolubility of curcumin and the inherent penetration barriers in cornea make it difficult for curcumin to enter eye. This work aimed to develop ion-sensitive curcumin-loaded Pluronic P123 (P123)/D-a-tocopheryl polyethylene glycolsuccinate (TPGS) mixed micelle in situ gels (CUR-MM-ISGs) to prolong ocular retention time and improve cornea permeability. Central composite design-response surface methodology was applied for the optimization of curcumin-loaded P123/TPGS mixed micelles (CUR-MMs). Characterization tests showed that CUR-MMs were in spherical shape with small size and low critical micelle concentration. After dispersing the micelles in gellan gum solution (0.2%, w/w) at the ratio of 3:1 and 1:1 (v/v), respectively, CUR-MM-ISGs were formed and presented transparent appearance. Sustained release profile was obtained in vitro for both CUR-MM-ISGs (3:1 or 1:1, v/v). The irritation test proved that CUR-MM-ISGs as ophthalmic formulations were gentle and biocompatible towards ocular tissues. In addition, the ex vivo corneal penetration study indicated that the cumulative drug permeation amount of CUR-MM-ISGs (3:1, v/v) was respectively 1.16-fold and 1.32-fold higher than CUR-MM-ISGs (1:1, v/v) and curcumin solution. It can be concluded from these results that the developed ion-sensitive mixed micelle in situ gel system is a potential ophthalmic delivery carrier for curcumin as a poorly soluble drug. PMID:25707750

  3. Angiogenic potential of gellan-gum-based hydrogels for application in nucleus pulposus regeneration: in vivo study.

    PubMed

    Silva-Correia, Joana; Miranda-Gonçalves, Vera; Salgado, António J; Sousa, Nuno; Oliveira, Joaquim M; Reis, Rui M; Reis, Rui L

    2012-06-01

    Hydrogels for nucleus pulposus (NP) regeneration should be able to comprise a nonangiogenic or even antiangiogenic feature. Gellan gum (GG)-based hydrogels have been reported to possess adequate properties for being used as NP substitutes in acellular and cellular strategies, due to its ability to support cell encapsulation, adequate mechanical properties, and noncytotoxicity. In this study, the angiogenic response of GG-based hydrogels was investigated by performing the chorioallantoic membrane assay. The convergence of macroscopic blood vessels toward the GG, ionic-crosslinked methacrylated GG (iGG-MA), and photo-crosslinked methacrylated GG (phGG-MA) hydrogel discs was quantified. Gelatin sponge (GSp) and filter paper (FP) alone and with vascular endothelial growth factor were used as controls of angiogenesis. The images obtained were digitally processed and analyzed by three independent observers. The macroscopic blood vessel quantification demonstrated that the GG-based hydrogels are not angiogenic as compared with FP controls. No statistical differences between the GG-based hydrogels tested in respect to its angiogenic ability were observed. Hematoxylin and eosin staining and SNA-lectin immunohistochemistry assay indicated that the iGG-MA and phGG-MA hydrogels do not allow the ingrowth of chick endothelial cells, following 4 days of implantation. On the contrary, GG, GSp, and FP controls allowed cell infiltration. The histological data also indicated that the GG-based hydrogels do not elicit any acute inflammatory response. The results showed that the GG, iGG-MA, and phGG-MA hydrogels present different permeability to cells but functioned as a physical barrier for vascular invasion. These hydrogels present promising and tunable properties for being used as NP substitutes in the treatment of degenerative intervertebral disc. PMID:22439824

  4. Human skin cell fractions fail to self-organize within a gellan gum/hyaluronic acid matrix but positively influence early wound healing.

    PubMed

    Cerqueira, Mariana T; da Silva, Lucília P; Santos, Tírcia C; Pirraco, Rogério P; Correlo, Vitor M; Marques, Alexandra P; Reis, Rui L

    2014-05-01

    Split-thickness autografts still are the current gold standard to treat skin, upon severe injuries. Nonetheless, autografts are dependent on donor site availability and often associated to poor quality neoskin. The generation of dermal-epidermal substitutes by tissue engineering is seen as a promising strategy to overcome this problematic. However, solutions that can be safely and conveniently transplanted in one single surgical intervention are still very challenging as their production normally requires long culture time, and graft survival is many times compromised by delayed vascularization upon transplantation. This work intended to propose a strategy that circumvents the prolonged and laborious preparation period of skin substitutes and allows skin cells self-organization toward improved healing. Human dermal/epidermal cell fractions were entrapped directly from isolation within a gellan gum/hyaluronic acid (GG-HA) spongy-like hydrogel formed from an off-the-shelf dried polymeric network. Upon transplantation into full-thickness mice wounds, the proposed constructs accelerated the wound closure rate and re-epithelialization, as well as tissue neovascularization. A synergistic effect of the GG-HA matrix and the transplanted cells over those processes was demonstrated at early time points. Despite the human-derived and chimeric blood vessels found, the proposed matrix did not succeed in prolonging cells residence time and in sustaining the self-organization of transplanted human cells possibly due to primitive degradation. Despite this, the herein proposed approach open the opportunity to tackle wound healing at early stages contributing to re-epithelialization and neovascularization. PMID:24299468

  5. Gellan gum-based mucoadhesive microspheres of almotriptan for nasal administration: Formulation optimization using factorial design, characterization, and in vitro evaluation

    PubMed Central

    Abbas, Zaheer; Marihal, Sachin

    2014-01-01

    Background: Almotriptan malate (ALM), indicated for the treatment of migraine in adults is not a drug candidate feasible to be administered through the oral route during the attack due to its associated symptoms such as nausea and vomiting. This obviates an alternative dosage form and nasal drug delivery is a good substitute to oral and parenteral administration. Materials and Methods: Gellan gum (GG) microspheres of ALM, for intranasal administration were prepared by water-in-oil emulsification cross-linking technique employing a 23 factorial design. Drug to polymer ratio, calcium chloride concentration and cross-linking time were selected as independent variables, while particle size and in vitro mucoadhesion of the microspheres were investigated as dependent variables. Regression analysis was performed to identify the best formulation conditions. The microspheres were evaluated for characteristics such as practical percentage yield, particle size, percentage incorporation efficiency, swellability, zeta potential, in vitro mucoadhesion, thermal analysis, X-ray diffraction study, and in vitro drug diffusion studies. Results: The shape and surface characteristics of the microspheres were determined by scanning electron microscopy, which revealed spherical nature and nearly smooth surface with drug incorporation efficiency in the range of 71.65 ± 1.09% – 91.65 ± 1.13%. In vitro mucoadhesion was observed the range of 79.45 ± 1.69% – 95.48 ± 1.27%. Differential scanning calorimetry and X-ray diffraction results indicated a molecular level dispersion of drug in the microspheres. In vitro drug diffusion was Higuchi matrix controlled and the release mechanism was found to be non-Fickian. Stability studies indicated that there were no significant deviations in the drug content, in vitro mucoadhesion and in vitro drug diffusion characteristics. Conclusion: The investigation revealed promising potential of GG microspheres for delivering ALM intranasally for the treatment of migraine. PMID:25400410

  6. Survival of bifidobacteria in yogurt and simulated gastric juice following immobilization in gellan–xanthan beads

    Microsoft Academic Search

    Wenrong Sun; Mansel W Griffiths

    2000-01-01

    A novel acid-stable bead made of gellan gum and xanthan gum was used to immobilize Bifidobacteria. The beads (0.75% gellan and 1% xanthan gum) had an average diameter of 3 mm and did not shrink in 25% lactic acid solution, pH 1.5, or 20% acetic acid solution, pH 1.5, after storage at 4°C for 4 weeks. Bifidobacterium infantis ATCC 15697,

  7. Structures and Properties of Gellan Polymers Produced by Sphingomonas paucimobilis ATCC 31461 from Lactose Compared with Those Produced from Glucose and from Cheese Whey

    Microsoft Academic Search

    ARSENIO M. FIALHO; LIGIA O. MARTINS; MARIE-LUCIE DONVAL; JORGE H. LEITAO; MICHAEL J. RIDOUT; ANDREW J. JAY; VICTOR J. MORRIS; ISABEL SA ´-CORREIA

    1999-01-01

    The dairy industry produces large quantities of whey as a by-product of cheese production and is increas- ingly looking for new ways to utilize this waste product. Gellan gum is reliably produced by Sphingomonas paucimobilis in growth media containing lactose, a significant component of cheese whey, as a carbon source. We studied and compared polysaccharide biosynthesis by S. paucimobilis ATCC

  8. Magnetorheology of xanthan-gum-coated soft magnetic carbonyl iron microspheres and their polishing characteristics

    NASA Astrophysics Data System (ADS)

    Kwon, Seung Hyuk; Choi, Hyoung Jin; Lee, Jung Won; Hong, Kwang Pyo; Cho, Myeong Woo

    2013-06-01

    Magnetorheological (MR) fluids are colloidal suspensions of soft magnetic particles dispersed in a non-magnetic liquid. Among their applications, MR polishing has attracted considerable attention owing to its smart control of the polishing characteristics for dedicated microelectromechanical system applications. To improve the polishing characteristics of MR fluids, we fabricated carbonyl iron (CI) microspheres coated with xanthan gum (XG) by using a solvent casting method. The morphologies and densities of both pure CI and CI/XG particles were characterized using a scanning electron microscope and a pycnometer, respectively. In addition, the rheological characteristics of the MR fluids under various applied magnetic field strengths were examined using a rotational rheometer. The MR polishing characteristics were conducted using an MR polishing machine to examine the surface roughness and the material removal by MR polishing with added nano-ceria slurry abrasives.

  9. Nicotine Gum

    MedlinePLUS

    Nicotine chewing gum is used to help people stop smoking cigarettes. Nicotine chewing gum should be used together with a ... support groups, counseling, or specific behavioral change techniques. Nicotine gum is in a class of medications called ...

  10. Spontaneous synthesis of gold nanoparticles on gum arabic-modified iron oxide nanoparticles as a magnetically recoverable nanocatalyst

    PubMed Central

    2012-01-01

    A novel magnetically recoverable Au nanocatalyst was fabricated by spontaneous green synthesis of Au nanoparticles on the surface of gum arabic-modified Fe3O4 nanoparticles. A layer of Au nanoparticles with thickness of about 2?nm was deposited on the surface of gum arabic-modified Fe3O4 nanoparticles, because gum arabic acted as a reducing agent and a stabilizing agent simultaneously. The resultant magnetically recoverable Au nanocatalyst exhibited good catalytic activity for the reduction of 4-nitrophenol with sodium borohydride. The rate constants evaluated in terms of pseudo-first-order kinetic model increased with increase in the amount of Au nanocatalyst or decrease in the initial concentration of 4-nitrophenol. The kinetic data suggested that this catalytic reaction was diffusion-controlled, owing to the presence of gum arabic layer. In addition, this nanocatalyst exhibited good stability. Its activity had no significant decrease after five recycles. This work is useful for the development and application of magnetically recoverable Au nanocatalyst on the basis of green chemistry principles. PMID:22713480

  11. Nanometric organisation in blends of gellan/xyloglucan hydrogels.

    PubMed

    de Souza, Clayton F; Riegel-Vidotti, Izabel C; Cardoso, Mateus B; Ono, Lucy; Lucyszyn, Neoli; Lubambo, Adriana F; Sens, Camila V; Grein-Iankovski, Aline; Sierakowski, Maria Rita

    2014-12-19

    Mixtures of gellan gum (GL) and a xyloglucan (XGJ) extracted from Hymenaea courbaril seeds were prepared in a solution of 0.15 mol L(-1) NaCl. Rheology measurements revealed that 2.4 g L(-1) pure GL formed a brittle hydrogel, and GL-XGJ blends showed improved pseudoplastic character with higher XGJ contents. SAXS analyses showed that the Rg dimensions ranged from 1.3 to 4.9 nm, with larger values occurring as the amount of XGJ increased, and diffusion tests indicated that better diffusion of methylene blue dye was obtained in the network with a higher XGJ content. AFM topographic images of the films deposited onto mica revealed fewer heterogeneous surfaces with increased XGJ contents. The water contact angle revealed more hydrophobic character on all of the films, and the wettability decreased with increasing amounts of XGJ. Therefore, the demonstrated benefit of using XGJ blends is the production of a soft material with improved interface properties. PMID:25263863

  12. Conformational transition of native and modified gellan.

    PubMed

    Mazen, F; Milas, M; Rinaudo, M

    1999-11-01

    This paper concerns the characterisation of native gellan by differential scanning calorimetry (DSC) and rheology. The stability of the double helix is characterised by Tm and the enthalpy of conformational change. The role of the external salt concentration is investigated; it is shown that Tm is only slightly modified. At ambient temperature, in 10(-2) M NaCl, native gellan behaves as a loose gel (G' > G''). This behaviour disappears when temperature is larger than 60 degrees C. The comparison with deacylated gellan (commercial sample) shows that the position of conformational transition is much more influenced by the salt concentration; the helical structure is less stable and the conformational transition presents a hysteresis between heating and cooling runs when the external salt concentration increases. The rheological behaviour is that corresponding to a solution (G' < G'') at ambient temperature and in 10(-2) M NaCl. When the salt excess increases, then a stronger gel is formed. The differences between the two types of samples are clearly established as well as the relations between the conformation and the rheology of the systems. PMID:10517517

  13. Interpenetrating network formation in gellan--agarose gel composites.

    PubMed

    Amici, E; Clark, A H; Normand, V; Johnson, N B

    2000-01-01

    Thermal, mechanical, turbidity, and microscope evidence is provided which strongly suggests molecular interpenetrating network (IPN) formation by mixtures of the bacterial and seaweed polysaccharides gellan and agarose. There is no evidence for synergistic coupling of the networks, and simple phase separation (demixing) can definitely be ruled out. Some changes in the gellan gelling behavior are suggested, however, by the increased gellan effective concentrations implicit in cure curve data. The dependence of this effect on the agarose nominal concentration seems consistent with a previous model that focused on gelling parameters, and changes in these rather than real concentration effects. In large deformation mechanical tests, the influence of agarose added to gellan is to re-enforce the network (higher compression and shear moduli, higher stresses-to-break) without significantly changing the strain to break, or the gellan brittle failure mechanism. PMID:11710203

  14. Gum (Periodontal) Disease

    MedlinePLUS

    ... Disease: What Is Gum (Periodontal) Disease? In This Topic What Is Gum (Periodontal) Disease? Risk Factors and ... for More Information National Institute on Aging Related Topics Problems with Taste The information in this topic ...

  15. Gum Disease in Children

    MedlinePLUS

    ... in children. It usually causes gum tissue to swell, turn red and bleed easily. Gingivitis is both ... through puberty, the tendency for the gums to swell in response to irritants will lessen. However, during ...

  16. Chew that Gum

    NSDL National Science Digital Library

    2012-05-09

    In this quick activity, learners will investigate what happens to bubble gum when it is chewed for 5-10 minutes. First, learners measure the weight of unwrapped pieces on a kitchen scale and recorded. Then learners chew the gum for 5-10 minutes and record the new weight. Learners are encouraged to compare sugarless gum with regular gum as well as different brands. Relates to the linked video, DragonflyTV: Exercise and Memory.

  17. Internists and nicotine gum.

    PubMed

    Cummings, S R; Hansen, B; Richard, R J; Stein, M J; Coates, T J

    1988-09-16

    Nicotine gum may be a useful aid to help patients quit smoking. The effectiveness of the gum and incidence of side effects may depend on using the gum properly. To describe internists' current practices of prescribing nicotine gum and other drugs for smoking cessation, we surveyed randomly selected internists. Most internists prescribe nicotine gum to fewer than 25% of patients who try to quit smoking. Contrary to current recommendations, nearly half of internists would suggest gum to help patients cut down on smoking, and a majority would limit its use to less than three months. There is no evidence that sedatives are useful for smoking cessation, but one fourth of internists had recently prescribed them for that purpose. There is a widespread need for physician education about how to use nicotine gum more effectively. PMID:3411736

  18. Preparation of the sodium salt of high acyl gellan and characterization of its structure, thermal and rheological behaviors.

    PubMed

    Murillo-Martínez, María M; Tecante, Alberto

    2014-08-01

    This work presents a method to obtain the sodium salt of high acyl gellan (NaHAG) from a commercial preparation, LT-100, by ionic exchange and freeze drying without involving alcohol precipitation to recover the modified macromolecule. NaHAG was characterized by atomic absorption spectrophotometry, attenuated total reflectance Fourier transform infrared spectroscopy, X-ray diffraction and proton nuclear magnetic resonance. In addition, gel viscoelasticity, sol-gel transition temperatures from rheological temperature sweeps and differential scanning calorimetry, of both preparations was examined. Up to 87% of the initial weight of LT-100 was recovered as NaHAG. The sodium ion content in NaHAG was 3.2 times greater than in LT-100 and more than 90% of potassium, calcium and magnesium ions present in the original sample were removed. Transition temperatures of LT-100 were significantly higher than those of NaHAG. However, LT-100 gels were slightly stronger and elastic than NaHAG gels. Characterization data from different analyses suggest that the treatment method makes possible to obtain NaHAG with only slight structure modification with respect to LT-100, and could be advantageously utilized to obtain other monovalent and divalent salt forms of high acyl gellan for use in fundamental studies on its properties in aqueous environment. PMID:24751279

  19. Gum Disease Symptoms

    MedlinePLUS

    ... Gum Disease Regenerative Procedures Dental Crown Lengthening Procedure Dental Implants Single Tooth Implants Multiple Tooth Implants Full Mouth Dental Implants Sinus Augmentation Ridge Modification Periodontal Pocket Reduction Procedures ...

  20. Gum Disease and Women

    MedlinePLUS

    ... Gum Disease Regenerative Procedures Dental Crown Lengthening Procedure Dental Implants Single Tooth Implants Multiple Tooth Implants Full Mouth Dental Implants Sinus Augmentation Ridge Modification Periodontal Pocket Reduction Procedures ...

  1. Preparation and in vitro characterization of gellan based floating beads of acetohydroxamic acid for eradication of H. pylori

    Microsoft Academic Search

    BRAHMESHWAR MISHRA

    Gellan based floating beads of acetohydroxamic acid (AHA) were prepared by the ionotropic gellation me- thod to achieve controlled and sustained drug release for treatment of Helicobacter pylori infection. The prepared beads were evaluated for diameter, surface morphology and encapsulation efficiency. Formulation parameters like concentrations of gellan, chitosan, calcium carbonate and the drug influenced the in vitro drug release charac-

  2. Experimental De gumming Apparatus 

    E-print Network

    Unknown

    2011-08-17

    EFFECT OF GUAR GUM UPON THE PARTITION COEFFICIENTS OF DIACE~ ACETALDEHYDE& AND ETHANOL IN ACIDIFIED MILK PRODUCTS A Thesis by CHIH- YANG LO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE December 1992 Major Subject: Food Science and Technology EFFECT OF GUAR GUM UPON THE PARTITION COEFFICIENTS OF DIACETYL, ACETALDEHYDE, AND ETHANOL IN ACIDIFIED MILK PRODUCTS A Thesis by Chih- Yang Lo...

  3. Modification of palm kernel oil esters nanoemulsions with hydrocolloid gum for enhanced topical delivery of ibuprofen

    PubMed Central

    Salim, Norazlinaliza; Basri, Mahiran; Rahman, Mohd BA; Abdullah, Dzulkefly K; Basri, Hamidon

    2012-01-01

    Introduction During recent years, there has been growing interest in the use of nanoemulsion as a drug-carrier system for topical delivery. A nanoemulsion is a transparent mixture of oil, surfactant and water with a very low viscosity, usually the product of its high water content. The present study investigated the modification of nanoemulsions with different hydrocolloid gums, to enhanced drug delivery of ibuprofen. The in vitro characterization of the initial and modified nanoemulsions was also studied. Methods A palm kernel oil esters nanoemulsion was modified with different hydrocolloid gums for the topical delivery of ibuprofen. Three different hydrocolloids (gellan gum, xanthan gum, and carrageenan) were selected for use. Ternary phase diagrams were constructed using palm kernel oil esters as the oil, Tween 80 as the surfactant, and water. Nanoemulsions were prepared by phase inversion composition, and were gradually mixed with the freshly prepared hydrocolloids. The initial nanoemulsion and modified nanoemulsions were characterized. The abilities of the nanoemulsions to deliver ibuprofen were assessed in vitro, using a Franz diffusion cell fitted with rat skin. Results No significant changes were observed in droplet size (~16–20 nm) but a significant difference in polydispersity indexes were observed before and after the modification of nanoemulsions using gellan gum, carrageenan, and xanthan gum. The zeta potentials of the initial nanoemulsions (?11.0 mV) increased to ?19.6 mV, ?13.9 mV, and ?41.9 mV, respectively. The abilities of both the initial nanoemulsion (T802) and the modified nanoemulsion to deliver ibuprofen through the skin were evaluated in vitro, using Franz diffusion cells fitted with rat skin. The in vitro permeation data showed that the modified nanoemulsion (Kp value of 55.4 × 10?3 cm · h?1) increased the permeability of ibuprofen 4.40 times over T802 (Kp value of 12.6 × 10?3 cm · h?1) (P < 0.05). Conclusion The modified nanoemulsion may be a promising vehicle to enhance the permeation of ibuprofen for topical delivery. PMID:22973096

  4. Alginate- and gellan-based edible films for probiotic coatings on fresh-cut fruits.

    PubMed

    Tapia, M S; Rojas-Graü, M A; Rodríguez, F J; Ramírez, J; Carmona, A; Martin-Belloso, O

    2007-05-01

    Alginate- (2% w/v) or gellan-based (0.5%) edible films, containing glycerol (0.6% to 2.0%), N-acetylcysteine (1%), and/or ascorbic acid (1%) and citric acid (1%), were formulated and used to coat fresh-cut apple and papaya cylinders. Water vapor permeability (WVP) was significantly higher (P < 0.05) in alginate films (0.30 to 0.31 x 10(-9) g m/Pa s m2) than in the gellan ones (0.26 to 0.27 x 10(-9) g m/Pa s m2). Addition of 0.025% (w/v) sunflower oil decreased WVP of gellan films (0.20 to 0.22 x 10(-9) g m/Pa s m2). Water solubility of gellan and alginate films at 25 degrees C (0.47 to 0.59 and 0.74 to 0.79, respectively) and their swelling ratios (2.3 to 2.6 and 1.6 to 2.0, respectively) indicate their potential for coating high moisture fresh-cut fruits. Fresh-cut apple and papaya cylinders were successfully coated with 2% (w/v) alginate or gellan film-forming solutions containing viable bifidobacteria. WVP in alginate (6.31 and 5.52 x 10(-9) g m/Pa s m2) or gellan (3.65 and 4.89 x 10(-9) g m/Pa s m2) probiotic coatings of papaya and apple, respectively, were higher than in the corresponding cast films. The gellan coatings and films exhibited better water vapor properties in comparison with the alginate coatings. Values > 10(6) CFU/g B. lactis Bb-12 were maintained for 10 d during refrigerated storage of fresh-cut fruits, demonstrating the feasibility of alginate- and gellan-based edible coatings to carry and support viable probiotics on fresh-cut fruit. PMID:17995771

  5. Novel plasma-separation dilayer gellan–gellan-sulfate adsorber for direct removal of extra domain A containing fibronectin from the blood of rheumatoid arthritis patients

    Microsoft Academic Search

    Keiichi Miyamoto; Katsuyuki Sugihara; Yasunori Abe; Tsutomu Nobori; Masayuki Tokita; Takashi Komai

    2002-01-01

    Rheumatoid arthritis (RA) patients, in whom cryogelation occurs in the presence of heparin, exhibit abnormally high concentrations of extra domain A containing fibronectin [EDA(+)FN] in their plasma. The selective removal of EDA(+)FN from patient blood is therefore of potential therapeutic benefit. Gellan-sulfate is a candidate ligand for the removal of EDA(+)FN due to its high affinity for FN. In this

  6. Guar Gum Slime

    NSDL National Science Digital Library

    2012-06-26

    In this activity, learners create a gelatinous slime using guar gum powder and borax. Educators can use this simple activity to introduce learners to colloids. This activity page features a fun how-to video that shows learners and educators how to make the slime.

  7. Gum and Heart Disease

    NSDL National Science Digital Library

    Science Update

    2005-04-25

    Scientists have long noticed a connection between gum disease and heart disease. Now, they've found a key piece of the puzzle. This science update examines what scientists have found linking the total amount of periodontal bacteria in the mouth and blockages in the carotid artery.

  8. Tips for Removing Gum without Cutting Hair

    MedlinePLUS

    ... a jar of creamy style peanut butter or vegetable oil, such as olive oil. Cover the gum completely ... to work. Remove the gum from the hair. Vegetable oil is especially useful when removing gum from eyebrows ...

  9. The Gum of Fagara xanthoxyloides

    Microsoft Academic Search

    F. G. Torto

    1957-01-01

    Fagara xanthoxyloides Lam. (Xanthoxylum Senegalense DC.), a common plant in West Africa, exudes a clear yellow gum during the dry season. The gum is partly acetylated and has a significant methoxyl content. A single unpurified nodule gave, on analysis, acetyl groups, 6.95 per cent; methoxyl groups, 2.6 per cent. The nodules dissolve with difficulty in water to give a viscous

  10. Gum and Heart Disease

    NSDL National Science Digital Library

    American Association for the Advancement of Science (; )

    2005-04-25

    Over the past ten years, there have been many studies linking gum disease and hardening of the arteries. At first, there were observations that people with poor oral health were more prone to heart disease. More recently, scientists have found clear links between the total amount of periodontal bacteria in the mouth and blockages in the carotid artery. This study proves that at least some of the bacteria manage to escape that fate. This Science Update looks at the research, which leads to the findings presented and offers links to other sources for further inquiry.

  11. [Smoking cessation using nicotine gum].

    PubMed

    Schioldborg, P

    1990-04-10

    Smoking cessation in matched groups with (n = 54) versus without (n = 63) nicotine gum took place in order to test the gum with regard to abstinence rate and experienced value. In all, 71% quit smoking, 23% reduced consumption to half, while in 6% there was no change. The frequency was approximately even in the two groups. One month later, 79% of the quitters in the nicotine gum group still remained abstinent, compared with 54% in the control group (p less than 0.05). Six months later these frequencies were reduced to 34% and 20% respectively. Side effects were reported among one third of the users (aching of the jaw, sore throat), while two thirds found the gum useful. These persons found it hard to be without the gum, and that it reduced the craving for tobacco. In other words, it renders smoking cessation more certain. PMID:2333643

  12. Preparation and in vitro characterization of gellan based floating beads of acetohydroxamic acid for eradication of H. pylori.

    PubMed

    Rajinikanth, Parauvathanahalli Siddalingam; Mishra, Brahmeshwar

    2007-12-01

    Gellan based floating beads of acetohydroxamic acid (AHA) were prepared by the ionotropic gellation method to achieve controlled and sustained drug release for treatment of Helicobacter pylori infection. The prepared beads were evaluated for diameter, surface morphology and encapsulation efficiency. Formulation parameters like concentrations of gellan, chitosan, calcium carbonate and the drug influenced the in vitro drug release characteristics of beads. Drug and polymer interaction studies were carried out using differential scanning calorimetry. Chitosan coating increased encapsulation efficiency of the beads and reduced the initial burst release of the drug from the beads. Kinetic treatment of the drug release data revealed a matrix diffusion mechanism. Prepared floating beads showed good antimicrobial activity (in vitro H. pylori culture) as potent urease inhibitors. In conclusion, an oral dosage form of floating gellan beads containing AHA may form a useful stomach site specific drug delivery system for the treatment of H. pylori infection. PMID:18165186

  13. Do It: Chew that Gum!

    NSDL National Science Digital Library

    Dragonfly TV

    In this science experiment, kids learn that when they chew gum and spit it out, it weighs less than it did originally because the weight of the saliva added is less than the weight of the sugar swallowed.

  14. Nanomechanical Testing of Gum Metal

    Microsoft Academic Search

    E. A. Withey; J. Ye; A. M. Minor; S. Kuramoto; D. C. Chrzan; J. W. Morris

    2010-01-01

    Gum Metal” is a newly developed ?-Ti alloy that, in the cold-worked condition, has exceptional elastic elongation and high\\u000a strength. The available evidence suggests that Gum Metal does not yield until the applied stress approaches the ideal strength,\\u000a and then deforms by mechanisms that do not involve conventional crystal dislocations. To study its behavior, submicron-sized\\u000a pillars of solution-treated and cold-worked

  15. 'Radioactive' decay of chewing gum

    NSDL National Science Digital Library

    Kyle Nichols

    Student preparation for this assignment is the same as any other class. They are responsible to complete the reading before class. After I have introduced the concept of isotopic decay I have three student volunteers conduct the 'experiment'. One student is the time keeper while the other two students chew gum and weigh the gum at one minute intervals. The only instructions to the students are to chew consistently and to make sure they try to weigh a 'dry' piece of gum. The time keeper is responsible for making sure the gum chewers weigh the sample after each minute of chewing. I enter the data into a spread sheet as it is collected. That way I can discuss the data, explain the equations and ask questions. The entire experiment takes about 25 minutes to complete. After all of the data are collected, we determine half-lives through an iterative process by minimizing the RMS error. This also allows me to introduce error and one way to quantify it. This demonstration could be expanded into a component of a laboratory. Multiple students could chew the same gum to increase the sample size, the could chew different types of gum and measure a different decay constant, they could plot their own graphs, calculate their own decay constants and half-lives, and use a type of candy that does not follow the from exponential decay form. In this form students could form their own hypotheses and test them. There is no additional information that you need to know. I have included a spreadsheet of data from Fall 2007. You can use the same spreadsheet and just adjust for the data from your students. The only thing to keep in mind is that gum will not decay to almost 0 because there is a portion of the gum that will remain. We are only interested in the portion of the gum that does 'decay'. Therefore, I have included a 'mass correction' calculation based on the mass of the gum after the 10 minute mark.

  16. Treating Gum Disease Might Help Prostate Symptoms

    MedlinePLUS

    ... fullstory_152700.html Treating Gum Disease Might Help Prostate Symptoms: Study Periodontal problems linked to inflammation throughout ... Treating gum disease may help reduce symptoms of prostate inflammation, which can make urination difficult, a small ...

  17. 21 CFR 582.3336 - Gum guaiac.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Preservatives § 582.3336 Gum guaiac. (a) Product. Gum guaiac. (b) Tolerance. 0.1 percent (equivalent antioxidant activity 0.01 percent). (c) Limitations, restrictions, or explanation. This substance is generally...

  18. 21 CFR 582.3336 - Gum guaiac.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Preservatives § 582.3336 Gum guaiac. (a) Product. Gum guaiac. (b) Tolerance. 0.1 percent (equivalent antioxidant activity 0.01 percent). (c) Limitations, restrictions, or explanation. This substance is generally...

  19. 21 CFR 582.3336 - Gum guaiac.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Preservatives § 582.3336 Gum guaiac. (a) Product. Gum guaiac. (b) Tolerance. 0.1 percent (equivalent antioxidant activity 0.01 percent). (c) Limitations, restrictions, or explanation. This substance is generally...

  20. 21 CFR 582.3336 - Gum guaiac.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Preservatives § 582.3336 Gum guaiac. (a) Product. Gum guaiac. (b) Tolerance. 0.1 percent (equivalent antioxidant activity 0.01 percent). (c) Limitations, restrictions, or explanation. This substance is generally...

  1. 21 CFR 582.3336 - Gum guaiac.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Preservatives § 582.3336 Gum guaiac. (a) Product. Gum guaiac. (b) Tolerance. 0.1 percent (equivalent antioxidant activity 0.01 percent). (c) Limitations, restrictions, or explanation. This substance is generally...

  2. Periodontal (Gum) Disease Causes, Symptoms, and Treatments

    E-print Network

    Bandettini, Peter A.

    Periodontal (Gum) Disease Causes, Symptoms, and Treatments U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health #12;Periodontal (Gum) Disease If you have been told you have periodontal (gum) disease, you're not alone. Many adults in the U.S. currently have some form of the disease

  3. 21 CFR 573.1010 - Xanthan gum.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...6 2011-04-01 2011-04-01 false Xanthan gum. 573.1010 Section 573.1010 Food...ANIMALS Food Additive Listing § 573.1010 Xanthan gum. The food additive xanthan gum may be safely used in animal feed as...

  4. 21 CFR 573.1010 - Xanthan gum.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...6 2014-04-01 2014-04-01 false Xanthan gum. 573.1010 Section 573.1010 Food...ANIMALS Food Additive Listing § 573.1010 Xanthan gum. The food additive xanthan gum may be safely used in animal feed as...

  5. 21 CFR 573.1010 - Xanthan gum.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...6 2012-04-01 2012-04-01 false Xanthan gum. 573.1010 Section 573.1010 Food...ANIMALS Food Additive Listing § 573.1010 Xanthan gum. The food additive xanthan gum may be safely used in animal feed as...

  6. 21 CFR 573.1010 - Xanthan gum.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...6 2010-04-01 2010-04-01 false Xanthan gum. 573.1010 Section 573.1010 Food...ANIMALS Food Additive Listing § 573.1010 Xanthan gum. The food additive xanthan gum may be safely used in animal feed as...

  7. How Much Sugar Is in Bubble Gum?

    NSDL National Science Digital Library

    2014-09-18

    Some of the flavoring in bubble gum is due to the sugar or other sweetener it contains. As gum is chewed, the sugar dissolves and is swallowed. After a piece of gum loses its sweetness, it can be left to dry at room temperature and then the difference between its initial (unchewed) mass and its chewed mass can be used to calculate the percentage of sugar in the gum. This demonstration experiment is used to generate new questions about gums and their ingredients, and students can then design and execute new experiments based on their own questions.

  8. Preparation and characterization of antimicrobial wound dressings based on silver, gellan, PVA and borax.

    PubMed

    Cencetti, C; Bellini, D; Pavesio, A; Senigaglia, D; Passariello, C; Virga, A; Matricardi, P

    2012-10-15

    Silver-loaded dressings are designed to provide the same antimicrobial activity of topical silver, with the advantages of a sustained silver release and a reduced number of dressing changes. Moreover, such type of dressing must provide a moist environment, avoiding fiber shedding, dehydration and adherence to the wound site. Here we describe the preparation of a novel silver-loaded dressing based on a Gellan/Hyaff(®) (Ge-H) non woven, treated with a polyvinyl alcohol (PVA)/borax system capable to enhance the entrapment of silver in the dressing and to modulate its release. The new hydrophilic non woven dressings show enhanced water uptake capability and slow dehydration rates. A sustained silver release is also achieved. The antibacterial activity was confirmed on Staphylococcus aureus and Pseudomonas aeruginosa. PMID:22939352

  9. Brief Report: Gum Chewing Affects Standardized Math Scores in Adolescents

    ERIC Educational Resources Information Center

    Johnston, Craig A.; Tyler, Chermaine; Stansberry, Sandra A.; Moreno, Jennette P.; Foreyt, John P.

    2012-01-01

    Gum chewing has been shown to improve cognitive performance in adults; however, gum chewing has not been evaluated in children. This study examined the effects of gum chewing on standardized test scores and class grades of eighth grade math students. Math classes were randomized to a gum chewing (GC) condition that provided students with gum

  10. 21 CFR 184.1343 - Locust (carob) bean gum.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Locust (carob) bean gum. 184.1343 Section 184.1343...Substances Affirmed as GRAS § 184.1343 Locust (carob) bean gum. (a) Locust (carob) bean gum is primarily the macerated...

  11. Schultheiss Chewing gum and salivary hormones 1 Running head: CHEWING GUM AND SALIVARY HORMONES

    E-print Network

    Schultheiss, Oliver C.

    , International Journal of Psychophysiology Abstract: 116 words Body text: 2,347 words Please direct all, no gum) as well as in a saliva pool and water, either untreated or treated with chewing gum. Sugarless [4] #12;Schultheiss Chewing gum and salivary hormones 4 found this stimulant to be safe

  12. Effect of a glassy gellan/polydextrose matrix on the activity of ?-D-glucosidase.

    PubMed

    Chaudhary, Vinita; Small, Darryl M; Kasapis, Stefan

    2013-06-01

    An investigation of the ability of the enzyme ?-D-glucosidase to act on the substrate 4-nitrophenyl ?-D-glucopyranoside (pNPG) while embedded in glassy carbohydrate matrices (deacylated gellan with polydextrose and polydextrose alone) is presented. Physicochemical characterisation of the matrices was achieved using the techniques of modulated differential scanning calorimetry, small deformation dynamic oscillation on shear, Fourier transform infra-red spectroscopy, wide angle X-ray diffraction and scanning electron microscopy. A UV-vis spectrophotometric procedure was adapted for the analysis of the activity of ?-D-glucosidase in hydrolysing pNPG in the condensed carbohydrate systems. In order to derive a relationship between the structural properties of the matrix and the enzymatic activity, mechanical spectra were recorded using the combined framework of the Williams, Landel and Ferry equation with the time-temperature superposition principle. Theoretical modelling and experimental observations strongly argue for a pronounced effect of the gelling polysaccharide/co-solute mixture on enzymatic activity near the mechanical Tg of the matrix. PMID:23618284

  13. Properties and applications of xanthan gum

    Microsoft Academic Search

    Barbara Katzbauer

    1998-01-01

    Xanthan gum is a natural high molecular weight polysaccharide produced by a fermentation process. Due to its exceptional rheological properties it is a very effective stabilizer for water-based systems. Its numerous areas of application cover a broad range, from the food industry to oil drilling. Typical food applications of xanthan gum are salad dressings, sauces, gravies, dairy products, desserts, low-calorie

  14. Nicotine Gum and Behavioral Treatment: A Placebo Controlled Trial.

    ERIC Educational Resources Information Center

    Hall, Sharon M.; And Others

    1987-01-01

    Assigned 139 subjects to intensive behavioral or to low-contact smoking treatment and to 2-milligram nicotine gum or to placebo gum in a 2x2 factorial design. Nicotine gum produced higher abstinence rates than did placebo. Subjects receiving low-contact condition plus nicotine gum had excellent abstinence rates at both 26 weeks and 52 weeks.…

  15. Effect of gum chewing on plaque accumulation.

    PubMed

    Hoerman, K C; Gasior, E J; Zibell, S E; Record, D; Flowerdew, G

    1990-01-01

    The purpose of this investigation was to test the effect of chewing gum sweetened with either sorbitol (LG) or sucrose (SG) on the growth of plaque on tooth enamel surfaces. Nineteen dental students, in a balanced crossover design, chewed the two gums for 5 days without normal oral hygiene practices. The control treatment was a 5-day non-chewing (NG) phase. A period of 9 days was allowed for normal hygiene between test phases. The chewing regimen required 20 minutes of use of one stick of chewing gum immediately after meals or snacks. The average number of sticks chewed was 3.8/day. Pre- and post-treatment plaque scores were recorded by two examiners using a Modified Navy Plaque Index (PLI) from 0 to 9 along each of four surfaces to assess six Ramfjord teeth. Pre-treatment mean PLI scores for the 3 test treatments were, NG = 2.0, LG = 1.9 and SG = 1.9. Post-treatment mean PLI scores were, NG = 3.6, LG = 3.3 and SG = 3.3. ANOVA of pre- and post-treatment scores revealed no significant differences between treatments. Post-treatment scores of the 2 chewing gums were then pooled, independent of sweetener. ANOVA of these data revealed chewing gum (LG + SG = 3.3) to cause significantly less plaque accumulation than no gum (NG = 3.6). In a no oral hygiene environment, plaque accumulation during use of sorbitol chewing gum or sucrose chewing gum was statistically the same. However, chewing gum, irrespective of sweetener, caused significantly less plaque accumulation than no chewing. PMID:2133390

  16. Chewing gum and context-dependent memory: the independent roles of chewing gum and mint flavour.

    PubMed

    Johnson, Andrew J; Miles, Christopher

    2008-05-01

    Two experiments independently investigated the basis of the chewing gum induced context-dependent memory effect. At learning and/or recall, participants either chewed flavourless gum (Experiment 1) or received mint-flavoured strips (Experiment 2). No context-dependent memory effect was found with either flavourless gum or mint-flavoured strips, indicating that independently the contexts were insufficiently salient to induce the effect. This is found despite participants' subjective ratings indicating a perceived change in state following administration of flavourless gum or mint-flavoured strips. Additionally, some preliminary evidence for a non-additive facilitative effect of receiving gum or flavour at either learning and/or recall is reported. The findings raise further concerns regarding the robustness of the previously reported context-dependent memory effect with chewing gum. PMID:17651533

  17. Scientific Method Lab Using Bubble Gum

    NSDL National Science Digital Library

    This activity is a lab investigation where students gather data which compares 2 types of bubble gum, while learning to use the scientific method to collect qualitative and quantitative data using SI units.

  18. 21 CFR 184.1333 - Gum ghatti.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...ghatti (Indian gum) is an exudate from wounds in the bark of Anogeissus latifolia, a large tree found in the dry deciduous forests of India and Ceylon. (b) The ingredient complies with the following specifications: (1) Viscosity of...

  19. 21 CFR 184.1333 - Gum ghatti.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...ghatti (Indian gum) is an exudate from wounds in the bark of Anogeissus latifolia, a large tree found in the dry deciduous forests of India and Ceylon. (b) The ingredient complies with the following specifications: (1) Viscosity of...

  20. 21 CFR 184.1333 - Gum ghatti.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...ghatti (Indian gum) is an exudate from wounds in the bark of Anogeissus latifolia, a large tree found in the dry deciduous forests of India and Ceylon. (b) The ingredient complies with the following specifications: (1) Viscosity of...

  1. 21 CFR 184.1333 - Gum ghatti.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...ghatti (Indian gum) is an exudate from wounds in the bark of Anogeissus latifolia, a large tree found in the dry deciduous forests of India and Ceylon. (b) The ingredient complies with the following specifications: (1) Viscosity of...

  2. 21 CFR 184.1333 - Gum ghatti.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...ghatti (Indian gum) is an exudate from wounds in the bark of Anogeissus latifolia, a large tree found in the dry deciduous forests of India and Ceylon. (b) The ingredient complies with the following specifications: (1) Viscosity of...

  3. Influences on Gum Feeding in Primates

    Microsoft Academic Search

    Andrew C. Smith

    \\u000a This chapter reviews the factors that may affect patterns of gum ­feeding by primates. These are then examined for mixed-species\\u000a troops of saddleback (Saguinus fuscicollis) and mustached (Saguinus mystax) tamarins. An important distinction is made between gums produced by tree trunks and branches as a result of damage and those\\u000a produced by seed pods as part of a dispersal strategy

  4. Fractionation of Mastic Gum in Relation to Antimicrobial Activity

    PubMed Central

    Sharifi, Mohammad Sharif; Hazell, Stuart Loyd

    2009-01-01

    Mastic gum is a viscous light-green liquid obtained from the bark of Pistacia lentiscus var. chia. which belongs to the Anacardiaceae family. The gum has been fractionated to investigate the antimicrobial activity of the whole gum and its fractions against various strains of Helicobacter pylori. The polymeric gum fraction was separated from the essential oil and the resin (trunk exudates without essential oil) to assess and compare the anti-H. pylori activity of the polymer fraction against lower molecular weight fractions, the gum itself and masticated gum. The polymer fraction was also oxidized and assessed for antimicrobial activity.

  5. Long-Slit Spectrophotometry of the H II Regions Gum 38a and Gum 38b

    NASA Astrophysics Data System (ADS)

    Girardi, Léo; Bica, Eduardo; Pastoriza, Miriani G.; Winge, Cláudia

    1997-09-01

    We present new long-slit spectrophotometric observations in the range 3700-7200 Å of the H II regions Gum 38a and Gum 38b (RCW 57). We study the spatial distribution of reddening and excitation throughout the complex by means of emission-line intensities. From the strong reddening difference, we confirm that Gum 38a and Gum 38b are two individual complexes, the former being in the foreground. We derive chemical abundances in both nebulae, the results of which are similar to those of the Orion Nebula. This is consistent with the fact that the three nebulae are located at similar Galactocentric distances. We also discuss the general ionization structure of the complexes based on the spectral properties of several filaments and diffuse emission around the central bright knots of Gum 38a and beyond. In particular, we found an interesting filament with strong [O I] ??6300, 6364 lines.

  6. 21 CFR 582.7343 - Locust bean gum.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Stabilizers § 582.7343 Locust bean gum. (a) Product. Locust (carob) bean gum. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good...

  7. 21 CFR 582.7343 - Locust bean gum.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Stabilizers § 582.7343 Locust bean gum. (a) Product. Locust (carob) bean gum. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good...

  8. Medicated chewing gum, a novel drug delivery system

    PubMed Central

    Aslani, Abolfazl; Rostami, Farnaz

    2015-01-01

    New formulations and technologies have been developed through oral drug delivery systems’ researches. Such researches display significance of oral route amongst patients. We’ve reviewed all the features associated with medicated chewing gum as a modern drug delivery by introducing the history, advantages and disadvantages, methods of manufacturing, composition differences, evaluation tests and examples of varieties of medicated chewing gums. Acceptance of medicated chewing gum has been augmented through years. The advantages and therapeutic benefits of chewing gum support its development as we can see new formulations with new drugs contained have been produced from past and are going to find a place in market by formulation of new medicated chewing gums. Potential applications of medicated chewing gums are highly widespread as they will be recognized in future. Nowadays standards for qualifying chewing gums are the same as tablets. Patient-centered studies include medicated chewing gums as a delivery system too which creates compliance for patients.

  9. Manilkara zapota (Linn.) Seeds: A Potential Source of Natural Gum

    PubMed Central

    Singh, Sudarshan; Bothara, Sunil B.

    2014-01-01

    Mucilage isolated from seeds of Manilkara zapota (Linn.) P. Royen syn. is a plant growing naturally in the forests of India. This mucilage is yet to be commercially exploited, and characterized as polymer. Various physicochemical methods like particle size analysis, scanning electron microscopy, thermal analysis, gel permeation chromatography, X-ray diffraction spectrometry, zeta potential, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy have been employed to characterize this gum in the present study. Particle size analyses suggest that mucilage has particle size in nanometer. Scanning electron microscopy analysis suggests that the mucilage has irregular particle size. The glass transition temperature of the gum was observed to be 138°C and 136°C by differential scanning calorimetry and differential thermal analysis, respectively. The thermogravimetric analysis suggested that mucilage had good thermal stability. The average molecular weight of mucilage was determined to be 379180, by gel permeation chromatography, while the viscosity of mucilage was observed to be 219.1 cP. The X-ray diffraction spectrometry pattern of the mucilage indicates a completely amorphous structure. Elemental analysis of the gum revealed the contents of carbon, hydrogen, nitrogen, and sulfur to be 80.9 (%), 10.1 (%), 1.58 (%), and 512 (mg/kg), respectively. Mucilage had specific content of calcium, magnesium, potassium, lower concentrations of aluminum, cadmium, cobalt, lead, and nickel. The major functional groups identified from FT-IR spectrum include 3441?cm?1 (–OH), 1660?cm?1 (Alkenyl C–H & C=C Stretch), 1632?cm?1 (–COO–), 1414?cm?1 (–COO–), and 1219?cm?1 (–CH3CO). Analysis of mucilage by paper chromatography and 1D NMR, indicated the presence of rhamnose, xylose, arabinose, mannose, and fructose. PMID:24729907

  10. Manilkara zapota (Linn.) Seeds: A Potential Source of Natural Gum.

    PubMed

    Singh, Sudarshan; Bothara, Sunil B

    2014-01-01

    Mucilage isolated from seeds of Manilkara zapota (Linn.) P. Royen syn. is a plant growing naturally in the forests of India. This mucilage is yet to be commercially exploited, and characterized as polymer. Various physicochemical methods like particle size analysis, scanning electron microscopy, thermal analysis, gel permeation chromatography, X-ray diffraction spectrometry, zeta potential, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy have been employed to characterize this gum in the present study. Particle size analyses suggest that mucilage has particle size in nanometer. Scanning electron microscopy analysis suggests that the mucilage has irregular particle size. The glass transition temperature of the gum was observed to be 138°C and 136°C by differential scanning calorimetry and differential thermal analysis, respectively. The thermogravimetric analysis suggested that mucilage had good thermal stability. The average molecular weight of mucilage was determined to be 379180, by gel permeation chromatography, while the viscosity of mucilage was observed to be 219.1 cP. The X-ray diffraction spectrometry pattern of the mucilage indicates a completely amorphous structure. Elemental analysis of the gum revealed the contents of carbon, hydrogen, nitrogen, and sulfur to be 80.9 (%), 10.1 (%), 1.58 (%), and 512 (mg/kg), respectively. Mucilage had specific content of calcium, magnesium, potassium, lower concentrations of aluminum, cadmium, cobalt, lead, and nickel. The major functional groups identified from FT-IR spectrum include 3441?cm(-1) (-OH), 1660?cm(-1) (Alkenyl C-H & C=C Stretch), 1632?cm(-1) (-COO-), 1414?cm(-1) (-COO-), and 1219?cm(-1) (-CH3CO). Analysis of mucilage by paper chromatography and 1D NMR, indicated the presence of rhamnose, xylose, arabinose, mannose, and fructose. PMID:24729907

  11. Kinetics of gum deposition during storage of diesel fuel

    Microsoft Academic Search

    I. N. Grishina; I. M. Kolesnikov; S. T. Bashkatova; A. Marvan

    2007-01-01

    The kinetic features of the deposition of gums formed during long-term storage of diesel fuel in tanks were studied. A kinetic\\u000a equation for the calculation of the gum formation rate was proposed. The rate constant and the order of the reaction were\\u000a calculated. It was found that the gum formation process is accompanied by self-retardation and the gums produced inhibit

  12. Sugar substitutes, chewing gum and dental caries--a review.

    PubMed

    Edgar, W M

    1998-01-10

    The prevalent use of chewing gum has prompted interest in its dental effects. Important defining aspects are the ability to use sugar substitutes in gum manufacture and the prolonged stimulation of a protective flow of saliva. The main sugar substitutes used are sorbitol and xylitol. Because it is not fermented by oral bacteria, xylitol is considered to be non-cariogenic, and while sorbitol in solution can be fermented slowly by mutants streptococci, chewing sorbitol-sweetened gum does not cause a fall in plaque pH. Effects of chewing sugar-free gum on the ability of plaque to form acid from sucrose are equivocal, although the tendency is for the plaque acidogenicity to be reduced with the use of xylitol gum for 2-3 weeks, due to its inhibitory effects on mutants streptococci. Gum-chewing also stimulates a protective salivary flow when used after an acidogenic stimulus, and may enhance salivary function, especially in subjects with low flow rates. Sorbitol and xylitol gums have similar beneficial effects in promoting enamel remineralisation in short-term in-situ experiments. Clinical trials indicate that xylitol gum has a useful anticaries role, superior to the effects of sorbitol gum. In conclusion, both sorbitol and xylitol chewing gums are non-cariogenic in contrast to sugared gum, and exhibit beneficial anticaries properties through salivary stimulation. In addition, xylitol's antibacterial properties seem likely to lead to caries reductions superior to the more modest reductions with sorbitol gum. PMID:9479811

  13. Oral bolus kneading and shaping measured with chewing gum

    Microsoft Academic Search

    Birgitta Liedberg; Bengt Öwall

    1995-01-01

    A masticatory test using two-colored chewing gum is presented and analyzed. Two separate parameters of chewing were studied on the same chewing gum bolus after 10 strokes of oral preparation, color mixing, and bolus shaping. The two parameters were evaluated in indices 1–5. A test series should preferably contain three chewing gums, and color mixing can be evaluated on six

  14. Current Evidence on the Anticancer Potential of Chios Mastic Gum

    Microsoft Academic Search

    Constantinos Giaginis; Stamatios Theocharis

    2011-01-01

    Chios mastic gum derived from the plant Pistacia lentiscus L. variation chia has been shown to exert beneficial effects on a wide range of human disorders. The most comprehensive data so far have indicated that mastic gum provides protection against gastrointestinal malfunctions and bacterial infections. Substantial evidence has also suggested that mastic gum exhibits hepatoprotective and cardioprotective, antiinflammatory\\/antioxidant, and antiatherogenic

  15. Biobased alternatives to guar gum as tackifiers for hydromulch

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Guar gum, obtained from guar [Cyamopsis tetragonoloba (L.) Taub.] seeds, is currently the principal gum used as a tackifier (binder) for hydraulically-applied mulches (hydromulches) used in erosion control. The oil industry’s increased use of guar gum in hydraulic fracturing together with lower glo...

  16. 78 FR 43226 - Xanthan Gum From Austria and China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ...Nos. 731-TA-1202-03 (Final)] Xanthan Gum From Austria and China Determinations...injury by reason of imports from Austria of xanthan gum provided for in subheading 3913...injury by reason of imports from China of xanthan gum provided for in subheading...

  17. Xanthan gum: production, recovery, and properties

    Microsoft Academic Search

    F Garc??a-Ochoa; V. e. Santos; J. a. Casas; E. Gomez

    2000-01-01

    Xanthan gum is a microbial polysaccharide of great commercial significance. This review focuses on various aspects of xanthan production, including the producing organism Xanthomonas campestris, the kinetics of growth and production, the downstream recovery of the polysaccharide, and the solution properties of xanthan.

  18. Effect of GutsyGum(tm), A Novel Gum, on Subjective Ratings of Gastro Esophageal Reflux Following A Refluxogenic Meal.

    PubMed

    Brown, Rachel; Sam, Cecilia H Y; Green, Tim; Wood, Simon

    2015-06-01

    Chewing gum alleviates symptoms of gastro-esophageal reflux (GER) following a refluxogenic meal. GutsyGum(tm), a chewing gum developed to alleviate the symptoms of GER contains calcium carbonate, with a proprietary blend of licorice extract, papain, and apple cider vinegar (GiGs®). The efficacy of GutsyGum(tm) was determined in alleviating the symptoms of GER after a refluxogenic meal compared to placebo gum. This double-blind, placebo-controlled-crossover trial with a one-week washout between treatments had 24 participants with a history of GER consume a refluxogenic meal and then chew GutsyGum(tm) or placebo gum. Participants completed GER symptom questionnaires, consisting of symptom based 10 cm Visual Analogue Scales, immediately following the meal and then at regular intervals out to four hours postmeal. Adjusted mean ± SEM heartburn score (15-min postmeal to 240 min) was significantly lower in GutsyGum(tm) than in placebo gum treatment (0.81 ± 0.20 vs. 1.45 ± 0.20 cm; p = 0.034). Mean acid reflux score was significantly lower in GutsyGum(tm) than in placebo treatment (0.72 ± 0.19 vs. 1.46 ± 0.19 cm; p = 0.013). There were no significant differences for any of the secondary outcomes. However, pain approached significance with less pain reported in GutsyGum(tm) versus placebo treatment (0.4 ± 0.2 vs. 0.9 ± 0.2 cm; p = 0.081). Although nausea (p = 0.114) and belching (p = 0.154) were lower following GutsyGum(tm), the difference was not statistically significant. GutsyGum(tm) is more effective than a placebo gum in alleviating primary symptoms of heartburn and acid reflux (Clinical Trial Registration: ACTRN12612000973819). PMID:25144853

  19. Preparation and evaluation of release characteristics of 3TabGum, a novel chewing device

    Microsoft Academic Search

    L. Maggi; L. Segale; S. Conti; E. Ochoa Machiste; A. Salini; U. Conte

    2005-01-01

    A new chewing gum device in the form of a three layers tablet (3TabGum) has been developed. The new drug delivery system is obtained, at room temperature, by direct compression using conventional pharmaceutical equipment. Basically, the resulting chewing gum tablets comprise a gum core combined with two protective antiadherent external layers, which prevent gum adhesion to the punches of the

  20. Antibacterial activity of biogenic silver nanoparticles synthesized with gum ghatti and gum olibanum: a comparative study.

    PubMed

    Kora, Aruna Jyothi; Sashidhar, Rao Beedu

    2015-02-01

    Presently, silver nanoparticles produced by biological methods have received considerable significance owing to the natural abundance of renewable, cost-effective and biodegradable materials, thus implementing the green chemistry principles. Compared with the nanoparticles synthesized using chemical methods, most biogenic silver nanoparticles are protein capped, which imparts stability and biocompatibility, and enhanced antibacterial activity. In this study, we compared the antibacterial effect of two biogenic silver nanoparticles produced with natural plant gums: gum ghatti and gum olibanum against Gram-negative and Gram-positive bacteria. Bacterial interaction with nanoparticles was probed both in planktonic and biofilm modes of growth; employing solid agar and liquid broth assays for inhibition zone, antibiofilm activity, inhibition of growth kinetics, leakage of intracellular contents, membrane permeabilization and reactive oxygen species production. In addition, cytotoxicity of the biogenic nanoparticles was evaluated in HeLa cells, a human carcinoma cell line. Antibacterial activity and cytotoxicity of the silver nanoparticles synthesized with gum ghatti (Ag NP-GT) was greater than that produced with gum olibanum (Ag NP-OB). This could be attributed to the smaller size (5.7?nm), monodispersity and zeta potential of the Ag NP-GT. The study suggests that Ag NP-GT can be employed as a cytotoxic bactericidal agent, whereas Ag NP-OB (7.5?nm) as a biocompatible bactericidal agent. PMID:25138141

  1. Direct photography of the Gum Nebula

    NASA Technical Reports Server (NTRS)

    Brandt, J. C.; Roosen, R. G.; Thompson, J.; Ludden, D. J.

    1976-01-01

    The paper discusses a series of wide-angle photographs taken of the Gum Nebula in the traditional region including H-alpha with the aid of a 40-cm and an 80-cm lens in both the red and the green. The photographs support the large dimensions (75 deg in galactic longitude by 40 deg in galactic latitude) of the Gum Nebula suggested earlier, and the appearance is consistent with an origin due to photons from a supernova outburst. The relatively high-density gas has cooled and is visible on the red plates. The low-density gas has remained at a high temperature and may be visible as diffuse emission on the green plates.

  2. 77 FR 65361 - Xanthan Gum From Austria and the People's Republic of China: Postponement of Preliminary...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-26

    ...Administration [A-433-811, A-570-985] Xanthan Gum From Austria and the People's Republic...of antidumping duty investigations of xanthan gum from Austria and the People's Republic...1\\ See Xanthan Gum From Austria and the People's...

  3. Antiectoparasitic activity of the gum resin, gum haggar, from the East African plant, Commiphora holtziana.

    PubMed

    Birkett, Michael A; Abassi, Sate Al; Kröber, Thomas; Chamberlain, Keith; Hooper, Antony M; Guerin, Patrick M; Pettersson, Jan; Pickett, John A; Slade, Robin; Wadhams, Lester J

    2008-05-01

    The mechanism of ixodid tick (Acari: Ixodidae) repellency by gum haggar, a resin produced by Commiphora holtziana (Burseraceae), was investigated by evaluating activity against the cattle tick, Boophilus microplus. In an arena bioassay, a hexane extract of the resin of C. holtziana exhibited a repellent effect lasting up to 5h. The hydrocarbon fraction of the resin extract was shown to account for the repellent activity, and was analysed by coupled gas chromatography-mass spectrometry (GC-MS). Major sesquiterpene hydrocarbons were tentatively identified as germacrene-D, delta-elemene and beta-bourbonene. The identity and stereochemistry of the former compound was confirmed as the (+)-isomer by peak enhancement using enantioselective GC, whereas the latter 2 compounds, which are most likely degradation products of germacrene-type precursors, were identified through isolation by preparative gas chromatography followed by microprobe-NMR spectroscopy. GC comparison of gum haggar with another resin, C. myrrha, which was inactive in the tick bioassay, showed that the latter contained much lower levels of these hydrocarbons. To assess the suitability of the gum haggar resin as a general acarine repellent, further tests were made on a major acarine pest of European and US animal husbandry systems, the red poultry mite, Dermanyssus gallinae (Acari: Dermanyssidae). Gum haggar extract, and the isolated hydrocarbon fraction, showed strong repellent effects in an olfactometer assay, and again gum myrrh showed no effect. These findings provide a scientific basis for the observed anti-tick properties of gum haggar, and demonstrate the potential for its development as a general acarine repellent for use in animal husbandry systems. PMID:18402993

  4. Ask a Periodontist (Frequently Asked Questions about Gum Disease)

    MedlinePLUS

    ... Gum Disease Regenerative Procedures Dental Crown Lengthening Procedure Dental Implants Single Tooth Implants Multiple Tooth Implants Full Mouth Dental Implants Sinus Augmentation Ridge Modification Periodontal Pocket Reduction Procedures ...

  5. Guar gum: processing, properties and food applications-A Review.

    PubMed

    Mudgil, Deepak; Barak, Sheweta; Khatkar, Bhupendar Singh

    2014-03-01

    Guar gum is a novel agrochemical processed from endosperm of cluster bean. It is largely used in the form of guar gum powder as an additive in food, pharmaceuticals, paper, textile, explosive, oil well drilling and cosmetics industry. Industrial applications of guar gum are possible because of its ability to form hydrogen bonding with water molecule. Thus, it is chiefly used as thickener and stabilizer. It is also beneficial in the control of many health problems like diabetes, bowel movements, heart disease and colon cancer. This article focuses on production, processing, composition, properties, food applications and health benefits of guar gum. PMID:24587515

  6. When to feed on gums: Temporal patterns of gummivory in wild tamarins,Saguinus mystaxand Saguinus fuscicollis(Callitrichinae)

    Microsoft Academic Search

    Eckhard W. Heymann; Andrew C. Smith

    1999-01-01

    This study examines the temporal patterning of gum feeding in two species of sympatric tamarin monkeys, Saguinus mystax and Saguinus fuscicollis, during the diurnal activity period. The number and duration of visits to gum sources and number of gum feeding records are used as parameters to analyze the gum feeding itinerary. Both visits to gum sources and gum feeding records

  7. Effect of gums on the rheological characteristics and microstructure of acid-induced SPI-gum mixed gels.

    PubMed

    Chang, Yuan-Yuan; Li, Dong; Wang, Li-Jun; Bi, Chong-Hao; Adhikari, Benu

    2014-08-01

    The effect of addition of xanthan gum (XG) and guar gum (GG) on the rheological properties and microstructure of glucono-?-lactone induced soy protein isolate (SPI)-XG gels and SPI-GG gels was investigated using steady and dynamic rheological tests, creep-recovery and confocal laser scanning microscopy (CLSM). Results showed that the apparent viscosity of SPI-gum (XG, GG) mixed solutions increased with the increase in the gum (XG, GG) concentration. The storage (G') and loss (G?) moduli of SPI-gum (XG, GG) mixed gels increased in the presence and increase in the gum (XG, GG) concentration. The Burger's model fitted the creep recovery data well (R(2)>0.919) and showed that both the instantaneous and equilibrium (retarded) elastic components of this model increased with the increase in SPI and gum concentrations. The proportion occupied by gum in mixed gels was found to increase with the increase in the concentration of gums which increased the density of protein aggregates in the mixed gels. PMID:24751263

  8. Neem gum as a binder in a formulated paracetamol tablet with reference to Acacia gum BP.

    PubMed

    Ogunjimi, Abayomi Tolulope; Alebiowu, Gbenga

    2014-04-01

    This study determined the physical, compressional, and binding properties of neem gum (NMG) obtained from the trunk of Azadirachta indica (A Juss) in a paracetamol tablet formulation in comparison with official Acacia gum BP (ACA). The physical and flow properties were evaluated using density parameters: porosity, Carr's index, Hausner's ratio, and flow rate. Compressional properties were analyzed using Heckel and Kawakita equations. The tensile strength, brittle fracture index, and crushing strength-friability/disintegration time ratio were used to evaluate the mechanical properties of paracetamol tablets while the drug release properties of the tablets were assessed using disintegration time and dissolution times. Tablet formulations containing NMG exhibited faster onset and higher amount of plastic deformation during compression than those containing ACA. Neem gum produced paracetamol tablets with lower mechanical strength; however, the tendency of the tablets to cap or laminate was lower when compared to those containing ACA. Inclusion of NMG improved the balance between binding and disintegration properties of paracetamol tablets produced than those containing ACA. Neem gum produced paracetamol tablets with lower disintegration and dissolution times than those containing ACA. PMID:24500339

  9. Marketing Chewing Gum: A Case Study of a Cypriot Company

    Microsoft Academic Search

    Evangelia K. Blery; Loukas Antoniades

    2010-01-01

    The purpose of this article is to examine the issues related to the chewing gum marketing practices employed by a Cypriot company importing gum. Thus, the product, its target market, and competition are examined, a SWOT analysis is performed and the marketing mix is presented. Then the results are compared with the international market.The case study method was employed to

  10. 21 CFR 172.615 - Chewing gum base.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...gum or wood rosin Having an acid number of 6-16, a minimum...with § 172.890. Stearic acid Complying with § 172.860...?pinene, and/or dipentene; acid value less than 5, saponification...of this section, chewing gum base may also include substances...

  11. 21 CFR 172.615 - Chewing gum base.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...gum or wood rosin Having an acid number of 6-16, a minimum...with § 172.890. Stearic acid Complying with § 172.860...?pinene, and/or dipentene; acid value less than 5, saponification...of this section, chewing gum base may also include substances...

  12. 21 CFR 172.615 - Chewing gum base.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...gum or wood rosin Having an acid number of 6-16, a minimum...with § 172.890. Stearic acid Complying with § 172.860...?pinene, and/or dipentene; acid value less than 5, saponification...of this section, chewing gum base may also include substances...

  13. Impact of welan gum on tricalcium aluminate-gypsum hydration

    SciTech Connect

    Ma Lei, E-mail: malei198713@163.com; Zhao Qinglin, E-mail: zhaoqinglin@whut.edu.cn; Yao Chukang; Zhou Mingkai

    2012-02-15

    The retarding effect of welan gum on tricalcium aluminate-gypsum hydration, as a partial system of ordinary Portland cement (OPC) hydration, was investigated with several methods. The tricalcium aluminate-gypsum hydration behavior in the presence or absence of welan gum was researched by field emission gun scanning electron microscopy, X-ray diffraction and zeta potential analysis. Meanwhile, we studied the surface electrochemical properties and adsorption characteristics of welan gum by utilizing a zeta potential analyzer and UV-VIS absorption spectrophotometer. By adding welan gum, the morphology change of ettringite and retardation of hydration stages in tricalcium aluminate-gypsum system was observed. Moreover, we detected the adsorption behavior and zeta potential inversion of tricalcium aluminate and ettringite, as well as a rapid decrease in the zeta potential of tricalcium aluminate-gypsum system. The reduction on nucleation rate of ettringite and hydration activity of C{sub 3}A was also demonstrated. Thus, through the adsorption effect, welan gum induces a retarding behavior in tricalcium aluminate-gypsum hydration. Highlights: Black-Right-Pointing-Pointer Adsorption characteristics of welan gum on C{sub 3}A and ettringite have been studied. Black-Right-Pointing-Pointer C{sub 3}A-gypsum hydration behavior and the hydration products are examined in L/S = 3. Black-Right-Pointing-Pointer Welan gum retards the process of C{sub 3}A-gypsum hydration. Black-Right-Pointing-Pointer The addition of welan gum changes the nucleation growth of ettringite.

  14. Pasting and rheological properties of native and anionic tapioca starches as modified by guar gum and xanthan gum

    Microsoft Academic Search

    Montri Chaisawang; Manop Suphantharika

    2006-01-01

    Effects of guar and xanthan gums on pasting and rheological properties of native and anionic tapioca starches were studied by using a Rapid Visco-Analyzer (RVA), a differential scanning calorimeter (DSC), a scanning electron microscope (SEM), and a rheometer. Results of RVA measurement indicated that addition of gums increased peak, breakdown, and final viscosities of native tapioca starch. This effect was

  15. Dodecenylsuccinic anhydride derivatives of gum karaya (Sterculia urens): preparation, characterization, and their antibacterial properties.

    PubMed

    Padil, Vinod Vellora Thekkae; Senan, Chandra; ?erník, Miroslav

    2015-04-15

    Esterifications of the tree-based gum, gum karaya (GK), using dodecenylsuccinic anhydride (DDSA) were carried out in aqueous solutions. GK was deacetylated using alkali treatment to obtain deacetylated gum karaya (DGK). The DGK and its DDSA derivative were characterized using gel permeation chromatography/multiangle laser light scattering (GPC/MALLS), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), proton nuclear magnetic resonance spectroscopy ((1)H NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) analysis, and rheological studies. The degree of substitution was found to be 10.25% for DGK using (1)H NMR spectroscopy. The critical aggregation concentration of DDSA-DGK was determined using dye solubilization and surface tension methods. The antibacterial activity of the DDSA-DGK derivative was then investigated against Gram-negative Escherichia coli and Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus. The DDSA-DGK derivative has the potential for use as a stabilizing agent in food and nonfood applications. It can also be developed as an antibacterial agent. PMID:25797306

  16. Carboxymethylation of Cassia angustifolia seed gum: synthesis and rheological study.

    PubMed

    Rajput, Gaurav; Pandey, I P; Joshi, Gyanesh

    2015-03-01

    The seeds of Cassia angustifolia are a rich source of galactomannan gum. The seed gums possess a wide variety of industrial applications. To utilize C. angustifolia seed gum for broader industrial applications, the carboxymethyl-Cassia angustifolia seed gum (CM-CAG) was synthesized. The gum was etherified with sodium monochloroacetate (SMCA) in a methanol-water system in presence of alkali (NaOH) at different reaction conditions. The variables studied includes alkali concentration, SMCA concentration, methanol:water ratio, liquor:gum ratio, reaction temperature and time. The extent of carboxymethylation was determined as degree of substitution (DS). The optimum conditions for preparing CM-CAG (DS=0.474) comprised 0.100 mol of NaOH, 0.05 mol of SMCA, 80% of methanol:water ratio (as % methanol) and liquor:gum ratio (v/w) of 10:1 at 75 °C for 60 min using 0.03 mol (as AGU) of CAG. Rheological studies showed CM-CAG to exhibit non-Newtonian pseudoplastic behaviour, relatively high viscosity, cold water solubility and solution stability. PMID:25498663

  17. Bactericidal activity of Pistacia lentiscus mastic gum against Helicobacter pylori.

    PubMed

    Marone, P; Bono, L; Leone, E; Bona, S; Carretto, E; Perversi, L

    2001-12-01

    In this study we evaluated the antibacterial activity of mastic gum, a resin obtained from the Pistacia lentiscus tree, against clinical isolates of Helicobacter pylori. The minimal bactericidal concentrations (MBCs) were obtained by a microdilution assay. Mastic gum killed 50% of the strains tested at a concentration of 125 microg/ml and 90% at a concentration of 500 microg/ml. The influence of sub-MBCs of mastic gum on the morphologies of H. pylori was evaluated by transmission electron microscopy. The lentiscus resin induced blebbing, morphological abnormalities and cellular fragmentation in H. pylori cells. PMID:11806621

  18. Production of xanthan gum from a chemically defined medium introduction

    SciTech Connect

    Weisrock, W.P.; Klein, H.S.

    1983-02-22

    Heteropolysaccharides produced by the action of Xanthomonas bacteria on carbohydrate media have a potential application as film forming agents, as thickeners in oil field drilling fluids and fracturing liquids and as emulsifying, stabilizing, and sizing agents. Heteropolysaccharides, particularly, xanthan gum, have a significant potential as mobility control agents in micellar polymer flooding. Xanthan gum has excellent viscosifying properties at low concentration, is resistant to shear degradation and exhibits only minimal losses in viscosity as a function of temperature, pH, and ionic strength. For these reasons, xanthan gum is an attractive alternative to synthetic polyacrylamides for enhanced oil recovery operations. 15 claims.

  19. Evaluation of a Treatment Approach Combining Nicotine Gum with Self-Guided Behavioral Treatments for Smoking Relapse Prevention.

    ERIC Educational Resources Information Center

    Killen, Joel D.; And Others

    1990-01-01

    Randomly assigned 1,218 smokers to cells in 4 (nicotine gum delivered ad lib, fixed regimen nicotine gum, placebo gum, no gum) x 3 (self-selected relapse prevention modules, randomly administered modules, no modules) design. Subjects receiving nicotine gum were more likely to be abstinent at 2- and 6-month followups. Fixed regimen accounted for…

  20. Antimicrobial effect of mastic gum methanolic extract against Porphyromonas gingivalis.

    PubMed

    Sterer, Nir

    2006-01-01

    The antimicrobial effect of mastic gum, an ancient remedy for oral malodor, against Porphyromonas gingivalis, a known odorogenic periopathogenic oral bacterium, was tested using the agar diffusion test. Paper discs impregnated with mastic gum methanolic extract (MME) [0.5-4% (wt/vol)] produced inhibition zones of 10.5-13.7 mm, respectively, without showing signs of hemolysis, whereas chlorhexidine (0.2%)-impregnated discs, which showed greater inhibition (33.5 mm), also produced large and distinctive hemolytic zones (17 mm). Further analysis of the antimicrobial traits of MME revealed a logarithmic ratio between inhibition zone diameter and MME concentration (r = .99), indicating limited water solubility of this material. These results suggest that mastic gum may be used as a potential nontoxic local agent in treating oral malodor and gum disease. PMID:16822220

  1. Preformulation studies on grewia gum as a formulation excipient

    Microsoft Academic Search

    Elijah I. NepBarbara; Barbara R. Conway

    Grewia gum is a naturally occurring polysaccharide which has potential as a pharmaceutical excipient. Differential scanning\\u000a calorimetry and Fourier transform infrared (FT-IR) spectroscopy techniques were used to examine the thermal and molecular\\u000a behaviours, respectively, of mixtures of grewia gum with cimetidine, ibuprofen or standard excipients, to assess potential\\u000a interactions. No disappearance or broadening of the melting endotherm was seen with

  2. Gum mastic increases maspin expression in prostate cancer cells

    Microsoft Academic Search

    Mei-lan He; Wei-wen Chen; Peng-ju Zhang; An-li Jiang; Wei Fan; Hui-qing Yuan; Wen-wen Liu; Jian-ye Zhang

    2007-01-01

    Aim:To study whether gum mastic, a natural resin, can regulate maspin expression in prostate cancer cells, and further investigate the mechanisms involved in this regulatory system.Methods:RT-PCR and Western blotting were used to detect maspin expression at the transcriptional and translational levels. Reporter gene assay was used to investigate the effect of gum mastic on the maspin promoter. The binding activity

  3. Xanthan gum biosynthesis and application: a biochemical?\\/genetic perspective

    Microsoft Academic Search

    A. Becker; F. Katzen; A. Pühler; L. Ielpi

    1998-01-01

    Xanthan gum is a complex exopolysaccharide produced by the plant-pathogenic bacterium Xanthomonas campestris pv. campestris. It consists of D-glucosyl, D-mannosyl, and D-glucuronyl acid residues in a molar ratio of 2:2:1 and variable proportions of O-acetyl and pyruvyl residues. Because of its physical properties, it is widely used as a thickener or viscosifier in both\\u000a food and non-food industries. Xanthan gum

  4. Malva nut gum. (Part I): Extraction and physicochemical characterization

    Microsoft Academic Search

    P. Somboonpanyakul; Q. Wang; W. Cui; S. Barbut; P. Jantawat

    2006-01-01

    Malva nut is the seed of Scaphium scaphigerum and has long been used as a traditional medicine in South East Asia. This paper reports on the extraction and characterization of gums from malva nut seed. Sequential extraction with water, 0.05M HCl, and 0.05M NaOH solutions resulted in 1, 6 and 20% gum yield, respectively, based on the dry weight of

  5. Chemical composition of oleo-gum-resin from Ferula gummosa

    Microsoft Academic Search

    Hossein T. Jalali; Zahra J. Ebrahimian; Dmitry V. Evtuguin; Carlos Pascoal Neto

    2011-01-01

    The chemical composition of oleo-gum-resin from Ferula gummosa collected in the northern part of Iran has been studied. The fraction of oleo-gum-resin soluble in ethanol (ca 67wt.%) is composed by three major fractions: (i) monoterpenes and monoterpenoids (ca 15wt.% fraction), (ii) sesquiterpenes and sesquiterpenoids (ca 30wt.%) and (iii) triterpenes and triterpenoids (ca 55wt.%). The major families of terpenes and terpenoids

  6. A NEW SPECIES OF INVASIVE GALL WASP (HYMENOPTERA: EULOPHIDAE: TETRASTICHINAE) ON BLUE GUM (EUCALYPTUS GLOBULUS) IN CALIFORNIA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The blue gum gall wasp, Selitrichodes globulus La Salle & Gates (Hymenoptera: Eulophidae: Tetrastichinae), is described as an invasive gall inducer on blue gum, Eucalyptus globulus (Myrtaceae), in California....

  7. Evaluation of accelerated stability test conditions for medicated chewing gums.

    PubMed

    Maggi, Lauretta; Conte, Ubaldo; Nhamias, Alain; Grenier, Pascal; Vergnault, Guy

    2013-10-01

    The overall stability of medicated chewing gums is investigated under different storage conditions. Active substances with different chemical stabilities in solid state are chosen as model drugs. The dosage form is a three layer tablet obtained by direct compression. The gum core contains the active ingredient while the external layers are formulated to prevent gum adhesion to the punches of the tableting machine. Two accelerated test conditions (40°C/75% RH and 30°C/65% RH) are performed for 6 months. Furthermore, a long-term stability test at room conditions is conducted to verify the predictability of the results obtained from the stress tests. Some drugs are stable in all the conditions tested, but other drugs, generally considered stable in solid dosage forms, have shown relevant stability problems particularly when stress test conditions are applied to this particular semi-solid dosage forms. For less stable drugs, the stress conditions of 40°C/75% RH are not always predictable of chewing gum stability at room temperature and may produce false negative; intermediate conditions, 30°C/65% RH, are more predictive for this purpose, the results of drug content found after 6 months at intermediate stress conditions and 12 months at room conditions are generally comparable. But the results obtained show that only long-term conditions stability tests gave consistent results. During aging, the semi solid nature of the gum base itself, may also influence the drug delivery rate during chewing and great attention should be given also to the dissolution stability. PMID:22794248

  8. Effect of concentration on shear and extensional rheology of guar gum solutions

    E-print Network

    Torres, M. D.; Hallmark, B.; Wilson, D. I.

    2014-03-06

    ). Characterization of galactomannans extracted from seeds of Gleditsia triacanthos 541 and Sophora japonica through shear and extensional rheology: Comparison with guar gum 542 and locust bean gum. Food Hydrocolloids, 24, 184-192. 543 Brenner, M. P., Lister, J. R...

  9. Swallowing profiles of food polysaccharide gels in relation to bolus rheology

    Microsoft Academic Search

    Sayaka Ishihara; Makoto Nakauma; Takahiro Funami; Sachiko Odake; Katsuyoshi Nishinari

    2011-01-01

    Swallowing profiles of food polysaccharide gels were investigated in relation to bolus rheology. Polysaccharide gel from either gellan gum or a mixture of gellan gum and psyllium seed gum was used as a model food. Acoustic analysis and sensory evaluation were carried out to investigate the swallowing profiles using the same human subjects. Model bolus was prepared through instrumental mastication

  10. The effects of gums on macro and micro-structure of breads baked in different ovens

    Microsoft Academic Search

    Semin Ozge Ozkoc; Gulum Sumnu; Serpil Sahin

    2009-01-01

    In this study, the effects of gums on macro and micro-structure of breads baked in different ovens (infrared (IR)-microwave combination and conventional) were investigated by the help of image and SEM analysis, respectively. The gums used were xanthan, guar, ?-carrageenan and xanthan-guar blend. The gums were added to the formulation at 0.5% concentration. As a control, no gum added formulations

  11. Iodine derivatives of chemically modified gum Arabic microspheres.

    PubMed

    Ganie, Showkat A; Ali, Akbar; Mazumdar, Nasreen

    2015-09-20

    Acetylated gum Arabic (AGA) derivatives with different degrees of substitution (DS 0.97-2.74) were synthesized using acetyl chloride and a base under varying reaction conditions. The AGA derivatives were obtained in the form of microspheres and thereafter stable iodine products were prepared by doping the microspheres with an iodinating agent, iodine monochloride (ICl). The reaction between electrophilic iodine and polar carbonyl groups was studied by FT-IR, (1)H-NMR, and UV-VIS spectroscopies. The products were also characterized by DSC, TGA and SEM studies. The incorporated iodine was released in aqueous medium as iodide ions (I(-)). A reaction scheme has been proposed for the iodination and de-iodination of the gum derivatives. This work suggests that the iodine derivatives of modified gum Arabic could be used as a source of iodide ions which is the nutritional form of iodine. PMID:26050909

  12. Characteristics of the lactan gum produced from various carbon sources by Rahnella aquatilis

    Microsoft Academic Search

    K. Na; K.-Y. Lee

    1997-01-01

    The characteristics of the lactan gum produced by Rahnella aquatilis varied according to the carbon sources used: the steady shear viscosity of lactan gum produced from fructose medium was higher than that produced from the other carbon sources, and furthermore the level of energy required (D H), for the degradation of lactan gum from fructose by Rahnella aquatilis was higher

  13. Metabolic Effects of Nicotine Gum and Cigarette Smoking: Potential Implications for Postcessation Weight Gain?

    ERIC Educational Resources Information Center

    Klesges, Robert C.; And Others

    1991-01-01

    Twenty smoking women participated in nicotine gum and smoking administration, after which resting energy expenditures (REEs) were measured. Results indicated acute increase in REE for both nicotine gum and cigarettes. Metabolic rates for nicotine gum slowly returned to baseline; rates for cigarettes quickly fell significantly below baseline.…

  14. Influence of dehulling pretreatment on physicochemical properties of Gleditsia sinensis Lam. gum

    Microsoft Academic Search

    Hong-lei Jian; Carrasco Cristhian; Wei-ming Zhang; Jian-xin Jiang

    2011-01-01

    The seeds of Gleditsia sinensis Lam., widespread in China, are an important source of galactomannans. G. sinensis gum was extracted from whole seeds using baking, boiling water and acid dehulling pretreatment, respectively. The physicochemical properties of the three isolated G. sinensis gums were studied to evaluate three pretreatment methods. The results illustrated that the properties of G. sinensis gum were significantly

  15. Use of dye as tracer of drug release from medicated chewing gums

    Microsoft Academic Search

    Evelyn Ochoa; Lauretta Maggi; Stefania Conti; Ubaldo Conte; Guy Vergnault; Pascal Grenier

    2008-01-01

    The evaluation of the potential use of a dye as indicator of in vivo drug release from a medicated chewing gum is described. The device is a three-layer tablet obtained by direct compression consisting of a gum core and two external protective soluble layers to prevent gum adhesion to the punches of the tableting machine. The active ingredient and a

  16. Promoter analysis of the Xanthomonas campestris pv. campestris gum operon directing biosynthesis of the xanthan polysaccharide.

    PubMed Central

    Katzen, F; Becker, A; Zorreguieta, A; Pühler, A; Ielpi, L

    1996-01-01

    The Xanthomonas campestris gum gene cluster is composed of 12 genes designated gumB, -C, -D, -E, -F, -G, -H, -I, -J, -K, -L, and -M. The transcriptional organization of this gene cluster was analyzed by the construction of gum-lacZ transcriptional fusions in association with plasmid integration mutagenesis. This analysis, coupled with primer extension assays, indicated that the gum region was mainly expressed as an operon from a promoter located upstream of the first gene, gumB. PMID:8763965

  17. Effects of chewing gum on the stress and work of university students.

    PubMed

    Smith, Andrew P; Woods, Martin

    2012-06-01

    Recent research has indicated that chewing gum can relieve perceptions of stress in an occupational sample (Smith, 2009). In the present study, 72 students completed 2 weeks of either chewing gum or refraining from chewing gum. They completed scales measuring perceived stress, anxiety, depression, and single item measures of work levels and tiredness. These were completed both pre- and post-treatment. Perceived stress decreased as a function of the amount of gum chewed. The chewing gum condition was also associated with a decrease in not getting enough academic work done. There were no significant effects of chewing gum on mental health outcomes. These results confirm some of findings from previous studies of chewing gum and stress in other samples. PMID:22402304

  18. Effects of high hydrostatic pressure and chemical reduction on the emulsification properties of gum arabic.

    PubMed

    Ma, Fanyi; Bell, Alan E; Davis, Fred J; Chai, Yunxi

    2015-04-15

    Gum arabic is widely used in the food industry as an additive, both as a thickener and an emulsifier. This study has compared the emulsification properties of two types of gums, KLTA (Acacia senegal) and GCA (Acacia seyal), both in their native/untreated forms and after exposure to high pressure (800 MPa). Further studies were undertaken to chemically modify the disulphide linkages present and to investigate the effects of their reduction on the diffusion of the carbohydrate materials. The emulsification properties of the gum samples were examined by determining the droplet size distribution in a "model" oil-in-water system. Results showed that high pressure treatment and chemical reduction of gums changed the emulsification properties of both gums. The high molecular weight component in arabinogalactan-proteins (AGP/GP), and more "branched" carbohydrates present in gum arabic, may be responsible for the emulsification properties of GCA gum, indicating that the emulsification mechanisms for KLTA and GCA were different. PMID:25466061

  19. Guar gum: a miracle therapy for hypercholesterolemia, hyperglycemia and obesity.

    PubMed

    Butt, Masood Sadiq; Shahzadi, Naureen; Sharif, Mian Kamran; Nasir, Muhammad

    2007-01-01

    The number of hypercholesterolemic and hyperglycemic people is increasing rapidly in the world. The prevention against these health problems is related to a complex management of conventional and non-conventional risk factors. The inclusion of dietary fiber in the diet is the right approach to reduce these risks. Cholesterol and glucose lowering effects are most often associated with gelling, mucilaginous, and viscous fibers such as guar gum, an edible thickening agent. It has widespread applications in the food industry due to its ability to hydrate without heating. The demand for guar gum is still growing rapidly because in addition to its indispensable role in lowering serum cholesterol and glucose levels, it is also considered helpful in weight loss programs. The main thrust of therapeutic and medicinal properties lies in the soluble dietary fiber content of guar gum to improve the serum biochemical profile of human and non-human primates, reducing total serum cholesterol, triglycerides, increasing the high density lipoprotein cholesterol level, and the management of glycemic indices and obesity. Among the various intervention strategies, diet diversification is the right approach to overcome these problems. Composite flours containing wheat and legumes have proven practical uses and are being utilized in many parts of the world to improve the nutritional and functional properties of flour. The main focus of this manuscript is to review the available information on various aspects of guar gum with special reference to its effectiveness in reducing the cardiovascular disease risk, diabetes and weight loss programs. PMID:17457723

  20. Keep Gum Disease Away! | NIH MedlinePlus the Magazine

    MedlinePLUS

    ... of cavities, but I just didn't take care of them," he says. "In my 30s, I lost an upper back molar to gum disease. That was a signpost but I ignored it. It was false economy not to get my teeth checked." Slowly, but ...

  1. Seed surface gums content using the Dubois carbohydrate analysis

    Microsoft Academic Search

    Thomas P. Abbott; Terry C. Nelsen; Robert Kleiman

    1995-01-01

    The Dubois total carbohydrate method was applied to quantitative analysis of seed surface gums removed from Lesquerella seed by ultrasound. Between 20 and 30 seed samples could be tested in triplicate in a normal 8-h day. The analyses were repeatable with a coefficient of variation of 4%. Germination rates of seeds were unaffected by the sonic treatment. Of 16 Lesquerella

  2. Irrigation and planting density affect river red gum growth

    Microsoft Academic Search

    Stephen T. Cockerham

    2004-01-01

    In a 6-year study, production of river red gum, an excellent fuel-wood source, was evaluated for responses to three levels of irrigation, fertiliza- tion and planting density. Irrigation and planting density had the greatest influence on tree growth. Irrigation in the fifth and sixth years produced greater wood volume and weight per tree. Tree size was greatest in the wide

  3. Phenology of epigeous macrofungi found in red gum woodlands

    Microsoft Academic Search

    Mark Newbound; Michael McCarthy; Teresa Lebel

    2010-01-01

    The timing of fruiting body production by epigeous macrofungi is thought to be mostly determined by substrate moisture and temperature. Understanding the environmental cues that influence fruiting can help when designing surveys, interpreting results, and predicting effects of an altered climate. Species fruiting in 22 river red gum (Eucalyptus camaldulensis) woodland sites in southeastern Australia was recorded at regular intervals

  4. Effects of microfluidization on the functional properties of xanthan gum

    Microsoft Academic Search

    N Lagoueyte; P Paquin

    1998-01-01

    The effects of microfluidization on xanthan gum were studied by flow behaviour, hydration rate, water uptake and molecular weight determinations. The effect of pressure and number of passes on the xanthan solution produced a decrease in all these functional properties. Consequently the thickening and, stabilizing properties were reduced. We argued that the high shear, turbulence forces and cavitation involved in

  5. Oxygen transfer and uptake rates during xanthan gum production

    Microsoft Academic Search

    F Garc??a-Ochoa; E. Gómez Castro; V. E Santos

    2000-01-01

    Oxygen uptake rate and oxygen mass transfer rate have been studied during xanthan gum production process in stirred tank bioreactor. Empirical equations for the oxygen mass transfer coefficient have been obtained taking into account several variables such as air flow rate, stirrer speed and apparent viscosity. Oxygen uptake rate evolution in the course fermentation has been measured, obtaining an equation

  6. Nicotine Gum and Behavioral Treatment in Smoking Cessation.

    ERIC Educational Resources Information Center

    Hall, Sharon M.; And Others

    1985-01-01

    Assigned 120 smoking cessation subjects to either intensive behavioral treatment, nicotine gum in low-contact treatment, or to combined treatment. Combined treatment produced higher abstinence rates than other conditions at all assessments. Differences were significant at 3, 12, and 26 weeks, but not at 52 weeks. (NRB)

  7. Investigation of Transport Properties of a New Biomaterials - GUM Mangosteen

    NASA Astrophysics Data System (ADS)

    Pradhan, Sourav S.; Sarkar, A.

    2006-06-01

    Biomaterial has occupied leading position in material science for various scientific and technological applications. This present work is carried out over a natural gum extracted from raw fruit of Mangosteen, an east Indian tree (Gercinia Mangostana) following extraction and purification process. Solid specimen of the said gum is developed following sol-gel like process. AC and DC electrical analysis on the dried solid specimen of the gum were carried out and showed high electrical conduction with ? ~ 1 E-03 S/cm, of which ionic and electronic contributions are 70% and 30% respectively. Analysis shows that origin of high electrical conductivity is due to presence of substantial amount of organic acid unit in its polysaccharide background. In fact the observed ? is about 1000 times of that observed in gum Arabica. Optical absorption of this new bio- materials are also studied using UV-VIS analysis. The results show its high absorption co-efficient in UV and blue part of analysed range. A complete electrical characterization of the material have been made. It has also been observed that the electronic conduction can be enhanced to 70% of the total electrical conductivity by forming complex with Iodine and organic (Citric) acid from Lemon fruit. This high potential material is being studied for development of electronic device application.

  8. Tragacanth Gum: An Effective Oil Well Drilling Fluid Additive

    Microsoft Academic Search

    VIKAS MAHTO; V. P. SHARMA

    2005-01-01

    The low penetration rate, excessive torque and drag, poor hole cleaning and formation damage are major impediments in drilling oil and gas wells. These have a major impact on drilling efficiency and well economics. Keeping these in mind, an attempt was made to design a water based drilling fluid system using Indian bentonite clays and tragacanth gum. The effect of

  9. Improved emulsification performance of corn fiber gum following maturation treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn fiber gum (CFG) in the solid state (milled powder form) was subjected to a maturation treatment by heating under atmospheric pressure at 110 degrees C for 5 (CFG5) and 24 hours (CFG24). The treatment reduced the solubility and aggregation of the proteinaceous component with increased heating t...

  10. Guaranteed uncertainty management (GUM) for sensor provisioning in missile defense

    E-print Network

    Hero, Alfred O.

    of sensors, pulse repetitions, revisit rates) as a function of signal processing parameters (target SNRGuaranteed uncertainty management (GUM) for sensor provisioning in missile defense Alfred O Hero University of Michigan Ann Arbor, MI 48109-2122 March 10, 2008 Abstract Sensor provisioning is the problem

  11. Viscofying properties of corn fiber gum with various polysaccharides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of corn fiber gum (CFG) on the aqueous solutions of a series of widely-used commercial polysaccharides has been studied by rheological techniques using stress synergism index to evaluate its viscosifying action. Though CFG solution exhibited Newtonian fluid behaviour with a very low vis...

  12. Chewing gum increases energy expenditure before and after controlled breakfasts.

    PubMed

    Kresge, Daniel L; Melanson, Kathleen

    2015-04-01

    Chewing has been associated with improved satiation and satiety, but little is known about the metabolic impact of gum chewing. We tested the hypothesis that gum chewing would increase energy expenditure (EE) and reduce respiratory exchange ratio (RER) before and after a controlled test meal. Seventeen males and 13 females (age 21.5 ± 6.6 years, body mass index 23.9 ± 2.8 kg/m(2)) participated in a randomized crossover study in which subjects chewed sugar-free gum for a total of 1 h (3 sessions of 20 min) on the test day (GC) and did not chew gum on a control day (NG). EE and RER were measured by indirect calorimetry after an overnight fast. Subjects consumed a breakfast shake containing 30% of their measured energy needs, and then postprandial EE and RER were measured for 3 h. Blood glucose (GLC) was measured in the fasting and postprandial states at regular intervals. Fasting EE was higher during GC (1.23 ± 0.04 kcal/min; 1 kcal = 4.2 kJ) than during NG (1.17 ± 0.04 kcal/min; p = 0.016). Postprandial EE was also higher during GC (1.46 ± 0.05 kcal/min) than during NG (1.42 ± 0.05 kcal/min; p = 0.037). Fasting and postprandial RER and GLC did not differ between GC and NG. The findings demonstrate that GC is associated with higher fasting and postprandial EE without altering blood glucose or substrate oxidation as measured by RER. These data suggest that gum chewing potentially could influence short-term energy balance in this population; however, longer-term research is needed. PMID:25794237

  13. Contribution of lipids, phenolic acids, and protein rich components to emulsifying properties of corn fiber gum and acacia gum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn fiber gum (CFG) is an arabinoxylan enriched fraction obtained by the extraction of corn bran/fiber using a proprietary alkaline hydrogen peroxide process. When purified CFG prepared by this process was hydrolyzed with concentrated base (1.5 N methanolic KOH at 70 °C for one hour) considerable ...

  14. THE ROLE OF PROTEIN AND LIPID COMPONENTS IN THE EMULSIFICATION PROPERTIES OF CORN FIBER GUM AND GUM ARABIC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn Fiber Gum (CFG) is an arabinoxylan (hemicellulose) extracted from the kernel pericarp and/or endosperm fiber fractions of corn fiber which is the main low value by-product of the corn wet and/or dry milling processes. CFG-1 and 2 were isolated from corn fiber collected from different wet or dr...

  15. In vitro tooth whitening effect of two medicated chewing gums compared to a whitening gum and saliva

    Microsoft Academic Search

    Michael Moore; Nathalie Hasler-Nguyen; Geoffrey Saroea

    2008-01-01

    BACKGROUND: Extrinsic staining of teeth may result from the deposition of a variety of pigments into or onto the tooth surface, which originate mainly from diet or from tobacco use. More recently, clinical studies have demonstrated the efficacy of some chewing gums in removing extrinsic tooth staining. The aim of this study was to assess the effectiveness of two nicotine

  16. Socio-economic aspects of Gum Arabic production in Dalanj area, South Korodofan, Sudan.

    PubMed

    Koli, A O; Eltayeb, A M; Sanjak, E M; Mohammed, M H

    2013-11-01

    Acacia senegal (locally: Hashab tree) is one of the most important tree species in Sudan as it considers the main Gum Arabic producing tree. The objective of this study is to investigate the socio-economic aspects of gum Arabic production and to assess contribution of gum Arabic to sustainable livelihood of local people in Dalanj Locality, South Kordofan State-Sudan. Social survey was carried out by using structured questionnaire for 80 respondents (gum producers) on random sample basis in eight villages, 10 respondents from each village. Issues pertaining to socio-economic factors affecting gum Arabic production and contribution of gum Arabic to sustainable livelihood of local people, in Dalanj Locality, were assessed. Results of the study revealed that expansion of agriculture lands at the expense of hashab trees, fires and illegal felling are the most important factors constraining gum production in the area. The results also indicated that agriculture is the main source of income and gum Arabic is a supplementary source of income. The importance of gum Arabic becomes apparent during (off farm season) the period between crops harvest and the preparation of the next agricultural season. Establishment of producers' associations and provision of loans to producers are highly recommended to ensure sustainability of gum production. PMID:24511757

  17. Absence of coreshine in the Gum/Vela region

    NASA Astrophysics Data System (ADS)

    Pagani, L.; Lefèvre, C.; Bacmann, A.; Steinacker, J.

    2012-05-01

    Context. We recently discovered mid-infrared light scattering by micron-size grains deeply buried in dark clouds. We have named this coreshine. We also showed that this effect is widespread across the Galaxy except in the Gum/Vela region, the only region among those we explored without any trace of coreshine. Aims: We aim to check whether the Gum/Vela situation is a chance effect or if coreshine is really absent from the region. Methods: We explored the entire available Spitzer/InfraRed Red Array Camera (IRAC) archive centered on the Gum/Vela region in search of the coreshine effect. Results: Out of 24 validated objects (of a total of 32), we found three cases of coreshine and three possible other cases, while we detect nine cases of non-coreshine emission (bright rimmed clouds - BRC - or polycyclic aromatic hydrocarbon - PAH - emission). This is markedly different from our previous galactic-wide survey with a ratio of 7-8 coreshine cases per PAH case. In Gum/Vela, a majority of the clouds with protostars or young stellar objects do not show a coreshine effect, while in the galactic-wide survey, 75% of the protostellar clouds do. Conclusions: The rare occurence of coreshine, outnumbered by PAH and BRC cases, together with a large number of protostars, let us conclude that the Gum Nebula is a supernova remnant (SNR), and that the blast wave has both reset the grain size distribution and induced the formation of several protostars. The absence of coreshine in the vicinity of several of the Class I objects also implies that the growth time for grains to efficiently scatter mid-infrared radiation exceeds the Class I life duration, which is typically 2 × 105 years, and it also implies that the blast wave has reached these clouds only recently despite the age of the Gum region (over 1.5 My). This is consistent with their large distance from the center of the SNR. Appendices B and C are available in electronic form at http://www.aanda.org

  18. Locust bean gum: Exploring its potential for biopharmaceutical applications

    PubMed Central

    Dionísio, Marita; Grenha, Ana

    2012-01-01

    Polysaccharides have been finding, in the last decades, very interesting and useful applications in the biomedical and, specifically, in the biopharmaceutical field. Locust bean gum is a polysaccharide belonging to the group of galactomannans, being extracted from the seeds of the carob tree (Ceratonia siliqua). This polymer displays a number of appealing characteristics for biopharmaceutical applications, among which its high gelling capacity should be highlighted. In this review, we describe critical aspects of locust bean gum, contributing for its role in biopharmaceutical applications. Physicochemical properties, as well as strong and effective synergies with other biomaterials are described. The potential for in vivo biodegradation is explored and the specific biopharmaceutical applications are discussed. PMID:22923958

  19. In situ remineralization of subsurface enamel lesion after the use of a fluoride chewing gum.

    PubMed

    Lamb, W J; Corpron, R E; More, F G; Beltran, E D; Strachan, D S; Kowalski, C J

    1993-01-01

    In situ remineralization of early enamel lesions by a fluoride chewing gum was studied. Human enamel specimens with subsurface lesions were mounted in removable lower appliances for 6 adults. Subjects used a F-free dentifrice 3x/day and chewed five sticks/day for the F gum group (0.1 mg F/stick) or five sticks of sugarless gum. No gum was chewed for controls. Surface microhardness was performed on: (1) sound enamel; (2) lesions; (3) after intraoral exposure, and (4) after acid-resistance testing (ART). Separate specimens were etched and measured for F uptake and image analyses on microradiographs were performed for all regimens. delta Z values were calculated and converted to percent of mineralization. Values for F gum were significantly higher (p > 0.05) than non-F gum and controls for ART, percent remineralization, and F uptake up to 70 microns depth. PMID:8319253

  20. Evaluation of the flow properties of xanthan gum solution

    SciTech Connect

    Duda, J.L.; Klaus, E.E.; Leung, W.C.

    1981-02-01

    In this study, the solution properties of two forms of xanthan gum, a powder and a broth, which are commercially available were evaluated. As previous studies have shown, the solutions prepared from the broth do exhibit better injectivity properties. However, this investigation also shows that other properties of these solutions are not equivalent. In its natural state, xanthane gum exists as a multistranded helix. This ordered confirmation can be destroyed and in a denatured state, the xanthan gum exhibits a more random configuration and consequently higher viscosity. One of the major conclusions of this study is that the xanthan powder is partially denatured when compared to the xanthan molecules which exist in the broth. This denaturing may occur during the drying process in which the xanthan solids are removed from the broth. Solutions prepared from the broth in the absence of the added salt show a transition in the viscosity-temperature relationship at approximately 40 to 50/sup 0/C. This is consistent with the behavior of native xanthan gum solutions. At approximately 50/sup 0/C, the molecules in solution go into a more random state and consequently, an abrupt rise in the viscosity is observed. However, solutions prepared from the polymer powder do not show any evidence of such a transition. The solutions prepared from the broth can be thermally denatured, and this denaturing results in viscosities which are equivalent to the viscosities realized with the powdered polymer. Before denaturing, the broth solution showed a lower viscosity. Further, intrinsic viscosity measurements indicate that the hydrodynamic volume of the polymer solutions prepared from the borth are smaller than the hydrodynamic volumes of solutions prepared from the powder.

  1. Synergistic gelation of xanthan gum with locust bean gum: a rheological investigation.

    PubMed

    Copetti, G; Grassi, M; Lapasin, R; Pricl, S

    1997-12-01

    Many industrial products often include in their formulation more than one polysaccharide to achieve the desired properties during and after processing. Many such mixed systems behave as would be expected from the known properties of the individual polymers. In others, however, their properties are superior to those of either component alone, or may be qualitatively different. In many polysaccharide systems, the combination of a gelling polymer with a nongelling one gives rise to strong synergistic effects, as a consequence of interaction among different chain polymers and formation of mixed junction zones. Probably, the most exploited mixed gels, especially by the food industry, are those involving the microbial polysaccharide xanthan gum (XG) and the plant galactomannans, like locust bean gum (LBG). Concentrated aqueous systems of LBG and XG display quite different rheological properties: the former show the behaviour typical of hyperentangled macromolecular solutions, whereas the flow and viscoelastic properties of XG systems correspond to those of tenuous, weak-gel networks. Interestingly, when mixed together these macromolecules interact to form a firm, thermoreversible gel with synergistic effects. In the present paper we report the results of a thorough investigation of both polymer concentration and temperature effects on the rheological properties of mixed LBG-XG systems in 20 mM KCl under continuous and oscillatory flow conditions. Under continuous shear at 25 degrees C, pure LBG shows the flow properties of a macromolecular solution, with a shear-thinning behaviour and a Newtonian region at low shear rates, whereas the rheological behaviour of XG and all LX mixed systems is that typical of weak-gels. Furthermore, in the mixed systems the viscosity values do not increase monotonically with increasing xanthan concentration, but the synergistic effect has a maximum in accordance with the XG:LBG ratio 1:1. As the temperature is increased from 25 degrees C to 85 degrees C, whilst the LBG system do not show any qualitative change but there is only a parallel, downward shift of viscosity values, in the case of xanthan there is a dramatic change in the corresponding curve profiles, due to the thermally induced helix-coil conformational transition. The differences in the rheological behaviour of the systems examined can be better shown through dynamic tests at 25 degrees C. The strain sweeps performed at constant frequency of oscillation reveal that the mixed systems show higher sensitivity to strain amplitude, and lower strain values must be attained to ensure linear viscoelastic properties. The mechanical spectra clearly show the influence of composition on the viscoelastic properties of these biopolymer systems. All LX systems show the mechanical spectra typical of polysaccharide gels: G' is always much greater than G" and is nearly independent of the applied frequency over a wide frequency range. In addition, the marked gap between the elastic responses of the pure LBG and the LX 1:3 systems demonstrates the strong effect of the initial addition of xanthan to the pure LBG, especially in the low frequency range, whereas the highest synergistic effect is attained for the LX 1:1 system. A comprehensive description of the frequency dependence of both moduli can be suitably obtained through the four-parameter Friedrich model, which belongs to the class of fractional derivative approaches viscoelasticity. The same thermal effect is observed for the XG and all LX mixed systems considered, indicating a progressive change from the behaviour of a typical gel to that of a quasi-solution state, when temperature is increased from 25 degrees C to 85 degrees C. Among all mixed systems, the LX 1:1 has the highest values of the moduli at any temperature considered, and is characterized by the highest gel-sol transition temperature. (ABSTRACT TRUNCATED) PMID:9486428

  2. Low viscosity hydrogel of guar gum: preparation and physicochemical characterization.

    PubMed

    Cunha, Pablyana L R; Castro, Rondinelle R; Rocha, Francisco A C; de Paula, Regina C M; Feitosa, Judith P A

    2005-10-30

    Guar gum was cross-linked with glutaraldehyde and characterized by GPC, rheology, WADX, SEM and TGA. This guar gum is a galactomannan polysaccharide, that contains small amount of arabinose, glucose and uronic acid, besides galactose and mannose. The polymer has high molar mass, with Mw, Mn and Mv values of 2.0x10(6), 1.2x10(6) and 1.9x10(6)g/mol, respectively. The reticulation follows a slow process and lead to a viscosity increase of 40 times compared with the original gum solution. The final viscosity was similar to that of Hylan G-F 20, a hyaluronate derivative, commercially used in viscosupplementation treatment. The gel contains 95.6% of water and the amount of residual glutaraldehyde is much lower than the LD-50. Porous structure was detected by SEM and thermal stability was improved by the cross-linking. The low viscosity, the small amount of remained glutaraldehyde, and the thermal stability indicates that the guar hydrogel has potential to be applied as biomaterial with specific rheological requirements. PMID:16221491

  3. Insulin chewing gum: Need of the day for diabetic patients

    PubMed Central

    Mateti, Uday Venkat; Adla, Nagesh; Rajakannan, Thiyagu; Valakkathala, Rajesh

    2011-01-01

    Chewing gum is an excellent drug delivery system for self medication as it is convenient, can be administered discreetly without water and offers the removal of ‘needle fear’ for the patients. As it releases insulin orally, it helps in tackling of the deprivation of insulin by digestive enzyme without adding digestive enzyme inhibitor. This can be done by binding of vitamin B12 and insulin. The vitamin B12 is protected with haptocorrin which is a salivary protein. Another chemical pathway takes over to help vitamin B12 pass into the bloodstream as haptocorrin reaches the intestines. The binding of vitamin B12 and insulin molecules makes the insulin to be protected on this supply chain. The insulin could ride all the way into the bloodstream, where it is released to do its work. By stimulating the brain, chewing gum also increases the releases of insulin. Finding simpler ways to deliver insulin into the blood stream is one important avenue for tackling the diabetes epidemic that is sweeping the developed world. The conditions in gastrointestinal tract may damage the body's protecting and absorbing mechanisms for the valuable molecules. Chewing gum would be a better delivery method in humans. PMID:23071934

  4. The effect of mastic gum on Helicobacter pylori: A randomized pilot study

    Microsoft Academic Search

    K. J. Dabos; E. Sfika; L. J. Vlatta; G. Giannikopoulos

    2010-01-01

    Our aim was to study the effect of pure mastic gum on Helicobacter pylori (H. pylori) eradication in patients suffering from an H. pylori infectionFifty two patients were randomized to receive either 350mg three times a day (tid) of pure mastic gum for 14 days (Group A), or 1,05g tid of pure mastic gum (Group B) for 14 days, or

  5. Optimization of xanthan gum production by Xanthomonas campestris grown in molasses

    Microsoft Academic Search

    Stavros Kalogiannis; Gesthimani Iakovidou; Maria Liakopoulou-Kyriakides; Dimitrios A Kyriakidis; George N Skaracis

    2003-01-01

    Xanthan gum production by Xanthomonas campestris ATCC 1395 using sugar beet molasses as carbon source was studied. The pre-treatment of sugar beet molasses and the supplementation of the medium were investigated in order to improve xanthan gum production. Addition of K2HPO4 to the medium had a significant positive effect on both xanthan gum and biomass production. The medium was subsequently

  6. Effect of gel-forming gums on the intestinal unstirred layer and sugar transport in vitro

    Microsoft Academic Search

    I T Johnson; J M Gee

    1981-01-01

    The effect of two gel-forming polysaccharide gums, guar gum and Na-carboxymethyl-cellulose (CMC), on glucose transport in vitro was investigated using everted sacs of rat jejunum. The gums were added to the mucosal bathing media to give apparent viscosities in the range of 1-110 Pascal seconds X 10(-3), mPa.s(cP). Serosal glucose transport fell steeply by about 60% as the viscosities of

  7. Nutritional and Digestive Challenges to Being a Gum-Feeding Primate

    Microsoft Academic Search

    Michael L. Power

    \\u000a Gum is an unusual food that presents significant challenges to animals that feed on it. Gum is limited in availability; trees\\u000a generally secrete it only in response to damage. Gum is a ?-linked complex polysaccharide, and as such is resistant to mammalian\\u000a digestive enzymes and requires fermentation by gut microbes. It contains little or no lipid, low amounts of protein,

  8. Synthesis and devolatilization of M-97 NVB silicone gum compounded into silica reinforced silicone base

    SciTech Connect

    Schneider, J.W.

    1986-06-01

    Silica reinforced silicon bases having 0.31 weight percent vinyl content were prepared by using a blend of low and high vinyl content devolatilized M-97 NVB silicone gum. The M-97 NVB is a custom dimethyl-, diphenyl-, methylvinylsiloxane gum. The silicon gum was devolatilized to evaluate the anticipated improved handling characteristics. Previous procured batches of M-97 NVB had not been devolatilized and difficult handling problems were encountered. The synthesis, devolatilization, and compound processes for the M-97 NVB silicone gum are discussed.

  9. Locust bean gum: processing, properties and food applications--a review.

    PubMed

    Barak, Sheweta; Mudgil, Deepak

    2014-05-01

    Locust bean gum or carob gum is a galactomannan obtained from seed endosperm of carob tree i.e. Ceratonia siliqua. It is widely utilized as an additive in various industries such as food, pharmaceuticals, paper, textile, oil well drilling and cosmetics. Industrial applications of locust bean gum are due to its ability to form hydrogen bonding with water molecule. It is also beneficial in the control of many health problems like diabetes, bowel movements, heart disease and colon cancer due to its dietary fiber action. This article focuses on production, processing, composition, properties, food applications and health benefits of locust bean gum. PMID:24548746

  10. Viscoelastic and fragmentation characters of model bolus from polysaccharide gels after instrumental mastication

    Microsoft Academic Search

    Sayaka Ishihara; Makoto Nakauma; Takahiro Funami; Sachiko Odake; Katsuyoshi Nishinari

    2011-01-01

    Model bolus from polysaccharide gels was investigated by the stress-relaxation tests and particulate size analyses. Using two gelling agents, gellan gum and a composite of gellan\\/psyllium seed gums, gels with different physical properties (i.e., elastic gellan single gels and plastic composite gels) and gel hardness were prepared. Gels were masticated instrumentally in the presence or absence of artificial saliva to

  11. A new species of invasive gall wasp (Hymenoptera: Eulophidae: Tetrastichinae) on blue gum (Eucalyptus globulus) in California

    Microsoft Academic Search

    JOHN LA SALLE; GEVORK ARAKELIAN; ROSSER W. GARRISON; MICHAEL W. GATES

    The blue gum gall wasp, Selitrichodes globulus La Salle & Gates, n. sp. (Hymenoptera: Eulophidae: Tetrastichinae), is described as an invasive gall inducer on blue gum, Eucalyptus globulus Labill. (Myrtaceae), in California.

  12. Physical and chemical stability of gum arabic-stabilized conjugated linoleic acid oil-in-water emulsions.

    PubMed

    Yao, Xiaolin; Xu, Qiong; Tian, Dazhi; Wang, Nana; Fang, Yapeng; Deng, Zhongyang; Phillips, Glyn O; Lu, Jiang

    2013-05-15

    Oil-in-water (O/W) emulsions have been used as a delivery system to protect conjugated linoleic acid (CLA), a polyunsaturated fatty acid, from oxidation. Conventional gum arabic (GA) and two matured gum arabic samples (EM2 and EM10) were used as emulsifiers to prepare CLA-in-water emulsions. The emulsions have optimal physical and chemical stability at gum concentrations of 5% for all three gums. Emulsions with higher gum concentrations are more susceptible to lipid oxidation. This is attributed to reduced physical stability at higher gum concentrations because of the coalescence and depletion-induced flocculation of the emulsion droplets. The prooxidants iron and copper intrinsically contained in the gums could also contribute to this instability. Among the three gums, EM10 provides the most effective protection for CLA both physically and chemically, because of its superior interfacial properties over GA and EM2. PMID:23614832

  13. Polyelectrolyte complex materials consisting of antibacterial and cell-supporting layers.

    PubMed

    Mat Amin, Khairul Anuar; Gilmore, Kerry J; Matic, Jake; Poon, Stephen; Walker, Mark J; Wilson, Mark R; in het Panhuis, Marc

    2012-03-01

    The characterization of a polyelectrolyte complex material comprised of two biopolymers, a chitosan upper layer and a gellan gum under layer, is reported. It is shown that the upper layer of chitosan with incorporated levofloxacin displays an antibacterial activity, while the under layer of a gellan gum/TiO(2) composite supports the growth of fibroblastic cells. PMID:22223665

  14. Experimental and simulation studies of zone isolation in horizontal wells 

    E-print Network

    Tan, Joo Sitt

    1997-01-01

    for the study: TEXPLUG, K-@ and KELCO gellan gum. Experiments were conducted to "weaken" the TEXPLUG plugs, and to "strengthen" the K-MAX and KELCO gellan gum plugs by varying the concentrations of the polymer, cross-linker and, where applicable, the solvent...

  15. Gum chewing improves adolescents’ math performance in an SAT preparatory course

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of the current study was to determine the effect of gum chewing on students’ performance in a preparatory course for the Scholastic Aptitude Test (SAT). A total of 182 adolescents enrolled in an SAT preparatory class were randomized into one of two treatments: 1) gum chewing condition (G...

  16. Reduction of lipid oxidation by formation of caseinate-oil-oat gum emulsions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concentration of oat gum, though important for formation of stable emulsion, has no effect on oxidation of Omega 3 oil; this is most prominent in fish-oil based Omega 3 oil. The optimal concentration of oat gum is about 0.2% wt for emulsion stability and visual appearance. We found that concentr...

  17. CHEMICAL AND COMPOSITION OF AN EFFECTIVE EMULSIFIER SUBFRACTION OF GUM ARABIC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gum arabic, which is principally a mixture of polysaccharides and arabinogalactan-proteins (AGPs), contains trace levels of lipids. This report explores the hypothesis that these lipids are attached to the gum arabic AGPs as glycosyl-phosphatidylinositol (GPI) lipids, or in some other way, and make...

  18. Use of map analysis to elucidate flooding in an Australian Riparian River Red Gum Forest

    Microsoft Academic Search

    L. J. Bren; I. C. O'Neill; N. L. Gibbs

    1988-01-01

    Red gum (Eucalyptus camaldulensis) forests occur on extensive floodplains along the river Murray in Australia. This type of forest is unusual because of its high quality in a semiarid area, the absence of woody species other than red gum, and its survival on a deep, intractable, swelling clay soil of depths exceeding 20 m. This soil probably acts as an

  19. Xanthan gum production under several operational conditions: molecular structure and rheological properties

    Microsoft Academic Search

    J. A Casas; V. E Santos; F Garc??a-Ochoa

    2000-01-01

    Xanthan gum production under several operational conditions has been studied. Temperature, initial nitrogen concentration and oxygen mass transfer rate have been changed and average molecular weight, pyruvilation and acetylation degree of xanthan produced have been measured in order to know the influence of these variables on the synthesised xanthan molecular structure. Also, xanthan gum solution viscosity has been measured, and

  20. RHEOLOGICAL STUDY OF XANTHAN AND LOCUST BEAN GUM INTERACTION IN DILUTE SOLUTION: EFFECT OF SALT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An oscillatory capillary rheometer was used to investigate the effects of NaCl, KCl, and CaCl2 on visco-elastic properties of xanthan and locust bean gum (LBG) blends in dilute solution. Gums were evaluated for intrinsic viscosity and elastic component. Molecular conformation of the xanthan-LBG comp...

  1. Surface and emulsification properties of a new gum extracted from Portulaca oleracea L

    Microsoft Academic Search

    N. Garti; Y. Slavin; A. Aserin

    1999-01-01

    Hydrocolloids are water-soluble polysaccharides used mainly as food stabilizers. We are searching for a new surface active gums as an alternative to the gum Arabic. Efforts are being made to extract some new water-soluble polysaccharides from selected plants, preferably free of proteineous matter and exhibiting low viscosity and to examine their surface, interfacial and emulsification properties. The present study explores

  2. Adverse Reaction to Nicotine Gum in Malay Female Smoker: A Case Report

    ERIC Educational Resources Information Center

    Noorzurani, Md Haris Robson; Bond, Alyson; Wolff, Kim

    2008-01-01

    Nicotine replacement therapies (NRT) are prescribed in smoking cessation programmes to help smokers stop smoking. The ideal dosage of NRT should control cravings and withdrawal symptoms but avoid adverse reactions. This report describes a case of adverse reaction to nicotine gum in a female Malay smoker. Assays taken 2 h after the gum, showed that…

  3. Injectivity Improvement of Xanthan Gums by Enzymes: Process Design and Performance Evaluation

    Microsoft Academic Search

    N. Kohler; D. Lonchamp; M. Thery

    1987-01-01

    Injectability and filterability of xanthan gum dispersions, especially in hard brines, can be considerably improved by successive use of cellulase and alkaline protease enzyme treatments. A thorough optimization of the different parameters controlling enzymatic activity has led to an original clarification process. Improvements observed in flow behavior of treated xanthan gum solutions through reservoir rocks is the result of almost

  4. Production of Recombinant Plant Gum With Tobacco Cell Culture in Bioreactor

    E-print Network

    Kieliszewski, Marcia

    to cell wall networks and the plasma membrane cell wall interface (Lamport and Northcote, 1960; SerpeProduction of Recombinant Plant Gum With Tobacco Cell Culture in Bioreactor and Gum-rich glycoproteins (HRGPs), which are also abundant components of the plant cell extracellular matrix. Here we

  5. Mutans Streptococci Dose Response to Xylitol Chewing Gum

    Microsoft Academic Search

    P. Milgrom; K. A. Ly; M. C. Roberts; M. Rothen; G. Mueller; D. K. Yamaguchi

    2006-01-01

    Xylitol is promoted in caries-preventive strategies, yet its effective dose range is unclear. This study determined the dose-response of mutans streptococci in plaque and unstimulated saliva to xylitol gum. Participants (n = 132) were randomized: controls (G1) (sorbitol\\/maltitol), or combinations giving xylitol 3.44 g\\/day (G2), 6.88 g\\/day (G3), or 10.32 g\\/day (G4). Groups chewed 3 pellets\\/4 times\\/d. Samples were taken

  6. Composition and physicochemical properties of Zedo gum exudates from Amygdalus scoparia.

    PubMed

    Fadavi, Ghasem; Mohammadifar, Mohammad Amin; Zargarran, Azizollaah; Mortazavian, Amir Mohammad; Komeili, Rozita

    2014-01-30

    Composition and physicochemical properties of three types of Zedo gum exudates from Amygdalus scoparia were investigated. Monosaccharide analysis by GC-MS indicated the occurrence of arabinose and galactose as the main sugars. FTIR spectra showed no differences in functional groups among the samples. Steady shear rheological data and power law parameters revealed that the white gum (W) was the most shear sensitive type and had the highest value of consistency coefficient. The mechanical spectra derived from the strain and frequency sweep measurements indicated a liquid viscoelastic behavior for Zedo gum dispersions. GPC-MALLS revealed that the white sample had the highest apparent average molecular weight (4.74 × 10(6)Da) and the lowest dispersity (1.045). TG-DTA analysis showed that the character of gum decomposition significantly depended on the gum type and the white sample had the highest thermal stability. PMID:24299876

  7. Influence of gamma radiation on the physicochemical and rheological properties of sterculia gum polysaccharides

    NASA Astrophysics Data System (ADS)

    Singh, Baljit; Sharma, Vikrant

    2013-11-01

    Keeping in view the influence of gamma radiation on the physiochemical properties of the polysaccharides and their importance in the food and pharmaceutical industry, in the present study attempt has been made to investigate the effects of absorbed dose on FTIR, XRD, SEMs, absorbance, pH, solubility, water absorption capacity, emulsion stability and rheology of sterculia gum. Increase in solubility and decrease in swellability of gum has been observed on increasing the absorbed dose. The emulsion stability has improved for the gum sample irradiated with total dose of 8.1±0.2 kGy. Apparent viscosity of gum solution first increased with increase in dose from 0 to 8.1±0.2 kGy than decreased with regular trends with further increase in total absorbed dose. Flow behavior of gum solution shifted to Newtonian from non-Newtonian with increasing the dose.

  8. Modified gum arabic cross-linked gelatin scaffold for biomedical applications.

    PubMed

    Sarika, P R; Cinthya, Kuriakose; Jayakrishnan, A; Anilkumar, P R; James, Nirmala Rachel

    2014-10-01

    The present work deals with development of modified gum arabic cross-linked gelatin scaffold for cell culture. A new biocompatible scaffold was developed by cross-linking gelatin (Gel) with gum arabic, a polysaccharide. Gum arabic was subjected to periodate oxidation to obtain gum arabic aldehyde (GAA). GAA was reacted with gelatin under appropriate pH to prepare the cross-linked hydrogel. Cross-linking occurred due to Schiff's base reaction between aldehyde groups of oxidized gum arabic and amino groups of gelatin. The scaffold prepared from the hydrogel was characterized by swelling properties, degree of cross-linking, in vitro degradation and scanning electron microscopy (SEM). Cytocompatibility evaluation using L-929 and HepG2 cells confirmed non-cytotoxic and non-adherent nature of the scaffold. These properties are essential for generating multicellular spheroids and hence the scaffold is proposed to be a suitable candidate for spheroid cell culture. PMID:25175214

  9. Use of dye as tracer of drug release from medicated chewing gums.

    PubMed

    Ochoa, Evelyn; Maggi, Lauretta; Conti, Stefania; Conte, Ubaldo; Vergnault, Guy; Grenier, Pascal

    2008-03-01

    The evaluation of the potential use of a dye as indicator of in vivo drug release from a medicated chewing gum is described. The device is a three-layer tablet obtained by direct compression consisting of a gum core and two external protective soluble layers to prevent gum adhesion to the punches of the tableting machine. The active ingredient and a colour are contained in the gum core. To evaluate the drug and the dye release from the formulations, a chew-out study was performed by a panel of volunteers. The results obtained suggest that the use of a dye could be useful to indicate the chewing time necessary to complete drug delivery from medicated chewing gums. PMID:17951037

  10. Guar gum solutions for improved delivery of iron particles in porous media (part 1): porous medium rheology and guar gum-induced clogging.

    PubMed

    Gastone, Francesca; Tosco, Tiziana; Sethi, Rajandrea

    2014-10-01

    The present work is the first part of a comprehensive study on the use of guar gum to improve delivery of microscale zero-valent iron particles in contaminated aquifers. Guar gum solutions exhibit peculiar shear thinning properties, with high viscosity in static conditions and lower viscosity in dynamic conditions: this is beneficial both for the storage of MZVI dispersions, and also for the injection in porous media. In the present paper, the processes associated with guar gum injection in porous media are studied performing single-step and multi-step filtration tests in sand-packed columns. The experimental results of single-step tests performed by injecting guar gum solutions prepared at several concentrations and applying different dissolution procedures evidenced that the presence of residual undissolved polymeric particles in the guar gum solution may have a relevant negative impact on the permeability of the porous medium, resulting in evident clogging. The most effective preparation procedure which minimizes the presence of residual particles is dissolution in warm water (60°C) followed by centrifugation (procedure T60C). The multi-step tests (i.e. injection of guar gum at constant concentration with a step increase of flow velocity), performed at three polymer concentrations (1.5, 3 and 4g/l) provided information on the rheological properties of guar gum solutions when flowing through a porous medium at variable discharge rates, which mimic the injection in radial geometry. An experimental protocol was defined for the rheological characterization of the fluids in porous media, and empirical relationships were derived for the quantification of rheological properties and clogging with variable injection rate. These relationships will be implemented in the second companion paper (Part II) in a radial transport model for the simulation of large-scale injection of MZVI-guar gum slurries. PMID:25065767

  11. Evaluation of guar gum derivatives as gelling agents for microbial culture media.

    PubMed

    Gangotri, Waikhom; Jain-Raina, Ruchi; Babbar, Shashi B

    2012-05-01

    Guar gum, a galactomannan, has been reported to be an inexpensive substitute of agar for microbial culture media. However, its use is restricted probably because of (1) its highly viscous nature even at high temperatures, making dispensing of the media to Petri plates difficult and (2) lesser clarity of the guar gum gelled media than agar media due to impurities present in guar gum. To overcome these problems, three guar gum derivatives, carboxymethyl guar, carboxymethyl hydroxypropyl guar and hydroxypropyl guar, were tested as gelling agents for microbial growth and differentiation. These were also evaluated for their suitability for other routine microbiological methods, such as, enumeration, use of selective and differential media, and antibiotic sensitivity test. For evaluation purpose, growth and differentiation of eight fungi and eight bacteria grown on the media gelled with agar (1.5%), guar gum (4%) or one of the guar gum derivatives (4%), were compared. All fungi and bacteria exhibited normal growth and differentiation on all these media. Generally, growth of most of the fungi was better on guar gum derivatives gelled medium than on agar medium. The enumeration carried out for Serratia sp. and Pseudomonas aeruginosa by serial dilution and pour plate method yielded similar counts in all the treatments. Likewise, the selective succinate medium, specific for P. aeruginosa, did not allow growth of co-inoculated Bacillus sp. even if gelled with guar gum derivatives. The differential medium, Congo red mannitol agar could not differentiate between Agrobacterium tumefaciens and Rhizobium meliloti on color basis, if gelled with guar gum or any of its derivatives However, for antibiotic sensitivity tests for both Gram-positive and -negative bacteria, guar gum and its derivatives were as effective as agar. PMID:22806052

  12. Antinociceptive activity of Astragalus gummifer gum (gum tragacanth) through the adrenergic system: A in vivo study in mice

    PubMed Central

    Bagheri, Seyyed Majid; Keyhani, Leila; Heydari, Mehrangiz; Dashti-R, Mohammad Hossein

    2015-01-01

    Background: In Iranian traditional medicine, gum obtained from Astragalus gummifer and some other species of Astragalus was used as analgesic agent. Objective: In this study, we investigated the antinociceptive effect of several concentrations (125, 250, and 500 ?g/kg body weight) of Astragalus gummifer gum (AGG) on thermal and acetic acid induced pain in mice. Materials and Methods: AGG was dissolved in distillated water and injected i.p to male mice 15 minute before the onset of experiment. Writhing and hot-plate tests were applied to study the analgesic effect of AGG and compared with that of diclofenac sodium (30 mg/kg, i.p.) or morphine (8 mg/kg, i.p). To investigate the mechanisms involved in antinociception, yohimbine, naloxone, glibenclamide, and theophylline were used in writhing test. These drugs were injected intraperitoneally 15 min before the administration of AGG. The number of writhes were counted in 30 minutes and analyzed. Results: AGG exhibited a significant antinociceptive effect and the most effective dose of AGG was 500 ?g/kg. The most maximum possible effect (%MPE) was observed (117.4%) 15 min after drug administration. The %inhibition of acetic acid-induced writhing in AGG 125, 250 and 500 was 47%, 50% and 54% vs %15 of control and 66.3% of diclofenac sodium group. The antinociceptive effect induced by this gum in the writhing test was reversed by the systemic administration of yohimbine (?2-adrenergic antagonist), but naloxone, glibenclamide, and theophylline did not reverse this effect. Conclusions: The findings of this study indicated that AGG induced its antinociceptive through the adrenergic system. PMID:25878459

  13. Gum containing calcium fluoride reinforces enamel subsurface lesions in situ.

    PubMed

    Kitasako, Y; Sadr, A; Hamba, H; Ikeda, M; Tagami, J

    2012-04-01

    The aim of this study was to assess the effect of chewing gum containing phosphoryl oligosaccharides of calcium (POs-Ca) and a low concentration of fluoride (F) on the hardness of enamel subsurface lesions, utilizing a double-blind, randomized, and controlled in situ model. Fifteen individuals wore removable lingual appliances with 3 bovine-enamel insets containing subsurface demineralized lesions. Three times a day for 14 days, they chewed one of the 3 chewing gums (placebo, POs-Ca, POs-Ca+F). After the treatment period, cross-sectional mineral content, nanoindentation hardness, and fluoride ion mapping by time-of-flight secondary ion mass spectrometry (TOF-SIMS) were evaluated. Although there were no statistical differences in overall mineral content and hardness recovery rates between POs-Ca and POs-Ca+F subsurface lesions (p > 0.05), nanoindentation at 1-?m distance increments from the surface showed statistical differences in hardness recovery rate between POs-Ca and POs-Ca+F in the superficial 20-?m region (p < 0.05). Fluoride mapping revealed distribution of the ion up to 20 ?m from the surface in the POs-Ca+F group. Nanoindentation and TOF-SIMS results highlighted the benefits of bioavailability of fluoride ion on reinforcement of the superficial zone of subsurface lesions in situ (NCT01377493). PMID:22337700

  14. New structural features of Acacia tortuosa gum exudate.

    PubMed

    Martínez, Maritza; Beltrán, Olga; Rincón, Fernando; León de Pinto, Gladys; Igartuburu, José Manuel

    2015-09-01

    Acacia tortuosa produces a clear gum, very soluble in water. Previous reports showed that it was constituted by four fractions, one of them an arabinogalactan-protein complex. The elucidation of the A. tortuosa gum structure by the combination of classical chemical methods, size exclusion chromatography and NMR spectroscopy, was the objective of this investigation. The data obtained show that the heteropolysaccharide is an arabinogalactan type II, highly ramified, with lateral chains at C-2 as well as at C-6 of the galactose 3-O residues; mono-O-substituted galactoses were not detected. There are residues of mannose, the arabinose, pyranose predominantly, is terminal and 2-O-linked. The abundance of the 4-O-methyl-?-d-glucuronic acid was not previously reported. The proteic fraction is probably represented by an arabinogalactan-protein complex that binds poorly with ?-glucosyl Yariv reagent, and two glycoproteins. The NMR spectra suggest that the carbohydrate links to hydroxyproline through the galactose (galactosylation). PMID:25842315

  15. Guar gum based biodegradable, antibacterial and electrically conductive hydrogels.

    PubMed

    Kaith, Balbir S; Sharma, Reena; Kalia, Susheel

    2015-04-01

    Guar gum-polyacrylic acid-polyaniline based biodegradable electrically conductive interpenetrating network (IPN) structures were prepared through a two-step aqueous polymerization. Hexamine and ammonium persulfate (APS) were used as a cross linker-initiator system to crosslink the poly(AA) chains on Guar gum (Ggum) backbone. Optimum reaction conditions for maximum percentage swelling (7470.23%) were time (min) = 60; vacuum (mmHg) = 450; pH = 7.0; solvent (mL) = 27.5; [APS] (mol L(-1)) = 0.306 × 10(-1); [AA] (mol L(-1)) = 0.291 × 10(-3) and [hexamine] (mol L(-1))=0.356 × 10(-1). The semi-interpenetrating networks (semi-IPNs) were converted into IPNs through impregnation of polyaniline chains under acidic and neutral conditions. Fourier transform infra-red spectroscopy (FTIR), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) techniques were used to characterize the semi-IPNs and IPNs. Synthesized semi-IPNs and IPNs were further evaluated for moisture retention in different soils, antibacterial and biodegradation behavior. PMID:25660656

  16. Effects of prolonged gum chewing on pain and fatigue in human jaw muscles.

    PubMed

    Farella, M; Bakke, M; Michelotti, A; Martina, R

    2001-04-01

    Gum chewing has been accepted as an adjunct to oral hygiene, as salivary stimulant and vehicle for various agents, as well as for jaw muscle training. The aim of this study was to investigate the effects of prolonged gum chewing on pain, fatigue and pressure tenderness of the masticatory muscles. Fifteen women without temporomandibular disorders (TMD) were requested to perform one of the following chewing tasks in three separate sessions: chewing a very hard gum, chewing a soft gum, and empty-chewing with no bolus. Unilateral chewing of gum or empty chewing was performed for 40 min at a constant rate of 80 cycles/min. In each session, perceived muscle pain and masticatory fatigue were rated on visual analog scales (VAS) before, throughout, and after the chewing task. Pressure pain thresholds (PPTs) of masseter and anterior temporalis muscles were assessed before and immediately after the chewing tasks, and again after 24 h. The VAS scores for pain and fatigue significantly increased only during the hard gum chewing, and after 10 min of recovery VAS scores had decreased again, almost to their baseline values. No significant changes were found for PPTs either after hard or soft gum chewing. The findings indicate that the jaw muscles recover quickly from prolonged chewing activity in subjects without TMD. PMID:11347660

  17. Formulation development and evaluation of metformin chewing gum with bitter taste masking

    PubMed Central

    Mostafavi, Sayed Abolfazl; Varshosaz, Jaleh; Arabian, Saber

    2014-01-01

    Background: Medicated gums are intended to be chewed and act either locally, absorbed via the buccal mucosa or swallowed with saliva. We prepared the metformin gum to overcome its side effects including vomiting, diarrhea, and abdomen discomfort. Furthermore, it could be useful for those who have swallowing problems. Materials and Methods: Metformin hydrochloride (250 mg) with suitable sweeteners was mixed manually for 5 min. This mixture was spray dried, freeze dried, or directly mixed with chewing gum base. Glycerin, xylitol, and menthol were added and the produced paste was kept in the freezer for 2 h to be stable. As the metformin shows bitter taste, we tried to mask this unpleasant taste with using different methods explained. The releasing pattern was evaluated by using a mechanical chewing machine. The best formulation with the optimized releasing pattern, suitable physicochemical properties and pleasant taste were selected. Content uniformity, releasing percent, and other physicochemical properties were identified as well. Taste, flavor, and appearance characteristics were evaluated by using a self-made questionnaire based on the hedonic test method. Results: The chewing gum dosage content was about 86.2%. The release rate of metformin chewing gum was about 70% after 5 min of mastication. Masking the bitter taste of drug was achieved by using acesulfame-isomalt as sweeteners and prepared it by freeze drying equipment. Conclusion: Metfornin chewing gum had suitable appearance and appropriate invitro characteristics that fallow the pharmacopeia suggestions. This chewable gum showed bitterness suppression with a suitable release rate. PMID:24800181

  18. Chewing Gum: Cognitive Performance, Mood, Well-Being, and Associated Physiology

    PubMed Central

    Allen, Andrew P.; Smith, Andrew P.

    2015-01-01

    Recent evidence has indicated that chewing gum can enhance attention, as well as promoting well-being and work performance. Four studies (two experiments and two intervention studies) examined the robustness of and mechanisms for these effects. Study 1 investigated the acute effect of gum on mood in the absence of task performance. Study 2 examined the effect of rate and force of chewing on mood and attention performance. Study 3 assessed the effects of chewing gum during one working day on well-being and performance, as well as postwork mood and cognitive performance. In Study 4, performance and well-being were reported throughout the workday and at the end of the day, and heart rate and cortisol were measured. Under experimental conditions, gum was associated with higher alertness regardless of whether performance tasks were completed and altered sustained attention. Rate of chewing and subjective force of chewing did not alter mood but had some limited effects on attention. Chewing gum during the workday was associated with higher productivity and fewer cognitive problems, raised cortisol levels in the morning, and did not affect heart rate. The results emphasise that chewing gum can attenuate reductions in alertness, suggesting that chewing gum enhances worker performance. PMID:26075253

  19. Energy balance and expenditure while consuming guar gum at various fat intakes and ambient temperatures.

    PubMed

    Brown, J C; Livesey, G

    1994-12-01

    We devised a new model to evaluate whether dietary composition affects whole-body energy metabolism in rats. Dietary guar gum, but not corn starch, elevates both fecal energy excretion and energy expenditure. Neither ambient temperature (21 vs 28 degrees C) nor fat content of the basal diet (15% vs 33% metabolizable energy) has a marked effect on guar gum's thermogenic stimulus. Starch and guar gum each contribute 17.5 kJ/g to gross energy intake. This energy is fully available from the starch but guar gum contributes only 9-13 kJ/g to digestible energy intake on the low-fat diet (15% of energy), only 6 kJ/g to digestible energy on the higher-fat diet (33% of energy) (because of a fat-gum interaction), decreases urinary energy loss by 1.4-2.7 kJ/g gum, and elevates energy expenditure by 11.6-14.8 kJ/g. The thermogenic effect of the guar gum is highly reproducible. Several potential mechanisms to explain such elevated energy expenditure are considered. The model used to quantify the thermogenic stimulus is highly sensitive and could be applied to the trial of potentially thermogenic drugs as well as dietary ingredients. PMID:7985640

  20. Rheological Behavior of Xanthan Gum Solution Related to Shear Thinning Fluid Delivery for Subsurface Remediation

    SciTech Connect

    Zhong, Lirong; Oostrom, Martinus; Truex, Michael J.; Vermeul, Vincent R.; Szecsody, James E.

    2013-01-15

    Xanthan gum, a biopolymer, forms shear thinning fluids which can be used as delivery media to improve the distribution of remedial amendments injected into heterogeneous subsurface environments. The rheological behavior of the shear thinning solution needs to be known to develop an appropriate design for field injection. In this study, the rheological properties of xanthan gum solutions were obtained under various chemical and environmental conditions relevant to delivery of remedial amendments to groundwater. Higher xanthan concentration raised the absolute solution viscosity and increased the degree of shear thinning. Addition of remedial amendments (e.g., phosphate, sodium lactate, ethyl lactate) caused the dynamic viscosity of xanthan gum to decrease, but the solutions maintained shear-thinning properties. Use of simple salt (e.g. Na+, Ca2+) to increase the solution ionic strength also decreased the dynamic viscosity of xanthan and the degree of shear thinning, although the effect is a function of xanthan gum concentration and diminished as the xanthan gum concentration was increased. At high xanthan concentration, addition of salt to the solution increased dynamic viscosity. In the absence of sediments, xanthan gum solutions maintain their viscosity properties for months. However, xanthan gum solutions were shown to lose dynamic viscosity over a period of days to weeks when contacted with saturated site sediment. Loss of viscosity is attributed to physical and biodegradation processes.

  1. Improved welan gum production by Alcaligenes sp. ATCC31555 from pretreated cane molasses.

    PubMed

    Ai, Hongxia; Liu, Min; Yu, Pingru; Zhang, Shaozhi; Suo, Yukai; Luo, Ping; Li, Shuang; Wang, Jufang

    2015-09-20

    Welan gum production by Alcaligenes sp. ATCC31555 from cane molasses was studied in batch fermentation to reduce production costs and enhance gum production. The pretreatment of cane molasses, agitation speed and the addition of supplements were investigated to optimize the process. Sulfuric acid hydrolysis was found to be the optimal pretreatment, resulting in a maximum gum concentration of 33.5g/L, which is 50.0% higher than those obtained from the molasses' mother liquor. Agitation at 600rpm at 30°C and addition of 10% n-dodecane following fermentation for 36h increased the maximum gum production up to 41.0±1.41g/L, which is 49.1% higher than the greatest welan gum concentration in the literature so far. The welan gum product showed an acceptable molecular weight, similar rheological properties and better thermal stability to that obtained from glucose. These results indicate that cane molasses may be a suitable and inexpensive substrate for cost-effective industrial-scale welan gum production. PMID:26050885

  2. Study of algal biomass harvesting using cationic guar gum from the natural plant source as flocculant.

    PubMed

    Banerjee, Chiranjib; Ghosh, Sandipta; Sen, Gautam; Mishra, Sumit; Shukla, Pratyoosh; Bandopadhyay, Rajib

    2013-01-30

    Microalgae are small in size with negatively charged surface. They are usually stable in suspension culture and hard to flocculate. The present work emphasizes on the synthesis of cationic guar gum (CGG) by the introduction of quaternary amine groups onto the backbone of guar gum (GG) from N-(3-chloro-2-hydroxypropyl) trimethyl ammonium chloride (CHPTAC). The optimal dosage of the synthesized cationic guar gum is used to flocculate two different green algae viz. Chlorella sp. CB4 and Chlamydomonas sp. CRP7. PMID:23218353

  3. Photosensitivity of heterojunctions formed by deposition of gum on a layered III VI semiconductor

    NASA Astrophysics Data System (ADS)

    Drapak, S. I.; Kovalyuk, Z. D.

    2007-09-01

    The list of materials showing promise for the production of photosensitive structures is extended to include an organic material of biological origin known as gum. The current-voltage characteristics of hetero-junctions formed by a gum layer and a layered semiconductor (InSe, GaSe) are studied. An attempt is made to relate some spectral features of the relative quantum efficiency of the structures (for example, nonzero photosensitivity beyond the fundamental absorption edge of the semiconductor material) to the deformation interaction between the condensed gum layer and the layered III VI semiconductor surface.

  4. Ex vivo skin permeation and retention studies on chitosan-ibuprofen-gellan ternary nanogel prepared by in situ ionic gelation technique-a tool for controlled transdermal delivery of ibuprofen.

    PubMed

    Abioye, Amos Olusegun; Issah, Sureya; Kola-Mustapha, Adeola Tawakalitu

    2015-07-25

    The chemical potentials of drug-polymer electrostatic interaction have been utilized to develop a novel ternary chitosan-ibuprofen-gellan nanogel as controlled transdermal delivery tool for ibuprofen. The ternary nanogels were prepared by a combination of electrostatic nanoassembly and ionic gelation techniques. The electrostatic and hydrophobic interactions as well as hydrogen bonding between ibuprofen and chitosan were confirmed with FTIR, while DSC, TGA and SEM confirmed the physical state, thermal and morphological characteristics, respectively. The ex vivo delivery of ibuprofen onto and across the skin was evaluated based on system specific drug release parameters such as steady state permeation rate, permeability coefficient, permeability enhancement ratio, skin/gel partition coefficient, diffusion coefficient, lag time and release rate constant and mechanisms of release were determined using mathematical models. Interaction between ibuprofen and chitosan produced new spherical eutectic nanoconjugates with remarkable decrease in particle size of ibuprofen from 4580 (length-to-breadth aspect ratio) to a minimum of 14.15nm (324-times), and thermally stable amorphous characteristics. The nanogels exhibited significant elastic and pseudoplastic characteristics dictated by the concentration of chitosan with maximum swelling capacity of 775% w/w at 6.55mM chitosan compared with 281.16 and 506.50% for plain gellan and control ibuprofen hydrogel, respectively. Chitosan enhanced the skin penetration, permeability and the rate of transdermal release of ibuprofen by a factor of 4, dictated by the extent of ibuprofen-chitosan ionic interaction and its concentration. The major mechanism of ibuprofen release through the pig skin was drug diffusion however drug partition and matrix erosion also occurred. It was evident that ternary nanogels are novel formulations with potential application in controlled transdermal delivery of ibuprofen. PMID:25997660

  5. Alginate/cashew gum nanoparticles for essential oil encapsulation.

    PubMed

    de Oliveira, Erick F; Paula, Haroldo C B; de Paula, Regina C M

    2014-01-01

    Alginate/cashew gum nanoparticles were prepared via spray-drying, aiming at the development of a biopolymer blend for encapsulation of an essential oil. Nanoparticles were characterized regarding to their hydrodynamic volume, surface charge, Lippia sidoides essential oil content and release profile, in addition to being analyzed by infrared spectroscopy (FT-IR), thermal analysis (TGA/DSC) and X-ray diffractometry. Nanoparticles in solution were found to have averaged sizes in the range 223-399 nm, and zeta potential values ranging from -30 to -36 mV. Encapsulated oil levels varied from 1.9 to 4.4% with an encapsulation efficiency of up to 55%. The in vitro release profile showed that between 45 and 95% of oil was released within 30-50h. Kinetic studies revealed that release pattern follow a Korsmeyer-Peppas mechanism. PMID:24077112

  6. Flocculation characteristics and biodegradation studies of Gum ghatti based hydrogels.

    PubMed

    Mittal, H; Mishra, Shivani B; Mishra, A K; Kaith, B S; Jindal, R

    2013-07-01

    Biodegradable flocculants of Gum ghatti (Gg) with acrylamide (AAm) were prepared through graft co-polymerization technique using potassium persulphate (KPS)-ascorbic acid (ABC) redox pair as initiator and N,N'-methylene-bis-acrylamide (MBA) as a crosslinker. Gg-cl-poly(AAm) was found to exhibit pH and temperature responsive swelling behavior. Maximum flocculation efficiency of Gg-cl-poly(AAm) was observed with 15 mg L(-1) polymer dose in acidic medium at 50°C. Biodegradation studies of Gg and Gg-cl-poly(AAm) were done using composting method. Gg was found to degrade within 20 days, whereas, Gg-cl-poly(AAm) was found to degrade 88.18% within 60 days. Different stages of bio-degradation were characterized through FT-IR and SEM techniques. PMID:23541560

  7. Study of the reaction of grafting acrylamide onto xanthan gum.

    PubMed

    Maia, Ana M S; Silva, Hugo V M; Curti, Priscila S; Balaban, Rosangela C

    2012-10-01

    The present study aimed to study the reaction conditions of grafting of acrylamide on xanthan gum. It was analyzed the influence of reaction conditions, mainly type of initiator activation, initiator concentration and initiator/acrylamide ratio, on graft parameters and copolymer properties. Potassium persulfate was employed as an initiator and heating or N,N,N',N'-tetramethylethylenediamine was used to activate the initiator. Reaction time and initiator concentration were varied and final values for grafting percentage and grafting efficiency were the same for both methods, whereas speed in reaching these values differs from one technique to another. We found that reaction time was inversely proportional to intrinsic viscosity, likely due to main chain degradation promoted by potassium persulfate (KPS); furthermore, the increasing in the KPS concentration lowers grafting percentage, acrylamide conversion and chain degradation, possibly as a result of O(2) formation at high KPS concentrations. PMID:22840001

  8. A radio-polarisation and rotation measure study of the Gum Nebula and its environment

    E-print Network

    Purcell, C R; Sun, X H; Carretti, E; Bernardi, G; Haverkorn, M; Kesteven, M J; Poppi, S; Schnitzeler, D H F M; Staveley-Smith, L

    2015-01-01

    The Gum Nebula is 36 degree wide shell-like emission nebula at a distance of only 450 pc. It has been hypothesised to be an old supernova remnant, fossil HII region, wind-blown bubble, or combination of multiple objects. Here we investigate the magneto-ionic properties of the nebula using data from recent surveys: radio-continuum data from the NRAO VLA and S-band Parkes All Sky Surveys, and H-alpha data from the Southern H-Alpha Sky Survey Atlas. We model the upper part of the nebula as a spherical shell of ionised gas expanding into the ambient medium. We perform a maximum-likelihood Markov chain Monte-Carlo fit to the NVSS rotation measure data, using the H-halpha data to constrain average electron density in the shell $n_e$. Assuming a latitudinal background gradient in RM we find $n_e=1.3^{+0.4}_{-0.4} {\\rm cm}^{-3}$, angular radius $\\phi_{\\rm outer}=22.7^{+0.1}_{-0.1} {\\rm deg}$, shell thickness $dr=18.5^{+1.5}_{-1.4} {\\rm pc}$, ambient magnetic field strength $B_0=3.9^{+4.9}_{-2.2} \\mu{\\rm G}$ and warm ...

  9. Compounds from Gum Ammoniacum with Acetylcholinesterase Inhibitory Activity

    PubMed Central

    Adhami, Hamid-Reza; Lutz, Johannes; Kählig, Hanspeter; Zehl, Martin; Krenn, Liselotte

    2013-01-01

    The use of herbal medicinal preparations in dementia therapy has been studied based on experience from traditional medicine. A dichloromethane extract of gum ammoniacum, the gum-resin from Dorema ammoniacum D. Don had shown acetylcholinesterase (AChE) inhibitory activity in a previous study. The aim of this study was the isolation and characterization of the active compounds from this resin. The extract was investigated by a respective colorimetric microplate assay and the active zones were identified via TLC bioautography and isolated using several chromatographic techniques. The structures of the active components were characterized by one- and two-dimensional 1H and 13C NMR spectroscopy and mass spectrometry as (2?S,5?S)-2?-ethenyl-5?-(3-hy-droxy-6-methyl-4-oxohept-5-en-2-yl)-7-methoxy-2?-methyl-4H-spiro[chromene-3,1?-cyclopentane]-2,4-dione (1), which is an analogue of doremone A and a new natural compound, and as (2?S,5?R)-2?-ethenyl-5?-[(2R,4R)-4-hydroxy-6-methyl-3-oxohept-5-en-2-yl]-7-methoxy-2?-methyl-4H-spiro[chromene-3,1?-cyclo-pentane]-2,4-dione (2 = doremone A), (4E,8E)-1-(2,4-dihydroxyphenyl)-5,9,13-trimethyltetradeca-4,8,12-trien-1-one (3 = dshamirone), and 4,7-dihydroxy-3-[(2E,6E)-3,7,11-trimethyldodeca-2,6,10-trien-1-yl]-2H-chromen-2-one (4 = am-moresinol). Dshamirone turned out to be the most active compound with an IC50 value for AChE inhibitory activity of 23.5 ?M, whereas the other substances showed weak activity. The concentrations of the analytes in the resin were determined by HPLC as 3.1%, 4.6%, 1.9%, and 9.9%, respectively. PMID:24106674

  10. Application and Characterization of Gum from Bombax buonopozense Calyxes as an Excipient in Tablet Formulation.

    PubMed

    Ngwuluka, Ndidi C; Kyari, Jehu; Taplong, John; Uwaezuoke, Onyinye J

    2012-01-01

    This study was undertaken to explore gum from Bombax buonopozense calyxes as a binding agent in formulation of immediate release dosage forms using wet granulation method. The granules were characterized to assess the flow and compression properties and when compressed, non-compendial and compendial tests were undertaken to assess the tablet properties for tablets prepared with bombax gum in comparison with those prepared with tragacanth and acacia gums. Granules prepared with bombax exhibited good flow and compressible properties with angle of repose 28.60°, Carr's compressibility of 21.30% and Hausner's quotient of 1.27. The tablets were hard, but did not disintegrate after one hour. Furthermore, only 52.5% of paracetamol was released after one hour. The drug release profile followed zero order kinetics. Tablets prepared with bombax gum have the potential to deliver drugs in a controlled manner over a prolonged period at a constant rate. PMID:24300296

  11. ISO/GUM UNCERTAINTIES AND CIAAW (UNCERTAINTY TREATMENT FOR RECOMMENDED ATOMIC WEIGHTS AND ISOTOPIC ABUNDANCES)

    SciTech Connect

    HOLDEN,N.E.

    2007-07-23

    The International Organization for Standardization (ISO) has published a Guide to the expression of Uncertainty in Measurement (GUM). The IUPAC Commission on Isotopic Abundance and Atomic Weight (CIAAW) began attaching uncertainty limits to their recommended values about forty years ago. CIAAW's method for determining and assigning uncertainties has evolved over time. We trace this evolution to their present method and their effort to incorporate the basic ISO/GUM procedures into evaluations of these uncertainties. We discuss some dilemma the CIAAW faces in their present method and whether it is consistent with the application of the ISO/GUM rules. We discuss the attempt to incorporate variations in measured isotope ratios, due to natural fractionation, into the ISO/GUM system. We make some observations about the inconsistent treatment in the incorporation of natural variations into recommended data and uncertainties. A recommendation for expressing atomic weight values using a tabulated range of values for various chemical elements is discussed.

  12. The Quantitative Determination of Butylated Hydroxytoluene in Chewing Gum Using GC--MS

    ERIC Educational Resources Information Center

    Witter, A. E.

    2005-01-01

    The experiment to measure concentration of Photophysical Characterization(BHT) and determine percent recovery in chewing gum is described. The results demonstrated that over time, the concentration of BHT in the extract decreased owing to aerial oxidation.

  13. 78 FR 33354 - Xanthan Gum From Austria: Final Determination of Sales at Less Than Fair Value

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-04

    ...Determination of Sales at Less Than Fair Value and Postponement of Final Determination...Administration, concerning, Less Than Fair Value Investigation of Xanthan Gum from...including examination of relevant accounting and production records and...

  14. Prebiotic Properties of Yeast Cell Wall Mannanoligosaccharides and Guar Gum Galactomannans in Starting Broilers 

    E-print Network

    Kakani, Radhika

    2013-12-04

    Two studies were designed to evaluate the growth promoting and prebiotic properties of Yeast Cell Wall (YCW) containing mannanoligosaccharides (MOS) and guar gum galactomannans in starting broilers. In study one, the effects of different sources...

  15. Origin and thermodynamic properties of the instability of synthetic azo colorants in gum arabic solutions.

    PubMed

    Fang, Yapeng; Al-Assaf, Saphwan; Sakata, Makoto; Phillips, Glyn O; Schultz, Matthias; Monnier, Vivianne

    2007-10-31

    The instability of some industrially important synthetic azo colorants, including sunset yellow, azorubine, and allura red, toward gum arabic in aqueous solution has been a long-standing problem for the beverage and confectionery industries. Precipitation of these colorants causes the deterioration of product appearance and properties. This work examines the origin and nature of the problem by analysis of the precipitate and thermodynamic studies of gum arabic-colorant interactions using isothermal titration calorimetry (ITC). The presence of divalent alkaline earth metals in gum arabic samples, that is, calcium and magnesium, is shown to be responsible for the precipitation of the azo colorants. There is no direct interaction between gum arabic and the colorant molecules, and the precipitate is formed likely due to the mediation/bridging by the divalent cations. The thermodynamic knowledge gained from the ITC studies, for example, binding affinity, stoichiometry, and enthalpy, enables interpretation of many industrial observations. PMID:17910512

  16. Xylitol carryover effects on salivary mutans streptococci after 13 months of chewing xylitol gum.

    PubMed

    Shinga-Ishihara, C; Nakai, Y; Milgrom, P; Söderling, E; Tolvanen, M; Murakami, K

    2012-01-01

    To assess mutans streptococci (MS) during xylitol gum chewing (mean 3.8 g/day, 2.9 times/day) for 13 months and then for 15 months after the intervention, Japanese mothers with high salivary MS were randomized into two groups: xylitol gum (n = 56) and no gum (n = 51). The proportion of low MS levels was highest at 3 months of consumption (48.8%), but was significantly lower compared to baseline at the end of the intervention (p < 0.001). MS levels did not change during the postintervention period. The data suggest that in the xylitol group 23.3% showed persistent carryover effects by xylitol gum chewing in the postintervention period. PMID:22890503

  17. Production of vermifertilizer from guar gum industrial wastes by using composting earthworm Perionyx sansibaricus (Perrier)

    Microsoft Academic Search

    Surendra Suthar

    2007-01-01

    Efforts have been made to convert the guar gum industrial waste into a value-added product, by employing a new earthworm species\\u000a for vermicomposting e.g. Perionyx sansibaricus (Perrier) (Megascolecidae), under laboratory conditions. Industrial lignocellulosic waste was amended with other organic\\u000a supplements (saw dust and cow dung); and three types of vermibeds were prepared: guar gum industrial waste + cow dung + saw\\u000a dust in 40:

  18. The postoperative use of wound adhesives. Gum mastic versus benzoin, USP.

    PubMed

    Lesesne, C B

    1992-11-01

    Our results, combined with the work of previous authors, show that gum mastic not only offers superior adhesive qualities compared with benzoin, USP but also has a lower incidence of postoperative contact dermatitis and subsequent skin discoloration. In light of the widespread use of surgical adhesives, this study is important in documenting the low incidence of complications and the advantages of gum mastic compared with benzoin, USP. PMID:1430556

  19. Mechanisms of antiprostate cancer by gum mastic: NF-?B signal as target

    Microsoft Academic Search

    Mei-lan He; Ang Li; Chun-su Xu; Shun-li Wang; Meng-jie Zhang; Hua Gu; Yao-qin Yang; Hui-hong Tao

    2007-01-01

    Aim:To study the effect of gum mastic, a natural resin, on the proliferation of androgen-independent prostate cancer PC-3 cells, and further investigate the mechanisms involved in this regulatory system, taking nuclear factor ?B (NF-?B) signal as the target.Methods:3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and a flow cytometer were used to detect the effect of gum mastic on the proliferation of PC-3 cells.

  20. Injectivity improvement of xanthan gums by enzymes: Process design and performance evaluation

    SciTech Connect

    Kohler, N.; Lonchamp, D.; Thery, M.

    1987-07-01

    Injectability and filterability of xanthan gum dispersions, especially in hard brines, can be considerably improved by successive use of cellulase and alkaline protease enzyme treatments. A thorough optimization of the different parameters controlling enzymatic activity has led to an original clarification process. Improvements observed in flow behavior of treated xanthan gum solutions through reservoir rocks is the result of almost complete elimination of both insoluble bacterial cells and microgels.

  1. Strong Band-Edge Emission from ZnS Quantum Dots Stabilized by Gum Arabic

    NASA Astrophysics Data System (ADS)

    Hatim, Dirar Mohamed El-Khair

    2008-12-01

    ZnS quantum dots (QDs), prepared by soft-condensation, exhibit robust structure of a quantum size equal 3.13 nm mediated two-dimensional gum Arabic surfactant as characterized by scan tunnelling microscope (STM). Strong blue-shifted absorption and emission bands are depicted by optical characterization even for the sample stored under ambient condition for two weeks. These enhancements can be attributed to the completely passivated surface trap states by Gum Arabic.

  2. Mechanical properties of gels formed by mixtures of mucilage gum ( Opuntia ficus indica) and carrageenans

    Microsoft Academic Search

    L. Medina-Torres; E. Brito-De La Fuente; B. Torrestiana-Sanchez; S. Alonso

    2003-01-01

    The mechanical properties of gels formed by either mixtures of mucilage gum from Opuntia ficus indica and ?-carrageenan or i-carrageenan have been examined using dynamic shear and uniaxial compression measurements. A total polymer concentration of 2% (w\\/w) was used, the proportion of mucilage gum varying from 0 to 80% (w\\/w) and KCl or CaCl2 in the range from 12 to

  3. Microwave-promoted hydrolysis of plant seed gums on alumina support

    Microsoft Academic Search

    Vandana Singh; Ashutosh Tiwari; Premlata Kumari; Stuti Tiwari

    2006-01-01

    Using a catalytic amount of potassium persulfate (1.48×10?4M), eight different seed gums were fully hydrolyzed on alumina support under microwave irradiation. The hydrolysis time varied between 1.33 and 2.33min depending upon the seed gum structure. The used solid support could be easily separated from the hydrolyzates and recycled. However, under microwave field in an aqueous medium, the same amount of

  4. Effects of nicotine-containing chewing gum on oral soft and hard tissues: A clinical study.

    PubMed

    Christen, A G; Beiswanger, B B; Mallatt, M E; Tomich, C E; Drook, C A; McDonald, J L; Olson, B L; Stookey, G K

    1985-01-01

    A double-blind clinical trial was conducted to determine whether the use of a chewing gum containing 2.0 mg nicotine (as an adjunct to a stop-smoking program) had any effects upon oral health. A total of 193 adults who smoked cigarettes volunteered with informed consent, were given routine dental prophylaxes, and were examined for the presence of plaque, stained pellicle, gingivitis, calculus, and general oral pathosis. The subjects were then randomly assigned to use either a nicotine-containing or a placebo chewing gum. After 15 weeks the subjects were recalled and re-examined. Smoking cessation was determined through questionnaire and analysis of the carbon monoxide content of alveolar air. At the completion of the study, 79 subjects had used the placebo gum and 78 had used the nicotine gum. Data analysis indicated that the nicotine chewing gum had no significant influence on any of the oral health parameters graded, as compared to the placebo gum. The continuation of smoking, however, was associated with significant increases in gingivitis and calculus rates. PMID:3919352

  5. Water adsorption isotherms of carboxymethyl cellulose, guar, locust bean, tragacanth and xanthan gums.

    PubMed

    Torres, María D; Moreira, Ramón; Chenlo, Francisco; Vázquez, María J

    2012-06-20

    Water adsorption isotherms of carboxymethyl cellulose (CMC), guar gum (GG), locust bean gum (LBG), tragacanth gum (TG) and xanthan gum (XG) were determined at different temperatures (20, 35, 50, and 65°C) using a gravimetric method. Several saturated salt solutions were selected to obtain different water activities in the range from 0.09 to 0.91. Water adsorption isotherms of tested hydrocolloids were classified like type II isotherms. In all cases, equilibrium moisture content decreased with increasing temperature at each water activity value. Three-parameter Guggenheim-Anderson-de Boer (GAB) model was employed to fit the experimental data in the water activity range and statistical analysis indicated that this model gave satisfactory results. CMC and GG were the most and the least hygroscopic gums, respectively. Sorption heats decreased with increasing moisture content. Monolayer moisture content evaluated with GAB model was consistent with equilibrium conditions of maximum stability calculated from thermodynamic analysis of net integral entropy. Values of equilibrium relative humidity at 20°C are proposed to storage adequately the tested gums. PMID:24750763

  6. The effect of mastic gum on Helicobacter pylori: a randomized pilot study.

    PubMed

    Dabos, K J; Sfika, E; Vlatta, L J; Giannikopoulos, G

    2010-03-01

    Our aim was to study the effect of pure mastic gum on Helicobacter pylori (H. pylori) eradication in patients suffering from an H. pylori infection Fifty two patients were randomized to receive either 350mg three times a day (tid) of pure mastic gum for 14 days (Group A), or 1,05g tid of pure mastic gum (Group B) for 14 days, or pantoprazole 20mg twice a day (bd) plus pure mastic gum 350mg tid for 14 days (Group C) or pantoprazole 20mg bd plus amoxicillin 1g bd plus clarithromycin 500mg bd for 10 days (Group D). All patients harboured H. pylori before entering the study and that was confirmed by a (13)C urea breath test (UBT). H. pylori eradication was tested by a UBT 5 weeks after completion of the eradication regime. Eradication of H. pylori was confirmed in 4/13 patients in Group A and in 5/13 in Grour B. No patient in Group C achieved eradication whereas 10/13 patients in Group D had a negative UBT. There were no statistically significant differences in mean UBT values in Groups A, B, C although there was a trend in Group A (p=0.08) and in Group B (p=0.064). The difference was significant in Group D (p=0.01). All patients tolerated mastic gum well and no serious adverse events were reported. Mastic gum has bactericidal activity on H. pylori in vivo. PMID:19879118

  7. Antihyperglycemic and antihyperlipidemic effects of guar gum on streptozotocin-induced diabetes in male rats

    PubMed Central

    Saeed, Samarghandian; Mosa-Al-Reza, Hadjzadeh; Fatemeh, Amin Nya; Saeideh, Davoodi

    2012-01-01

    Background: Herbal medicine is widely used in the treatment of diseases like diabetes mellitus. We investigated the effects of guar gum in diabetic rats for the reduction of the risk of diabetes and cardiovascular disease. Dietary pattern emphasizing foods high in complex carbohydrates and fiber are associated with low blood glucose and cholesterol levels. Materials and Methods: Diet containing 0%, 5%, 10% and 20% (w/w) guar gum was fed to diabetic rats for 28 days. Blood serum glucose, triglycerides, cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol levels, atherogenic index levels, body weights and food intake were monitored at 0, 7.14 and 28 days after induction of diabetes. Results: In spite of the fact that diabetes elevated blood lipids in all rats after 14 days, the guar gum diet significantly decreased the serum concentration of cholesterol, triacylglicerols and LDL-C and atherogenic index. The most significant result in this study was the reduction of blood glucose in diabetic rats treated with the guar gum diet after 28 days versus non- and glibenclamide-treated rats. The gum promoted a general improvement in the condition of the diabetic rats in body weight and food intake in comparison with nontreated rats. Conclusion: The results of this research suggest that guar gum was significantly effective in comparison with glibenclamide in the treatment of hyperlipidemia and hyperglycemia in diabetes rats. Therefore, it may be suggested as a reliable fiber in diabetic regimes in diabetic patients. PMID:22438666

  8. Effect of guar gum on glucose and lipid metabolism in white sea bream Diplodus sargus.

    PubMed

    Enes, P; Pousão-Ferreira, P; Salmerón, C; Capilla, E; Navarro, I; Gutiérrez, J; Oliva-Teles, A

    2013-04-01

    The aim of this study was to assess the role of soluble non-starch polysaccharide (guar gum) on white sea bream Diplodus sargus, glucose and lipid metabolism. A control diet was formulated to contain 40 % crude protein, 14 % crude lipids and 35 % pregelatinized maize starch, and three other diets were formulated similar to the control diet except for guar gum, which was included at 4 % (diet GG4), 8 % (diet GG8) or 12 % (diet GG12). Diets were fed to the fish for 9 weeks on a pair-feeding scheme. Guar gum had no effect on growth performance, feed efficiency, glycaemia, cholesterolaemia and plasma triacylglyceride levels. Hepatic glucokinase and pyruvate kinase activities, liver glycogen content and liver insulin-like growth factor-I gene expression were not affected by dietary guar gum, while fructose-1,6-bisphosphatase activity was lower in fish fed guar gum-supplemented diets. Hepatic glucose-6-phosphate dehydrogenase activity was higher in fish fed diets GG4 and GG8 than in the control group. Overall, data suggest that in contrast to mammals guar gum had no effect on white sea bream glucose utilization and in lowering plasma cholesterol and triacylglyceride levels. However, it seems to contribute to lower endogenous glucose production. PMID:22763699

  9. Xanthomonas campestris pv. campestris gum Mutants: Effects on Xanthan Biosynthesis and Plant Virulence

    PubMed Central

    Katzen, Federico; Ferreiro, Diego U.; Oddo, Cristian G.; Ielmini, M. Verónica; Becker, Anke; Pühler, Alfred; Ielpi, Luis

    1998-01-01

    Xanthan is an industrially important exopolysaccharide produced by the phytopathogenic, gram-negative bacterium Xanthomonas campestris pv. campestris. It is composed of polymerized pentasaccharide repeating units which are assembled by the sequential addition of glucose-1-phosphate, glucose, mannose, glucuronic acid, and mannose on a polyprenol phosphate carrier (L. Ielpi, R. O. Couso, and M. A. Dankert, J. Bacteriol. 175:2490–2500, 1993). A cluster of 12 genes in a region designated xpsI or gum has been suggested to encode proteins involved in the synthesis and polymerization of the lipid intermediate. However, no experimental evidence supporting this suggestion has been published. In this work, from the biochemical analysis of a defined set of X. campestris gum mutants, we report experimental data for assigning functions to the products of the gum genes. We also show that the first step in the assembly of the lipid-linked intermediate is severely affected by the combination of certain gum and non-gum mutations. In addition, we provide evidence that the C-terminal domain of the gumD gene product is sufficient for its glucosyl-1-phosphate transferase activity. Finally, we found that alterations in the later stages of xanthan biosynthesis reduce the aggressiveness of X. campestris against the plant. PMID:9537354

  10. Gum arabic modified Fe3O4 nanoparticles cross linked with collagen for isolation of bacteria

    PubMed Central

    2010-01-01

    Background Multifunctional magnetic nanoparticles are important class of materials in the field of nanobiotechnology, as it is an emerging area of research for material science and molecular biology researchers. One of the various methods to obtain multifunctional nanomaterials, molecular functionalization by attaching organic functional groups to nanomagnetic materials is an important technique. Recently, functionalized magnetic nanoparticles have been demonstrated to be useful in isolation/detection of dangerous pathogens (bacteria/viruses) for human life. Iron (Fe) based material especially FePt is used in the isolation of ultralow concentrations (< 102 cfu/ml) of bacteria in less time and it has been demonstrated that van-FePt may be used as an alternative fast detection technique with respect to conventional polymerase chain reaction (PCR) method. However, still further improved demonstrations are necessary with interest to biocompatibility and green chemistry. Herein, we report the synthesis of Fe3O4 nanoparticles by template medication and its application for the detection/isolation of S. aureus bacteria. Results The reduction of anhydrous Iron chloride (FeCl3) in presence of sodium borohydride and water soluble polyelectrolyte (polydiallyldimethyl ammonium chloride, PDADMAC) produces black precipitates. The X-ray diffraction (XRD), XPS and TEM analysis of the precipitates dried at 373 K demonstrated the formation of nanocrystalline Fe3O4. Moreover, scanning electron microscopy (SEM) showed isolated staphylococcous aureus (S. aureus) bacteria at ultralow concentrations using collagen coated gum arabic modified iron oxide nanoparticles (CCGAMION). Conclusion We are able to synthesize nanocrystalline Fe3O4 and CCGAMION was able to isolate S. aureus bacteria at 8-10 cfu (colony forming units)/ml within ~3 minutes. PMID:21159158

  11. Effect of Chewing Xylitol Containing and Herbal Chewing Gums on Salivary Mutans Streptococcus Count among School Children

    PubMed Central

    Chavan, Sangeeta; Lakashminarayan, Nagesh; Kemparaj, Umesh

    2015-01-01

    Background: The present study aims to assess and compare the reduction in salivary Mutans Streptococci counts after chewing Xylitol, herbal and placebo gums among high school children. Methods: The study was conducted among 72 school children (12–15 years) from 3 randomly selected schools (blocks). Xylitol, herbal and placebo gums were randomly allocated to 3 blocks. Subjects were instructed to chew one pellet four times a day for 21 days. The mean reduction in salivary Streptococcus mutans count was assessed. Results: The 100% Xylitol sweetened chewing gum “Xylitol”has shown statistically significant reduction in salivary Mutans Streptococci colony forming units at the end of 21 days (P < 0.01). The reduction was not statistically significant in herbal and placebo chewing gum. Conclusions: Hundred percentage Xylitol sweetened chewing gum was found to be more effective in reducing salivary Mutans Streptococci count when compared to herbal and placebo chewing gums.

  12. A Study of the Cometary Globules in the GUM Nebula

    NASA Astrophysics Data System (ADS)

    Sridharan, T. K.

    1994-09-01

    The first part of the thesis deals with the development of a wide-band mechanically tuned local oscillator using the Gunn diode for use with the 10.4m millimeter-wave radio telescope at the Raman Research Institute. This provides sufficient power to efficiently operate two cryogenic Schottky mixers (dual polarisation) and tunes over the frequency range 75-115 GHz covering most of the 3-mm atmospheric transmission window (W-band). Rotational transitions of many astrophysically important molecules including CO fall in this range. A study of the cometary globules(CGs) in the Gum Nubula forms the second part. The CGs are characterised by compact, dusty heads with long faintly luminous tails extending on one side and narrow bright rims on the other side. There exists a significant population of such CGs in the Gum Nebula, distributed over a region ~80 parsec in radius with their tails pointing away from an apparent common center. Some of the heads have embedded young stars. In the region bounded by the CGs there are a few massive hot stars including zeta Puppis believed to be the most luminous star in the southern sky. It has been suspected that the morphological appearance of the CGs may be due to the influence of these stars. In order to understand the kinematics and the origin of the system, a study was undertaken using the first rotational transition of the carbon monoxide molecule. The study consisted of ^12CO observations of the heads and the tails of the CGs. In addition, the Globule No.22 was mapped in both ^12CO and ^13CO. An analysis of this data has led to the following findings: 1. The system of CGs is expanding with respect to a common morphological center at ~12 kms^-1. The expansion age is ~6 Myr. 2. Some of the tails observed show systematic velocity gradients. If the tails were formed due to the elongation resulting from these velocity gradients then the estimated stretching age is ~3 Myr. In order to clarify if externally triggered star formation is going on in this region, an analysis of the locations of the embedded young stellar objects (YSOs, identified from the Infra-Red Astronomy Satellite data) in the dark clouds in the Gum-Vela region was undertaken. This study has shown that the YSOs have a statistically significant tendency to fall on the sides of dark clouds facing the morphological center rather than the far sides, supporting external triggering. From the above analysis we come to the following conclusions: 1. The rough agreement between the expansion age and the tail-stretching age suggests a common origin for the expansion and the formation of the tails. The presence of young stars of comparable ages in the heads of some of the globules suggests that the processes responsible for the expansion may have also triggered star formation in them. 2. The radiation pressure from the hot stars in the central region or the stellar winds from them cannot account for the momentum of the expanding globules. It is more likely that the rocket effect arising out of the heating and the consequent anisotropic ablation of the globules supplied the necessary momentum. From the space motion of the star zeta Puppis we suggest that it had a massive companion which exploded as a supernova half a million years ago. The combined effect of the ultra-violet radiation and the stellar wind from this binary as well as from other stars in the neighbourhood significantly affected the parent molecular cloud in which they formed. This resulted in much of the molecular material in the vicinity being blown away except the numerous regions of enhanced density (condensations) in the original molecular cloud. Continued effect of the radiation and stellar winds resulted in these condensations being set in motion, as well as developing cometary tails. (SECTION: Dissertation Summary)

  13. Study of water vapour permeability of protein and gum-based edible films by a photothermal method

    NASA Astrophysics Data System (ADS)

    Tomás, S. A.; Saavedra, R.; Cruz, A.; Pedroza-Islas, R.; San Martín, E.

    2005-06-01

    The water vapour permeability of protein and gum-based edible films was studied by means of a photothermal method. The films were prepared with two basic ingredients, whey protein concentrate and mesquite gum, according to the proportions 75:25, 50:50, 25:75, and 0:100 (weight:weight). The water vapour diffusion coefficient of the analyzed films was found within the interval 0.37 × 10-6 to 2.04 × 10-6 cm^2/s, increasing linearly by increasing the mesquite gum composition in the films. The incorporation of mesquite gum in films produces less effective moisture barriers due to its highly hydrophilic property.

  14. Magnetism

    NSDL National Science Digital Library

    University Corporation for Atmospheric Research Windows to the Universe team

    2007-12-12

    This webpage is part of the University Corporation for Atmospheric Research (UCAR) Windows to the Universe program. It describes the nature and configuration of magnetic fields, which are the result of moving electric charges, including how they cause magnetic objects to orient themselves along the direction of the magnetic force points, which are illustrated as lines. Magnetic field lines by convention point outwards at the north magnetic pole and inward at the south magnetic pole. The site features text, scientific illustrations and an animation. Text and vocabulary are selectable for the beginning, intermediate, or advanced reader.

  15. The nearby Galaxy structure toward the Vela Gum nebula

    E-print Network

    Giorgi, E E; Perren, G I; Vázquez, R A

    2015-01-01

    We report on $UBVI$ photometry and spectroscopy for MK classification purposes carried out in the fields of five open clusters projected against the Vela Gum in the Third Galactic Quadrant of the Galaxy. They are Ruprecht 20, Ruprecht 47, Ruprecht 60, NGC 2660 and NGC 2910. We could improve/confirm the parameters of these objects derived before. The spectroscopic parallax method has been applied to several stars located in the fields of four out of the five clusters to get their distances and reddenings. With this method we found two blue stars in the field of NGC 2910 at distances that make them likely members of Vela OB1 too. Also, projected against the fields of Ruprecht 20 and Ruprecht 47 we have detected other young stars favoring not only the existence of Puppis OB1 and OB2 but conforming a young stellar group at $\\sim1$ kpc from the Sun and extending for more than 6 kpc outward the Galaxy. If this is the case, there is a thickening of the thin Galactic disk of more than 300 pc at just 2-3 kpc from the ...

  16. The effect of chewing xylitol gum on the plaque and saliva levels of Streptococcus mutans.

    PubMed

    Loesche, W J; Grossman, N S; Earnest, R; Corpron, R

    1984-04-01

    Eating foods containing sucrose between meals can be highly cariogenic. The use of sucrose substitutes that provide the hedonistic appeal of sucrose, yet are not fermented by the plaque flora to the low pHs that are associated with caries, is a reasonable approach to caries control. Xylitol, a sweet-tasting pentitol, has been reported to cause about an 80% reduction in caries increment when chewed in a gum. The present investigation was designed to determine whether the chewing of xylitol gums affected the salivary and plaque levels of S mutans and lactobacilli. The chewing of xylitol gums for four weeks caused a significant reduction in saliva levels and plaque proportions of S mutans compared with pretreatment values. The levels were also significantly reduced to values obtained by chewing either sorbitol or fructose sweetened gum. The chewing of various gums had no significant effect on the proportions of lactobacilli in the plaque. These findings suggested that the small amounts of xylitol used (about 5 gm) resulted in a suppression of S mutans. PMID:6427315

  17. Bayesian uncertainty analysis compared with the application of the GUM and its supplements

    NASA Astrophysics Data System (ADS)

    Elster, Clemens

    2014-08-01

    The Guide to the Expression of Uncertainty in Measurement (GUM) has proven to be a major step towards the harmonization of uncertainty evaluation in metrology. Its procedures contain elements from both classical and Bayesian statistics. The recent supplements 1 and 2 to the GUM appear to move the guidelines towards the Bayesian point of view, and they produce a probability distribution that shall encode one's state of knowledge about the measurand. In contrast to a Bayesian uncertainty analysis, however, Bayes' theorem is not applied explicitly. Instead, a distribution is assigned for the input quantities which is then ‘propagated’ through a model that relates the input quantities to the measurand. The resulting distribution for the measurand may coincide with a distribution obtained by the application of Bayes' theorem, but this is not true in general. The relation between a Bayesian uncertainty analysis and the application of the GUM and its supplements is investigated. In terms of a simple example, similarities and differences in the approaches are illustrated. Then a general class of models is considered and conditions are specified for which the distribution obtained by supplement 1 to the GUM is equivalent to a posterior distribution resulting from the application of Bayes' theorem. The corresponding prior distribution is identified and assessed. Finally, we briefly compare the GUM approach with a Bayesian uncertainty analysis in the context of regression problems.

  18. Structure and Mechanism of GumK, a Membrane-Associated Glucuronosyltransferase

    SciTech Connect

    Barreras, M.; Salinas, S; Abdian, P; Kampel, M; Lelpi, L

    2008-01-01

    Xanthomonas campestris GumK (?-1,2-glucuronosyltransferase) is a 44-kDa membrane-associated protein that is involved in the biosynthesis of xanthan, an exopolysaccharide crucial for this bacterium's phytopathogenicity. Xanthan also has many important industrial applications. The GumK enzyme is the founding member of the glycosyltransferase family 70 of carbohydrate-active enzymes, which is composed of bacterial glycosyltransferases involved in exopolysaccharide synthesis. No x-ray structures have been reported for this family. To better understand the mechanism of action of the bacterial glycosyltransferases in this family, the x-ray crystal structure of apo-GumK was solved at 1.9A resolution. The enzyme has two well defined Rossmann domains with a catalytic cleft between them, which is a typical feature of the glycosyltransferase B superfamily. Additionally, the crystal structure of GumK complexed with UDP was solved at 2.28A resolution. We identified a number of catalytically important residues, including Asp157, which serves as the general base in the transfer reaction. Residues Met231, Met273, Glu272, Tyr292, Met306, Lys307, and Gln310 interact with UDP, and mutation of these residues affected protein activity both in vitro and in vivo. The biological and structural data reported here shed light on the molecular basis for donor and acceptor selectivity in this glycosyltransferase family. These results also provide a rationale to obtain new polysaccharides by varying residues in the conserved ?/?/? structural motif of GumK.

  19. Development of eco-friendly submicron emulsions stabilized by a bio-derived gum.

    PubMed

    Pérez-Mosqueda, Luis María; Ramírez, Pablo; Trujillo-Cayado, Luis Alfonso; Santos, Jenifer; Muñoz, José

    2014-11-01

    Many traditional organic solvents are being gradually replaced by ecofriendly alternatives. D-Limonene is a terpenic (bio)-solvent that fulfils the requirements to be considered a green solvent. D-Limonene sub-micron emulsions suffer from Ostwald ripening destabilization. In this study, we examined the influence of the addition of a natural gum (rosin gum) to D-limonene in order to prevent Ostwald ripening. This contribution deals with the study of emulsions formulated with a mixture of D-limonene and rosin gum as dispersed phase and Pluronic PE9400 as emulsifier. The procedure followed for the development of these formulations was based on the application of product design principles. This led to the optimum ratio rosin gum/D-limonene and subsequently to the optimum surfactant concentration. The combination of different techniques (rheology, laser diffraction and multiple light scattering) was demonstrated to be a powerful tool to assist in the prediction of the emulsions destabilization process. Not only did the addition of rosin gum highly increase the stability of these emulsions by inhibiting the Ostwald ripening, but it also reduced the emulsions droplet size. Thus, we found that stable sub-micron D-limonene-in-water emulsions have been obtained in the range 3-6 wt% Pluronic PE-9400 by means of a single-step rotor/stator homogenizing process. PMID:25454661

  20. Comparative studies of binding potential of Prunus armeniaca and Prunus domestica gums in tablets formulations.

    PubMed

    Rahim, Haroon; Khan, Mir Azam; Sadiq, Abdul; Khan, Shahzeb; Chishti, Kamran Ahmad; Rahman, Inayat U

    2015-05-01

    The current study was undertaken to compare the binding potential of Prunus armeniaca L. and Prunus domestica L. gums in tablets' formulations. Tablet batches (F-1 to F-9) were prepared Diclofenac sodium as model drug using 5%, 7.5% and 10% of each Prunus armeniaca L., Prunus domestica L. gums as binder. PVP K30 was used as a standard binder. Magnesium stearate was used as lubricant. Flow properties of granules (like bulk density, tapped density, Carr's index, Hausner's ratio, angle of repose) as well as the physical parameters of compressed tablets including hardness, friability, thickness and disintegration time were determined. Flow parameters of granules of all the batches were found good. Physical parameters (drug content, weight variation, thickness, hardness, friability, disintegration time) of formulated tablets were found within limit when tested. The dissolution studies showed that tablets formulations containing each Prunus domestica showed better binding capacity compared to Prunus armeniaca gum. The binding potential increased as the concentration of gums increased. The FTIR spectroscopic investigation showed that the formulations containing plant gum are compatible with the drug and other excipients used. PMID:26004724

  1. Hormonal regulation of gummosis and composition of gums from bulbs of hyacinth (Hyacinthus orientalis).

    PubMed

    Miyamoto, Kensuke; Kotake, Toshihisa; Boncela, Anna Jarecka; Saniewski, Marian; Ueda, Junichi

    2015-02-01

    Hyacinth (Hyacinthus orientalis) bulbs infected by Fusarium oxysporum showed the symptoms of gummosis. The purpose of this study was to clarify the hormonal regulation of gummosis and composition of gums from hyacinth bulbs. The application of ethephon (2-chloroethylphosphonic acid), an ethylene-releasing compound, at 2% (w/w, in lanolin) induced gummosis in hyacinth bulbs. Methyl jasmonate (JA-Me) at 1.5% (w/w, in lanolin) induced gummosis as well. Simultaneous application of JA-Me and ethephon further enhanced gummosis. Molecular mass distribution of hyacinth gums analyzed by gel permeation chromatography indicated that the gums were mainly homogenous polysaccharides with an average molecular weight of ca. 30kDa. Analysis of the sugar composition of the gums after hydrolysis revealed that the majority were arabinose (ca. 35%) and galactose (ca. 40%) together with small amounts of fucose, rhamnose and uronic acids (ca. 5%, respectively), suggesting that the gums are pectic arabinogalactans. These results indicate that jasmonates (JAs) interact with ethylene to stimulate sugar metabolism, producing pectic arabinogalactans, and vice versa, leading to gummosis. These findings, together with those from our previous studies in tulips (Tulipa gesneriana) and grape hyacinth (Muscari armeniacum), revealed that sugar metabolism and hormonal regulation relating to gummosis are different among species of bulbous plants. PMID:25462960

  2. In Vitro and In Vivo Activities of Chios Mastic Gum Extracts and Constituents against Helicobacter pylori?

    PubMed Central

    Paraschos, Sotirios; Magiatis, Prokopios; Mitakou, Sofia; Petraki, Kalliopi; Kalliaropoulos, Antonios; Maragkoudakis, Petros; Mentis, Andreas; Sgouras, Dionyssios; Skaltsounis, Alexios-Leandros

    2007-01-01

    The extracts and pure major constituents of Chios mastic gum (resin of Pistacia lentiscus var. chia) were tested for their activities against Helicobacter pylori. A total mastic extract without polymer (TMEWP) was prepared after removal of the contained insoluble polymer in order to ameliorate solubility and enhance in vivo activity. Administration of TMEWP to H. pylori SS1-infected mice over the period of 3 months with an average dose of 0.75 mg/day led to an approximately 30-fold reduction in the H. pylori colonization (1.5 log CFU/g of tissue). However, no attenuation in the H. pylori-associated chronic inflammatory infiltration and the activity of chronic gastritis was observed. To further characterize potential active mastic constituents, the TMEWP was separated into an acidic and a neutral fraction. Both were extensively characterized by nuclear magnetic resonance and mass spectroscopy to elucidate the structure of the components contained within each fraction. After chromatographic separation, the acid fraction gave the major triterpenic acids, while the neutral fraction gave several triterpenic alcohols and aldehydes. Mastic extracts and isolated pure triterpenic acids were tested for in vitro activity against a panel of 11 H. pylori clinical strains. The acid fraction was found to be the most active extract (minimum bactericidal concentration [MBC], 0.139 mg/ml), and the most active pure compound was isomasticadienolic acid (MBC, 0.202 mg/ml [0.443 mM]). Our results show that administration of TMEWP may be effective in reducing H. pylori colonization and that the major triterpenic acids in the acid extract may be responsible for such an activity. PMID:17116667

  3. Nicotine Gum and Self-Help Behavioral Treatment for Smoking Relapse Prevention: Results from a Trial Using Population-Based Recruitment.

    ERIC Educational Resources Information Center

    Fortmann, Stephen P.; Killen, Joel D.

    1995-01-01

    Smokers were randomized using a factorial design to compare nicotine gum use to no gum use, and self-help materials to no materials. Compared with the no-gum group, relapse occurred at a significantly lower rate in the gum group for the entire 12 months of follow-up. There was no significant main effect for the self-help materials and no…

  4. Effects of sugarless chewing gum as a stimulant on progesterone, cortisol, and testosterone concentrations assessed in saliva

    E-print Network

    Schultheiss, Oliver C.

    increase, relative to no-gum controls and attenuated salivary testosterone and cortisol concentra- tionsEffects of sugarless chewing gum as a stimulant on progesterone, cortisol, and testosterone November 2012 Accepted 28 November 2012 Available online 6 December 2012 Keywords: Salivary hormone assay

  5. Helping people to stop smoking: randomised comparison of groups being treated with acupuncture and nicotine gum with control group

    E-print Network

    Paris-Sud XI, Université de

    Helping people to stop smoking: randomised comparison of groups being treated with acupuncture people to stop smoking are acupuncture1,2 and nicotine gum.3,4 We report the results of a randomised and people with gastric ulcers or a history of heart disease. Treatment (acupuncture, nicotine gum

  6. Microwave-promoted hydrolysis of plant seed gums on alumina support.

    PubMed

    Singh, Vandana; Tiwari, Ashutosh; Kumari, Premlata; Tiwari, Stuti

    2006-09-25

    Using a catalytic amount of potassium persulfate (1.48 x 10(-4)M), eight different seed gums were fully hydrolyzed on alumina support under microwave irradiation. The hydrolysis time varied between 1.33 and 2.33 min depending upon the seed gum structure. The used solid support could be easily separated from the hydrolyzates and recycled. However, under microwave field in an aqueous medium, the same amount of persulfate was unable to hydrolyze the seed gums. Solid-supported microwave hydrolysis has been compared with the microwave-enhanced aqueous hydrolysis (using K2S2O8 or 0.1N H2SO4) and also with the conventional hydrolysis procedures. PMID:16806127

  7. Xanthan Gum-a lyotropic, liquid crystalline polymer and its properties as a suspending agent

    SciTech Connect

    Salamone, J.C.; Clough, S.B.; Jamison, D.E.; Reid, K.I.G.; Salamone, A.B.

    1982-08-01

    Studies a variety of xanthan solutions of various polymer concentrations in the presence and absence of various salts under a polarized light microscope (100X) in order to test xanthan gum for liquid crystalline order. Xanthan gum, a polysaccharide used in drilling fluids and in tertiary recovery, has relatively stable viscosity properties as a function of salt concentration, pH, temperature, and shear degradation. With solutions from 2 to 10% (wt/vol) xanthan gum in distilled water at room temperature, birefringent, ordered domains were observed at 10% concentration, with a decrease in birefringence as the polymer concentration decreased. When the xanthan solution is sheared between a glass slide and a cover slip, the optic axis (chain direction) aligns using the shear direction (as determined by the colors displayed using a first-order red plate). Examines liquid crystalline behavior of other naturally occurring polymers.

  8. Discovery of X-ray emission associated with the Gum Nebula

    NASA Technical Reports Server (NTRS)

    Leahy, D. A.; Nousek, J.; Garmire, G.

    1992-01-01

    The Gum Nebula was observed by the A-2 LED proportional counters on the HEAO-1 satellite as part of the all-sky survey. The first detection of X-ray emission associated with the Gum Nebula is reported. Soft X-ray spectra were constructed from the A-2 LED PHA data. Single temperature Raymond-Smith models were fitted to the observed spectra to yield temperature, column density and emission measure. The temperature is 6 x 10 exp 5 K, the column density 4 x 10 exp 20/sq cm, and the emission measure 5 cm exp-6 pc. The X-ray and optical properties of the Gum Nebula are consistent with a supernova remnant in the shell stage of evolution, which was the product of an energetic (3 x 10 exp 51 ergs) supernova explosion which occurred about 2 x 10 exp 6 yr ago.

  9. Viscosity of locust bean, guar and xanthan gum solutions in the Newtonian domain: a critical examination of the log ( ? sp ) o -log c[ ?] o master curves

    Microsoft Academic Search

    Bernard Launay; Gérard Cuvelier; Salomon Martinez-Reyes

    1997-01-01

    The viscosity in the low shear rate Newtonian domain of three biopolymers, locust bean gum, guar gum and xanthan gum was studied as a function of temperature and of polymer concentration in various aqueous solvents. The intrinsic viscosities [?]o of both galactomannans are not modified in the presence of 10 or 40% sucrose. In this case, a master curve relating

  10. Cardiovascular responses in humans to experimental chewing of gums of different consistencies.

    PubMed

    Farella, M; Bakke, M; Michelotti, A; Marotta, G; Martina, R

    1999-10-01

    Although the cardiovascular effects of exercise have been extensively investigated in man, little attention has been paid to such responses to jaw muscle activity. The aim here was to investigate the general cardiovascular effects of chewing activity in a single-blind, cross-over design. Ten healthy individuals performed one of the following chewing tasks in four separate sessions: chewing a very hard gum, chewing a moderately hard gum, chewing a soft gum, and "empty chewing" without a bolus. Unilateral chewing of gum or empty chewing was performed for 20 min on the participant's most convenient chewing side at a constant rate of 80 cycles/min. In each session, heart rate and arterial blood pressure were recorded together with electromyographic activity in the masseter and anterior temporalis muscles on the chewing side. Ratings of perceived masticatory fatigue were recorded with visual analogue scales. The heart rate and blood pressure were significantly increased (ANOVA; p < or= 0.01) during the chewing tasks and the increases were, in parallel with the muscle activity, more pronounced the harder the gum. With the very hard gum, heart rate increased by up to 11 beats/min, the systolic blood pressure was 14 mmHg (1.9kPa) higher, and the diastolic blood pressure was 11 mmHg (1.5kPa) higher. The perceived fatigue was proportional to the level of muscle activity. After 10 min of recovery from exercise, heart rate and arterial blood pressures were slightly but still significantly elevated. The results demonstrate that chewing is associated with general circulatory effects proportional to the bolus resistance. PMID:10530916

  11. Natural gums as sustained release carriers: development of gastroretentive drug delivery system of ziprasidone HCl

    PubMed Central

    2012-01-01

    Background Objective of this study is to show the potential use of natural gums in the development of drug delivery systems. Therefore in this work gastro retentive tablet formulations of ziprasidone HCl were developed using simplex lattice design considering concentration of okra gum, locust bean gum and HPMC K4M as independent variables. A response surface plot and multiple regression equations were used to evaluate the effect of independent variables on hardness, flag time, floating time and drug release for 1 h, 2 h, and 8 h and for 24 h. A checkpoint batch was also prepared by considering the constraints and desirability of optimized formulation to improve its in vitro performance. Significance of result was analyzed using ANOVA and p < 0.05 was considered statistically significant. Results Formulation chiefly contains locust bean gum found to be favorable for hardness and floatability but combined effect of three variables was responsible for the sustained release of drug. The in vitro drug release data of check point batch (F8) was found to be sustained well compared to the most satisfactory formulation (F7) of 7 runs. The ‘n’ value was found to be between 0.5 and 1 suggesting that release of drug follows anomalous (non-fickian) diffusion mechanism indicating both diffusion and erosion mechanism from these natural gums. Predicted results were almost similar to the observed experimental values indicating the accuracy of the design. In vivo floatability test indicated non adherence to the gastric mucosa and tablets remain buoyant for more than 24 h. Conclusions Study showed these eco-friendly natural gums can be considered as promising SR polymers. PMID:23352292

  12. The deformation of gum metal under nanoindentation and sub-micron pillar compression

    NASA Astrophysics Data System (ADS)

    Withey, Elizabeth Ann

    Reaching ideal strength has proven to be difficult in most materials. Dislocation slip, phase transformations, twinning, and fracture all tend to occur at stresses well below the ideal strength of a material. Only on very small scales has it been possible to approach ideal strength. Thus, it was of great interest when a set of beta-Ti alloys, Gum Metal, were found to have a bulk yield strength close to half of its ideal strength. However, some recent studies have questioned the reliability of this claim. Several studies have suggested Gum Metal deforms by dislocation slip. Others have suggested the possibility of transformation-induced plasticity. The present study was undertaken in order to help clarify if and how Gum Metal can reach ideal strength. Two different experiments, ex situ nanoindentation and quantitative in situ nanopillar compression in a transmission electron microscope to correlate real-time deformation behavior, were performed on a single composition of Gum Metal, Ti-23Nb-0.7Ta-2Zr-1.20 at. %, obtained from Toyota Central R&D Laboratories. Nanoindented specimens were thinned from the bottom surface until the pits of multiple indentations became electron-transparent allowing for qualitative analysis of the deformation microstructure in both fully cold-worked and solution-treated specimens. Real-time load-displacement behavior from the nanopillar compression tests was correlated with real-time video recorded during each compression to determine both the compressive strength of each pillar and the timing and strengths of different deformation behaviors observed. Combining the results from both experiments provided several important conclusions. First, Gum Metal approaches and can attain ideal strength in nanopillars regardless of processing condition. While dislocations exist in Gum Metal, they can be tightly pinned by obstacles with spacing less than ˜20 nm, which should inhibit their motion at strengths below the ideal shear strength. The plastic deformation of Gum Metal is not controlled by giant faults or by stress-induced phase transformations. Both of these phenomena, while active, are not the source of plasticity in Gum Metal.

  13. Theory of the nonplanar splitting of screw dislocations in Gum Metal

    NASA Astrophysics Data System (ADS)

    Bobylev, S. V.; Ishizaki, T.; Kuramoto, S.; Ovid'Ko, I. A.

    2008-03-01

    A theoretical model is suggested that describes nonplanar splitting of perfect dislocations into partials in a newly discovered group of alloys called Gum Metal. Within the model, the partials have line cores located at a nanoscale circle and are connected by (generalized) stacking faults. Due to the complicated nonplanar structure of the split dislocation configuration and associated stacking faults, the split dislocation has a low mobility. Results of the model take into account experimental data on suppression of dislocation slip in Gum Metal reported in the literature.

  14. Anti-inflammatory activity of Chios mastic gum is associated with inhibition of TNF-alpha induced oxidative stress

    PubMed Central

    2011-01-01

    Background Gum of Chios mastic (Pistacia lentiscus var. chia) is a natural antimicrobial agent that has found extensive use in pharmaceutical products and as a nutritional supplement. The molecular mechanisms of its anti-inflammatory activity, however, are not clear. In this work, the potential role of antioxidant activity of Chios mastic gum has been evaluated. Methods Scavenging of superoxide radical was investigated by electron spin resonance and spin trapping technique using EMPO spin trap in xanthine oxidase system. Superoxide production in endothelial and smooth muscle cells stimulated with TNF-? or angiotensin II and treated with vehicle (DMSO) or mastic gum (0.1-10 ?g/ml) was measured by DHE and HPLC. Cellular H2O2 was measured by Amplex Red. Inhibition of protein kinase C (PKC) with mastic gum was determined by the decrease of purified PKC activity, by inhibition of PKC activity in cellular homogenate and by attenuation of superoxide production in cells treated with PKC activator phorbol 12-myristate 13-acetate (PMA). Results Spin trapping study did not show significant scavenging of superoxide by mastic gum itself. However, mastic gum inhibited cellular production of superoxide and H2O2 in dose dependent manner in TNF-? treated rat aortic smooth muscle cells but did not affect unstimulated cells. TNF-? significantly increased the cellular superoxide production by NADPH oxidase, while mastic gum completely abolished this stimulation. Mastic gum inhibited the activity of purified PKC, decreased PKC activity in cell homogenate, and attenuated superoxide production in cells stimulated with PKC activator PMA and PKC-dependent angiotensin II in endothelial cells. Conclusion We suggest that mastic gum inhibits PKC which attenuates production of superoxide and H2O2 by NADPH oxidases. This antioxidant property may have direct implication to the anti-inflammatory activity of the Chios mastic gum. PMID:21645369

  15. The Xanthomonas campestris gumDGene Required for Synthesis of Xanthan Gum Is Involved in Normal Pigmentation and Virulence in Causing Black Rot

    Microsoft Academic Search

    Fang-Li Chou; Huei-Chi Chou; Yen-Shin Lin; Bih-Ying Yang; Nien-Tsung Lin; Shu-Fen Weng; Yi-Hsiung Tseng

    1997-01-01

    A cloned 4.1-kbEcoRI fragment fromXanthomonas campestrispv.campestriswas previously shown to complement the non-mucoid mutant P22 and increase xanthan gum production after being transformed into the wild-type strain Xc17. The gene responsible for these effects was identified, sequenced, and shown to be thegumDgene which has previously been proposed to encode glucose transferase activity, an enzyme required for adding the first glucose residue

  16. Partially hydrolyzed guar gum in pediatric functional abdominal pain

    PubMed Central

    Romano, Claudio; Comito, Donatella; Famiani, Annalisa; Calamarà, Sabrina; Loddo, Italia

    2013-01-01

    AIM: To assess the effects of partially hydrolyzed guar gum (PHGG) diet supplement in pediatric chronic abdominal pain (CAP) and irritable bowel syndrome (IBS). METHODS: A randomized, double-blind pilot study was performed in sixty children (8-16 years) with functional bowel disorders, such as CAP or IBS, diagnosed according to Rome III criteria. All patients underwent ultrasound, blood and stool examinations to rule out any organic disease. Patients were allocated to receive PHGG at dosage of 5 g/d (n = 30) or placebo (fruit-juice n = 30) for 4 wk. The evaluation of the efficacy of fiber supplement included IBS symptom severity score (Birmingham IBS Questionnaire), severity of abdominal pain (Wong-Baker Face Pain Rating Score) and bowel habit (Bristol Stool Scale). Symptom scores were completed at 2, 4, and 8 wk. The change from baseline in the symptom severity scale at the end of treatment and at 4 wk follow-up after treatment was the primary endpoint. The secondary endpoint was to evaluate compliance to supplementation with the PHGG in the pediatric population. Differences within groups during the treatment period and follow-up were evaluated by the Wilcoxon signed-rank test. RESULTS: The results of the study were assessed considering some variables, such as frequency and intensity of symptoms with modifications of the bowel habit. Both groups were balanced for baseline characteristics and all patients completed the study. Group A (PHGG group) presented a higher level of efficacy compared to group B (control group), (43% vs 5%, P = 0.025) in reducing clinical symptoms with modification of Birmingham IBS score (median 0 ± 1 vs 4 ± 1, P = 0.025), in intensity of CAP assessed with the Wong-Baker Face Pain Rating Score and in normalization of bowel habit evaluated with the Bristol Stool Scale (40% vs 13.3%, P = 0.025). In IBS subgroups, statistical analysis shown a tendency toward normalization of bowel movements, but there was no difference in the prevalence of improvement in two bowel habit subsets. PHGG was therefore better tolerated without any adverse effects. CONCLUSION: Although the cause of pediatric functional gastrointestinal disorders is not known, the results show that complementary therapy with PHGG may have beneficial effects on symptom control. PMID:23345946

  17. Chemical composition and rheology of low-fat Iranian white cheese incorporated with guar gum and gum arabic as fat replacers.

    PubMed

    Lashkari, Hannan; Khosrowshahi Asl, Asghar; Madadlou, Ashkan; Alizadeh, Mohammad

    2014-10-01

    The effects of incorporating guar gum (GG) and gum arabic (GA) in cheese-making milk with various fat contents (0.4, 0.9, and 1.4 %) on chemical and rheological properties of Iranian white cheese were evaluated by response surface method (RSM). As GG concentration increased, dry matter content of cheese samples decreased due to the high water binding capacity of this gum. A similar trend was also observed for GA at concentrations less than 150 ppm. The higher the GG concentration, the higher was the free fatty acid content of cheese samples. GA at concentrations more than 150 ppm, increased the storage modulus (G'), causing an undesirable hard texture for the product. The G' and stress at fracture (?f) of samples decreased by the increasing concentration of GG incorporated into the cheese-making milk. Response surface minimization of rheological indices for Iranian white cheese showed that combination of two hydrocolloids (GG in the concentration range 75-170 ppm and GA at concentrations <75 ppm) would provide the softest texture. PMID:25328199

  18. Magnetism

    NSDL National Science Digital Library

    David Stern

    This overview of magnetism provides a brief history prior to 1600 and continues with the work of William Gilbert, Hans Christian Oersted, and Andre-Marie Ampere in describing and exploring the magnetosphere and learning the role that electric current plays in producing magnetism. Magnetic field lines are then discussed, citing the work of Michael Faraday. The work of James Clerk Maxwell and Heinrich Hertz is mentioned in a discussion of the relationship of light waves and radio waves as part of the electromagnetic spectrum.

  19. "JCE" Classroom Activity #105. A Sticky Situation: Chewing Gum and Solubility

    ERIC Educational Resources Information Center

    Montes-Gonzalez, Ingrid; Cintron-Maldonado, Jose A.; Perez-Medina, Ilia E.; Montes-Berrios, Veronica; Roman-Lopez, Saurie N.

    2010-01-01

    In this Activity, students perform several solubility tests using common food items such as chocolate, chewing gum, water, sugar, and oil. From their observations during the Activity, students will initially classify the substances tested as soluble or insoluble. They will then use their understanding of the chemistry of solubility to classify the…

  20. Release of peppermint flavour compounds from chewing gum: effect of oral functions

    Microsoft Academic Search

    Anne-Mette Haahr; Allan Bardow; Carsten E. Thomsen; Siri B. Jensen; Birgitte Nauntofte; Merete Bakke; Jens Adler-Nissen; Wender L. P. Bredie

    2004-01-01

    During chewing, the oral cavity functions like a bellow, forcing volatile flavour compounds into the exhaling air to the nasal compartment. Accordingly, we hypothesised that flavour release from chewing gum is predominantly governed by chewing frequency (CF), although other oral functions, like masseter muscle activity (MMA), chewing force (CFO), and saliva flow rate (SFR), may also play a role. In

  1. In Vitro and In Vivo Activities of Chios Mastic Gum Extracts and Constituents against Helicobacter pylori

    Microsoft Academic Search

    Sotirios Paraschos; Prokopios Magiatis; Sofia Mitakou; Kalliopi Petraki; Antonios Kalliaropoulos; Petros Maragkoudakis; Andreas Mentis; Dionyssios Sgouras; Alexios-Leandros Skaltsounis

    2007-01-01

    The extracts and pure major constituents of Chios mastic gum (resin of Pistacia lentiscus var. chia) were tested for their activities against Helicobacter pylori. A total mastic extract without polymer (TMEWP) was prepared after removal of the contained insoluble polymer in order to ameliorate solubility and enhance in vivo activity. Administration of TMEWP to H. pylori SS1-infected mice over the

  2. Effects of chewing gum on driving performance as evaluated by the STISIM driving simulator

    PubMed Central

    Yoo, Ingyu; Kim, Eun-Joo; Lee, Joo-Hyun

    2015-01-01

    [Purpose] The purpose of this study was to determine the effects of chewing gum on driving performance in a driving simulator. [Subjects] In total, 26 young licensed drivers participated. [Methods] The driving scenario was typical of an urban environment: a single-carriageway, two-way road consisting of a mix of curved and straight sections, with considerable levels of traffic, pedestrians, and parked cars. Mean distance driven above the speed limit, lane position, mean distance driven across the center line, and mean distance driven off the road were used as estimates of brake, accelerator, and steering control. The results were compared with those of a non-chewing gum control condition. [Results] The driving performance while chewing gum was significantly better: the mean distance driven above the speed limit was 26.61% shorter, and the mean distance driven off the road was 31.99% shorter. Lane position and mean distance driven across the center line did not differ significantly between the two conditions. [Conclusion] Chewing gum appears to enhance driving performance during a sustained attention driving task. PMID:26180329

  3. Compared effects of the viscosity of three guar gums on plasma blood glu-

    E-print Network

    Paris-Sud XI, Université de

    ) which simulated human food. Six per- cent guar gum of low (G6), medium (G3) or high (Gl) viscosity insulin postprandial peaks were significantly lower than the FF peak (P G6 reduced by Gi compared to FF and G6 diets but not with the G3 diet. These results were well correlated

  4. Association between masticatory performance using a colour-changeable chewing gum and jaw movement.

    PubMed

    Komagamine, Y; Kanazawa, M; Minakuchi, S; Uchida, T; Sasaki, Y

    2011-08-01

    The purpose of this study was to investigate the relationship between masticatory performance as determined using a colour-changeable chewing gum and mandibular movements. Subjects comprised 45 fully dentate adults (23 men, 22 women; mean age, 28·1 years). The gum was chewed for a specified number of chewing strokes (20, 40, 60, 80, 120 or 160 strokes) without any instructions as to chewing side. A colourimeter was used to measure L*, a* and b* values (CIE-L*a*b* colour system) for the chewed gum, then the difference between two colours in the CIE-L*a*b* colour space (?E) for each number of chewing strokes was calculated according to a formula. Index of masticatory performance (?E60) for each subject was obtained using ?E for 20, 40, 60, 80, 120 and 160 strokes. Mandibular movements were recorded using an opto-electric system with six degrees of freedom. Twelve parameters of mandibular movements relating to amplitude, duration, velocity and angle were computed for each cycle, and mean values for 10 cycles (from cycle 11 to 20) were calculated separately. Stepwise multiple regression analysis identified maximum closing velocity and closing angle as predictors accounting for 18% of the variation in ?E60. These results suggest that lower angles of approach to intercuspation and faster speed during closing duration are associated with colour changes in the colour-changeable chewing gum. PMID:21314707

  5. Detection of subgingival calculus through oral gum in vitro using two-photon fluorescence microscopy

    Microsoft Academic Search

    Oi-Hong Tung; Shyh-Yuan Lee; Yu-Lin Lai; How-Foo Chen

    2008-01-01

    Periodontal disease is one of the main chronic infectious diseases of oral cavity and the principal cause of tooth loss in humans. The main cause of periodontal disease is the bacteria in calculus or plaque to cause the gum inflamed. Therefore detection and removal of subgingival calculus remains important to all periodontal therapy. However, subgingival calculus within the periodontal pocket

  6. Effect of Regular Gum Chewing on Levels of Anxiety, Mood, and Fatigue in Healthy Young Adults

    PubMed Central

    Sasaki-Otomaru, Akiyo; Sakuma, Yumiko; Mochizuki, Yoshiko; Ishida, Sadayo; Kanoya, Yuka; Sato, Chifumi

    2011-01-01

    Introduction: The effect of regular gum chewing on psychological status is unknown. The purpose of this study was to examine the effect of gum chewing for fourteen days on psychological status and physical and mental fatigue in healthy young adults. Methods: We assigned 50 volunteers randomly to an intervention group (n = 26) and a control group (n = 24). Participants in the intervention group were requested to chew the gum twice per a day for fourteen days. The volunteers were required to complete a questionnaire related to lifestyle for baseline assessment. The State-Trait Anxiety Inventory (STAI), the Profile of Mood State (POMS), the World Health Organization Quality of Life 26, and assessment of physical and mental fatigue by visual analog scale were used at baseline, 2 weeks (after intervention), and 4 weeks (follow-up). Results: At 2 weeks, the score of state anxiety was significantly lower in the intervention group than the control group. The intervention participants’ scores of depression-dejection, fatigue and confusion in POMS were better than the control group scores. Mental fatigue were also relieved after the intervention. At 4 weeks, there were no significant differences between both groups. Conclusion: Fourteen days’ gum chewing may improve the levels of anxiety, mood and fatigue. PMID:21866229

  7. Fractionation, characterization and study of emulsifying properties of corn fiber gum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn fiber gum has been fractionated by hydrophobic interaction chromatography on Amberlite XAD-1180 resin using ionic, acidic, basic and hydrophobic solvents of different polarity. Characterization, including determination of total carbohydrate, acidic sugar and protein content has been done for e...

  8. Effectiveness of a GUM-Compliant Course for Teaching Measurement in the Introductory Physics Laboratory

    ERIC Educational Resources Information Center

    Pillay, Seshini; Buffler, Andy; Lubben, Fred; Allie, Saalih

    2008-01-01

    An evaluation of a course aimed at developing university students' understanding of the nature of scientific measurement and uncertainty is described. The course materials follow the framework for metrology as recommended in the "Guide to the Expression of Uncertainty in Measurement" (GUM). The evaluation of the course is based on responses to…

  9. Effects of corn fiber gum (CFG) on the pasting and thermal behaviors of maize starch

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn fiber gum (CFG) is a novel arabinoxylan hydrocolloid. Recent research showed its considerable potential in food processing. In this study, the interactions of maize starch and CFG were studied. Maize starch/CFG blend gels were prepared from maize starch suspension mixed with 0.1%, 0.25%, 0.5%, ...

  10. Analysing options for the Red Gum Forests along the Murray River

    Microsoft Academic Search

    Jeffrey W. Bennett; Robert G. Dumsday; Robert Gillespie

    2008-01-01

    The Victorian Environmental Assessment Council is conducting an investigation into the management of the public land River Red Gum Forests of the Murray River Valley in Victoria. In this paper the authors apply the results of an earlier Choice Modelling exercise commissioned by VEAC to estimate the non-use values of the forests. A Benefit Cost Analysis of VEAC's draft recommendations

  11. Estudio de la extinción interestelar en dirección a la Nebulosa Gum

    NASA Astrophysics Data System (ADS)

    Giorgi, E. E.; Solivella, G. R.; Vázquez, R. A.; Baume, G. L.

    In this article we report results from a spectroscopic and photometric study carried out with 61 stars located in the regions of 6 open clusters at the south-east and north-west zones of the Gum Nebula with the aim of analizing the path of the reddening in this section of the Galaxy. FULL TEXT IN SPANISH

  12. Reduction of the viscosity of solutions viscosified with xanthan gum polymers

    SciTech Connect

    Bridges, K.L.; Kalinski, K.L.

    1991-10-08

    This patent describes a process for reducing the viscosity of a drilling fluid containing Xanthan gum polymer solution. It comprises: contacting the drilling fluid with hydrogen peroxide and adjusting the pH of the solution to a level of at least about between 8 and 10.

  13. Dielectric and Thermal Properties of Rice Cake Formulations Containing Different Gums Types

    Microsoft Academic Search

    Elif Turabi; Marc Regier; Gulum Sumnu; Serpil Sahin; Matthias Rother

    2010-01-01

    In this study, dielectric properties of rice cake formulations containing different gum types (xanthan, guar, locust bean, HPMC, and kappa-carrageenan) were determined at temperatures between 25 and 90°C at 2450 MHz. Moreover, thermal properties of these formulations were determined by using differential scanning calorimeter (DSC). Dielectric properties of cake batters were found to be dependent on cake formulation. Xanthan and

  14. Two-colour chewing gum mixing ability: digitalisation and spatial heterogeneity analysis.

    PubMed

    Weijenberg, R A F; Scherder, E J A; Visscher, C M; Gorissen, T; Yoshida, E; Lobbezoo, F

    2013-10-01

    Many techniques are available to assess masticatory performance, but not all are appropriate for every population. A proxy suitable for elderly persons suffering from dementia was lacking, and a two-colour chewing gum mixing ability test was investigated for this purpose. A fully automated digital analysis algorithm was applied to a mixing ability test using two-coloured gum samples in a stepwise increased number of chewing cycles protocol (Experiment 1: n = 14; seven men, 19-63 years), a test-retest assessment (Experiment 2: n = 10; four men, 20-49 years) and compared to an established wax cubes mixing ability test (Experiment 3: n = 13; 0 men, 21-31 years). Data were analysed with repeated measures anova (Experiment 1), the calculation of the intraclass correlation coefficient (ICC; Experiment 2) and Spearman's rho correlation coefficient (Experiment 3). The method was sensitive to increasing numbers of chewing cycles (F5,65 = 57·270, P = 0·000) and reliable in the test-retest (ICC value of 0·714, P = 0·004). There was no significant correlation between the two-coloured gum test and the wax cubes test. The two-coloured gum mixing ability test was able to adequately assess masticatory function and is recommended for use in a population of elderly persons with dementia. PMID:23927753

  15. Gum arabic as a potential corrosion inhibitor for aluminium in alkaline medium and its adsorption characteristics

    Microsoft Academic Search

    S. A. Umoren; I. B. Obot; E. E. Ebenso; P. C. Okafor; O. Ogbobe; E. E. Oguzie

    2006-01-01

    Purpose – To investigate the inhibitive effect of gum arabic (GA) for the corrosion of aluminium in alkaline (NaOH) medium and determine its adsorption characteristics. The present work is another trial to find a cheap and environmentally safe inhibitor for aluminium corrosion. Design\\/methodology\\/approach – The inhibition efficiency (%I) has been evaluated using the hydrogen evolution (via the gasometric assembly) and

  16. Production of corn fiber gum under conditions that retain its functional components

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn fiber gum (CFG) is a hemicellulose (arabinoxylan)-enriched fraction obtained by the extraction of corn bran/fiber using a mild alkaline hydrogen peroxide process. The unique polysaccharide, CFG, with its low solution viscosity has been proposed as a stabilizer for oil-in-water emulsions. We ha...

  17. Corn fiber gum and milk protein conjugates with improved emulsion stability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn fiber gum (CFG), an alkaline hydrogen peroxide extract of the corn kernel milling by-product “corn fiber” was covalently conjugated with Beta-lactoglobulin (Beta-LG) and whey protein isolate (WPI). Covalent coupling of CFG to protein was achieved by dry heating reaction (Maillard-type) of CFG ...

  18. Colon Targeted Guar Gum Compression Coated Tablets of Flurbiprofen: Formulation, Development, and Pharmacokinetics

    PubMed Central

    Bontha, Vijaya Kumar

    2013-01-01

    The rationale of the present study is to formulate flurbiprofen colon targeted compression coated tablets using guar gum to improve the therapeutic efficacy by increasing drug levels in colon, and also to reduce the side effects in upper gastrointestinal tract. Direct compression method was used to prepare flurbiprofen core tablets, and they were compression coated with guar gum. Then the tablets were optimized with the support of in vitro dissolution studies, and further it was proved by pharmacokinetic studies. The optimized formulation (F4) showed almost complete drug release in the colon (99.86%) within 24?h without drug loss in the initial lag period of 5?h (only 6.84% drug release was observed during this period). The pharmacokinetic estimations proved the capability of guar gum compression coated tablets to achieve colon targeting. The Cmax of colon targeted tablets was 11956.15?ng/mL at Tmax of 10?h whereas it was 15677.52?ng/mL at 3?h in case of immediate release tablets. The area under the curve for the immediate release and compression coated tablets was 40385.78 and 78214.50?ng-h/mL and the mean resident time was 3.49 and 10.78?h, respectively. In conclusion, formulation of guar gum compression coated tablets was appropriate for colon targeting of flurbiprofen. PMID:24260738

  19. A review of recent developments on the regulatory, structural and functional aspects of gum arabic

    Microsoft Academic Search

    A. M. Islam; G. O. Phillips; A. Sljivo; M. J. Snowden; P. A. Williams

    1997-01-01

    There have been substantial developments recently concerning the regulatory aspects of gum arable and the elucidation of its structure and functional characteristics. The aim of this paper is to present the position with regard to its current legal definition, to summarize what is now known about the structure of this complex polysaccharide and to illustrate how the structural features relate

  20. Biobased adhesives, gums, emulsions, and binders: current trends and future prospects

    Microsoft Academic Search

    Syed H. Imam; Cristina Bilbao-Sainz; Bor-Sen Chiou; Gregory M. Glenn; William J. Orts

    2012-01-01

    Biopolymers derived from renewable resources are an emerging class of advanced materials that offer many useful properties for a wide range of food and nonfood applications. Current state of the art in research and development of renewable polymers as adhesives, gums, binders, and emulsions is the subject of this review. Much of the focus will be on major biopolymers such

  1. The use of Hibiscus esculentus (Okra) gum in sustaining the release of propranolol hydrochloride in a solid oral dosage form.

    PubMed

    Zaharuddin, Nurul Dhania; Noordin, Mohamed Ibrahim; Kadivar, Ali

    2014-01-01

    The effectiveness of Okra gum in sustaining the release of propranolol hydrochloride in a tablet was studied. Okra gum was extracted from the pods of Hibiscus esculentus using acetone as a drying agent. Dried Okra gum was made into powder form and its physical and chemical characteristics such as solubility, pH, moisture content, viscosity, morphology study using SEM, infrared study using FTIR, crystallinity study using XRD, and thermal study using DSC and TGA were carried out. The powder was used in the preparation of tablet using granulation and compression methods. Propranolol hydrochloride was used as a model drug and the activity of Okra gum as a binder was compared by preparing tablets using a synthetic and a semisynthetic binder which are hydroxylmethylpropyl cellulose (HPMC) and sodium alginate, respectively. Evaluation of drug release kinetics that was attained from dissolution studies showed that Okra gum retarded the release up to 24 hours and exhibited the longest release as compared to HPMC and sodium alginate. The tensile and crushing strength of tablets was also evaluated by conducting hardness and friability tests. Okra gum was observed to produce tablets with the highest hardness value and lowest friability. Hence, Okra gum was testified as an effective adjuvant to produce favourable sustained release tablets with strong tensile and crushing strength. PMID:24678512

  2. Chewing gum has large effects on salivary testosterone, estradiol, and secretory immunoglobulin A assays in women and men.

    PubMed

    van Anders, Sari M

    2010-02-01

    Salivary assays are increasingly prevalent in behavioral research, and chewing gum is a widely used sialogogue. Methodological investigations into sialogogues have provided mixed results, and few of these have incorporated multiple analytes, gums, and genders. To test effects of gum on salivary testosterone (T), estradiol (E), and immunoglobulin A (IgA) assays, participants (86 women; 91 men) provided two saliva samples, the first of which was unstimulated. Participants were randomly assigned to one of the following seven conditions for the second sample, which was provided after the first: No Gum or one of six sugar-free gums with one of two flavors and three brands. This design avoided the confounding of time and condition by comparing endogenously vs. exogenously induced changes in analytes. Chewing gum significantly decreased production time for the second saliva samples by 3-6 min, and had very large effects on assay results, leading to lower IgA and higher T and E in men and women. Variability was large and differed by gender/sex. Implications include strong gum-assay immunoreactivity, the importance of gender/sex in methodological investigations, and that immunoreactivity can differ in degree and direction depending on analytes. PMID:19615825

  3. Design and evaluation of fast dissolving tablets containing diclofenac sodium using fenugreek gum as a natural superdisintegrant

    PubMed Central

    Kumar, M. Uday; Babu, M. Kishore

    2014-01-01

    Objective To formulate diclofenac sodium as fast dissolving tablets (FDTs) using fenugreek gum as a natural superdisintegrant which also possess anti-inflammatory activity. Methods An attempt was made to extract the fenugreek gum and evaluated it for various physicochemical characterizations. The swelling index and viscosity of fenugreek gum was 221% and 293.4 mpa.s respectively. FDTs of diclofenac sodium was formulated by direct compression technique using different concentrations (1%-6%, w/w) of fenugreek gum as a natural superdisintegrant and compared with renowned synthetic superdisintegrants like sodium starch glycolate and croscarmellose sodium. The anti-inflammatory activity of a formulation was evaluated with carrageenan induced experimental rats. Results The formulated tablets were evaluated for various physical tests like weight variation, friability, hardness and results complied with the limits. The drug release from all the formulations ascertained first order kinetics. Among all the formulations F3 containing fenugreek gum with the concentration of 6% produced least disintegrating time 21 seconds resulting in higher drug release rate 93.74% at the end of 25 min. Hence, it was considered as optimized formulation. The present study revealed that the fenugreek gum as a natural superdisintegrant showed better disintegrating property than the most widely used synthetic superdisintegrants like sodium starch glycolate and croscarmellose sodium in the formulations of FDTs. Conclusions The results suggested that the fenugreek gum act as a good super disintegrating agent and it showed promising additive anti-inflammatory activity with diclofenac sodium. PMID:25183106

  4. Gum mastic inhibits the expression and function of the androgen receptor in prostate cancer cells.

    PubMed

    He, Mei-Lan; Yuan, Hui-Qing; Jiang, An-Li; Gong, Ai Yu; Chen, Wei-Wen; Zhang, Peng-Ju; Young, Charles Y F; Zhang, Jian-Ye

    2006-06-15

    Accumulating evidence suggests that the androgen receptor (AR) may play an important role in the development and progression of prostate cancer. To find new, useful compounds that effectively may attenuate the function of AR in prostate cancer cells, the authors investigated the effect of gum mastic, a natural resin, on AR activity. An androgen-responsive prostate cancer cell line LNCaP was used as a model for this study. Gene transfer, reverse transcriptase-polymerase chain reaction analysis, electrophoretic mobility shift assay, and Western blot analysis were used to test the effect of gum mastic on the expression and function of the AR. To demonstrate the inhibitory effect of gum mastic on the function of the AR, the expression of androgen-regulated genes, including prostate-specific antigen (PSA), human kallikrein 2 (hK2), and NKX3.1 were measured. In addition, transient transfection assays with the PSA promoter and the AR promoter also were used to test the effects of mastic. The results showed that gum mastic inhibited the expression of the AR at the transcriptional level, resulting in the down-regulation of both AR messenger RNA and protein levels. Therefore, the function of the AR was inhibited, as reflected by the reduced expression of NKX3.1 and PSA and by androgen-stimulated growth. Because gum mastic exhibited a strong in vitro potency to attenuate the expression and function of the AR, further investigation will be required to determine whether this naturally occurring substance has in vivo potency to inhibit prostate cancer development. PMID:16691616

  5. SUGAR-FREE CHEWING GUM AND DENTAL CARIES – A SYSTEMATIC REVIEW

    PubMed Central

    Mickenautsch, Steffen; Leal, Soraya Coelho; Yengopal, Veerasamy; Bezerra, Ana Cristina; Cruvinel, Vanessa

    2007-01-01

    Objective: To appraise existing evidence for a therapeutic / anti-cariogenic effect of sugar-free chewing gum for patients. Method: 9 English and 2 Portuguese databases were searched using English and Portuguese keywords. Relevant articles in English, German, Portuguese and Spanish were included for review. Trials were excluded on lack of randomisation, control group, blinding and baseline data, drop out rate >33%, no statistical adjustment of baseline differences and no assessment of clinically important outcomes. Reviews were excluded on lack of information, article selection criteria, search strategy followed, search keywords, searched databases or lack of study-by-study critique tables. In cases of multiple reports from the same study, the report covering the longest period was included. Two reviewers independently reviewed and assessed the quality of accepted articles. Results: Thirty-nine articles were included for review. Thirty were excluded and 9 accepted. Of the 9 accepted, 2 trials of reasonable and good evidence value did not demonstrate any anti-cariogenic effect of sugar-free chewing gum. However, 7 articles, with 1 of strong, and 6 of good evidence value, demonstrated anti-cariogenic effects of chewing Sorbitol, Xylitol or Sorbitol/Xylitol gum. This effect can be ascribed to saliva stimulation through the chewing process, particularly when gum is used immediately after meals; the lack of sucrose and the inability of bacteria to metabolize polyols into acids. Conclusion: The evidence suggests that sugar-free chewing gum has a caries-reducing effect. Further well-designed randomised trials are needed to confirm these findings. PMID:19089107

  6. Rate and yield relationships in the production of xanthan gum by batch fermentations using complex and chemically defined growth media

    SciTech Connect

    Pinches, A.; Pallent, L.J.

    1986-10-01

    Rate and yield information relating to biomass and product formation and to nitrogen, glucose and oxygen consumption are described for xanthan gum batch fermentations in which both chemically defined (glutamate nitrogen) and complex (peptone nitrogen) media are employed. Simple growth and product models are used for data interpretation. For both nitrogen sources, rate and yield parameter estimates are shown to be independent of initial nitrogen concentrations. For stationary phases, specific rates of gum production are shown to be independent of nitrogen source but dependent on initial nitrogen concentration. The latter is modeled empirically and suggests caution in applying simple product models to xanthan gum fermentations. 13 references.

  7. The nearby Galaxy structure toward the Vela Gum nebula

    NASA Astrophysics Data System (ADS)

    Giorgi, E. E.; Solivella, G. R.; Perren, G. I.; Vázquez, R. A.

    2015-10-01

    We report on UBVI photometry and spectroscopy for MK classification purposes carried out in the fields of five open clusters projected against the Vela Gum in the Third Galactic Quadrant of the Galaxy. They are Ruprecht 20, Ruprecht 47, Ruprecht 60, NGC 2660 and NGC 2910. We could improve/confirm the parameters of these objects derived before. Ruprecht 20 is not a real physical entity, in agreement with earlier suggestions. Ruprecht 47, a young cluster in the Galactic plane, at 4.4 kpc from the Sun is quite farther than in previous distance estimations and becomes, therefore, a member of the Puppis OB2 association. For the first time Ruprecht 60 was surveyed in UBVI photometry. We found it to be placed at 4.2 kpc from the Sun of about and 1 Gyr old. NGC 2660 is another old object in our survey for which distance and age are coincident with previous findings. NGC 2910 turns out to be a young cluster of Vela OB1 association at a distance of 1.4 kpc approximately and 60 Myr old. The spectroscopic parallax method has been applied to several stars located in the fields of four out of the five clusters to get their distances and reddenings. With this method we found two blue stars in the field of NGC 2910 at distances that make them likely members of Vela OB1 too. Also, projected against the fields of Ruprecht 20 and Ruprecht 47 we have detected other young stars favoring not only the existence of Puppis OB1 and OB2 but conforming a young stellar group at ? 1 kpc from the Sun and extending for more than 6 kpc outward the Galaxy. If this is the case, there is a thickening of the thin Galactic disk of more than 300 pc at just 2-3 kpc from the Sun. Ruprecht 60 and NGC 2660 are too old objects that have no physical relation with the associations under discussion. An astonishing result has been the detection in the background of Ruprecht 47 of a young star at the impressive distance of 9.5 kpc from the Sun that could be a member of the innermost part of the Outer Arm. Another far young star in the field of NGC 2660, at near 6.0 kpc, may become a probable member of the Perseus Arm or of the inner part of the Local Arm. The distribution of young clusters and stars onto the Third Galactic Quadrant agrees with recent findings concerning the extension of the Local Arm as revealed by parallaxes of regions of star formation. We show evidences too that added to previous ones found by our group explain the thickening of the thin disk as a combination of flare and warp.

  8. Magnetic fields in cometary globules. I. CG 22

    Microsoft Academic Search

    T. K. Sridharan; H. C. Bhatt; J. Rajagopal

    1996-01-01

    The authors report first results from a programme to study magnetic fields in cometary globules (CGs). These are clouds near massive stars showing a head-tail morphology. Linear optical polarization measurements on stars seen projected on CG 22 in the Gum-Vela region are presented. A majority of the stars seen within the boundary of the cloud show a polarization of ?1

  9. Factors affecting maturation of avocado somatic embryos

    Microsoft Academic Search

    a Centro de Investigación

    The effect of mineral salts, sucrose, gellan gum, abscisic acid and coconut water on maturation of avocado (Persea americanaMill.) somatic embryos was studied. Use of B5 major salts was essential to obtain white-opaque embryos. Sucrose at 175 mM, gellan gum (6.8 g l?1) or coconut water (10-20%) also enhanced the recovery of white-opaque embryos. Abscisic acid slightly enhanced the appearance

  10. Collagen-poly(dialdehyde) guar gum based porous 3D scaffolds immobilized with growth factor for tissue engineering applications.

    PubMed

    Ragothaman, Murali; Palanisamy, Thanikaivelan; Kalirajan, Cheirmadurai

    2014-12-19

    Here we report the preparation of collagen-poly(dialdehyde) guar gum based hybrid functionalized scaffolds covalently immobilized with platelet derived growth factor - BB for tissue engineering applications. Poly(dialdehyde) guar gum was synthesized from selective oxidation of guar gum using sodium periodate. The synthesized poly(dialdehyde) guar gum not only promotes crosslinking of collagen but also immobilizes the platelet derived growth factor through imine bonds. The covalent crosslinking formed in collagen improves thermal, swelling and biodegradation properties of the hybrid scaffolds. The prepared hybrid scaffolds show 3D interconnected honeycomb porous structure when viewed under a microscope. The release of immobilized platelet derived growth factor was seen up to 13th day of incubation thereby proving its sustained delivery. The developed hybrid scaffold leads to a quantum increase in NIH 3T3 fibroblast cell density and proliferation thereby demonstrating its potential for tissue engineering applications. PMID:25263907

  11. 77 FR 39210 - Xanthan Gum From Austria and the People's Republic of China: Initiation of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ...According to Petitioner, lysine and MSG are both produced via fermentation, use similar production equipment as that required to produce...salts. Xanthan gum is a polysaccharide produced by aerobic fermentation of Xanthomonas campestris. The chemical structure of...

  12. Production of drum-dried jackfruit ( Artocarpus heterophyllus) powder with different concentration of soy lecithin and gum arabic

    Microsoft Academic Search

    C. K. Pua; N. Sheikh Abd. Hamid; G. Rusul; R. Abd. Rahman

    2007-01-01

    The aim of the present study was to determine the optimum concentration of soy lecithin and gum arabic in producing drum-dried jackfruit (Artocarpus heterophyllus) powder using response surface methodology (RSM). Jackfruit puree was dried using a double drum drier set at 1rpm, drum clearance of 0.01in., and steam pressure of 2.3bar. Soy lecithin and gum arabic were incorporated into jackfruit

  13. The effects of chewing frequency and duration of gum chewing on salivary flow rate and sucrose concentration.

    PubMed

    Dong, C; Puckett, A D; Dawes, C

    1995-07-01

    On ten separate occasions, unstimulated saliva was collected from 12 adults and then eight samples of saliva over a 20-min period while chewing, in random order, 3 g of either Wrigley's Spearmint chewing-gum or gum-base at frequencies of 35, 50, 70, 90, or 130 chews/min. With both stimuli, flow rates peaked in the first minute of stimulation and then fell with time. A repeated-measures analysis of variance showed that for both the gum and the gum-base, flow rates were independent of chewing frequency, except during the first minute with the chewing-gum. The gum elicited a significantly higher flow rate over the first 4 min of chewing, while the base elicited a significantly higher flow rate over the 8-20-min period of chewing. The sucrose concentration in saliva was also independent of chewing frequency. The salivary sucrose concentration peaked during the second minute of chewing (mean +/- SE = 424.7 +/- 20.0 mM) and the concentration then fell progressively with time. However, sucrose was still being released into saliva during the 15-20 min period of chewing (12.6 +/- 0.8 mM). Gum-base which had been chewed without access to saliva was softer than unchewed base but showed no change in filler content or a reduction in the average molecular weight. The decrease in hardness of the chewed gum-base may have resulted from improved mixing of heterogeneous phases and increased dispersion of plasticizing agents. PMID:7503931

  14. Seed priming with plant gum biopolymers enhances efficacy of metalaxyl 35 SD against pearl millet downy mildew

    Microsoft Academic Search

    J. Sudisha; S. Niranjan-Raj; H. Shekar Shetty

    2009-01-01

    ‘Priming’ the plant and seed induces a physiological state in which plants are able to activate defense responses. Plant-based\\u000a exudates are excellent gum biopolymers which contain plant growth-regulating hormones with priming potential without any side\\u000a effects. In this study, gum exudates of Acacia arabica, Moringa oleifera, Carica papaya and Azadirachta indica were evaluated for synergistic effects of seed priming with

  15. STUDIES OF MIXING IN A CONCENTRIC TUBE AIRLIFT REACTOR CONTAINING XANTHAN GUM BY MEANS OF AN IMPROVED FLOW FOLLOWER

    Microsoft Academic Search

    P. R. FIELDS; F. R. G. MITCHELL; N. K. H. SLATER

    1984-01-01

    The influence of a pseudoplastic non-Newtonian fluid upon the hydrodynamic performance and mixing parameters of a concentric tube air-lift fermenter has been studied using a range of dilute xanthan gum solutions (0-0.5% weight by volume). Liquid circulation times vary in a complex pattern with increasing gum concentration. At low concentrations, circulation was more; rapid due to drag reduction whilst at

  16. Xanthan and locust bean gum influence on the rheology and structure of a white model-sauce

    Microsoft Academic Search

    I. G Mandala; T. P Savvas; A. E Kostaropoulos

    2004-01-01

    Xanthan and locust bean gum (LBG) were added in a white “model-sauce”. The following samples were prepared: control samples containing gelatinized corn starch, casein, and olive oil and samples containing additionally 0.09%, 0.15% and 0.25% (w\\/w) xanthan gum, or 0.09% (w\\/w) LBG. The samples were stored at 5 °C for 15 days, and during storage, static and dynamic rheological experiments

  17. Effect of guar gum upon the partition coefficients of diacetyl, acetaldehyde, and ethanol in acidified milk products

    E-print Network

    Lo, Chih-Yang

    1992-01-01

    EFFECT OF GUAR GUM UPON THE PARTITION COEFFICIENTS OF DIACE~ ACETALDEHYDE& AND ETHANOL IN ACIDIFIED MILK PRODUCTS A Thesis by CHIH- YANG LO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE December 1992 Major Subject: Food Science and Technology EFFECT OF GUAR GUM UPON THE PARTITION COEFFICIENTS OF DIACETYL, ACETALDEHYDE, AND ETHANOL IN ACIDIFIED MILK PRODUCTS A Thesis by Chih- Yang Lo...

  18. The effect of two types chewing gum containing casein phosphopeptide-amorphous calcium phosphate and xylitol on salivary Streptococcus mutans

    PubMed Central

    Emamieh, Shila; Khaterizadeh, Yosra; Goudarzi, Hossein; Ghasemi, Amir; Baghban, Alireza Akbarzadeh; Torabzadeh, Hasan

    2015-01-01

    Aim: The aim was to evaluate the effect of sugar-free chewing gum containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and xylitol on salivary Streptococcus mutans. Materials and Methods: A total of 60 dental students of 20-25 years old, who volunteered after checking their health condition and signing an informed consent, were randomly allocated to receive one of the following interventions: (A) Chewing gum containing CPP-ACP; (B) containing xylitol. Subjects within the experimental groups were taken the gums 3 times daily, after each meal for a period of 3 weeks. Pre- and post-intervention unstimulated saliva samples were quantified for S. mutans counts. Results: A statistically significant reduction of salivary S. mutans was displayed in both groups A and B after the intervention when compared with baseline (P < 0.001), and group A shows more statistically significant reduction of salivary S. mutans than group B (P = 0.011). Conclusion: Daily consumption of chewing gum containing CPP-ACP and xylitol significantly reduces the level of salivary S. mutans, but chewing gum containing CPP-ACP can reduce the level of salivary S. mutans in more than xylitol chewing gum.

  19. The use of xanthan gum in an ophthalmic liquid dosage form: rheological characterization of the interaction with mucin.

    PubMed

    Ceulemans, Jens; Vinckier, Inge; Ludwig, Annick

    2002-04-01

    The development of an ocular dosage form containing xanthan gum and capable of interacting with mucin in the precorneal area is a challenge. The polymer concentration that can be applied is restricted because of the limited patient acceptability of highly viscous preparations. The precorneal mucin concentration is low and the high ionic strength of the lachrymal fluid forces xanthan gum in an ordered structure, less capable of interacting through heterotypic junctions. Intrinsic viscosity measurements and shear rheometry are used to investigate the effect of several factors (polymer concentration, additional boiling or sonication step to the preparation procedure) on the physicochemical properties of xanthan gum and the degree of interaction with a low (8%, w/v) and high (16.0%, w/v) concentrated mucin dispersion. Independent of the preparation procedure applied, a xanthan gum concentration of 1.0% (w/v) is required to obtain a measurable interaction with mucin. If an extra boiling or sonication step is added to the standard preparation procedure, the minimum mucin concentration necessary to achieve formation of heterotypic junctions is decreased. Only by sonication of the highly concentrated xanthan gum dispersion is the viscosity decreased to a level that is tolerable and comfortable to the patient. The findings of the present study clearly demonstrate that a significant interaction between a tolerable and comfortable ocular dosage form containing xanthan gum, and mucin 8% (w/v), is feasible after sonication of a highly concentrated polymer dispersion. PMID:11948550

  20. Effect of dynamic high pressure on technological properties of cashew tree gum (Anacardium occidentale L.).

    PubMed

    Porto, Bruna Castro; Augusto, Pedro E D; Terekhov, Anton; Hamaker, Bruce R; Cristianini, Marcelo

    2015-09-20

    Dynamic high pressure (DHP) appears to be an alternative approach to physical modification of polysaccharides aimed improving their technological properties. Therefore, its effect on the functional properties of polysaccharides (i.e., oil absorption capacity, emulsifier, and rheology) needs to be investigated. Cashew tree gum (CG) is a biological macromolecule that has been proposed to be used as an emulsifier in beverage emulsions. To the best of our knowledge, none of the articles in the literature investigates the effect of DHP on the CG properties. This work presents a study on the evaluation of the effects of DHP on functional characteristics of CG, including rheological properties, molecular weight, glycosyl-linkage analysis, solubility, swelling and oil absorption capacity (OAC). The results suggest that DHP is able to modify the technological properties of cashew tree gum (increasing solubility and decreasing apparent viscosity). PMID:26050904

  1. Graft copolymerization of ethylacrylate onto xanthan gum, using potassium peroxydisulfate as an initiator.

    PubMed

    Pandey, Sadanand; Mishra, Shivani B

    2011-11-01

    Graft copolymer of xanthan gum (XG) and ethylacrylate (EA) has been synthesized by free radical polymerization using potassium peroxydisulfate (KPS) as an initiator in an air atmosphere. The grafting parameters, i.e. grafting ratio and efficiency decrease with increase in concentration of xanthan gum from 0.050 mg/25 mL to 0.350 mg/25 mL, but these grafting parameters increase with increase in concentration of ethylacrylate from 9×10(-2) to 17×10(-2) ML(-1), and KPS from 15×10(-3) to 35×10(-3) ML(-1). The graft copolymer has been characterized by FTIR, XRD, TGA and SEM analysis. The grafted copolymer was also evaluated as efficient Zn(2+) metal binder. The grafted copolymer shows improvement in the stability, solubility as well as their sorbing capacity. Thus graft copolymer formed could find applications in metal ion removal and in drug delivery. PMID:21693131

  2. Synthesis, characterization of thiolated karaya gum and evaluation of effect of pH on its mucoadhesive and sustained release properties.

    PubMed

    Bahulkar, Swati S; Munot, Neha M; Surwase, Sachin S

    2015-10-01

    Present study aims at synthesis and characterization of thiolated gum karaya by reacting karaya gum with 80% thioglycolic acid resulting in esterification and immobilization of thiol groups on polymeric backbone. Immobilized thiol groups were found to be 5.026mM/g determined by Ellman's method. It was characterized by FTIR, DSC and XRD. Directly compressible tablets prepared using thiolated gum displayed more disintegration time, swelling and mucoadhesion with increase in pH of medium simulating gastric and intestinal environment than plain gum. Controlled drug release for more than 24h by Fickian diffusion following Korsemeyer-Peppas model was observed with Metoprolol Succinate as a model drug as compared to plain gum which released more than 90% of the drug within 2h. Synthesized thiomer showed no cytotoxicity determined using HepG2 cell line. According to these results, thiolated gum karaya seems to be promising excipient for the development of mucoadhesive drug delivery systems. PMID:26076615

  3. Mastic gum has no effect on Helicobacter pylori load in vivo

    Microsoft Academic Search

    James R. Bebb; Nathalie Bailey-Flitter; Dlawer Ala' Aldeen; John C. Atherton

    Objective: To determine whether mastic gum suppresses or eradicates Helicobacter pylori infection in humans. Patients and methods: Nine patients with H. pylori infection, and without gastroduodenal ulceration, were recruited from day-case endoscopy lists and treated with mastic 1 g four times daily for 14 days. (13C)Urea breath tests (UBTs) were carried out immediately before, on day 15 and 5 weeks

  4. Allergic contact dermatitis due to 1,2-benzisothiazolin-3-one in gum arabic.

    PubMed

    Freeman, S

    1984-09-01

    Benzisothiazolin-3-one is a preservative widely used in industry. The manufacturer states that it is a known skin irritant and sensitiser, but these facts are not well-known. A case is described of contact allergy in a lithoprinter caused by it when used as a preservative in gum arabic. The literature is reviewed and a suitable patch-test concentration is suggested. It should be included in the patch-test battery for lithoprinters. PMID:6238787

  5. The relative bioavailability of loratadine administered as a chewing gum formulation in healthy volunteers

    Microsoft Academic Search

    Lene Noehr-Jensen; Per Damkier; Tanja Busk Bidstrup; Rasmus Steen Pedersen; Flemming Nielsen; Kim Brosen

    2006-01-01

    Objective  The aim of this study was to investigate the pharmacokinetics of loratadine and its active metabolite desloratadine after single-dose administration of loratadine as a conventional tablet, orally disintegrating tablet (smelt tablet) and a chewing gum formulation with and without the collection of saliva.Methods  Twelve healthy male volunteers participated in a four-period cross-over trial evaluating the effect of dosage forms on the

  6. Xanthan gum: an economical partial substitute for agar in microbial culture media.

    PubMed

    Babbar, Shashi B; Jain, Ruchi

    2006-04-01

    Xanthan gum, microbial desiccation-resistant polysaccharide prepared commercially by aerobic submerged fermentation from Xanthomonas campestris, has been successfully used alone and in combination with agar for microbial culture media. As illustrative examples, eight bacteria and eight fungi were grown on media solidified with either agar (A, 1.5%), xanthan gum (X, 1%), or combinations of both (0.9% X + 0.1% A, 0.8% X + 0.2% A, 0.7% X + 0.3% A, 0.6% X + 0.4% A). All fungi and bacteria exhibited normal growth and differentiation in all these treatments. Rather, growth of most of the fungi was better on xanthan (alone) and xanthan + agar media than agar medium. As the media gelled with xanthan gum alone flow, it was not possible to incubate Petri plates in inverted position. Moreover, because of the softness, streaking of bacteria was difficult on such media. However, these problems could be overcome by partially replacing xanthan gum with 0.3% agar. Bacterial enumeration studies carried out for Serratia sp. and Pseudomonas sp. by serial dilution and pour-plate method on agar (1.5%), 0.7%/0.6% X + 0.3%/0.4% A yielded similar counts. Selective media, succinate medium for Pseudomonas sp., and MacConkey broth medium for Escherichia coli gelled with 0.7%/0.6% X + 0.3%/0.4% A did not support growth of other bacteria when inoculated along with the above-mentioned bacteria. Likewise, differential medium, CRMA (Congo red mannitol agar) gelled with xanthan-agar combination could differentiate between Agrobacterium tumefaciens and Rhizobium sp. PMID:16550465

  7. Review of xanthan gum production from unmodified starches by Xanthomonas comprestris sp

    Microsoft Academic Search

    S. Rosalam; R. England

    2006-01-01

    Many attempts were reported to optimise variables in xanthan gum fermentations, i.e. the nutrient composition and feeding technique, temperature, pH, agitation, and adding antifoam. All shows some improvement in the area studied. Other substrates were also tested, such as hydrolysed rice, barley and corn flour, acid whey and sugarcane molasses, etc., but glucose is still the best in-term of the

  8. Supermolecular aspects of xanthan-locust bean gum gels based on rheology and electron microscopy

    Microsoft Academic Search

    Leif Lundin; Anne-Marie Hermansson

    1995-01-01

    The viscoelastic properties and supermolecular structure of synergistic gels, formed by xanthan and locust bean gum (LBG) of two different mannose:galactose ratios (M:G), have been investigated by small deformation viscoelastic measurements and by low angle rotary-shadowing for transmission electron microscopy.The rheological properties at 20 °C for mixtures subjected to heating and cooling cycles in the temperature range 30–80 °C were

  9. Gummosis in grape hyacinth ( Muscari armeniacum ) bulbs: hormonal regulation and chemical composition of gums

    Microsoft Academic Search

    Kensuke Miyamoto; Toshihisa Kotake; Makiko Sasamoto; Marian Saniewski; Junichi Ueda

    2010-01-01

    The purpose of this study was to investigate the hormonal regulation of gummosis in grape hyacinth (Muscari armeniacum) bulbs, focusing especially on the chemical composition of the gums. The application of ethephon (2-chloroethylphosphonic\\u000a acid), an ethylene-releasing compound, at 1% and 2% (w\\/w) in lanolin as well as ethylene induced gummosis in the bulbs within\\u000a several days. Methyl jasmonate (JA-Me, 0.1–2%

  10. Studies on the steady shear flow behavior and functional properties of Lepidium perfoliatum seed gum

    Microsoft Academic Search

    Arash Koocheki; Ali Reza Taherian; Aram Bostan

    Flow properties of Lepidium perfoliatum gum, extracted from Qodume shahri seeds, as influences of concentrations (0.5%, 1%, 1.5% and 2%), temperatures (5, 25, 45, and 65°C), salts and pHs were investigated. Among the selected models, power law model well described the rheological behavior of the L. perfoliatum seed mucilage solutions with high determination coefficients, R2 and low root mean square

  11. Citrus psorosis, ringspot, cristacortis and concave gum pathogens are maintained in callus culture

    Microsoft Academic Search

    J. Navas-Castillo; P. Moreno; N. Duran-Vila

    1995-01-01

    Callus cultures were established from citrus explants infected with several virus-like pathogens of the psorosis group (psorosis A, psorosis B, ringspot, cristacortis, or concave gum), and successively subcultured for up to 16 months. ‘Pineapple’ sweet orange or ‘Duncan’ grapefruit seedlings graft-inoculated with callus pieces, and incubated in a temperature-controlled greenhouse, developed symptoms characteristic of these diseases, whereas similar indicator plants

  12. Hepatoprotective prenylaromadendrane-type diterpenes from the gum resin of Boswellia carterii.

    PubMed

    Wang, Yan-gai; Ren, Jin; Wang, Ai-guo; Yang, Jian-bo; Ji, Teng-fei; Ma, Qin-Ge; Tian, Jin; Su, Ya-lun

    2013-11-22

    Chemical examination of the exuded gum resin of Boswellia carterii resulted in the isolation of nine new prenylaromadendrane-type diterpenes, boscartols A-I (1-9). The structures of these compounds were established by extensive 1D and 2D NMR spectroscopic analyses, mass spectrometric data, and circular dichroism spectra. Compounds 1-3, 5, 6, 8, and 9 (10 ?M) showed moderate hepatoprotective activity against d-galactosamine-induced HL-7702 cell damage. PMID:24195447

  13. A Unique Method of Retention for Gum Stripper- A Case Report

    PubMed Central

    T.S., Priyanka

    2014-01-01

    Successful restoration of partially edentulous situations, especially kennedy’s class-I, II &IV requires lot of contemporary and conventional treatment approaches. Semi precision attachments play a major role in retention of clinically challenging partially edentulous situation. Attachment retained partial dentures can be one of the successful treatment option in prosthdontics. This article presents a unique technique of retaining gum stripper using semi precision attachments. PMID:25654046

  14. Diameter prediction mathematical models for xanthan gum-alginate capsules produced by extrusion-dripping method

    NASA Astrophysics Data System (ADS)

    Ong, Hui-Yen; Lee, Boon-Beng; Zakaria, Zarina; Chan, Eng-Seng

    2015-05-01

    The aim of this work is to compare the applicability of particle diameter prediction mathematical models (i.e. Tate's Law equation, the modified Tate's Law equation, the modified Yildirim's model) to determine diameter of liquid core capsules. The capsules were produced by extruding xanthan gum-calcium chloride solution through a hypodermic needle into sodium alginate solution. The effects of two types of xanthan gum with different concentrations and needle diameters on capsule diameter were investigated in this work. The results showed that there was no significant difference in capsule diameter despite different types and concentrations of xanthan gum were used. However, the diameter of the capsules increased when the diameter of needles increased. As a whole, the produced capsules were in the range of 3.47 mm to 4.86 mm. Among the three studied prediction models, the modified Tate's Law mathematical equation was the most suitable model for the diameter prediction of the liquid core capsules with AAD of 2.74% and MAD of 6.55%.

  15. [Chewing gum as an additional agent in maintaining oral hygiene versus smoking status--preliminary study].

    PubMed

    Nakonieczna-Rudnicka, Marta; Strycharz-Dudziak, Ma?gorzata; Bachanek, Teresa

    2012-01-01

    Nowadays chewing gum is widely used in different age groups, so complying with proper duration and frequency of chewing is an important factor influencing the state of masticatory system. The study involved 112 dental students of the Medical University of Lublin. Everyday use of chewing gum declared 47,32% of cases. Chewing time up to 10 minutes was stated in 23,08% of respondents, 11-20 minutes in 40,38% of interviewees. Among the examined students 17,3% smoked cigarettes. In smokers group 83,33% of questioned chewed the gum every day, while among non-smokers - 43,37%. Chewing time shorter than 10 minutes declared 22,22% of smokers and 23,26% of non-smokers, while chewing time between 11-20 minutes - 27,78% i 44,35% of smokers and non-smokers respectively. Obtained results indicate the need of carrying out further studies aimed at the nicotine influence on saliva parameters with respect to development of diseases of hard tooth tissues. PMID:23421028

  16. Synthesis of partially hydrolyzed graft copolymer (H-Ipomoea hederacea seed gum-g-polyacrylonitrile).

    PubMed

    Yadav, Mithilesh; Singh, Somit Kumar; Rhee, Kyong Yop

    2013-06-01

    Polyacrylonitrile was grafted to Ipomoea hederacea (Ih) seed gum with 138.5% grafting yield and 43.55% grafting efficiency in a procedure that was performed under homogeneous microwave (MW) irradiation conditions for 70s in the absence of a radical initiator. Under similar conditions, a maximum grafting yield of 108% and 33.96% efficiency was achieved when the K2S2O8/ascorbic acid redox system was used as a radical initiator in a thermostatic water bath at 35 °C. The effects of reaction variables, such as monomer/Ih seed gum concentration, MW power, and exposure time on the graft copolymerization were studied. The partially hydrolyzed graft copolymer (H-Ih-g-PAN) formed a loose, porous surface and improved the water absorbency of Ih seed gum. The swelling behavior of H-Ih-g-PAN in various ionic salt (NaCl, MgCl2 and Na2SO4) solutions was also systematically investigated. The graft copolymer was further characterized using FTIR, TGA, XRD, and SEM. PMID:23618295

  17. Effect of sugars and salts on rheological properties of Balangu seed (Lallemantia royleana) gum.

    PubMed

    Salehi, Fakhreddin; Kashaninejad, Mahdi; Behshad, Vahid

    2014-06-01

    The effect of different sugars (sucrose, glucose, fructose, and lactose) and salts (NaCl and CaCl2) at various concentrations on rheological properties of Balangu seed gum (BSG, 1% w/w) was investigated. The apparent viscosity was influenced by the sugars and salts concentration and shear rate. Synergistic interaction between BSG gum and sugars improved the viscosity of solutions, whereas addition of salts decreased viscosity of gum solutions. The Power law and Herschel-Bulkley models were fitted to shear stress-shear rate data to obtain the consistency coefficient (K) and flow behavior index (n) for BSG solutions. Power law model well described non-Newtonian pseudoplastic behavior of BSG. Both K and n were sensitive to sugars and salts concentration. Highest values (0.45-0.49) of flow behavior index were observed for glucose at all concentrations. Addition of sucrose, fructose, lactose and salts to BSG led to more pseudoplastic solutions, whereas glucose decreased pseudoplasticity of solutions. PMID:24631549

  18. Potential use of curcumin loaded carboxymethylated guar gum grafted gelatin film for biomedical applications.

    PubMed

    Manna, Piyali Jana; Mitra, Tapas; Pramanik, Nilkamal; Kavitha, V; Gnanamani, A; Kundu, P P

    2015-04-01

    Present study describes the synthesis of carboxylmethyl guar gum (CMGG) from the native guar gum (GG). Further, the prepared CMGG is grafted with gelatin to form CMGG-g-gelatin and then mixed with curcumin to prepare a biomaterial. The resultant biomaterial is subjected to the analysis of (1)H NMR, ATR-FTIR, TGA, SEM and XRD ensure the carboxymethylation and grafting. The results reveal that 45% of the amine groups of gelatin have been reacted with the--COOH group of CMGG and 90-95% of curcumin is released from CMGG-g-gelatin after 96h of incubation in the phosphate buffer at physiological pH. In vitro cell line studies reveal the biocompatibility of the biomaterial and the antimicrobial studies display the growth inhibition against gram +ve and gram -ve organisms at a considerable level. Overall, the study indicates that the incorporation of curcumin into CMGG-g-gelatin can improve the functional property of guar gum as well as gelatin. PMID:25661877

  19. Rheological and kinetic study of the ultrasonic degradation of xanthan gum in aqueous solutions.

    PubMed

    Li, Ruoshi; Feke, Donald L

    2015-04-01

    The effectiveness of ultrasound to degrade the molecular weight of xanthan gum in aqueous solutions was investigated for sonication times up to 60 min at 20 °C and for polymer concentrations up to 0.1g/dl. The Huggins equation was found to be applicable to the intrinsic viscosity of xanthan gum prior to sonication, while a truncated form was found to be adequate for estimating the intrinsic viscosity of the degraded xanthan. To better understand the influence of salting-in and salting-out salts (classified on the basis of the Hofmeister series) on degradation, xanthan-gum solutions were pre-mixed with 0.1, 10(-2), 10(-3), or 10(-4)M NaCl or Na2SO4, prior to ultrasonication. A kinetic model was developed and successfully applied to quantify and predict the degradation rates and efficiency. The various reaction rate constants and reaction orders were found to correlate with the different salt species and concentrations used, suggesting that salting-in and salting-out salts could increase or inhibit ultrasonic degradation by adjusting the molecular conformation of the xanthan. PMID:25442624

  20. Chemical structure of the arabinogalactan protein from gum ghatti and its interaction with bovine serum albumin.

    PubMed

    Ghosh, Kanika; Ray, Sayani; Ghosh, Debjani; Ray, Bimalendu

    2015-03-01

    Exudate gums, because of their beneficial properties, have been significant items of international trade in various industries for centuries. This manuscript sets out to gain insight into the fine structural details of an arabinogalactan protein (AGP) of gum ghatti (Anogeissus latifolia gum). The presence of a highly branched 554 kDa AGP having 1,6-linked Galp, 1,2-linked Manp, 1,3-linked Araf and 1,4-linked GlcpA main chain, substituted at O-4,6 of 1,2-linked Manp, and O-3/O-3,4 of 1,6-linked Galp residues by Araf, Arap and Galp units was revealed by chemical, chromatographic, ESMS, and NMR analyses. In particular, ESMS analysis of per acetylated oligomeric fragments derived from AGP by Smith degradation followed by acetylation was described as a commanding tool for providing critical structural information on a spectrum of glycerol tagged oligosaccharides. In addition, formation of an electrostatically driven complex between the isolated AGP and bovine serum albumin resulting in changes in the microenvironment around the tryptophan residues of BSA was established. A moderate radical scavenging activity comparable with those of standard antioxidants was observed from the AGP fraction (?94% at 1 mg/mL) that could be valuable in foods or pharmaceutical products as alternatives to synthetic antioxidants. PMID:25498648

  1. Formulation and In Vitro Evaluation of Ofloxacin Tablets using Natural Gums as Binders.

    PubMed

    Mistry, Amisha K; Nagda, Chirag D; Nagda, Dhruti C; Dixit, Bharat C; Dixit, Ritu B

    2014-06-01

    Natural gums are economical, easily available, and useful as tablet binders. In the present investigation, an attempt was made to formulate Ofloxacin tablets using three natural binders, namely Acacia arabica, Hibiscus esculentus, and xanthan gum. Such six batches of Ofloxacin tablets were prepared by using different types and amounts of the natural binders by the wet granulation method. The tablets were analyzed for their hardness, friability, and weight variation, and in vitro release was performed in a phosphate buffer at pH 6.8. The prepared tablets were also evaluated for their various release kinetics and similarity factors f2. The physical properties of the tablets containing the natural binders showed sufficient hardness, desirable disintegration time, and low friability. Their better percentage of drug release was observed as compared to the marketed formulation showing more than 85% drug release within 45 minutes. The in vitro release data was well-fitted into zero-order and the values of release exponent 'n' were between 0.303 and 0.514. The high similarity factor f2 of 64.50 was achieved with the best batch in comparison to the marketed tablets. The results obtained indicated that the gum Acacia arabica performed as well as gelatin compared to the other binders for the Ofloxacin tablet formulation. PMID:24959411

  2. Quantitative analysis of macro and micro-structure of gluten-free rice cakes containing different types of gums baked in different ovens

    Microsoft Academic Search

    Elif Turabi; Gulum Sumnu; Serpil Sahin

    2010-01-01

    The effects of different gums on macro-structure of gluten-free rice cakes baked in conventional and infrared–microwave (IR–MW) combination ovens were investigated by using the images obtained by scanner and scanning electron microscopy in this study. The gum types used were xanthan, guar, locust bean, ?-carrageenan and xanthan–guar blend. Cake containing no gum was used as control. It was observed that

  3. The comparative effect of propolis in two different vehicles; mouthwash and chewing-gum on plaque accumulation and gingival inflammation

    PubMed Central

    Ercan, Nuray; Erdemir, Ebru Olgun; Ozkan, Serdar Yucel; Hendek, Meltem Karsiyaka

    2015-01-01

    Objective: In general, chemical plaque agents have been used in mouthwashes, gels, and dentifrices. In some situations, application of mouthwashes and dentifrices can be difficult. Therefore, different approaches for oral health-care have been needed. The aim of this study was to evaluate the effect of propolis chewing-gum compared to propolis-containing mouthwash on gingival inflammation and plaque accumulation on patients that refrained from daily oral hygiene procedures for 5 days. Materials and Methods: 10 college students with systemically healthy and very good oral hygiene and gingival health were included in this randomized, single-blind, crossover 5-day plaque regrowth with a 3-day washout period clinical study. After plaque scores were reduced to zero, participants were asked to refrain from oral hygiene procedures and allocated to either propolis mouthwash or chewing-gum group. Chewing-gum was performed after meals 3 times a day for 20 min mouthwash group was instructed to rinse mouthwash 2 times a day for 1 min. On day 5, the clinical periodontal measurements containing plaque and gingival indexes were taken from the participants. Results: The both plaque and gingival indexes of propolis mouthwash group were significantly lower than that of the propolis chewing-gum group (P = 0.005). Conclusion: It was demonstrated that the propolis mouthwash was more effective than the propolis chewing gum on the plaque inhibition and the gingival inflammation.

  4. Gas chromatography–mass spectrometric analysis of products from on-line pyrolysis\\/silylation of plant gums used as binding media

    Microsoft Academic Search

    Oscar Chiantore; Chiara Riedo; Dominique Scalarone

    2009-01-01

    Plant gums are complex polysaccharides used in the field of cultural heritage especially as binding media. Classification of polysaccharides may be achieved on the basis of monosaccharides composition after cleavage of glycosidic bond. Characterization of plant gums in works of art is complicated by the necessity of to use a method minimally invasive and requiring a small mount of sample.Pyrolisys

  5. Protective mechanisms for pupae of Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae), a parasitoid of the red-gum lerp psyllid, Glycaspis brimblecombei Moore (Hemiptera: Psylloidea)

    Microsoft Academic Search

    Daniel J Sullivan; Kent M Daane; Karen R Sime; John W Andrews Jr

    2005-01-01

    Psyllaephagus bliteus was imported from Australia in 1999 and released in California in 2000 as part of a classical biological control program targeting the red-gum lerp psyllid, Glycaspis brimblecombei , which in California feeds mainly on red gum, Eucalyptus camaldulensis Dehnh. Psyllaephagus bliteus is an internal parasitoid that delays development until the psyllid host reaches the late fourth or fifth

  6. What Can We Learn from the Saga of Chitosan Gums in Hyperphosphatemia Therapy?

    PubMed Central

    Oh, Man S.

    2014-01-01

    Control of high serum phosphorus, a marker of poor outcome, is still a poorly achieved goal in dialysis therapy. Therefore, the 2009 study (Savica et al., J Am Soc Nephrol 20: 639–644, 2009) showing a significant drop of serum phosphate (2.35 mg/dl) after only 2 weeks of chewing a chitosan-containing gum two times per day was received with great hopes by the renal community. Chitosan is a polymer of glucosamine, similar to sevelamer, which allegedly would bind phosphate present in high concentrations in the saliva of renal patients. Recent randomized studies, however, have been unable to duplicate these results. A systematic and detailed quantitative analysis of the available data was performed. It concluded that the amount of chitosan contained in the chewing gum (20 mg) is too little to account for the originally observed reduction in serum phosphate and be of any use as a phosphate binding agent in the management of hyperphosphatemia. It was postulated that the original marked drop in serum phosphate may have been caused by the Hawthorne effect, which is frequently observed in nonrandomized clinical trials. Two important lessons derived from this analysis are emphasized. The first lesson is the demonstration of the importance of randomized, placebo-controlled studies in clinical research. If randomization had been performed in the original study, the Hawthorne effect would have been detected. The second lesson is showing the importance of quantitative analysis, which in this case, would have avoided the time and effort expended in several randomized clinical trials that eventually concluded the ineffectiveness of the chitosan-containing chewing gums as a phosphate binder. PMID:24408115

  7. Sonication-based improvement of the physicochemical properties of Guar Gum as a potential substrate for modified drug delivery systems.

    PubMed

    Ansari, Siddique Akber; Matricardi, Pietro; Cencetti, Claudia; Di Meo, Chiara; Carafa, Maria; Mazzuca, Claudia; Palleschi, Antonio; Capitani, Donatella; Alhaique, Franco; Coviello, Tommasina

    2013-01-01

    Guar Gum is a natural polysaccharide that, due to its physicochemical properties, is extensively investigated for biomedical applications as a matrix for modified drug delivery, but it is also used in the food industry as well as in cosmetics. A commercial sample of Guar Gum was sonicated for different periods of time, and the reduction in the average molecular weight was monitored by means of viscometric measurements. At the same time, the rheological behaviour was also followed, in terms of viscoelasticity range, flow curves, and mechanical spectra. Sonicated samples were used for the preparation of gels in the presence of borate ions. The effect of borax on the new samples was investigated by recording mechanical spectra, flow curves, and visible absorption spectra of complexes with Congo Red. The anisotropic elongation, observed in previous studies with tablets of Guar Gum and borax, was remarkably reduced when the sonicated samples were used for the preparation of the gels. PMID:23984426

  8. Comparison between classical GUM and Bayesian uncertainty estimation approaches in SPRT calibrations

    NASA Astrophysics Data System (ADS)

    del Campo, D.; García, C.; Ruiz, S.

    2013-09-01

    In this paper a comparison between the results of an uncertainties assessment, using different approaches, of the calibration of Standard Platinum Resistance Thermometers (SPRT) in fixed points are examined. Three different approaches are selected: classical GUM, propagation of probability distribution functions using Monte Carlo method, and the Bayesian approach. They are applied to the mathematical model proposed in the document "Uncertainties in the Realisation of the SPRT subranges of the ITS-90", prepared by the Working Group 3 of the Consultative Committee for Thermometry, and their results are discussed.

  9. Green synthesis, characterization and catalytic activity of palladium nanoparticles by xanthan gum

    NASA Astrophysics Data System (ADS)

    Santoshi kumari, Amrutham; Venkatesham, Maragoni; Ayodhya, Dasari; Veerabhadram, Guttena

    2015-03-01

    Here, we report the synthesis, characterization and catalytic evaluation of palladium nanoparticles (PdNPs) using xanthan gum, acting as both reducing and stabilizing agent without using any synthetic reagent. The uniqueness of our method lies in its fast synthesis rates using hydrothermal method in autoclave at a pressure of 15 psi and at 120 °C temperature by 10 min time. The formation and size of the PdNPs were characterized by UV-visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and transmission electron microscopy. The catalytic activity of PdNPs was evaluated on the reduction of 4-nitrophenol to 4-aminophenol by sodium borohydride using spectrophotometry.

  10. Modeling and steady state simulation: production of xanthan gum from sugarcane broth.

    PubMed

    Vignesh, P; Arumugam, A; Ponnusami, V

    2015-01-01

    The work is focused on developing a mathematical model for continuous process of xanthan gum production. The main objective of the study is to simulate the model, observe the behavior of substrate consumption, biomass and product formation with respect to dilution rate and determine the optimum dilution rate for which the reactor is to be designed. Systems with and without recycling of cells are considered and the optimum dilution rate is found. For the kinetic parameters used, the optimum dilution rate for the system with no recycling is 0.205 and 0.35 h(-1) for the system that includes recycling of cells. PMID:24992981

  11. Encapsulation of endoglucanase using a biopolymer Gum Arabic for its controlled release.

    PubMed

    Ramakrishnan, Anish; Pandit, Nilesh; Badgujar, Mahesh; Bhaskar, C; Rao, Mala

    2007-01-01

    Gum Arabic, a biodegradable natural polymer was used as a matrix to encapsulate endoglucanase from Thermomonospora sp. The modified enzyme retained complete biocatalytic activity and exhibited a shift in the optimum temperature [50-55 degrees C] and considerable increase in the pH and temperature stabilities as compared to the free enzyme. Encapsulation of the enzyme also protected the activity in presence of detergents and enhanced the shelf life. A 3-fold decrease in the initial rate of reaction indicated a controlled release of the enzyme conferring properties preferred for its potential application in the manufacture of detergents. PMID:16481159

  12. Dissolution Improvement of Atorvastatin Calcium using Modified Locust Bean Gum by the Solid Dispersion Technique

    PubMed Central

    Panghal, Dharmila; Nagpal, Manju; Thakur, Gurjeet Singh; Arora, Sandeep

    2014-01-01

    The present research was aimed at the enhancement of the dissolution rate of atorvastatin calcium by the solid dispersion technique using modified locust bean gum. Solid dispersions (SD) using modified locust bean gum were prepared by the modified solvent evaporation method. Other mixtures were also prepared by physical mixing, co-grinding, and the kneading method. The locust bean gum was subjected to heat for modification. The prepared solid dispersions and other mixtures were evaluated for equilibrium solubility studies, content uniformity, FTIR, DSC, XRD, in vitro drug release, and in vivo pharmacodynamic studies. The equilibrium solubility was enhanced in the solid dispersions (in a drug:polymer ratio of 1:6) and other mixtures such as the co-grinding mixture (CGM) and kneading mixture (KM). Maximum dissolution rate was observed in the solid dispersion batch SD3 (i.e. 50% within 15 min) with maximum drug release after 2 h (80%) out of all solid dispersions. The co-grinding mixture also exhibited a significant enhancement in the dissolution rate among the other mixtures. FTIR studies revealed the absence of drug-polymer interaction in the solid dispersions. Minor shifts in the endothermic peaks of the DSC thermograms of SD3 and CGM indicated slight changes in drug crystallinity. XRD studies further confirmed the results of DSC and FTIR. Topological changes were observed in SEM images of SD3 and CGM. In vivo pharmacodynamic studies indicated an improved efficacy of the optimized batch SD3 as compared to the pure drug at a dose of 3 mg/kg/day. Modified locust bean gum can be a promising carrier for solubility enhancement of poorly water-soluble drugs. The lower viscosity and wetting ability of MLBG, reduction in particle size, and decreased crystallinity of the drug are responsible for the dissolution enhancement of atorvastatin. The co-grinding mixture can be a good alternative to solid dispersions prepared by modified solvent evaporation due to its ease of preparation and significant improvement in dissolution characteristics. PMID:24634850

  13. Cycloartanes from the gum resin of Gardenia gummifera L.f.

    PubMed

    Gandhe, Sreekanth; Lakavath, Suryanarayana; Palatheeya, Sujatha; Schuehly, Wolfgang; Amancha, Kalpana; Kiran Reddy Nallamaddi, Ravi; Palepu, Anupama; Thakur, Yogita; Rao Adavi Rao Belvotagi, Venkat; Kumar Bobbala, Ravi; Narasimha Appa Rao Achanta, Venkata; Kunert, Olaf

    2013-09-01

    The gum resin exuding from the leaf buds of Gardenia gummifera was investigated. Eight new cycloartane triterpenes, 1-6, 8, and 10, together with two known triterpenes, 25-hydroxycycloart-23-en-3-one (7) and cycloartenone (9), were isolated and identified by extensive NMR spectroscopy. For cycloartenone (9), full NMR assignments are given as these data were not available in the literature. Eight compounds possess a C(3)=O group, two are 3,4-secocycloartanes bearing a free C(3)OOH group; in one of the cycloartanes, gummiferartane-9 (10), ring A occurs as a seven-membered lactone. PMID:24078595

  14. Shear rheology and filament stretching behaviour of xanthan gum and carboxymethyl cellulose solution in presence of saliva.

    PubMed

    Choi, Hyejung; Mitchell, John R; Gaddipati, Sanyasi R; Hill, Sandra E; Wolf, Bettina

    2014-10-01

    The objective of the work reported in this paper is to determine if saliva addition has an effect on the rheology of xanthan gum solutions. The reasons for the interest was that it has been previously reported that flavour release from high viscosity xanthan thickened foods is not reduced in the same way as foods thickened by other hydrocolloids at comparable viscosities. It was previously postulated that this could be due to an interaction between saliva and xanthan that could change the microstructure and rheology of xanthan solutions. In this work the effect of saliva on the rheology of CMC and xanthan solutions was compared. Solutions of molecularly dissolved xanthan gum and CMC mixed with water or human whole saliva at a ratio of 5:1 showed little impact of the presence of saliva on steady shear or dynamic viscosity for the two hydrocolloids. In filament thinning experiments saliva addition significantly increased filament break-up time for xanthan gum while it had little effect on the break-up time of the CMC filament. Also, filament thinning appeared a lot less even and was not as reproducible in the case of xanthan gum. Addition of CMC and hydroxypropyl methylcellulose (HPMC) to xanthan gum solutions showed a similar increase in break-up time to saliva, but to see this effect the viscosity of the added CMC or HPMC solution had to be very much higher than the viscosity of saliva. The results are discussed in the context of the structure of xanthan gum and the reported extensional rheology of saliva. PMID:25284950

  15. Shear rheology and filament stretching behaviour of xanthan gum and carboxymethyl cellulose solution in presence of saliva

    PubMed Central

    Choi, Hyejung; Mitchell, John R.; Gaddipati, Sanyasi R.; Hill, Sandra E.; Wolf, Bettina

    2014-01-01

    The objective of the work reported in this paper is to determine if saliva addition has an effect on the rheology of xanthan gum solutions. The reasons for the interest was that it has been previously reported that flavour release from high viscosity xanthan thickened foods is not reduced in the same way as foods thickened by other hydrocolloids at comparable viscosities. It was previously postulated that this could be due to an interaction between saliva and xanthan that could change the microstructure and rheology of xanthan solutions. In this work the effect of saliva on the rheology of CMC and xanthan solutions was compared. Solutions of molecularly dissolved xanthan gum and CMC mixed with water or human whole saliva at a ratio of 5:1 showed little impact of the presence of saliva on steady shear or dynamic viscosity for the two hydrocolloids. In filament thinning experiments saliva addition significantly increased filament break-up time for xanthan gum while it had little effect on the break-up time of the CMC filament. Also, filament thinning appeared a lot less even and was not as reproducible in the case of xanthan gum. Addition of CMC and hydroxypropyl methylcellulose (HPMC) to xanthan gum solutions showed a similar increase in break-up time to saliva, but to see this effect the viscosity of the added CMC or HPMC solution had to be very much higher than the viscosity of saliva. The results are discussed in the context of the structure of xanthan gum and the reported extensional rheology of saliva. PMID:25284950

  16. Effect of compression pressure, preservative, and storage with potassium chloride on the microbiological quality of tablets formulated with Terminalia randii Gum (Combretaceae).

    PubMed

    Oluremi, Bolaji Bosede; Bamiro, Oluyemisi Adebowale; Idowu, Abel Olusola; Oduneye, Olayinka Annegret

    2012-10-01

    Gums are used as binders in tablets and also as emulsion stabilisers, suspending agents and thickeners in syrups. The need for other natural gums apart from the conventional gums to be employed as binding agents in tablets formulation led to this study. A gum obtained from the incised trunk of Terminalia randii (Combretaceae) was evaluated for the effect of compression pressure, methyl paraben preservative and storage with potassium chloride, on the microbial load of tablets formulated with the gum. The microbial load was determined by surface spread method on the processed gum at suitable dilutions, and tablets formulated from the gum at different compression pressures. The formulated tablets were evaluated for microbial load, also when stored in potassium chloride for 8 and 12 weeks with and without preservation with 1% Methyl Paraben. In each case the compressed tablets were incubated in 0.1% peptone water as control. The microbial load recorded reflected generally, reduction in microbial counts in tablets formulated with the gum as a binder both in terms of compression at different pressures and when the different compression pressures were associated with or without 1% methyl paraben in the presence of potassium chloride. Comparatively, the processed gum showed higher microbial load than the pressure compressed tablets. Besides the different compression pressures, duration of storage was also found to cause reduction of microbial load, particularly in the formulated tablets compressed with methyl paraben stored in potassium chloride such that after 8 weeks, the microbial load was zero. The studies showed that compression pressures and duration of storage caused marked reduction in microbial load of the tablets formulated with the processed gum of Terminalia randii as a binder. PMID:23009993

  17. Mapping brain region activity during chewing: a functional magnetic resonance imaging study.

    PubMed

    Onozuka, M; Fujita, M; Watanabe, K; Hirano, Y; Niwa, M; Nishiyama, K; Saito, S

    2002-11-01

    Mastication has been suggested to increase neuronal activities in various regions of the human brain. However, because of technical difficulties, the fine anatomical and physiological regions linked to mastication have not been fully elucidated. Using functional magnetic resonance imaging during cycles of rhythmic gum-chewing and no chewing, we therefore examined the interaction between chewing and brain regional activity in 17 subjects (aged 20-31 years). In all subjects, chewing resulted in a bilateral increase in blood oxygenation level-dependent (BOLD) signals in the sensorimotor cortex, supplementary motor area, insula, thalamus, and cerebellum. In addition, in the first three regions, chewing of moderately hard gum produced stronger BOLD signals than the chewing of hard gum. However, the signal was higher in the cerebellum and not significant in the thalamus, respectively. These results suggest that chewing causes regional increases in brain neuronal activities which are related to biting force. PMID:12407087

  18. Evaluation of the toxicity of mastic gum with 13 weeks dietary administration to F344 rats.

    PubMed

    Kang, Jin Seok; Wanibuchi, Hideki; Salim, Elsayed I; Kinoshita, Anna; Fukushima, Shoji

    2007-03-01

    Dietary toxicity of mastic gum, a natural food additive, was studied in male and female F344 rats fed 0%, 0.22%, 0.67% and 2% levels mixed into powdered basal diet for 13 weeks. No mortality or obvious clinical signs were observed in any of the animals throughout the experimental period. Body weights were significantly reduced in the high dose-treated group from week 2 to the end of the experiment in males, and at weeks 8 and 13 in females. There were increased absolute and relative liver weights in a dose-related manner or limited to the high dose group males or females, along with changes in hematological parameters, including increased WBC and platelet in high dose males. Altered serum biochemistry parameters included increases of total proteins, albumin, and total cholesterol in both sexes, and gamma-GTP in females only. However, macroscopic examination at necropsy revealed no gross lesions, and microscopic examination also revealed no treatment-related findings in any organs examined. As dietary treatment of mastic gum for 13 weeks in the present study caused decreased body weights at the high dose, especially in males, and increased liver weights in a dose-related manner in both genders without any morphological findings, it is concluded that the administration of it has a no observed adverse effect level (NOAEL) of 0.67% in the diet. PMID:17092621

  19. The behavior of Carob Gum in the Gastrointestinal Tract of man

    Microsoft Academic Search

    Arthur Andrews Holbrook

    1951-01-01

    Summary  \\u000a \\u000a \\u000a \\u000a 1. \\u000a \\u000a The physical properties of carob seed gum are discussed.\\u000a \\u000a \\u000a \\u000a \\u000a 2. \\u000a \\u000a A study of the behavior of this gum in the gastrointestinal tracts of human beings is described.\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a \\u000a \\u000a a) \\u000a \\u000a Twelve attempts were made by x-ray to demonstrate increased colonic contents 12 hours after volunteers took 2 heaping teaspoonfuls\\u000a of “Vacuosa” orally.\\u000a \\u000a \\u000a \\u000a \\u000a b) \\u000a \\u000a The progress of “Vacuosa”-barium Pelloids ingested by

  20. The Yariv reagent: behaviour in different solvents and interaction with a gum arabic arabinogalactan-protein.

    PubMed

    Paulsen, B S; Craik, D J; Dunstan, D E; Stone, B A; Bacic, A

    2014-06-15

    The ?-D-Glc Yariv reagent is frequently used to isolate and to study the structure of arabinogalactan-proteins with the arabinogalactan type II structure. The present paper describes the aggregation features of the Yariv reagent in water, salt solutions and in organic solvents as determined by NMR, absorption spectroscopy and light scattering experiments. The results indicate that in water the Yariv reagent forms aggregates of up to 300 units and in 1% aqueous NaCl the degree of aggregation is approx. 150. The aggregates are formed both by H-bonds and hydrophobic interactions, the former appearing to be of most importance in water. The interaction between the Yariv reagent and an AGP fraction from gum arabic, showed a degree of aggregation of the Yariv reagent when using 1% NaCl to be of approx. 150 units, whereas disruption of the aggregate took place in 10% NaCl with an aggregation number of approx. 100. Partial acid hydrolysis of an AGP from gum Arabic (Acacia Senegal) and analyses of the linkage types remaining indicated that a certain length of (1?3)-?-linked galactose units was necessary for binding between the Yariv reagent and the AGP. This is in accordance to what also was recently observed by Kitazawa et al. (2013). PMID:24721102

  1. Preparation and characterisation of gelatin-gum arabic aldehyde nanogels via inverse miniemulsion technique.

    PubMed

    Sarika, P R; James, Nirmala Rachel

    2015-05-01

    Gelatin-gum arabic aldehyde nanogels designed by a nanoreactor concept using inverse miniemulsion technique were reported. Stable separate miniemulsions were prepared from gelatin (Gel) and gum arabic aldehyde (GAA). These emulsions were intermixed under sonication to obtain cross-linked nanogels. During fusion, cross-linking occurred between aldehyde groups of GAA and amino groups of gelatin. The concentration of the surfactant and weight fraction of water in the inverse miniemulsion was optimised so as to yield nanogels with controlled particle size. Properties of the nanogels were studied by FT-IR spectroscopy, particle size analysis and XRD. Surface morphology of the nanogels was established by Scanning Electron Microscopy (SEM). SEM and particle size analysis confirmed that nanogels possess spherical morphology with an average diameter of 151±6nm. Hemolysis property of the nanogels was examined and the results indicated that the nanogels were hemocompatible. The in vitro cytotoxicity of the nanogels towards MCF-7 cells was evaluated by MTT assay and the nanogels showed nontoxic behaviour towards the cells. All these studies confirm that these nanogels are potential candidates in applications such as drug and gene delivery. PMID:25748843

  2. Simultaneous determination of five aluminum lake dyes in chewing gum by HPLC with photodiode array detection.

    PubMed

    Yang, Yi; Yin, Jie; Shao, Bing

    2011-09-01

    A simple and rapid method has been developed and validated for the determination of five food aluminum lake dyes (Tartrazine Al lake, Sunset Yellow Al lake, Ponceau 4R Al lake, Allura Red Al lake and Brilliant Blue Al lake) in chewing gum. The dye portions of the target aluminum lakes were simultaneous extracted with 0.25 M NaOH and cleaned up by liquid-liquid extraction with dichloromethane, followed by further purification using Oasis WAX solid-phase extraction (SPE) cartridges. Analytes were separated by HPLC using an Inertsil ® ODS-3 column coupled to a photodiode array detector. The amounts of the aluminum lake dyes were finally quantified and indicated as their dye portions using corresponding calibration curves over ranges of 0.5 to 50 µg ml(-1), with correlation coefficients >0.9999. Recoveries of the dye parts in aluminum lake dyes (spiked at levels of 1, 5, 25 µg g(-1)) ranged from 72.5 to 116.4%, with relative standard deviations between 0.9 and 6.5%. Limits of detection and limits of quantification for all analytes were 0.15 and 0.50 µg g(-1), respectively. This method was successfully applied in real samples of chewing gum. PMID:21707267

  3. GumPack: a personal health assistant with reconfigurable surface components.

    PubMed

    Li, Kejia; Warren, Steve

    2013-01-01

    Wearable and everyday-carry medical devices can improve quality of life for individuals that need frequent health monitoring. Such tools can supplement ubiquitous home care environments populated with medical sensors, extending the reach of these environments and increasing the freedom of their occupants. This paper presents the concept design for an everyday-carry medical device called a 'GumPack': a small cuboid-shaped device that offers wireless connectivity and plug-and-play surface components, where a component can be a biomedical sensor or a wireless network coordinator that manages a body area network. This geometrical layout optimizes access to surface-based medical hardware mounted on a small form factor. The device offers substantive computing power, supports local component reconfigurability, and promotes interoperability with medical device coordination environments. The GumPack is envisioned to be a personal health assistant carried in a pocket or handbag that can operate alone or interface to, e.g., a cell phone. PMID:23502254

  4. Release of indomethacin from bioadhesive tablets containing carbopol 941 modified with Abelmuschus esculentus (okra) gum.

    PubMed

    Attama, A A; Adikwu, M U; Amorha, C J

    2003-09-01

    Carbopol 941 (C-941) and Abelmuschus esculentus gum (Okra gum, AEG) were used as bioadhesive polymers in the formulation of mucoadhesive indomethacin tablets. Different batches of the tablet compacts were formulated based on different combination ratios of the polymers. The bioadhesive properties of the tablets were studied using a tensiometer: Tablets coated with 50% w/v solution of Eudragit I. 100 in ethanol, were also prepared and evaluated. The following tablet physical properties were evaluated: hardness, uniformity of weight, disintegration time, friability, and absolute drug content. Release studies were determined in simulated intestinal fluid (SIF pH 7.2) without pancreatin, and in 0.1 N solution of HCl. Result obtained indicated that tablets with equal ratio of C-941 and AEG (1:1) gave the highest bioadhesive strength for both the coated and uncoated tablets. The percentage of drug released ranged from 53-90% for uncoated tablets in 0.1 N HCl and SIF, and 9-16% for coated tablets in 0.1 N HCl, and 63-100% for coated tablets in SIF after 8 hrs. PMID:14677275

  5. Potentiality of the "Gum Metal" titanium-based alloy for biomedical applications.

    PubMed

    Gordin, D M; Ion, R; Vasilescu, C; Drob, S I; Cimpean, A; Gloriant, T

    2014-11-01

    In this study, the "Gum Metal" titanium-based alloy (Ti-23Nb-0.7Ta-2Zr-1.2O) was synthesized by melting and then characterized in order to evaluate its potential for biomedical applications. Thus, the mechanical properties, the corrosion resistance in simulated body fluid and the in vitro cell response were investigated. It was shown that this alloy presents a very high strength, a low Young's modulus and a high recoverable strain by comparison with the titanium alloys currently used in medicine. On the other hand, all electrochemical and corrosion parameters exhibited more favorable values showing a nobler behavior and negligible toxicity in comparison with the commercially pure Ti taken as reference. Furthermore, the biocompatibility tests showed that this alloy induced an excellent response of MC3T3-E1 pre-osteoblasts in terms of attachment, spreading, viability, proliferation and differentiation. Consequently, the "Gum Metal" titanium-based alloy processes useful characteristics for the manufacturing of highly biocompatible medical devices. PMID:25280716

  6. Interactions between fluorinated cationic guar gum and surfactants in the dilute and semi-dilute solutions.

    PubMed

    Wang, Chen; Li, Xiaorui; Li, Peizhi; Niu, Yuhua

    2014-01-01

    The interactions between the fluorinated cationic guar gum (FCGG) and ionic surfactants including cetyl trimethyl ammonium bromide (CTAB) and sodium lauryl sulfate (SDS) were studied by light scattering, fluorescence spectroscopy, UV-spectrophotometer, (19)F NMR and dynamic rheometer, respectively. The FCGG is prepared with cationic guar gum, isophorone diisocyanate and 2,2,3,4,4,4-hexafluoro-1-butanol. The results show that, with the addition of the surfactants, the stretching degree of the FCGG chains is increased in the FCGG/CTAB solutions, while the dramatical shrinking of FCGG chain, the phase separation and the re-stretched macromolecules appear successively because of the electricity neutralization reaction in the FCGG/SDS system. The mixed hydrophobic domains in all solutions will be reinforced and then dismantled. The solution elasticity shows up the maximum value accordingly. The surfactants can be embedded in the micro-domains and then hinder the fluorinated segmental motions. The interactions between FCGG and SDS are much stronger than those between FCGG and CTAB. PMID:24274554

  7. Ultrasound-assisted formation of the canthaxanthin emulsions stabilized by arabic and xanthan gums.

    PubMed

    Gharibzahedi, Seyed Mohammad Taghi; Razavi, Seyed Hadi; Mousavi, Seyed Mohammad

    2013-07-01

    There is interest in incorporating canthaxanthin (CTX) into food emulsions due to its high potential health benefits. The used CTX in this study was produced by the bacterium of Dietzia natronolimnaea HS-1. Then, the influence of main emulsion components (gum arabic (GA), xanthan gum (XG) and coconut oil (CO)) on the surface-weighted mean diameter (D32), polydispersity index (PDI), specific surface area (SSA) of droplets and density of the emulsions containing CTX was optimized using response surface methodology (RSM). Polynomial equations between the responses and independent variables were derived. The linear effect of GA had a significant (p<0.0001) term in all reduced models. The optimal formulation for emulsions was composed of GA content of 9.85% (w/w), XG content of 0.13% (w/w) and CO concentration of 3.50% (w/w). This optimum formulation yielded D32 of 0.752 ?m, PDI of 1.533, SSA of 9.995 m(2)/ml and density of 1.0357 g/cm(3). PMID:23688450

  8. Exercise as an adjunct to nicotine gum in treating tobacco dependence among women

    PubMed Central

    Kinnunen, Taru; Leeman, Robert F.; Korhonen, Tellervo; Terwal, Donna M.; Garvey, Arthur J.; Quiles, Zandra N.; Hartley, L. Howard

    2013-01-01

    This was the first randomized, controlled smoking cessation trial assessing the efficacy of an exercise intervention as an adjunct to nicotine gum therapy in comparison to both equal contact control and standard care control conditions. Sedentary female smokers aged 18-55 were provided with nicotine gum treatment along with brief behavioral counseling and were randomized into one of these three behavioral adjunct conditions. In the “intent-to-treat” sample (N=182), at end of treatment and at one-year follow up, there were clear, but non-significant, trends in univariate analyses in which the exercise and equal contact control conditions both had higher rates of abstinence than the standard care control. However, when adjusting for other predictors of relapse in a multiple logistic regression, both exercise and equal contact control showed an advantage over standard care control in avoiding early relapse (i.e., after 1 week). In a multivariate survival model adjusting for other predictors, the equal contact condition had a significantly lower likelihood of relapse compared to the standard care condition and there was a near significant trend in which exercise offered an advantage over standard care as well. While these findings suggest a slightly improved likelihood of abstinence with exercise compared with standard care, exercise did not differ from equal contact control in its efficacy. Potential explanations for these equivalent levels of efficacy and implications for the findings are discussed. PMID:18418791

  9. New intrinsic mechanism on gum-like superelasticity of multifunctional alloys

    PubMed Central

    Liu, Jia-Peng; Wang, Yan-Dong; Hao, Yu-Lin; Wang, Yunzhi; Nie, Zhi-Hua; Wang, Dong; Ren, Yang; Lu, Zhao-Ping; Wang, Jinguo; Wang, Haoliang; Hui, Xidong; Lu, Ning; Kim, Moon J.; Yang, Rui

    2013-01-01

    Ti-Nb-based Gum Metals exhibit extraordinary superelasticity with ultralow elastic modulus, superior strength and ductility, and a peculiar dislocation-free deformation behavior, most of which challenge existing theories of crystal strength. Additionally, this kind of alloys actually displays even more anomalous mechanical properties, such as the non-linear superelastic behavior, accompanied by a pronounced tension-to-compression asymmetry, and large ductility with a low Poisson's ratio. Two main contradictory arguments exist concerning the deformation mechanisms of those alloys, i.e., formation of reversible nanodisturbance and reversible martensitic transformation. Herein we used the in-situ synchrotron high-energy X-ray scattering technique to reveal the novel intrinsic physical origin of all anomalous mechanical properties of the Ti-24Nb-4Zr-8Sn-0.10O alloy, a typical gum-like metal. Our experiments provide direct evidence on two different kinds of interesting, stress-induced, reversible nanoscale martensitic transitions, i.e., the austenitic regions with B2 structure transform to ?? martensite and those with BCC structure transform to ? martensite. PMID:23831664

  10. Rheological behavior of xanthan gum solution related to shear thinning fluid delivery for subsurface remediation.

    PubMed

    Zhong, L; Oostrom, M; Truex, M J; Vermeul, V R; Szecsody, J E

    2013-01-15

    Xanthan gum solutions are shear thinning fluids which can be used as delivery media to improve the distribution of remedial amendments injected into heterogeneous subsurface environments. The rheological behavior of the shear thinning solution needs to be known to develop an appropriate design for field injection. In this study, the rheological properties of xanthan gum solutions were obtained under various chemical and environmental conditions relevant to delivery of remedial amendments to groundwater. Higher xanthan concentration raised the absolute solution viscosity and increased the degree of shear thinning. Addition of remedial amendments (e.g., phosphate, sodium lactate, ethyl lactate) caused the dynamic viscosity of xanthan solutions to decrease, but they maintained shear-thinning properties. Use of mono- and divalent salts (e.g., Na(+), Ca(2+)) to increase the solution ionic strength also decreased the dynamic viscosity of xanthan and the degree of shear thinning, although the effect reversed at high xanthan concentrations. A power law analysis showed that the consistency index is a linear function of the xanthan concentration. The degree of shear thinning, however, is best described using a logarithmic function. Mechanisms to describe the observed empiricism have been discussed. In the absence of sediments, xanthan solutions maintained their viscosity for months. However, the solutions lost their viscosity over a period of days to weeks when in contact with site sediment. Loss of viscosity is attributed to physical and biodegradation processes. PMID:23246952

  11. Draft Genome Sequences of Four Bacillus thermoamylovorans Strains Isolated from Milk and Acacia Gum, a Food Ingredient

    PubMed Central

    Krawczyk, Antonina O.; Berendsen, Erwin M.; Eijlander, Robyn T.; de Jong, Anne; Wells-Bennik, Marjon H. J.

    2015-01-01

    The thermophilic bacterium Bacillus thermoamylovorans produces highly heat-resistant spores that can contaminate food products, leading to their spoilage. Here, we present the whole-genome sequences of four B. thermoamylovorans strains, isolated from milk and acacia gum. PMID:25814599

  12. A comparison of the rheological behaviour of crude and refined locust bean gum preparations during thermal processing

    Microsoft Academic Search

    M. Samil Kök; SandraE Hill; JohnR Mitchell

    1999-01-01

    The behaviour, during thermal processing, of a higher quality analytical-grade (AG) locust bean gum (LBG) was compared with a lower quality technical grade (TG) LBG. The TG material contained a substantial amount of material (40%) of dry weight, which remained insoluble after heating to 70°C. Sugar analysis suggests that this insoluble material contained high levels of arabinose. The TG material

  13. Effect of mastication, antioxidants and crosslink density on the mechanical properties of gum and black-filled natural rubber vulcanizates

    Microsoft Academic Search

    Nittaya Rattanasom

    1999-01-01

    The tensile behavior of black-filled natural rubber (NR) vulcanizates, as well as a corresponding gum compositions were studied. The effect of mastication, antioxidants and crosslink density on tensile strength and cut growth were determined. Dumbbells, with and without edge cuts, were strained continuously to rupture. Crack growth was determined at various strains. Catastrophic rupture paths and micro-cracking patterns were examined

  14. Barium Ions Crosslinked Alginate and Sterculia Gum-Based Gastroretentive Floating Drug Delivery System for Use in Peptic Ulcers

    Microsoft Academic Search

    Baljit Singh; Dimpal Chauhan

    2011-01-01

    The gastro-retentive drug delivery system is required to improve the bioavailability and therapeutic efficacy of the drugs used for the diseases associated with the stomach. Both sterculia gum and alginate enhance the repair of mucosal damage in the GI tract and pantoprazole is a therapeutic agent for GI tract ulcers. Ionotropic gelation of these polysaccharides for the release of pantoprazole

  15. Rate and yield relationships in the production of xanthan gum by batch fermentations using complex and chemically defined growth media

    Microsoft Academic Search

    Anthony Pinches; Leslie J. Pallent

    1986-01-01

    Rate and yield information relating to biomass and product formation and to nitrogen, glucose and oxygen consumption are described for xanthan gum batch fermentations in which both chemically defined (glutamate nitrogen) and complex (peptone nitrogen) media are employed. Simple growth and product models are used for data interpretation. For both nitrogen sources, rate and yield parameter estimates are shown to

  16. Influence of xanthan gum on the formation and stability of sodium caseinate oil-in-water emulsions

    Microsoft Academic Search

    Y. Hemar; M. Tamehana; P. A. Munro; H. Singh

    2001-01-01

    Studies have been made of the changes in droplet sizes, surface coverage and creaming stability of emulsions formed with 30% (w\\/w) soya oil, and aqueous solution containing 1 or 3% (w\\/w) sodium caseinate and varying concentrations of xanthan gum. Addition of xanthan prior to homogenization had no significant effect on average emulsion droplet size and surface protein concentration in all

  17. Effect of emulsifier and guar gum on micro structural, rheological and baking performance of frozen bread dough

    Microsoft Academic Search

    P. D. Ribotta; G. T. Pérez; A. E. León; M. C. Añón

    2004-01-01

    The influence of mono- and diacylglycerols esterified to mono- and diacetyltartaric acid (DATEM) and guar gum on dynamic rheological behaviour, starch gelatinization, microstructure and bread properties of frozen dough were analysed. The results obtained showed that the dough freezing and storage at ?18 °C decreased the bread quality. The dough freezing and frozen storage provoked a decrease in the complex

  18. The biology of Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae), a parasitoid of the red gum lerp psyllid (Hemiptera: Psylloidea)

    Microsoft Academic Search

    Kent M. Daane; Karen R. Sime; Donald L. Dahlsten; John W. Andrews Jr.; Robert L. Zuparko

    2005-01-01

    The red gum lerp psyllid, Glycaspis brimblecombei Moore (Hemiptera: Psylloidea), is native to Australia, where it feeds upon Eucalyptus species. It first appeared near Los Angeles, California, in 1998, and soon spread throughout the state. A biological control program directed against the psyllid was initiated and Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) was imported from Australia and released in California. During

  19. Effective remediation of phenol,2,4-bis(1,1-dimethylethyl) and bis(2-ethylhexyl) phthalate in farm effluent using Guar gum - A plant based biopolymer.

    PubMed

    Kee, Yang Ling; Mukherjee, Sumona; Pariatamby, Agamuthu

    2015-10-01

    This study was carried out to evaluate the efficiency of Guar gum in removing Persistent Organic Pollutants (POPs), viz. phenol,2,4-bis(1,1-dimethylethyl) and bis(2-ethylhexyl) phthalate (DEHP), from farm effluent. The removal efficiency was compared with alum. The results indicated that 4.0mgL(-1) of Guar gum at pH 7 could remove 99.70% and 99.99% of phenol,2,4-bis(1,1-dimethylethyl) and DEHP, respectively. Box Behnken design was used for optimization of the operating parameters for optimal POPs removal. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopy studies were conducted on the flocs. SEM micrographs showed numerous void spaces in the flocs produced by Guar gum as opposed to those produced by alum. This indicated why Guar gum was more effective in capturing and removal of suspended particles and POPs as compared to alum. FTIR spectra indicated a shift in the bonding of functional groups in the flocs produced by Guar gum as compared to raw Guar gum powder signifying chemical attachment of the organics present in the effluent to the coagulant resulting in their removal. Guar gum is highly recommended as a substitute to chemical coagulant in treating POPs due to its non-toxic and biodegradable characteristics. PMID:25966329

  20. The effects of chewing-gum stick size and duration of chewing on salivary flow rate and sucrose and bicarbonate concentrations.

    PubMed

    Rosenhek, M; Macpherson, L M; Dawes, C

    1993-10-01

    The objectives were to determine (1) the relations between salivary flow rate and the sample weights of chewing-gum and gum base, (2) whether any reduction in salivary flow rate with duration of chewing is due to a reduction in hardness of gum base with chewing, and (3) the sucrose and bicarbonate concentrations in saliva elicited by different weights of chewing-gum containing sucrose. Ten subjects chewed, for 20 min, samples of 1, 2, 3, 6 and 9 g of gum base and of a sucrose-containing chewing-gum. With each sample, salivary flow rates peaked initially and then fell to a relatively constant value. Flow rates during the periods of 1-2 and 15-20 min were linearly related to the logarithm of sample weight. With the chewing-gum samples, virtually all the sucrose was released into the saliva during the 20 min of chewing, with peak concentrations (201-666 mM) at 1-2 min, and bicarbonate concentrations were higher with the 9-g than the 3-g samples. Six subjects chewed 3 g of gum base and within 45 min the weight of base had increased to 122% of the original, presumably due to the uptake of saliva. The hardness of gum base was determined at 21 and 36 degrees C, 21 and 36 degrees C after it had been chewed, and 21 degrees C after it had been chewed without exposure to saliva, and gave Brinell values of 0.277, 0.038, 0.022, 0.002 and 0.061, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8279993

  1. Bleeding gums

    MedlinePLUS

    ... and ask questions about the problem and your oral care habits. You may also be asked questions about your diet and the medicines you take. Diagnostic tests that may be ... as a CBC or blood differential X-rays of the teeth and jawbone

  2. Bleeding Gums

    MedlinePLUS

    ... should not be used as a substitute for evaluation and treatment by a physician. Please review our terms of use . Home Symptom Checkup Injury Checkup Disease Checkup Women's Checkup Pregnancy Checkup Baby Checkup Mens Checkup Stephen J. Schueler, M.D. About Stephen ...

  3. Release properties of chemical and enzymatic crosslinked gelatin-gum Arabic microparticles containing a fluorescent probe plus vetiver essential oil.

    PubMed

    Prata, Ana S; Zanin, Maria H A; Ré, Maria I; Grosso, Carlos R F

    2008-12-01

    Oil-containing gelatin-gum Arabic microparticles were prepared by complex coacervation followed by crosslinking with glutaraldehyde or transglutaminase. A fluorescent mixture, khusimyl dansylate (KD) as the fluorescent compound mixed to the vetiver essential oil, was used as oil model. The effect of the type of crosslinking of the coacervated gelatin-gum Arabic membrane, the physical state of microparticles, wet or freeze-dried and the type of release media, aqueous with surfactants, Sodium Dodecyl Sulphate (sds) or Tween 80 (tw) and anhydrous ethanol as organic media on the release rate of the KD from the microparticles, was experimentally investigated. It was shown that the oil was dispersed uniformly throughout the microparticles and the chemical crosslinked microparticles were more resistant to swelling, presenting smaller sizes after hydration. Also the crosslinking effect, transglutaminase or glutaraldehyde, could be confirmed by the integrity of the crosslinked gelatin-gum Arabic microparticles after incubation in the aqueous sds media, compared to complete dissolution of the uncrosslinked microparticles in this media. The cumulative fluorescent KD release from the gelatin-gum Arabic microparticles decreased in the following order of dissolution media: anhydrous ethanol>tw>sds and the wet microparticles have shown a faster KD release than freeze-dried ones. A mathematical model was used to estimate the diffusion coefficient (D). The chemically crosslinked gelatin-gum Arabic microparticles ensured a pronounced retard effect in the KD diffusion, presenting a D varying from 0.02 to 0.6 x 10(-11)cm(2)/s, mainly in an aqueous media, against D varying from 1.05 to 13.9 x 10(-11)cm(2)/s from the enzymatic crosslinked microparticles. PMID:18835139

  4. The influence of metabolic network structures and energy requirements on xanthan gum yields.

    PubMed

    Letisse, Fabien; Chevallereau, Paule; Simon, Jean-Luc; Lindley, Nic

    2002-11-13

    The metabolic network of Xanthomonas campestris is complex since a number of cyclic pathways are present making simple stoichiometric yield predictions difficult. The influence of certain pathway configurations and the resulting variations in flux have been examined as regards the maximum yield potential of this bacteria for xanthan gum production. These predictions have been compared with experimental results showing that the strain employed is functioning close to its theoretical maximum as regards yield criteria. The major constraint imposed on the network concerns energy availability which has a more pronounced effect on yield than carbon precursor supply. This can be attributed to the relatively high maintenance requirements determined experimentally and incorporated into the model. While some of this overall energy burden will undoubtedly be associated with incompressible metabolic requirements such as sugar uptake and xanthan efflux mechanisms, future strain improvement strategies will need to attack other non-essential energy-consuming reactions, if yields are to be further increased. PMID:12385717

  5. Xylitol chewing gum in caries prevention: a field study in children.

    PubMed

    Isokangas, P; Alanen, P; Tiekso, J; Makinen, K K

    1988-08-01

    As the prevalence of dental caries decreases in industrialized nations like the United States, it simultaneously increases in developing nations and Third World countries. The decrease in the West is attributed to increased use of fluorides, but the increase in developing countries has been explained by an increase in the consumption of sugar. As this information continues to propel researchers to find sucrose substitutes, xylitol has been singled out as a proposed sucrose replacement. The question tackled by this study was: Can the daily use of chewing gum containing xylitol increase the efficacy of the existing caries-preventive measures now regularly used for 11- to 15-year-old children in most industrialized western countries? PMID:3166474

  6. Effect of okra gum on the pasting, thermal, and viscous properties of rice and sorghum starches.

    PubMed

    Alamri, Mohammed S; Mohamed, Abdellatif A; Hussain, Shahzad

    2012-06-01

    The effect of okra gum (OE) on the physical properties of rice and sorghum starches was investigated using rapid visco-analyzer (RVA), Brookfield viscometer, differential scanning Calorimetry (DSC), and light microscopy. Starch was replaced with 5, 10, 15% OE weight basis (g/100 g). In the presence of OE, the peak and final viscosity as well as the setback of both starches were reduced. However, the difference between the theoretical and the measured setback was more than just can be attributed to the omitted starch. The DSC data of the blends showed higher peak temperature compared to the control, indicating slower starch gelatinization in the presence of OE. Brookfield profiles demonstrated increase in shear stress at higher shear rate confirming pseudoplasticity of the system (n<1). Over all, it can be assumed that OE has influenced the properties of the starches, particularly, by decreasing viscosity, setback, and pseudoplasticity of the starch gels. PMID:24750624

  7. Molecular gas in cometary globules: CG4 and CG 6 in the GUM Nebula.

    NASA Astrophysics Data System (ADS)

    Gonzalez-Alfonso, E.; Cernicharo, J.; Radford, S. J. E.

    1995-01-01

    With the SEST telescope, we observed ^12^CO(10,->^13^)CO(10,->and) C^18^O(10)->emission from the cometary globules CG4 and CG6 in the Gum Nebula and also CS(21->and) HCO^+^(10->in) CG4. There are =~50Msun_ and =~5.5Msun_ of molecular hydrogen, respectively, in CG4 and CG6. The gas kinetic temperature is =~16K in both globules. The gas kinematics indicate the globules are strongly affected by ionization fronts on their surfaces. Red and blue line wings are found throughout CG4 and the velocity gradients suggest a divergent flow that may be responsible for the apparent disruption of the globule's head. In CG6, a head to tail velocity gradient indicates a dynamical age of 10^6^yr. We discuss a possible evolution scenario for these globules.

  8. Method of inhibiting crosslinking of aqueous xanthan gums in the presence of ferric acid ions

    SciTech Connect

    Crowe, C.W.

    1982-03-02

    The cross linking of aqueous xanthan gums in the presence of ferric ions is inhibited or prevented by adding a soluble alkanoic and/or alkenoic acid having at least 4 carbon atoms and bearing at least 2 hydroxyl groups per molecule, and/or a soluble salt of ..gamma..-lactone. This combination of ingredients forms gelled acid compositions which are useful in acidizing treatments of wells. The gelled acid compositions are viscous fluids which have increased stability against shear and thermal degradation and other properties which result in retarded reaction rates and reduced fluid leak-off during acidizing treatments of subterranean formations surrounding well bores. The aqueous gelled acids have the further advantage of inhibiting or preventing the formation of insoluble compounds, such as ferric hydroxide, during such acidizing treatments. 13 claims.

  9. Mineralization of hydroxyapatite upon a unique xanthan gum hydrogel by an alternate soaking process.

    PubMed

    Izawa, Hironori; Nishino, Shoji; Maeda, Hiroyuki; Morita, Kohei; Ifuku, Shinsuke; Morimoto, Minoru; Saimoto, Hiroyuki; Kadokawa, Jun-ichi

    2014-02-15

    We previously reported a xanthan gum (Xan) hydrogel showing excellent mechanical properties. Mineralization of hydroxyapatite (Hap) upon the Xan hydrogel would provide a unique biomaterial applicable for bone tissue engineering. Here, we show the mineralization of Hap upon the Xan hydrogel by means of an alternate soaking process. Hap was gradually grown upon the Xan-matrix surface with increasing number of soaking cycles due to the ionic interactions between calcium cations and carboxyl groups. Interestingly, the mineralization induced a microstructure change in the gel-matrix from a layered structure to a porous structure. The mechanical properties of the resulting Hap-Xan composite hydrogels were further investigated by a tensile test, where the Hap-Xan composite hydrogel with an appropriate amount of Hap (Xan/Hap=2.7) was capable of approximately 370% elongation. PMID:24507355

  10. Lepidium perfoliatum seed gum: a new source of carbohydrate to make a biodegradable film.

    PubMed

    Seyedi, Samira; Koocheki, Arash; Mohebbi, Mohebbat; Zahedi, Younes

    2014-01-30

    Microstructural, physical, mechanical and thermal properties of a novel biodegradable film based on Lepidium perfoliatum seed gum (LPSG) were investigated. LPSG films were successfully prepared by incorporation of four levels of glycerol (40%, 50%, 60% and 70%, w/w). As expected, increasing glycerol concentration from 40 to 70% (w/w), increased water vapor permeability (WVP), elongation at break (EB%), moisture content, moisture adsorption and water solubility of LPSG films; whilst, elastic modulus (EM), contact angle, melting point (Tm), enthalpy of melting (?Hm) and glass transition point (Tg) decreased significantly. LPSG films became slightly greenish and yellowish in color but still transparent in appearance. The images taken from electron scanning microscopy indicated uniform surface, compact sheets with no holes or fracture. This study demonstrates that LPSG based films with desired properties can be obtained by adjusting glycerol content. PMID:24299783

  11. Guar gum and scleroglucan interactions with borax: experimental and theoretical studies of an unexpected similarity.

    PubMed

    Bocchinfuso, Gianfranco; Mazzuca, Claudia; Sandolo, Chiara; Margheritelli, Silvia; Alhaique, Franco; Coviello, Tommasina; Palleschi, Antonio

    2010-10-21

    Guar gum is a galactomannan that assumes a very flexible conformation in solution, while Scleroglucan is a very rigid polysaccharide that dissolves in water as triple helices. Both polymers can form gels in the presence of borax. Despite their structural differences, the freeze-dried gel systems of both polymers, when compressed to form tablets, show a peculiar anisotropic swelling in water that reflects an amazing similarity in terms of their molecular properies. In this paper the behavior of the Guar/borax gel is compared with that of Scleroglucan/borax. The macroscopic properties of the two systems were characterized in terms of rheological measurements. Atomic force microscopy images and molecular dynamics simulation allowed to evaluate, at molecular level, the effect of borax addition to the Guar polymer. Both experiments show that an increasing of the polymer rigidity is produced by borax. The role played by galactose in the side chain was also discussed. PMID:20863102

  12. In situ generation of silver nanoparticles within crosslinked 3D guar gum networks for catalytic reduction.

    PubMed

    Zheng, Yian; Zhu, Yongfeng; Tian, Guangyan; Wang, Aiqin

    2015-02-01

    The direct use of guar gum (GG) as a green reducing agent for the facile production of highly stable silver nanoparticles (Ag NPs) within this biopolymer and subsequent crosslinking with borax to form crosslinked Ag@GG beads with a 3D-structured network are presented here. These crosslinked Ag@GG beads were characterized using UV-vis absorption spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy, and then tested as a solid-phase heterogenerous catalyst for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of excess borohydride. The results indicate that these crosslinked Ag@GG beads show excellent catalytic performance for the reduction of 4-NP within 20 min and can be readily used for 10 successive cycles. PMID:25445685

  13. Electrospinning of commercial guar-gum: Effects of purification and filtration.

    PubMed

    Lubambo, Adriana F; de Freitas, Rilton A; Sierakowski, Maria-R; Lucyszyn, Neoli; Sassaki, Guilherme L; Serafim, Bruno M; Saul, Cyro Ketzer

    2013-04-01

    Guar gums of two different commercial sources were successfully electrospun on both mica and copper tape at several concentrations starting from 1% (w/w). The electrospun fibers formed with the raw materials were not uniform and presented aggregates and beads within the fibers. Two different purification procedures and a filtration sequence with different pore size membranes were applied to enhance galactomannan solution homogeneity and solubility. The consequence was improved fiber morphology. We observed that the precipitation step, within the purification procedure, produced changes in the molar mass distribution and yielded different fiber diameter. Furthermore, spherical aggregates between fibers and within them disappeared after the sequential filtration. The resulting electrospun fiber diameter decreased with membrane pore diameter reduction. We conclude that the filtration process is responsible for molecular disentanglement, as well as disaggregation, which leads to improved electrospun galactomannan fiber morphology. PMID:23499087

  14. Processing of waxy starch/xanthan gum mixtures within the gelatinization temperature range.

    PubMed

    Heyman, Bart; Depypere, Frédéric; Van der Meeren, Paul; Dewettinck, Koen

    2013-07-25

    Pasting experiments of waxy potato and waxy maize starch systems were set up in which temperatures close to the gelatinization temperature were selected (67.5, 70 and 72.5°C). DSC measurements showed that under these conditions small fractions of the starches remained ungelatinized. During the pasting process two different shear rates were imposed (50s(-1) and 150s(-1)) to investigate the shear stability of the different starch containing systems. Swelling of the granules occurred in a more controlled manner and granule breakdown during pasting could be limited. As a result of these heating conditions more swollen granules are present, as confirmed by laser light diffraction. This positive effect was clearly noticeable in the flow curves of the cooled pastes. Xanthan gum addition could further reduce breakdown either by restricting the swelling or by stabilizing the granules. At higher starch contents the former is most likely dominating. PMID:23768601

  15. Preparation and properties of organic-inorganic composite superabsorbent based on xanthan gum and loess.

    PubMed

    Feng, Enke; Ma, Guofu; Wu, Yajuan; Wang, Haiping; Lei, Ziqiang

    2014-10-13

    A new, low-cost, and eco-friendly organic-inorganic composite superabsorbent was successfully synthesized in aqueous solution by polymerization xanthan gum (XG), neutralized acrylic acid (AA) and loess using ammonium persulfate (APS) as initiator and N,N-methylenebisacrylamide (MBA) as crosslinker. Structure and morphological characterizations of the composite superabsorbent were investigated by Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The loess content, pH values, surfactants, salts and temperature which could affect the swelling and water-retention capabilities of the composite superabsorbent were investigated. The composite superabsorbent exhibits excellent water absorbency (610 g/g in distilled water), pH-stability (pH 5-10), and higher swelling capacity in anionic surfactant solution; on the other hand, the composite superabsorbent can be used for removing multivalent metal ions. PMID:25037376

  16. [Effect of sucrose-containing gum and fluoridated dentifrice on in situ remineralization of artificial caries].

    PubMed

    de Freitas, R R; de Oliveira, J A; Taga, E M; Buzalaf, M A

    2001-01-01

    The aim of this study was to evaluate the remineralization of incipient carious lesions in bovine enamel in situ. Artificial carious lesions were produced and fixed in removable lower appliances in the region of the lingual surfaces of first molars, in six volunteers with ages between 18 and 22 years, who were subjected to 3 distinct experimental periods of 1 week each. In the first period (control group), patients brushed their teeth with a non-fluoridated dentifrice 4 times a day (after meals), and, in the second period (group I), patients used a dentifrice containing 1,500 ppm of fluorine (in the form of MFP). In the third period (group II) volunteers brushed their teeth with non-fluoridated dentifrice and used chewing gum containing 60% of sucrose during 20 minutes, 4 times a day (after meals). Before and after each treatment, the specimens underwent Vicker's hardness test (200 g of load), and the remineralization percentage (alpha) was calculated. The control group showed 2.78% of demineralization, and groups I and II showed 3.36 and 5.21% of remineralization, respectively. Statistical analysis (with Kruskal-Wallis and Miller's tests) showed significant difference (p < 0.05) between the control and experimental groups (I and II). Group II showed greater alpha than group I, but this difference was not significant. These results suggest that the use of sucrose-containing chewing gum and fluoridated dentifrice has a considerable effect on the remineralization of incipient carious lesions and may be a valuable alternative for their prevention. PMID:11705205

  17. Evaluation of Prosopis africana Seed Gum as an Extended Release Polymer for Tablet Formulation.

    PubMed

    Nadaf, Sameer; Nnamani, Petra; Jadhav, Namdeo

    2015-06-01

    In the present work, an attempt has been made to screen Prosopis africana seed gum (PG), anionic polymer for extended release tablet formulation. Different categories of drugs (charge basis) like diclofenac sodium (DS), chlorpheniramine maleate (CPM), and ibuprofen (IB) were compacted with PG and compared with different polymers (charge basis) like xanthan gum (XG), hydroxypropyl methyl cellulose (HPMC-K100M), and chitosan (CP). For each drug, 12 batches of tablets were prepared by wet granulation technique, and granules were evaluated for flow properties, compressibility, and compactibility by Heckel and Leuenberger analysis, swelling index, in vitro dissolution studies, etc. It has been observed that granules of all batches showed acceptable flowability. According to Heckel and Leuenberger analysis, granules of PG-containing compacts showed similar and satisfactory compressibility and compactibility compared to granules of other polymers. PG showed significant swelling (P?

  18. Directly compressible medicated chewing gum formulation for quick relief from common cold

    PubMed Central

    Chaudhary, Shivang A; Shahiwala, Aliasgar F

    2012-01-01

    Introduction: Common cold is the most frequently recurring disease in the world and is a leading cause of doctor visits and missed days from school and work. Cold reliever medicated chewing gum (MCG) will be a definitive patient acceptable solution for this condition. Anti-allergic, cetirizine (CTZ) is a BCS class-I (highly soluble and highly permeable) non-sedating antihistaminic drug and this study was based on the hypothesis that CTZ as a BCS class I drug will be easily released from chewing gum into the salivary fluid within few minutes of chewing and can be easily permeated from oral mucosa by the pressure created by the chewing action and absorbed to a larger extent into the systemic circulation. Therefore, ultimately patients will get quick relief from symptoms of common cold with greater compliance compared to other conventional dosage forms. Materials and Methods: This study mainly focuses on taste masking of CTZ by inclusion complexation method, its formulation development in the MCG form and its quality and performance evaluation with the study of potential factors affecting drug release by 32 full factorial experimental design. A “chew out” study is carried out to assess in vivo drug release from MCG, in which residual amount is extracted from the chewed sample. Results: Formulation ingredients, such as elastomers, softeners, bulking agents, play an important role in the feel of the final product and its consistency; while sweeteners and flavors play a very essential character in its sensory properties. Conclusion: Interindividual variation in chewing frequency and chewing intensity is the main factor which affects release of active ingredient from MCG; while salivary dilution and involuntary swallowing are main reasons for variability in the absorption site, i.e., either from buccal mucosa or from gastrointestinal tract. PMID:23373003

  19. Xanthan gum recovery from fermentation broth using ultrafiltration: Kinetics and process evaluation

    SciTech Connect

    Lo, Y.M.; Yang, S.T.; Min, D.B. [Ohio State Univ., Columbus, OH (United States)

    1995-12-01

    Ultrafiltration of xanthan gum solution as an alternative method to alcohol precipitation for xanthan gum recovery from dilute fermentation broth was studied. A polysulfone membrane (with 500,000 MWCO) hollow fiber (106 mil fiber diameter) tubular cartridge was used to concentrate xanthan broth from less than 3 (w/v) % to {approximately}13.5 (w/v) %, with the xanthan recovery yield of {approximately}95 % or higher. During ultrafiltration, the filtrate flux was one order of magnitude lower for xanthan broth than for water, However, the flux remained almost constant for xanthan concentrations up to {approximately}8%. It was then reduced dramatically as the xanthan concentration increased beyond 8%. The reduced filtrate flux was caused by the reduced pumping (shear) rate and higher viscosities at higher xanthan concentrations. At constant xanthan concentration, the filtrate flux remained almost unchanged for the entire period studied, suggesting that the process is not subject to membrane fouling. In general, the filtrate flux decreased with increasing the xanthan concentration and increased with increasing the pumping (shear) rate and the trans-membrane pressure difference. Changing the solution pH had a slight effect on the viscosity of xanthan solution, but did not affect the filtration performance. Even under high-shear-rate conditions, ultrafiltration did not give any adverse effects on the rheological properties and molecular weight of the xanthan polymer. Thus, ultra filtration can be used to concentrate xanthan broth from fermentation by a factor of four or higher and to reduce the subsequent alcohol recovery costs by at least 75 %.

  20. Xanthan Gum Removal for 1H-NMR Analysis of the Intracellular Metabolome of the Bacteria Xanthomonas axonopodis pv. citri 306

    PubMed Central

    Pegos, Vanessa R.; Canevarolo, Rafael R.; Sampaio, Aline P.; Balan, Andrea; Zeri, Ana C. M.

    2014-01-01

    Xanthomonas is a genus of phytopathogenic bacteria, which produces a slimy, polysaccharide matrix known as xanthan gum, which involves, protects and helps the bacteria during host colonization. Although broadly used as a stabilizer and thickener in the cosmetic and food industries, xanthan gum can be a troubling artifact in molecular investigations due to its rheological properties. In particular, a cross-reaction between reference compounds and the xanthan gum could compromise metabolic quantification by NMR spectroscopy. Aiming at an efficient gum extraction protocol, for a 1H-NMR-based metabolic profiling study of Xanthomonas, we tested four different interventions on the broadly used methanol-chloroform extraction protocol for the intracellular metabolic contents observation. Lower limits for bacterial pellet volumes for extraction were also probed, and a strategy is illustrated with an initial analysis of X. citri’s metabolism by 1H-NMR spectroscopy. PMID:24957023

  1. Gas chromatography-mass spectrometric analysis of products from on-line pyrolysis/silylation of plant gums used as binding media

    NASA Astrophysics Data System (ADS)

    Chiantore, Oscar; Riedo, Chiara; Scalarone, Dominique

    2009-07-01

    Plant gums are complex polysaccharides used in the field of cultural heritage especially as binding media. Classification of polysaccharides may be achieved on the basis of monosaccharides composition after cleavage of glycosidic bond. Characterization of plant gums in works of art is complicated by the necessity of to use a method minimally invasive and requiring a small mount of sample. Pyrolisys is an useful method to obtain polysaccharides decomposition and generally pyrolysis products can be identified by the use of gas chromatography-mass spectrometry. This paper describes a method where two plant gums, arabic and tragacanth, were pyrolized in presence of silylating agents (HMDS e BSTFA alone and with TMCS as catalyst) using an on-line Py-GC/MS apparatus. Some characteristic trimethylsilyl derivatives of monosaccharides were identified on the basis of mass spectra. The presence of characteristic pyrolysis products of sugars allows to distinguish the two gums.

  2. Low-fat sodium-reduced sausages: Effect of the interaction between locust bean gum, potato starch and ?-carrageenan by a mixture design approach.

    PubMed

    García-García, Elizabeth; Totosaus, Alfonso

    2008-04-01

    A mixture design approach was used to evaluate interactions between potato starch, locust bean gum and ?-carrageenan and their effect on cooking yield, expressible moisture, texture and color in low-fat sodium-reduced sausages formulated with potassium and calcium chloride. Starch had a notable influence on cooking yield and texture, increasing product hardness and resilience as starch proportion increased. The added salt did not allow complete starch granule gelatinization and swelling, which negatively affected water retention, cohesiveness and lightness. Locust bean gum and ?-carrageenan improved cooking yield and reduced expressible moisture in formulations containing higher proportions of potato starch. The presence of other ions could have enhanced ?-carrageenan functionality and its synergistic interaction with locust bean gum, improving texture and water retention, with only minor effects on sausage color. At the lower tested proportions starch can be used as an extender in low-fat cooked meat products if ?-carrageenan and locust bean gum are included in similar proportions. PMID:22062459

  3. Crystallization and Preliminary Crystallographic Characterization of GumK, A Membrane-Associated Gluocuronosyltransferase from Xanthomonas campestris Required for Xanthan Polysaccharide Synthesis

    SciTech Connect

    Barreras,M.; Bianchet, M.; Ielpi, L.; Tong, L.

    2006-01-01

    GumK is a membrane-associated inverting glucuronosyltransferase that is part of the biosynthetic route of xanthan, an industrially important exopolysaccharide produced by Xanthomonas campestris. The enzyme catalyzes the fourth glycosylation step in the pentasaccharide-P-P-polyisoprenyl assembly, an oligosaccharide diphosphate lipid intermediate in xanthan biosynthesis. GumK has marginal homology to other glycosyltransferases (GTs). It belongs to the CAZy family GT 70, for which no structure is currently available, and indirect biochemical evidence suggests that it also belongs to the GT-B structural superfamily. Crystals of recombinant GumK from X. campestris have been grown that diffract to 1.9 {angstrom} resolution. Knowledge of the crystal structure of GumK will help in understanding xanthan biosynthesis and its regulation and will also allow a subsequent rational approach to enzyme design and engineering. The multiwavelength anomalous diffraction approach will be used to solve the phase problem.

  4. In Vivo Evaluation of Modified Gum Karaya as a Carrier for Im proving the Oral Bioavailability of a Poorly Water-Soluble Drug, Nimodipine

    Microsoft Academic Search

    Gedela V. Murali; Mohan Babu; Namballa R. Kumar; Kasina H. Sankar; Battu J. Ram; K. Kumar; Kolapalli V. R. Murthy

    This work examines the influence of modified gum karaya (MGK) on the oral bioavailability of a poorly water-soluble drug, ni- modipine (NM), in comparison with that of gum karaya (GK). A cogrinding method was selected to prepare mixtures of NM and GK or MGK in a 1:9 ratio (NM:GK\\/MGK). Differential scanning calo- rimetry (DSC), Fourier transmission infrared (FT- IR) spectroscopy,

  5. In vivo evaluation of modified gum karaya as a carrier for improving the oral bioavailability of a poorly water-soluble drug, nimodipine

    Microsoft Academic Search

    Gedela V. Murali Mohan Babu; Namballa R. Kumar; Kasina H. Sankar; Battu J. Ram; Namburu K. Kumar; Kolapalli V. R. Murthy

    2002-01-01

    This work examines the influence of modified gum karaya (MGK) on the oral bioavailability of a poorly water-soluble drug,\\u000a nimodipine (NM), in comparison with that of gum karaya (GK). A cogrinding method was selected to prepare mixtures of NM and\\u000a GK or MGK in a 1:9 ratio (NM:GK\\/MGK). Differential scanning calorimetry (DSC), Fourier transmission infrared (FT-IR) spectroscopy,\\u000a X-ray diffraction (XRD),

  6. Formulation of Gluten-Free Pocket-Type Flat Breads: Optimization of Methylcellulose, Gum Arabic, and Egg Albumen Levels by Response Surface Methodology

    Microsoft Academic Search

    IMAD TOUFEILI; SHAWKY DAGHER; SOSSY SHADAREVIAN

    Response surface methodology was used to analyze the effects of methyl- cellulose, egg albumen, and gum arabic on the sensory properties of gluten- free pocket-type flat bread baked from formulas based on pregelatinized rice flour and pregelatinized corn starch with corn flour. A rotatable central-composite design consisting of three variables (methylcellulose, egg albumen, and gum arabic), in a five-level pattern

  7. Effect of chewing gums with xylitol, sorbitol and xylitol-sorbitol on the remineralization and hardness of initial enamel lesions in situ

    PubMed Central

    Tuncer, Duygu; Önen, Alev; Yazici, A. Rüya

    2014-01-01

    Background: The purpose of this study was to determine the effect of three chewing gums and paraffin on the remineralization and the hardness of demineralized enamel. Materials and Methods: A total of 12 subjects wore intraoral palatal appliances with two demineralized bovine enamel slabs. The study consisted of four experimental periods each lasting 21-days, during which subjects were assigned to one of three gum-chewing regimens: gum containing sorbitol, xylitol and a mixture of sorbitol and xylitol and with paraffin as control. The appliances were worn during gum-chewing for 20 min and then retained for 20 min 4 times/day. The slabs were subjected to energy dispersive X-ray spectroscopy analysis and surface microhardness measurements before in setting into the appliance and after the experimental period. The data were subjected to analysis of variance for repeated measures. A P < 0.05 was considered statistically significant. Results: Mineral analysis revealed no significant difference between the baseline and after chewing periods for all groups (P > 0.05). No significant difference was found among the groups either for the baseline measurements or after chewing periods (P > 0.05). All groups showed higher microhardness values after the chewing periods than the baseline except for the Vivident Xylit group (P < 0.05). Conclusion: The chewing of gum had no effect on the Ca/P ratio of demineralized enamel surfaces. The hardening of the demineralized enamel surfaces may vary according to the type of chewing gum. PMID:25426142

  8. Stabilization of water in oil in water (W/O/W) emulsion using whey protein isolate-conjugated durian seed gum: enhancement of interfacial activity through conjugation process.

    PubMed

    Tabatabaee Amid, Bahareh; Mirhosseini, Hamed

    2014-01-01

    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. PMID:24060935

  9. Star formation in BOK globules and low-mass clouds. I - The cometary globules in the GUM Nebula

    NASA Astrophysics Data System (ADS)

    Reipurth, B.

    1983-01-01

    Optical and IR photometry, together with red and blue spectra, show that Bernes 135 is a premain-sequence star of about 50 solar luminosities, 2.5-3 solar masses, and an effective temperature of 6800 K. While Bernes 135 is associated with the cometary globule CG 1 in the Gum Nebula, Bernes 136 is associated with the cometary globule CG 13 and is an early F-type field star whose radial velocity relative to the globule is 25.9 km/sec. While the main present source of UV radiation in the Gum Nebula is Zeta Puppis, the evaporation of the globules is not efficient enough to fully destroy any but the smallest modules during the remaining lifetime of Zeta Puppis. A scenario for module formation and evolution is suggested in which UV radiation from a massive O-star can destroy small neighboring clouds and separate less dense cloud material from cloud cores.

  10. Physicochemical responses and microbial characteristics of shiitake mushroom (Lentinus edodes) to gum arabic coating enriched with natamycin during storage.

    PubMed

    Jiang, Tianjia; Feng, Lifang; Zheng, Xiaolin; Li, Jianrong

    2013-06-01

    Physicochemical responses and microbial characteristics of shiitake mushroom (Lentinus edodes) to gum arabic (GA) coating incorporating natamycin (NA) during storage were investigated. Mushroom weight loss, firmness, total soluble solids, total sugar, reducing sugar, ascorbic acid, and microbial and sensory quality were measured. Mushroom coated with gum arabic+natamycin (GANA) maintained tissue firmness and showed reduction in microbial counts from yeasts and moulds compared with the control. In addition, GANA coating also delayed changes in the soluble solids concentration, total sugar and ascorbic acid. Sensory evaluation proved the efficacy of GANA coating by maintaining the overall quality of shiitake mushroom during the storage period. The efficiency was better than that of GA or NA treatment alone. Our study suggests that GANA has the potential to improve the quality of shiitake mushroom and extend its shelf-life up to 16d. PMID:23411335

  11. Effect of hydrophilic natural gums in formulation of oral-controlled release matrix tablets of propranolol hydrochloride.

    PubMed

    Rajesh, K S; Venkataraju, M P; Gowda, D V

    2009-04-01

    In order to develop a controlled delivery of highly water-soluble propranolol hydrochloride (PPHCl) using hydrophilic natural gums (xanthan gum [X] and locust bean gum [LBG]) as cost-effective, nontoxic, easily available. The granules of PPHCl were prepared by wet granulation method using a different ratios drug: gum ratios of X, LBG and XLBG(X and LBG in 1:1 ratios). To increase the flowability and compressibility of the granules, and to prevent its adhesion to punch and die, magnesium stearate and talc were added to the granules in 1:2 ratios before punching. The tablet was analysed to determine hardness, friability, % assay and invitro release study was carried out. The release of PPHCl from a gelatinous swollen mass, which controls the diffusion of drug molecules through the polymeric material into aqueous medium. The XLBG matrice shows precise controlled release than the X and LBG matrice because of burst effect and fast release in case of X and LBG matrice respectively and there was no chemical interaction between drug and polymer in XLBG formulation as confirmed by FTIR studies. First pass effect of PPHCl can be avoided by these formulations. Matrices with XLBG show zero-order release via swelling, diffusion and relaxation mechanism. The XLBG matrice leads to more precise result than X and LBG alone by the utilization of synergistic interaction between two biopolymers and uniformity in the hydration layer in dissolution media. However, according to the similarity factor (f(2)) XLBG3 were the most similar formulations to Lol-SR as the reference standard. PMID:19339235

  12. Suppressive effect of partially hydrolyzed guar gum on transitory diarrhea induced by ingestion of maltitol and lactitol in healthy humans

    Microsoft Academic Search

    S Nakamura; R Hongo; K Moji; T Oku

    2007-01-01

    Objectives:To estimate the suppressive effect of partially hydrolyzed guar gum (PHGG) on transitory diarrhea induced by ingestion of a sufficient amount of maltitol or lactitol in female subjects.Design:The first, the minimal dose level of maltitol and lactitol that would induce transitory diarrhea was estimated separately for each subject. Individual subject was administered a dose that increased by 5 g stepwise

  13. Whey Protein Concentrate and Gum Tragacanth as Fat Replacers in Nonfat Yogurt: Chemical, Physical, and Microstructural Properties

    Microsoft Academic Search

    S. Aziznia; A. Khosrowshahi; A. Madadlou; J. Rahimi

    2008-01-01

    The effect of whey protein concentrate (WPC) and gum tragacanth (GT) as fat replacers on the chemical, physical, and microstructural properties of nonfat yo- gurt was investigated. The WPC (7.5, 15, and 20 g\\/L) and GT (0.25, 0.5, 0.75, and 1 g\\/L) were incorporated into the skim milk slowly at 40 to 45°C with agitation. The yogurt mixes were pasteurized

  14. Colon Specific Delivery of Indomethacin: Effect of Incorporating pH Sensitive Polymers in Xanthan Gum Matrix Bases

    Microsoft Academic Search

    Laila F. A. Asghar; Chetan B. Chure; Sajeev Chandran

    2009-01-01

    In the present study, an attempt has been made to design controlled release colon-specific formulations of indomethacin by\\u000a employing pH responsive polymers Eudragit (L100 or S100) in matrix bases comprised of xanthan gum. The prepared tablets were\\u000a found to be of acceptable quality with low-weight variation and uniform drug content. In vitro release studies indicated rapid swelling and release of

  15. Postharvest application of gum arabic and essential oils for controlling anthracnose and quality of banana and papaya during cold storage

    Microsoft Academic Search

    Mehdi Maqbool; Asgar Ali; Peter G. Alderson; Mahmud Tengku Muda Mohamed; Yasmeen Siddiqui; Noosheen Zahid

    2011-01-01

    Management of anthracnose caused by Colletotrichum spp. is the most important issue for the tropical fruit industry because of resulting financial losses. Antifungal effects of gum arabic (GA) (10%), lemongrass oil (LG) (0.05%), cinnamon oil (CM) (0.4%), and their combinations were investigated in vitro and in vivo for controlling postharvest anthracnose of banana and papaya. LG at 0.05% and 0.4%

  16. Variations in compression strength and surface roughness of heat-treated Turkish river red gum ( Eucalyptus camaldulensis ) wood

    Microsoft Academic Search

    Oner Unsal; Nadir Ayrilmis

    2005-01-01

    This article reports the effects of heat treatment on compression strength parallel to the grain, the surface roughness [average roughness (Ra)], and the air-dry den-sity of wood from the river red gum tree (Eucalyptus camaldulensis Dehn.) planted in Turkey. Eucalyptus wood was heat-treated at temperatures varying from 120° to 180°C for durations of 2–10?h. Samples cut from the heat-treated wood

  17. [Effects of phosphorus stress on the growth and nitrogen and phosphorus absorption of different Formosan sweet gum provenances].

    PubMed

    Leng, Hua-Ni; Chen, Yi-Tai; Duan, Hong-Ping; Rao, Long-Bing; Wang, Yong-Jun; Hu, Yun-Xue

    2009-04-01

    Aiming at the ecological value of Formosan sweet gum (Liquidambar formosana) as a pioneer species and the status of red soil phosphorus (P) deficiency, a sand culture experiment of split design was conducted to study the responses of three-leaf stage seedlings of seven Formosan sweet gum provenances from Yixing of Jiangsu, Jingxian of Anhui, Yongkang of Zhejiang, Nanchang of Jiangxi, Shaowu of Fujian, Yanping of Fujian, and Nandan of Guangxi to four levels of P (P0, P1/2, P1, P2). With increasing P stress, the biomass and the N and P absorption of test provenances decreased, whereas the utilization efficiency increased. In higher P treatments, the provenances from Nanchang and Yixing had higher biomass and higher N and P absorption but lower utilization efficiency, while the provenance from Nandan had lower N and P absorption but higher utilization efficiency. In lower P treatments, the biomass and the P absorption and utilization efficiency of the provenances from Nanchang and Nandan were all higher. All the results illustrated that the provenances with high biomass had high P absorption at high P level, and had both high P absorption and high utilization efficiency at low P level. The provenance from Nanchang could be considered to be an excellent P stress-resistant provenance, followed by that from Nandan. Phosphorus was not a limiting nutritional factor of Formosan sweet gum, biomass, leaf delta (N/P) ratio and P efficiency could be used as the indicators of P stress-tolerance of Formosan sweet gum provenances. PMID:19565751

  18. Water consumption of a six-year-old river red gum plantation in the Southern Zagros Mountains, Iran

    Microsoft Academic Search

    Masoud Edraki; Sayyed Ahang Kowsar; Ali Asghar Mehrbakhsh; Ali Bordbar

    2007-01-01

    Water is the most important limiting factor in the development of arid environments; therefore, optimization of water use\\u000a is a necessity in desert reclamation projects. Evapotranspiration of a 6-year-old river red gum (Eucalyptus camaldulensis Dehnh.) plantation, located in a sedimentation basin of an artificial recharge of the Gareh Bygone Plain groundwater system\\u000a in Iran’s southern Zagros Mountains, was studied during

  19. Rheological characterization of mayonnaise. Part II: Flow and viscoelastic properties at different oil and xanthan gum concentrations

    Microsoft Academic Search

    L. Ma; G. V. Barbosa-Cánovas

    1995-01-01

    The flow and viscoelastic properties of mayonnaise at different oil and xanthan gum concentrations (75–85% and 0.5–1.5% (w\\/w), respectively) were investigated in the rotational and oscillatory mode using a plate-plate rheometer. Yield stress, which was determined using a static method, and steady measurements were corrected to account for slippage. The corrected flow curves were fitted with the Herschel-Bulkley model, and

  20. Effect of xanthan gum on physicochemical properties of whey protein isolate stabilized oil-in-water emulsions

    Microsoft Academic Search

    Changhui Sun; Sundaram Gunasekaran; Mark P. Richards

    2007-01-01

    The effect of xanthan gum (XG) addition on physicochemical properties of 2wt% whey protein isolate (WPI) stabilized oil-in-water (O\\/W) emulsions containing 20% v\\/v menhaden oil was investigated by measuring droplet size, viscosity, microstructure, creaming profile and oxidative stability. In fresh emulsions, addition of XG at different concentrations did not show any significant effect on the surface-area-average droplet size (d32). However,

  1. Formulation and In Vitro Evaluation of Xanthan Gum or Carbopol 934Based Mucoadhesive Patches, Loaded with Nicotine

    Microsoft Academic Search

    Rana Abu-Huwaij; Rana M. Obaidat; Kamal Sweidan; Yusuf Al-Hiari

    2011-01-01

    Bilayer nicotine mucoadhesive patches were prepared and evaluated to determine the feasibility of the formulation as a nicotine\\u000a replacement product to aid in smoking cessation. Nicotine patches were prepared using xanthan gum or carbopol 934 as a mucoadhesive\\u000a polymers and ethyl cellulose as a backing layer. The patches were evaluated for their thickness, weight and content uniformity,\\u000a swelling behavior, drug–polymers

  2. Effectiveness of resistant starch, compared to guar gum, in depressing plasma cholesterol and enhancing fecal steroid excretion

    Microsoft Academic Search

    Marie-Anne Levrat; Corinne Moundras; Hassan Younes; Christine Morand; Christian Demigné; Christian Rémésy

    1996-01-01

    Amylase-resistant starch (RS) represents a substrate that can be administered in substantial amounts in the diet, in contrast\\u000a to gel-forming polysaccharides, such as guar gum (GG). The aim of this work was thus to compare the effects of GG and RS on\\u000a cholesterol metabolism in rats adapted to 0.4% cholesterol diets, using dietary GG or RS levels (8 or 20%,

  3. Rheological characteristics of cold thickened beverages containing xanthan gum-based food thickeners used for dysphagia diets.

    PubMed

    Cho, Hyun M; Yoo, Byoungseung

    2015-01-01

    Cold beverages are commonly thickened with commercial gum-based food thickeners for consumption by patients with dysphagia. In this study, the rheological properties of a thickened water and five thickened beverages (orange juice, apple juice, grape juice, whole milk, and a sport drink) that were prepared with four commercial instant xanthan gum-based thickeners (coded A-D) were investigated at a 3% thickener concentration. All thickened samples showed high shear-thinning behavior with yield stress at the serving temperature of 8°C. The magnitudes of apparent viscosity (?a,50), consistency index (K), storage modulus (G'), and loss modulus (G'') of the thickened beverages, except for water, with food thickener A were significantly higher compared with other thickeners (B, C, and D) (P<0.05). The largest increases in K values for thickened beverages were observed at 1-hour storage, and at longer times their K values, except for milk, remained approximately constant. Rheological parameters demonstrated statistically significant differences in flow and dynamic behaviors between the cold thickened beverages prepared with the xanthan gum-based food thickeners (P<0.05), indicating that their rheological properties are strongly influenced by the dispersing medium, the type of food thickener, and storage time. In particular, appropriately selecting a commercial food thickener for preparing thickened beverages seems to be of importance for managing dysphagia. PMID:25441963

  4. Relation between information and advice provision to male GUM clinic attendees and sexual orientation and ethnic group

    PubMed Central

    Hope, V.; MacArthur, C.; Mullis, D.; Radcliffe, K.

    2000-01-01

    Objectives: To examine whether the provision of advice and information to male genitourinary medicine (GUM) clinic attendees was related to their reasons for attendance, ethnicity, or sexual orientation. Method: Cross sectional survey of men attending a large city centre GUM clinic. Data were collected using an anonymous subject completed questionnaire. Results: Of the 302 men recruited, 72% described themselves as white and 85% reported only female sexual partners. Information and advice provision were generally found to reflect reason for attendance—for example, those attending with a concern about "an STD or urinary problem" were more likely to report advice and information on NSU/chlamydia, herpes, gonorrhoea, or syphilis than those attending without such concerns. For those attending with a concern about HIV less than half (42%) reported receiving advice and information about HIV. The reasons for attendance were found to vary with ethnicity (black men were more likely to attend for a "check up," and less likely to attend about HIV or with genital warts than white men) and sexual orientation (those with male partners were more likely to attend about HIV or hepatitis B than those with only female partners); there were corresponding variations in the provision of advice and information. Conclusions: The clinic was generally providing advice and information appropriate to the reasons for attendance and this reflected variations in such needs with ethnicity and sexual orientation. The provision of advice and information about HIV could be more comprehensive. Key Words: advice; male GUM clinic attendees; sexual orientation; ethnic group PMID:10961198

  5. Rheological and kinetic study of the ultrasonic degradation of xanthan gum in aqueous solution: effects of pyruvate group.

    PubMed

    Li, Ruoshi; Feke, Donald L

    2015-06-25

    The influence of the pyruvate group on the efficiency of ultrasonic degradation of xanthan gum in aqueous solution has been studied. Blends of natural and pyruvate-free xanthan gums were ultrasonicated at 20°C for up to 30min and evaluated for molecular-weight degradation by viscometry. Solutions of pure pyruvate-free xanthan exhibited the highest stability to degradation among all blend ratios studied. Removing the pyruvate group is believed to enable the molecular chains to adopt a more compact conformation, which renders the polymer less susceptible to ultrasonication. In addition, the effects of salt on ultrasonic degradation efficiency were studied by using 0.1, 10(-2), or 10(-4)M of NaCl or Na2SO4 in solution prior to ultrasonication. A degradation kinetics model was developed to quantify the degradation behavior. The absence of pyruvate groups renders the xanthan gum less sensitive to the influence of salt, and hence decreases the ultrasonic degradation efficiency. PMID:25839814

  6. Rhamsan gum production by Sphingomonas sp. CGMCC 6833 using a two-stage agitation speed control strategy.

    PubMed

    Xu, Xiao Ying; Zhu, Ping; Li, Sha; Chen, Xiao Ye; Jiang, Xing Huan; Xu, Hong

    2013-12-19

    Varying the agitation speed could greatly affect rhamsan gum production by Sphingomonas sp. CGMCC 6833. Batch fermentations at agitation speeds of 400, 600, 800, and 1,000 rpm were therefore carried out. The time course of specific cell growth rate, specific glucose consumption rate, and specific rhamsan gum formation rate was subsequently determined. Based on the results, a novel two-stage agitation speed control strategy was developed. From 0 to 13 H, the high specific cell growth and glucose consumption rates were achieved by setting the agitation speed of the fermenter at 800 rpm. From 13 H onward to the end of fermentation, the glucose consumption rate and specific cell growth rate were high at the agitation speed of 600 rpm. Using this method, the maximum concentration and productivity of rhamsan gum reached 21.63 ± 1.76 g L(-1) and 0.338 ± 0.028 g L(-1)  H(-1) , respectively, which were both higher than the optimum results obtained at constant agitation speeds. PMID:24354661

  7. Effect of spray drying on the sensory and physical properties of hydrolysed casein using gum arabic as the carrier.

    PubMed

    Subtil, S F; Rocha-Selmi, G A; Thomazini, M; Trindade, M A; Netto, F M; Favaro-Trindade, C S

    2014-09-01

    This study was aimed at spray drying hydrolysed casein using gum Arabic as the carrier agent, in order to decrease the bitter taste. Three formulations with differing proportions of hydrolysed casein: gum Arabic (10:90, 20:80 and 30:70) were prepared and characterized. They were evaluated for their moisture content, water activity, hygroscopicity, dispersibility in water and in oil, particle size and distribution, particle morphology, thermal behaviour (DSC) and bitter taste by a trained sensory panel using a paired-comparison test (free samples vs. spray dried samples). The proportion of hydrolysed casein did not affect the morphology of the microspheres. The spray drying process increased product stability and modified the dissolution time, but had no effect on the ability of the material to dissolve in either water or oil. The sensory tests showed that the spray drying process using gum Arabic as the carrier was efficient in attenuating or masking the bitter taste of the hydrolysed casein. PMID:25190858

  8. Natural gum as mucoadhesive controlled release carriers: evaluation of cefpodoxime proxetil by D-optimal design technique.

    PubMed

    Patil, Satish H; Talele, Gokul S

    2014-03-01

    The present study deals with the development of mucoadhesive controlled release tablets of Cefpodoxime Proxetil to increase the gastric residence time and thus prolong drug release, reduce dosing frequency and improve oral bioavailability. Tablets were prepared using sodium alginate and karaya gum, a natural polymer, with a synthetic polymer hydroxypropylmethylcellulose (K100LV) and Karaya gum with HPMC K100LV in various ratios to optimize the drug release profile using D-Optimal technique. Pre- and post-compression parameters of tablets prepared with various formulations (S1-S9, C1-C9) were evaluated. The FTIR and DSC studies revealed that no physiochemical interaction between excipients and drug. The formulation S7 showed prolonged drug release, and the mechanism of drug release from the optimized formulation was confirmed using the Korsmeyer-Peppas model to be non-Fickian release transport and n value was found 0.605 indicating both diffusion and erosion mechanism from these natural gums. The optimized formulation showed mucoadhesive strength >35?g. An in vivo study was performed on rabbits using an X-ray imaging technique. The radiological evidence suggests that the tablets adheres (more than 10 hours) to a rabbit's stomach. No significant changes were found in the physical appearance, drug content, mucoadhesive study and in vitro dissolution pattern after storage at 40?°C/75% relative humidity for 3 months. PMID:24032629

  9. Improving the stability of coal slurries: Final report. [Polygalacturonic acid and gum tragacanth

    SciTech Connect

    Fogler, H.S.

    1988-12-01

    Polysaccharides were found to stabilize colloidal dispersions (such as coal particles and polystyrene latex particles) even at high ionic strengths. The stability studies with various kinds of polysaccharides showed that rod-like molecules (such as poly (galacturonic acid) and gum tragacanth) are much more effective stabilizers than highly-branched molecules such as arabinogalactan. This effective stabilization with the rod-like molecules was found to result from the adsorption of polysaccharides on the particles, i.e., the steric stabilization mechanism. The stability depends significantly on the solution pH, the molecular weight and the surface charge of particles. Adsorption isotherms, the zeta potential and the conformation of adsorbed molecules (the steric layer thicknesses) were measured as a function of the solution pH, the molecular weight and the surface charge. Photon correlation spectroscopy studies showed that the conformation of adsorbed molecules is strongly dependent on the solution pH, the molecular weight and the surface charge, suggesting that the dependence of stability on these parameters is due to the change of the conformation of the molecules adsorbed on the surface. In addition, the solution pH has a significant effect on the flocculation behavior of particles and can be modulated to bring about peptization of particles. This type of stabilization is referred to as electrosteric stabilization whereby steric stabilization is induced by changing the electrical properties of the system (the solution pH in this case). 41 refs., 43 figs., 10 tabs.

  10. A comparison of the sensory and rheological properties of molecular and particulate forms of xanthan gum?

    PubMed Central

    Abson, Rachael; Gaddipati, Sanyasi R.; Hort, Joanne; Mitchell, John R.; Wolf, Bettina; Hill, Sandra E.

    2014-01-01

    A particulate form of xanthan gum was prepared by extrusion cooking. The temperature dependence of the viscosity of this form shows similarities to starch with an increase in viscosity to a maximum with increasing temperature as a result of the swelling of the particles. The rheology and mixing behaviour with water of the particulate and conventional molecular forms of xanthan were compared with a modified starch. The particulate xanthan products mixed rapidly with water in a similar way to ungelatinised starch, whereas conventional molecular xanthan systems mixed poorly. Using an experienced sensory panel, model tomato products thickened with the three systems were compared at equal shear viscosities. The panel could not discriminate between the tomato flavour of the three products, but found that the xanthan products were perceived as being significantly thicker. These observations were consistent with previous work. Salt perception for both xanthan products was poorer than for the starch thickened systems. A hypothesis to explain why xanthan does not fit into the previously postulated link between mixing and perception is presented. PMID:24591753

  11. Glucuronoarabinoxylan from coconut palm gum exudate: chemical structure and gastroprotective effect.

    PubMed

    Simas-Tosin, Fernanda F; Barraza, Ruth R; Maria-Ferreira, Daniele; Werner, Maria Fernanda de P; Baggio, Cristiane H; Wagner, Ricardo; Smiderle, Fhernanda R; Carbonero, Elaine R; Sassaki, Guilherme L; Iacomini, Marcello; Gorin, Philip A J

    2014-07-17

    A glucuronoarabinoxylan (CNAL) was extracted with 1% aq. KOH (25°C) from Cocos nucifera gum exudate. It had a homogeneous profile on HPSEC-MALLS-RI (Mw 4.6 × 10(4)g/mol) and was composed of Fuc, Ara, Xyl, GlcpA (and 4-O-GlcpA) in a 7:28:62:3 molar ratio. Methylation data showed a branched structure with 39% of non-reducing end units, 3-O-substituted Araf (8%), 3,4-di-O- (15%), 2,4-di-O- (5%) and 2,3,4-tri-O-substituted Xylp units (17%). The anomeric region of CNAL (13)C NMR spectrum contained 9 signals, indicating a complex structure. The main chain of CNAL was characterized by analysis of a Smith-degraded polysaccharide. Its (13)C NMR spectrum showed 5 main signals at ? 101.6, ? 75.5, ? 73.9, ? 72.5, and ? 63.1 that were attributed to C-1, C-4, C-3, C-2 and C-5 of (1?4)-linked ?-Xylp-main chain units, respectively. CNAL exhibited gastroprotective effect, by reducing gastric hemorrhagic lesions, when orally administered (1 and 3mg/kg) to rats prior to ethanol administration. PMID:24702919

  12. Milk protein-gum tragacanth mixed gels: effect of heat-treatment sequence.

    PubMed

    Hatami, Masoud; Nejatian, Mohammad; Mohammadifar, Mohammad Amin; Pourmand, Hanieh

    2014-01-30

    The aim of this study was to investigate the role of the heat-treatment sequence of biopolymer mixtures as a formulation parameter on the acid-induced gelation of tri-polymeric systems composed of sodium caseinate (Na-caseinate), whey protein concentrate (WPC), and gum tragacanth (GT). This was studied by applying four sequences of heat treatment: (A) co-heating all three biopolymers; (B) heating the milk-protein dispersion and the GT dispersion separately; (C) heating the dispersion containing Na-caseinate and GT together and heating whey protein alone; and (D) co-heating whey protein with GT and heating Na-caseinate alone. According to small-deformation rheological measurements, the strength of the mixed-gel network decreased in the order: C>B>D>A samples. SEM micrographs show that the network of sample C is much more homogenous, coarse and dense than sample A, while the networks of samples B and D are of intermediate density. The heat-treatment sequence of the biopolymer mixtures as a formulation parameter thus offers an opportunity to control the microstructure and rheological properties of mixed gels. PMID:24299875

  13. Xanthan gum as an adjuvant in a subunit vaccine preparation against leptospirosis.

    PubMed

    Bacelo, Katia L; Hartwig, Daiane D; Seixas, Fabiana K; Schuch, Rodrigo; Moreira, Angelita da S; Amaral, Marta; Collares, Tiago; Vendrusculo, Claire T; McBride, Alan J A; Dellagostin, Odir A

    2014-01-01

    Leptospiral immunoglobulin-like (Lig) proteins are of great interest due to their ability to act as mediators of pathogenesis, serodiagnostic antigens, and immunogens. Purified recombinant LigA protein is the most promising subunit vaccine candidate against leptospirosis reported to date, however, as purified proteins are weak immunogens the use of a potent adjuvant is essential for the success of LigA as a subunit vaccine. In the present study, we compared xanthan pv. pruni (strain 106), aluminium hydroxide (alhydrogel), and CpG ODN as adjuvants in a LigA subunit vaccine preparation. Xanthan gum is a high molecular weight extracellular polysaccharide produced by fermentation of Xanthomonas spp., a plant-pathogenic bacterium genus. Preparations containing xanthan induced a strong antibody response comparable to that observed when alhydrogel was used. Upon challenge with a virulent strain of L. interrogans serovar Copenhageni, significant protection (Fisher test, P < 0.05) was observed in 100%, 100%, and 67% of hamsters immunized with rLigANI-xanthan, LigA-CpG-xanthan, and rLigANI-alhydrogel, respectively. Furthermore, xanthan did not cause cytotoxicity in Chinese hamster ovary (CHO) cells in vitro. The use of xanthan as an adjuvant is a novel alternative for enhancing the immunogenicity of vaccines against leptospirosis and possibly against other pathogens. PMID:24895594

  14. Extraction, characterization and application of malva nut gum in water treatment.

    PubMed

    Ho, Y C; Norli, I; Alkarkhi, Abbas F M; Morad, N

    2015-06-01

    In view of green developments in water treatment, plant-based flocculants have become the focus due to their safety, degradation and renewable properties. In addition, cost and energy-saving processes are preferable. In this study, malva nut gum (MNG), a new plant-based flocculant, and its composite with Fe in water treatment using single mode mixing are demonstrated. The result presents a simplified extraction of the MNG process. MNG has a high molecular weight of 2.3 × 10(5) kDa and a high negative charge of -58.7 mV. From the results, it is a strong anionic flocculant. Moreover, it is observed to have a branch-like surface structure. Therefore, it conforms to the surface of particles well and exhibits good performance in water treatment. In water treatment, the Fe-MNG composite treats water at pH 3.01 and requires a low concentration of Fe and MNG of 0.08 and 0.06 mg/L, respectively, when added to the system. It is concluded that for a single-stage flocculation process, physico-chemical properties such as molecular weight, charge of polymer, surface morphology, pH, concentration of cation and concentration of biopolymeric flocculant affect the flocculating performance. PMID:26042980

  15. Evaluation of Chios mastic gum on lipid and glucose metabolism in diabetic mice.

    PubMed

    Georgiadis, Ioannis; Karatzas, Theodore; Korou, Laskarina-Maria; Agrogiannis, George; Vlachos, Ioannis S; Pantopoulou, Alkisti; Tzanetakou, Irene P; Katsilambros, Nikolaos; Perrea, Despina N

    2014-03-01

    Chios mastic gum (MG), a resin produced from Pistacia lentiscus var. Chia, is reported to possess beneficial cardiovascular and hepatoprotective properties. This study investigated the effect of crude Chios MG on metabolic parameters in diabetic mice. Streptozotocin-induced diabetic 12-week-old male C57bl/6 mice were assigned to three groups: NC (n=9) control; LdM (n=9) animals receiving low dose mastic for 8 weeks (20?mg/kg body weight [BW]); and HdM (n=9) animals receiving high dose mastic (500?mg/kg BW) for the same period. Serum lipid and glucose levels were determined at baseline, at 4 and 8 weeks. Serum total protein, adiponectin, and resistin levels were also measured at the end of the experiment. Histopathological examination for liver, kidney, aorta, and heart lesions was performed. After 4 weeks, MG administration resulted in decreased serum glucose and triglyceride levels in both LdM and HdM, whereas BW levels were reduced in LdM group compared with controls. At the end of the experiment, LdM presented significantly lower serum glucose, cholesterol, low-density lipoprotein cholesterol, and triglyceride levels and improved high-density lipoprotein cholesterol levels compared with control group. HdM group had ameliorated serum triglyceride levels. Hepatic steatosis observed in control group was partially reversed in LdM and HdM groups. MG administered in low dosages improves glucose and lipid disturbances in diabetic mice while alleviating hepatic damage. PMID:24404977

  16. Peroxidase-mediated conjugation of corn fiber gum and bovine serum albumin to improve emulsifying properties.

    PubMed

    Liu, Yan; Qiu, Shuang; Li, Jinlong; Chen, Hao; Tatsumi, Eizo; Yadav, Madhav; Yin, Lijun

    2015-03-15

    The emulsifying properties of corn fiber gum (CFG), a naturally occurring polysaccharide-protein complex, was improved by kinetically controlled formation of hetero-covalent linkages with bovine serum albumin (BSA), using horseradish peroxidase (HRP). The formation of hetero-crosslinked CFG-BSA conjugates was confirmed using ultraviolet-visible and Fourier-transform infrared analyses. The optimum CFG-BSA conjugates were prepared at a CFG:BSA weight ratio of 10:1, and peroxidase:BSA weight ratio of 1:4000. Selected CFG-BSA conjugates were used to prepare oil-in-water emulsions; the emulsifying properties were better than those of emulsions stabilized with only CFG or BSA. Measurements of mean droplet sizes and zeta potentials showed that CFG-BSA-conjugate-stabilized emulsions were less susceptible to environmental stresses, such as pH changes, high K ionic strengths, and freeze-thaw treatments than CFG- or BSA-stabilized emulsions. These conjugates have potential applications as novel emulsifiers in food industry. PMID:25542109

  17. Effects of corn fiber gum (CFG) on the pasting and thermal behaviors of maize starch.

    PubMed

    Qiu, Shuang; Yadav, Madhav P; Chen, Hao; Liu, Yan; Tatsumi, Eizo; Yin, Lijun

    2015-01-22

    Corn fiber gum (CFG) was a novel arabinoxylan hydrocolloid and recent researches showed its considerable potential in food processing. In this study, the interactions of maize starch and CFG were studied. Maize starch/CFG blend gels were prepared from maize starch suspension mixing with 0.1%, 0.25%, 0.5%, 1.0% (w/w) CFG. The pasting and thermal properties, rheological properties, microstructure, leached amylose and swelling power characteristics were evaluated. Compared with the reference, CFG addition lowered peak viscosity and breakdown of the composite system, but increased final viscosity in RVA measurement. The swelling power and the amount of leached amylose of maize starch gels were reduced as the addition concentration of CFG increased. The thermal characteristics of maize starch/CFG mixtures varied insignificantly as determined in DSC heating process. Rheological parameters, such as storage modulus (G') and loss modulus (G"), of the maize starches were observed to increase when CFG was present, supporting the hypothesis that the interaction between CFG and amylose could happen in the composite system. Confocal laser scanning microscopy (CLSM) confirmed changes in gels microstructure as starch components tended to be inhibited from leaching out of the granules when CFG was added, and the morphology of starch granule was more compact when CFG was added. PMID:25439892

  18. Alginate/cashew gum floating bead as a matrix for larvicide release.

    PubMed

    Paula, Haroldo C B; de Oliveira, Erick F; Abreu, Flávia O M S; de Paula, Regina C M

    2012-08-01

    A polymeric floating system composed of Alginate (ALG) and Cashew gum (CG), loaded with an essential oil (Lippia sidoides-Ls) was prepared by ionotropic gelation, characterized regarding its physical-chemistry properties and evaluated on its potential as a controlled release system. The influence of process parameters on the buoyancy, loading, swelling and in vitro and in vivo release kinetics, was investigated. Results showed that beads produced with carbonate and Ls at high level contents exhibit good floatability (up to 5 days) and loading capacity (15.2-23.8%). In vitro release data showed a Fickian diffusion profile and in vivo experiments showed that ALG-CG floating system presented a superior and prolonged larvicide effect, in comparison with non-floating ones, presenting larvae mortality values of 85% and 33%, respectively, after 48 h. These results indicate that ALG-CG floating beads loaded with Ls presented enhanced oil entrapment efficiency, excellent floating ability, and suitable larvicide release pattern. PMID:24364941

  19. Effect of Gum arabic on distribution behavior of nanocellulose fillers in starch film

    NASA Astrophysics Data System (ADS)

    Vigneshwaran, Nadanathangam; Ammayappan, L.; Huang, Qingrong

    2011-09-01

    Uniform distribution of nanofillers in polymer matrix is posing a major challenge in exploiting the full potential of nanomaterials. Various fillers are being evaluated to improve the performance of biopolymer films like starch. In this work, nanocellulose is used as fillers to increase the performance characteristics of starch film. Due to high surface energy and hydrophilic nature of nanocellulose, they tend to aggregate during the film forming process. To circumvent this problem, Gum arabic (GA) was added to distribute the nanocellulose uniformly. GA helps in reduction of surface energy (as analyzed by contact angle) and thus facilitates the uniform distribution of nanocellulose (as demonstrated through polarized light microscopy). Nanocellulose as filler improved the tensile strength of starch film by 2.5 times while that of uniformly distributed nanocellulose by 3.5 times. Moreover, while nanocellulose as such could reduce the water vapor permeability of starch film by 1.4 times, uniformly distributed nanocellulose reduced it by 2 times proving the importance of GA. Starch film filled with nanocellulose and GA will be a 100% biopolymer-based system having potential demand in eco-friendly applications.

  20. Transcriptome analysis of a subtropical deciduous tree: autumn leaf senescence gene expression profile of formosan gum.

    PubMed

    Wen, Chi-Hsiang; Lin, Shih-Shun; Chu, Fang-Hua

    2015-01-01

    Autumn leaf senescence is a spectacular natural phenomenon; however, the regulation networks controlling autumnal colors and the leaf senescence program remain largely unelucidated. Whether regulation of leaf senescence is similar in subtropical deciduous plants and temperate deciduous plants is also unknown. In this study, the gene expression of a subtropical deciduous tree, Formosan gum (Liquidambar formosana Hance), was profiled. The transcriptomes of April leaves (green leaves, 'G') and December leaves (red leaves, 'R') were investigated by next-generation gene sequencing. Out of 58,402 de novo assembled contigs, 32,637 were annotated as putative genes. Furthermore, the L. formosana-specific microarray designed based on total contigs was used to extend the observation period throughout the growing seasons of 2011-2013. Network analysis from the gene expression profile focused on the genes up-regulated when autumn leaf senescence occurred. LfWRKY70, LfWRKY75, LfWRKY65, LfNAC1, LfSPL14, LfNAC100 and LfMYB113 were shown to be key regulators of leaf senescnece, and the genes regulated by LfWRKY75, LfNAC1 and LfMYB113 are candidates to link chlorophyll degradation and anthocyanin biosynthesis to senescence. In summary, the gene expression profiles over the entire year of the developing leaf from subtropical deciduous trees were used for in silico analysis and the putative gene regulation in autumn coloration and leaf senescence is discussed in this study. PMID:25392065

  1. Okra (Hibiscus esculentus) gum-alginate blend mucoadhesive beads for controlled glibenclamide release.

    PubMed

    Sinha, Priyanka; Ubaidulla, U; Nayak, Amit Kumar

    2015-01-01

    The utility of isolated okra (Hibiscus esculentus) gum (OG) was evaluated as a potential sustained drug release polymer-blends with sodium alginate in the development of controlled glibenclamide release ionically-gelled beads for oral use. OG was isolated from okra fruits and its solubility, pH, viscosity and moisture content were studied. Glibenclamide-loaded OG-alginate blend beads were prepared using CaCl2 as cross-linking agent through ionic-gelation technique. These ionically gelled beads showed drug entrapment efficiency of 64.19 ± 2.02 to 91.86 ± 3.24%. The bead sizes were within 1.12 ± 0.11 to 1.28 ± 0.15 mm. These glibenclamide-loaded OG-alginate blend beads exhibited sustained in vitro drug release over a prolonged period of 8 h. The in vitro drug release from these OG-alginate beads were followed controlled-release (zero-order) pattern with super case-II transport mechanism. The beads were also characterized by SEM and FTIR. The swelling and degradation of these beads was influenced by the pH of the test medium. These beads also exhibited good mucoadhesivity with goat intestinal mucosa. PMID:25312603

  2. Characterisation of Adaptive Genetic Diversity in Environmentally Contrasted Populations of Eucalyptus camaldulensis Dehnh. (River Red Gum)

    PubMed Central

    Dillon, Shannon; McEvoy, Rachel; Baldwin, Darren S.; Rees, Gavin N.; Parsons, Yvonne; Southerton, Simon

    2014-01-01

    As an increasing number of ecosystems face departures from long standing environmental conditions under climate change, our understanding of the capacity of species to adapt will become important for directing conservation and management of biodiversity. Insights into the potential for genetic adaptation might be gained by assessing genomic signatures of adaptation to historic or prevailing environmental conditions. The river red gum (Eucalyptus camaldulensis Dehnh.) is a widespread Australian eucalypt inhabiting riverine and floodplain habitats which spans strong environmental gradients. We investigated the effects of adaptation to environment on population level genetic diversity of E. camaldulensis, examining SNP variation in candidate gene loci sampled across 20 climatically diverse populations approximating the species natural distribution. Genetic differentiation among populations was high (FST?=?17%), exceeding previous estimates based on neutral markers. Complementary statistical approaches identified 6 SNP loci in four genes (COMT, Dehydrin, ERECTA and PIP2) which, after accounting for demographic effects, exhibited higher than expected levels of genetic differentiation among populations and whose allelic variation was associated with local environment. While this study employs but a small proportion of available diversity in the eucalyptus genome, it draws our attention to the potential for application of wide spread eucalypt species to test adaptive hypotheses. PMID:25093589

  3. Structural data and biological properties of almond gum oligosaccharide: application to beef meat preservation.

    PubMed

    Bouaziz, Fatma; Helbert, Claire Boisset; Romdhane, Molka Ben; Koubaa, Mohamed; Bhiri, Fatma; Kallel, Fatma; Chaari, Fatma; Driss, Dorra; Buon, Laurine; Chaabouni, Semia Ellouz

    2015-01-01

    Enzymatic hydrolysis of almond gum generates low molecular weight oligosaccharides (OAG) with a yield of 33.5%. The generated oligosaccharides were purified and identified. OAG analyses show that the most prominent residues were galactose and arabinose with traces of xylose, rhamnose, glucose and mannose. The glycosyl linkage positions were analyzed using gas chromatography-mass spectrometry showing a main chain composed of galactose units [ ? 3)-Gal-(1 ? ] branched mainly with arabinose residues [Ara-(1 ? ]. The antioxidant and antimicrobial activities of OAG were investigated. As regards the in vitro antioxidant activities, the OAG showed a high total antioxidant activity (347 ?g ascorbic acid equivalent/mL), an important DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging activity (IC50 = 0.64 mg/mL) and a high reducing capacity (RP0.5AU = 3.6 mg/mL). Furthermore, OAG had a high antimicrobial activity against Salmonella thyphimirium, Bacillus cereus, Actinomycetes sp, Klebsiella pneumoniae, Escherichia coli, Alternaria alternate and Candidat albicans. Finally, OAG efficiency was tested using 0.5%; 0.75% and 1% concentrations in beef meat preservation. Microbial growth and lipid oxidation were monitored during 9 days at 4 °C. The results showed significant inhibitions (p < 0.05) of lipid oxidation and microbial growth in ground beef meat containing OAG. PMID:25195541

  4. Optimization of an aqueous tablet-coating process containing carboxymethylated Cassia fistula gum.

    PubMed

    Rai, Parshu Ram; Tiwary, Ashok Kumar; Rana, Vikas

    2012-06-01

    The present investigation was aimed at developing and optimizing a simple aqueous tablet-coating formulation and its process. 5-Fluorouracil (5-FU) was used to ascertain the relative lipophilic/hydrophilic behavior of the coating system. Optimization was performed by evaluating the adhesive force strength and cohesive force strength of the tablet coat using a texture analyzer. The in vitro release of 5-FU was found to decrease with an increase in (tablet surface-coat) adhesive force strength. The (tablet-tablet) cohesive force strength was reduced by the addition of magnesium silicate to the coating solution. The addition of magnesium silicate (0.2% w/v) to the carboxymethyl Cassia fistula gum-chitosan (CCG-CH) coating surface significantly inhibited the release of 5-FU possibly due to an increase in the hydrophobic character of the coated tablet surface. This was possible by coating cohesive force strength reduction coating compositions (CCG-CH (70:30) and 0.3% magnesium silicate). Further, the FTIR-ATR and DSC analyses suggested the pivotal role of magnesium silicate in modifying the release of 5-FU from CCG-CH-coated tablets due to hydrogen bonding of its Si-O-Si or Mg-O groups with -OH moieties of CCG-CH. PMID:22362140

  5. Psyllium husk gum: an attractive carbohydrate biopolymer for the production of stable canthaxanthin emulsions.

    PubMed

    Gharibzahedi, Seyed Mohammad Taghi; Razavi, Seyed Hadi; Mousavi, Seyed Mohammad

    2013-02-15

    The physical stability of the ultrasonically prepared emulsions containing canthaxanthin (CX) produced by Dietzia natronolimnaea HS-1 strain was maximized using a face central composite design (FCCD) of response surface methodology (RSM). The linear and interaction effects of main emulsion components (whey protein isolate (WPI, 0.4-1.2 wt%), psyllium husk gum (PHG, 1.5-4.5 wt%) and coconut oil (CO, 5-10 wt%)) on the stability were studied. The density, turbidity and droplet size of emulsions were also characterized to interpret the stability data. A significant second-order polynomial model was established (p<0.0001). Maximum stability of 98.8% was predicted at the optimum levels of formulation variables (WPI concentration 1.20 wt%, PHG content 3.30 wt%, CO concentration 5.43 wt%). The results also demonstrated that CO and WPI concentration had greater effect on the droplet size and density values, whereas the PHG:WPI ratio had a rather greater effect on the turbidity values. PMID:23399251

  6. Preparation and in vitro evaluation of xanthan gum facilitated superabsorbent polymeric microspheres.

    PubMed

    Bhattacharya, Shiv Sankar; Mazahir, Farhan; Banerjee, Subham; Verma, Anurag; Ghosh, Amitava

    2013-10-15

    Interpenetrating polymer network (IPN) hydrogel microspheres of xanthan gum (XG) based superabsorbent polymer (SAP) and poly(vinyl alcohol) (PVA) were prepared by water-in-oil (w/o) emulsion crosslinking method for sustained release of ciprofloxacin hydrochloride (CIPRO). The microspheres were prepared with various ratios of hydrolyzed SAP to PVA and extent of crosslinking density. The prepared microspheres with loose and rigid surfaces were evidenced by scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis confirmed the IPN formation. Differential scanning calorimetry (DSC) study was performed to understand the dispersion nature of drug after encapsulation. The in vitro drug release study was extensively evaluated depending on the process variables in both acidic and alkaline media. All the formulations exhibited satisfactory physicochemical and in vitro release characteristics. Release data indicated a non-Fickian trend of drug release from the formulations. Based on the results, this study suggest that CIPRO loaded IPN microspheres were suitable for sustained release application. PMID:23987317

  7. The lowering effect of Gum Arabic on hyperlipidemia in Sudanese patients

    PubMed Central

    Mohamed, Rima E.; Gadour, Mohammed O.; Adam, Ishag

    2015-01-01

    Hyperlipidemia especially low density lipoprotein cholesterol (LDL-C) is a major risk factor for developing ischemic heart disease. Soluble dietary fiber has lipid lowering characteristics. Gum Arabic (GA) is 95% soluble fiber calculated on dry bases. The beneficial effect of GA on lipid profile needs further verification. A case–control study was conducted at Omdurman Hospital, Sudan to assess the effect of G A on serum lipids in patients with hyperlipidemia. Cases received a 20 mg tablet of atorvastatin /day plus 30 mg of GA for 4 weeks while the controls received atorvastatin only. Levels of lipids in serum were assessed according to conventional methods before and 1 month after the trial. There is no significant difference in the basic characteristics between the study and the control groups (55 patients in each arm of the study). While there was no significant difference in the levels of HDL, there was a significant reduction of the total cholesterol (25.9 vs. 7.8%, P < 0.001), triglyceride (38.2 vs. 2.9%, P < 0.001), and LDL (30.8 vs. 8.1%, P < 0.001) before and after the intervention in the study compared to the controls groups. PMID:26042049

  8. Utilization of gum tragacanth as bind enhancing agent in extended restructured mutton chops.

    PubMed

    Sharma, Heena; Sharma, B D; Talukder, S; Ramasamy, Giriprasad

    2015-03-01

    Use of extenders in meat products is not only health promoting but can also increase the economic worth of the products. Extension of the meat product is generally associated with poor binding and texture. Thus, the present study was envisaged to solve this problem by the incorporation of gum tragacanth (GT) as bind enhancing agent, used at three different levels viz., 0.1, 0.15 and 0.2 % in a pre standardized formulation of extended restructured mutton chops (ERMC), by replacing the lean meat. The products were subjected to analysis for physico-chemical, sensory and textural properties. There was no significant difference (P?>?0.05) in any of the physicochemical property parameters of product incorporated with different levels of GT except fat percent and shear force value. Mean scores for binding, texture and overall acceptability of ERMC incorporated with 0.1 % GT recorded significantly higher value (P?

  9. Post-meal perceivable satiety and subsequent energy intake with intake of partially hydrolysed guar gum.

    PubMed

    Rao, Theertham Pradyumna; Hayakawa, Mariko; Minami, Tadayasu; Ishihara, Noriyuki; Kapoor, Mahendra Parkash; Ohkubo, Tsutomu; Juneja, Lekh Raj; Wakabayashi, Kazuo

    2015-05-01

    Partially hydrolysed guar gum (PHGG), a soluble dietary fibre, has been shown to provide many health benefits. Previous studies had suggested that the combination of PHGG with protein provided a significant satiation effect on visual analogue scales (VAS). What was lacking was only the effect of administration of small doses of PHGG on post-meal satiation and subsequent energy intake. The objectives of the present investigations were to find the subjective perception of post-meal satiety with acute and long term administration of small amounts of PHGG alone with food, its effects on subsequent energy intake and the comparative effects among different types of soluble fibres. The following three separate studies were conducted: in study 1, healthy subjects (n 12) consumed PHGG along with breakfast, lunch and an evening snack; in study 2, healthy subjects (n 24) consumed 2 g of PHGG or dextrin along with yogurt as breakfast for 2 weeks; in study 3, healthy subjects (n 6) took 6 g each of either PHGG or indigestible dextrin or inulin along with lunch. In all the studies, various satiety parameters were measured on VAS before and after consumption of PHGG. The addition of PHGG showed significant (P< 0·05) acute (studies 1 and 3) and long-term (studies 1 and 2) satiety effects compared to the control and/or an equal amount of carbohydrate or other types of soluble fibre. Study 2 also indicated that the prolonged consumption of PHGG may significantly (P< 0·05) reduce energy intake from whole-day snacking. PHGG could be an ideal natural soluble fibre for delivering acute and long term satiety effects for comfortable appetite control. PMID:25851425

  10. Objects associated with low-mass star formation in the GUM nebula

    NASA Astrophysics Data System (ADS)

    Graham, J. A.

    1986-03-01

    The Gum nebula contains a number of small, dense molecular clouds, some of which are still producing stars of low mass. Observations are presented of three small nebulae and one peculiar emission line star which are located in or near the dust clouds Sandqvist 109 and 111. The three nebulae are each coincident with point sources in the IRAS catalog which, in each case, apparently mark the location of a very young star embedded within the dust cloud. Two nebulae, Re 4 and Re 5, were discovered in a survey by Reipurth. The third is the object HH 46, which belongs to the remarkable string of Herbig-Haro (HH) objects first described by Schwartz. A 15th mag star near the head of the Re 4 nebula is almost certainly a foreground object and is not connected with Re 4 itself. The spectrum of Re 4 shows emission lines characteristic of HH objects superposed on a very red continuum. Re 5 shows only a red continuum with a few absorption lines. Broad emission lines in HH 46 indicates a complex velocity pattern near the associated IRAS source. The principal peculiarity of the M-type emission line dwarf is a small, jet-like appendage, with a purely emission line spectrum. Attention is directed to the likelihood that star formation is being observed here under highly simplified circumstances. Such examples are likely to be especially amenable to the study both of the initial conditions for star birth and of the subsequent evolution of the resulting star.

  11. Cyclodextrin complexes of reduced bromonoscapine in guar gum microspheres enhance colonic drug delivery.

    PubMed

    Madan, Jitender; Gundala, Sushma R; Baruah, Bharat; Nagaraju, Mulpuri; Yates, Clayton; Turner, Timothy; Rangari, Vijay; Hamelberg, Donald; Reid, Michelle D; Aneja, Ritu

    2014-12-01

    Here, we report improved solubility and enhanced colonic delivery of reduced bromonoscapine (Red-Br-Nos), a cyclic ether brominated analogue of noscapine, upon encapsulation of its cyclodextrin (CD) complexes in bioresponsive guar gum microspheres (GGM). Phase-solubility analysis suggested that Red-Br-Nos complexed with ?-CD and methyl-?-CD in a 1:1 stoichiometry, with a stability constant (Kc) of 2.29 × 10(3) M(-1) and 4.27 × 10(3) M(-1). Fourier transforms infrared spectroscopy indicated entrance of an O-CH? or OCH?-C?H?-OCH? moiety of Red-Br-Nos in the ?-CD or methyl-?-CD cavity. Furthermore, the cage complex of Red-Br-Nos with ?-CD and methyl-?-CD was validated by several spectral techniques. Rotating frame Overhauser enhancement spectroscopy revealed that the Ha proton of the OCH?-C?H?-OCH? moiety was closer to the H? proton of ?-CD and the H? proton of the methyl-?-CD cavity. The solubility of Red-Br-Nos in phosphate buffer saline (PBS, pH ? 7.4) was improved by ?10.7-fold and ?21.2-fold when mixed with ?-CD and methyl-?-CD, respectively. This increase in solubility led to a favorable decline in the IC?? by ?2-fold and ?3-fold for Red-Br-Nos-?-CD-GGM and Red-Br-Nos-methyl-?-CD-GGM formulations respectively, compared to free Red-Br-Nos-?-CD and Red-Br-Nos-methyl-?-CD in human colon HT-29 cells. GGM-bearing drug complex formulations were found to be highly cytotoxic to the HT-29 cell line and further effective with simultaneous continuous release of Red-Br-Nos from microspheres. This is the first study to showing the preparation of drug-complex loaded GGMS for colon delivery of Red-Br-Nos that warrants preclinical assessment for the effective management of colon cancer. PMID:25350222

  12. Rheological and kinetic study of the ultrasonic degradation of locust bean gum in aqueous saline and salt-free solutions.

    PubMed

    Li, Ruoshi; Feke, Donald L

    2015-11-01

    The ultrasonic degradation of locust bean gum (LBG) in aqueous solutions has been studied at 25°C for ultrasonication times up to 120min. Although LBG is not a polyelectrolyte, the degradation extent and kinetics were found to be somewhat sensitive to the ionic conditions in solution, and this is attributed to changes in molecular conformation that can occur in different salt environments. Ultrasonic degradation was tracked by rheological measurements that lead to the determination of intrinsic viscosity for the LBG molecules. A kinetic model was also developed and successfully applied to characterize and predict the degradation results. PMID:26186852

  13. Plant regeneration from cell suspension-derived protoplasts of Phalaenopsis

    Microsoft Academic Search

    B. R. Shrestha; K. Tokuhara; M. Mii

    2007-01-01

    Protoplasts isolated from cell suspension culture of Phalaenopsis “Wataboushi” were cultured by (a) embedding in gellan gum-solidified hormone-free 1\\/2 New Dogashima medium (1\\/2 NDM) containing\\u000a 0.44 M sorbitol, 0.06 M sucrose and 0.1 g\\/l l-glutamine (standard method) and (b) beads method using beads of gellan gum or sodium alginate as the gelling agents which\\u000a were surrounded by liquid NDM. Although, the two beads methods

  14. Analysis of pentacyclic triterpenic acids from frankincense gum resins and related phytopharmaceuticals by high-performance liquid chromatography. Identification of lupeolic acid, a novel pentacyclic triterpene.

    PubMed

    Büchele, Berthold; Zugmaier, Waltraud; Simmet, Thomas

    2003-07-01

    An HPLC gradient method with photodiode array detection was developed for the simultaneous analysis of 12 different pentacyclic triterpenic acids in Indian and African frankincense gum resins as well as in related phytopharmaceuticals. The triterpenic acids were obtained by an exhaustive extraction procedure. Identification of the compounds was based on retention times, UV-spectra and add on technique with standards isolated from African frankincense. The method allows differentiation of frankincense of different origin and standardization of frankincense-based phytopharmaceuticals. Further, this is the first report identifying a novel pentacyclic triterpene, lupeolic acid, as a constituent of frankincense gum resins. PMID:12798161

  15. Budesonide-Loaded Guar Gum Microspheres for Colon Delivery: Preparation, Characterization and in Vitro/in Vivo Evaluation

    PubMed Central

    Liu, Ye; Zhou, Hong

    2015-01-01

    A novel budesonide (BUD) colon delivery release system was developed by using a natural polysaccharide, guar gum. The rigidity of the microspheres was induced by a chemical cross-linking method utilizing glutaraldehyde as the cross-linker. The mean particle size of the microspheres prepared was found to be 15.21 ± 1.32 µm. The drug loading and entrapment efficiency of the formulation were 17.78% ± 2.31% and 81.6% ± 5.42%, respectively. The microspheres were spherical in shape with a smooth surface, and the size was uniform. The in vitro release profiles indicated that the release of BUD from the microspheres exhibited a sustained release behavior. The model that fitted best for BUD released from the microspheres was the Higuchi kinetic model with a correlation coefficient r = 0.9993. A similar phenomenon was also observed in a pharmacokinetic study. The prolongation of the half-life (t1/2), enhanced residence time (mean residence time, MRT) and decreased total clearance (CL) indicated that BUD microspheres could prolong the acting time of BUD in vivo. In addition, BUD guar gum microspheres are thought to have the potential to maintain BUD concentration within target ranges for a long time, decreasing the side effects caused by concentration fluctuation, ensuring the efficiency of treatment and improving patient compliance by reducing dosing frequency. None of the severe signs, like the appearance of epithelial necrosis and the sloughing of epithelial cells, were detected. PMID:25629228

  16. Effect of NaCl Addition on Rheological Behaviors of Commercial Gum-Based Food Thickener Used for Dysphagia Diets

    PubMed Central

    Cho, Hyun-Moon; Yoo, Whachun; Yoo, Byoungseung

    2015-01-01

    Rheological properties of thickened fluids used for consumption by people with dysphagia (swallowing difficulty) are very sensitive to several factors, such as thickener type, temperature, pH, sugar, protein, and NaCl. In this study, steady and dynamic rheological properties of thickened water samples mixed with five commercial xanthan gum-based food thickeners (A~E) were studied in the presence of NaCl at different concentrations (0.3%, 0.6%, 0.9%, and 1.2%). The magnitudes of apparent viscosity (?a,50), consistency index (K), yield stress (?oc), and dynamic moduli (G? and G?) showed significant differences in rheological behaviors between thickened samples with various NaCl concentrations. Dynamic moduli values of all thickened samples, except for samples with thickener C, were much higher than those of the control (0% NaCl). All rheological parameter values (K, G?, and G?) in a thickener A were much higher than those in other thickeners. These results suggest that rheological properties of thickened samples containing NaCl are strongly affected by xanthan gum-NaCl interaction and depended on the type of thickener.

  17. Improving the physical and moisture barrier properties of Lepidium perfoliatum seed gum biodegradable film with stearic and palmitic acids.

    PubMed

    Seyedi, Samira; Koocheki, Arash; Mohebbi, Mohebbat; Zahedi, Younes

    2015-06-01

    Stearic and palmitic fatty acids (10%, 20% and 30%, W/W gum) were used to improve the barrier properties of Lepidium perfoliatum seed gum (LPSG) film. The impact of the incorporation of fatty acids into the film matrix was studied by investigating the physical, mechanical, and barrier properties of the films. Addition of stearic and palmitic fatty acids to LPSG films reduced their water vapor permeability (WVP), moisture content, water solubility and water adsorption. Increasing fatty acid concentration from 10% to 30%, reduced the elongation at break (EB). Lower values of tensile strength (TS) and elastic modulus (EM) were obtained in the presence of higher fatty acids concentrations. Incorporation of fatty acids led to production of opaque films and the opacity increased as function of fatty acids concentration. Results showed that moisture content, water solubility and WVP decreased as the chain length of fatty acid increased. Therefore, LPSG-fatty acids composite film could be used for packaging in which a low affinity toward water is needed. PMID:25795389

  18. Release kinetics of actives from chewing gums into saliva monitored by direct analysis in real time mass spectrometry.

    PubMed

    Jeckelmann, Nicolas; Haefliger, Olivier P

    2010-04-30

    Direct analysis in real time mass spectrometry (DART-MS) was used to monitor the release kinetics of a taste-refreshing compound from chewing gums into the saliva of subjects. A new DART-MS sample probe was designed which was about four times more sensitive than the current benchmark probe. This decreased the impact of the dilution of the saliva samples that was required to minimize ion suppression effects and make quantitative analyses without an internal standard possible. The new probe was also about three times more reproducible, which allowed quantitative measurements to be conducted manually without requiring the enhanced precision provided by an automatic sample positioner. The accuracy of analyses performed by DART-MS was verified by comparing the results obtained from saliva samples analyzed both by DART-MS and by a more classical liquid chromatography/mass spectrometry (LC/MS) method. This investigation showed good agreement between the two techniques. DART-MS could then be used to objectively demonstrate the efficiency of a granular carbohydrate-based delivery system to boost for a few minutes the release of a lipophilic flavor raw material with a high octanol/water partition coefficient, cyclohexanecarboxamide, N-ethyl-5-methyl-2-(1-methylethyl) (WS-3), from chewing gum into saliva. PMID:20301100

  19. Synthesis, characterization and swelling properties of guar gum-g-poly(sodium acrylate-co-styrene)/muscovite superabsorbent composites

    NASA Astrophysics Data System (ADS)

    Wang, Wenbo; Kang, Yuru; Wang, Aiqin

    2010-04-01

    A series of novel guar gum-g-poly(sodium acrylate-co-styrene)/muscovite (GG-g-P(NaA-co-St)/MVT) superabsorbent composites were prepared by free-radical grafting copolymerization of natural guar gum (GG), partially neutralized acrylic acid (NaA), styrene (St) and muscovite (MVT) using ammonium persulfate (APS) as the initiator and N,N-methylene-bis-acrylamide (MBA) as the crosslinker. Optical absorption spectra confirmed that NaA and St had been grafted onto the GG main chain and MVT participated in the polymerization reaction. The simultaneous introduction of St and MVT into the GG-g-PNaA matrix could clearly improve the surface morphologies of the composites, and MVT led to better dispersion in the polymeric matrix without agglomeration, as revealed by electron microscopy. The effects of St and MVT on the water absorption and swelling behavior in various saline solutions, aqueous solutions of hydrophilic organic solvents and surfactant solutions were investigated. Results indicated that the swelling rate and capabilities of the composites were markedly enhanced by the incorporation of the hydrophobic monomer St and inorganic MVT clay mineral. The superabsorbent composite showed a clearer deswelling characteristic in solutions of multivalent saline, acetone and ethanol, and cationic surfactant than that in the solutions of multivalent saline, methanol and anionic surfactant.

  20. Effects of antioxidants on the stability of ?-Carotene in O/W emulsions stabilized by Gum Arabic.

    PubMed

    Liu, Yuwei; Hou, Zhanqun; Yang, Jia; Gao, Yanxiang

    2015-06-01

    The potential of oil-in-water emulsions as a ?-carotene delivery system was examined in this study. Oil-in-water (O/W) emulsions containing ?-carotene were formed by gum arabic with ?-tocopherol, tertiary butyl hydroquinone (TBHQ) and ascorbyl palmitate, respectively. The influence of antioxidants on the chemical degradation of ?-carotene in gum arabic stabilized emulsions was investigated at 4, 25, 45 and 65 °C in the dark, respectively. An accelerated photo-oxidation test was carried out at 45 °C (450 W/m(2)). Moreover, ?-carotene degradation rate constants (k 1-value), activation energy (E a ) and decimal reduction time (D-value) were estimated to interpret the degradation kinetics. The impact of antioxidants on the thermal stability of ?-carotene in diluted emulsions was generally in the following order: ?-tocopherol?>?TBHQ?>?ascorbyl palmitate. ?-Tocopherol was found to be the most effective to the antioxidation of ?-carotene at the concentration of 0.10 wt% under light exposure. It was concluded that the stability of ?-carotene in oil-in-water emulsions could be improved by the presence of different antioxidants. PMID:26028711

  1. Action of Tumor-inhibitory Gum Tragacanth on Potassium Permeability of Ascites Tumor Cells and Partial Characterization of the Cytotoxic Componentl

    Microsoft Academic Search

    E. M. F. Roe; Honor Smyth; Eleanor Flahavan

    1972-01-01

    SUMMARY Electrolyte balance was examined in ascites tumor cells treated with the surface-combining mitotic inhibitor gum tragacanth. Potassium and sodium levels remained normal during treatment with physiological doses of the agent, thus precluding imbalance of these ions as an explanation of the tumor-inhibitory effect. Incorporation of amino acids into protein also remained unaffected. Washing and centrifugation of treated cells resulted

  2. Two new species of sympatric Fergusonina flies (Diptera: Fergusoninidae) from bud galls on high elevation snow gums (Eucalyptus pauciflora Sieb. ex Spreng. complex) in the Australian Alps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two species of Fergusonina Malloch fly, F. daviesae Nelson sp.n. and F. taylori Nelson sp.n. (Diptera: Fergusoninidae), are described from terminal leaf bud galls on high elevation snow gums (Eucalyptus pauciflora complex) in the Australian Alps. These species occur in sympatry at the six locations...

  3. Partially hydrolyzed guar gum affects the expression of genes involved in host defense functions and cholesterol absorption in colonic mucosa of db/db male mice

    PubMed Central

    Yasukawa, Zenta; Naito, Yuji; Takagi, Tomohisa; Mizushima, Katsura; Tokunaga, Makoto; Ishihara, Noriyuki; R. Juneja, Lekh; Yoshikawa, Toshikazu

    2012-01-01

    Biomedical evidence in the last 20 years has shown that the consumption of partially hydrolyzed guar gum may influence lipid and/or carbohydrate metabolism at many levels. Since intestine represents the first interface to interact with dietary partially hydrolyzed guar gum in vivo, we evaluated gene expression profiles in small intestinal mucosa of db/db mice fed with partially hydrolyzed guar gum in an effort to delineate its effect on the small intestine. DNA microarray and real-time PCR analyses were performed to evaluate the gene expression profiles in mice small intestinal mucosa. Among the 28,853 transcripts represented on the GeneChip® microarray, no more than 20 genes exhibited up- or down-regulation by 1.5-fold or more after four weeks following partially hydrolyzed guar gum consumption. No adverse effects were apparent. We detected up- or down-regulation of some genes known to be involved in host defense functions and cholesterol absorption. PMID:22798710

  4. Long term ingestion of a preload containing fructo-oligosaccharide or guar gum decreases fat mass but not food intake in mice.

    PubMed

    Hadri, Zouheyr; Chaumontet, Catherine; Fromentin, Gilles; Even, Patrick C; Darcel, Nicolas; Bouras, Abdelkader Dilmi; Tomé, Daniel; Rasoamanana, Rojo

    2015-08-01

    Fermentable dietary fibre such as fructo-oligosaccharide and viscous dietary fibers such as guar gum and alginate affect energy homeostasis. The goal of this study was to compare the impact of long term intake of these three dietary fibers on food intake, meal pattern, body weight and fat accumulation in mice. Over a period of 3weeks, the mice were fed daily with a preload containing 32mg of fructo-oligosaccharide or alginate or 13mg of guar gum. Food intake and body weight were monitored weekly, while meal patterns, adiposity and the expression of hypothalamic neuropeptide genes were evaluated at the end of the study period. The 3 dietary fibers produced a similar decrease in total daily food intake (14 to 22%) at the end of the first week, and this effect disappeared over time. The 3 dietary fibers induced a slight variation in satiation parameters. Body weight and expression of hypothalamic neuropeptide genes were not affected by any of the treatment. Preload of fructo-oligosaccharide and guar gum induced a similar and substantial decrease in the development of adiposity (17% and 14%, respectively), while alginate had no effect. Our results demonstrate mainly that the inhibitory effect of dietary fiber on food intake is lost over time, and that guar gum limits fat storage. PMID:25914171

  5. Gum and resin resources from some Acacia, Boswellia and Commiphora species and their economic contributions in Liban, south-east Ethiopia

    Microsoft Academic Search

    Mulugeta Lemenih; Tarekegn Abebe; Mats Olsson

    2003-01-01

    Oleo-gum resins, hardened resinous plant exudates obtained from some Acacia, Boswellia and Commiphora species in the lowlands of Ethiopia, have been traded for centuries both on the international and domestic markets. However, their economic contribution to the rural households is little documented. A reconnaissance survey was carried out in Liban, one of the administrative zones in the Ethiopian Somali National

  6. Biofilms on submerged River Red Gum ( Eucalyptus camaldulensis Dehnh. Myrtaceae) wood in billabongs: an analysis of bacterial assemblages using phospholipid profiles

    Microsoft Academic Search

    Oliver Scholz; Paul I. Boon

    1993-01-01

    Biofilms were allowed to develop on wooden slides of the River Red Gum (Eucalyptus camaldulensis Dehnh., Myrtaceae) submerged in two billabongs of south-eastern Australia. The slides were placed in the photic zone and the aphotic zone, and the biofilms sampled after eight week's growth over the summer of 1989–1990 and winter of 1990. Bacterial numbers, estimated with epifluorescence microscopy, ranged

  7. Low-fat sodium-reduced sausages: Effect of the interaction between locust bean gum, potato starch and ?-carrageenan by a mixture design approach

    Microsoft Academic Search

    Elizabeth García-García; Alfonso Totosaus

    2008-01-01

    A mixture design approach was used to evaluate interactions between potato starch, locust bean gum and ?-carrageenan and their effect on cooking yield, expressible moisture, texture and color in low-fat sodium-reduced sausages formulated with potassium and calcium chloride. Starch had a notable influence on cooking yield and texture, increasing product hardness and resilience as starch proportion increased. The added salt

  8. Pathways to Health: A Cluster Randomized Trial of Nicotine Gum and Motivational Interviewing for Smoking Cessation in Low-Income Housing

    ERIC Educational Resources Information Center

    Okuyemi, Kolawole S.; James, Aimee S.; Mayo, Matthew S.; Nollen, Nicole; Catley, Delwyn; Choi, Won S.; Ahluwalia, Jasjit S.

    2007-01-01

    Despite high smoking rates among those living in poverty, few cessation studies are conducted in these populations. This cluster-randomized trial tested nicotine gum plus motivational interviewing (MI) for smoking cessation in 20 low-income housing developments (HDs). Intervention participants (10 HDs, n = 66) received educational materials, 8…

  9. Application of guar gum biopolymer in the prescription of tablets with sodium ibuprofen--quality tests and pharmaceutical availability in vitro.

    PubMed

    Berner-Strzelczyk, Aneta; Ko?odziejska, Justyna; Zgoda, Marian Miko?aj

    2006-01-01

    The increasing interest of the technology of drug form in natural biopolymers has become the reason for undertaking investigations on the possibility of guar gum application in the prescription of oral solid form of a drug. Alternative compositions and technology of the production of tablets of regulated in time sodium ibuprofen release were worked out for children. Two series of tablets were prepared with guar gum (5 and 10% content) and a series without the biopolymer. The tablet mass in each case contained keryostatic sorbitol and bioadhesive polyvinylpyrrolidone. All tablets were tested as regards the quality of production, compliance with the requirements of Polish Pharmacopoeia VI and potential therapeutic usefulness, manifestation of which is pharmaceutical availability of the therapeutic agent (sodium ibuprofen). The tests demonstrated that the produced tablets with sodium ibuprofen have proper physicochemical properties, in compliance with Polish Pharmacopoeia VI requirements. Application of biopolymer of guar gum type as adjuvant substance contributes to the improvement of the tablet hardness parameters and prevents technological problems (lining mixture of powders to tableting machine punch). The designed tablets demonstrate proper pharmaceutical availability of over 80%. Introduction of guar gum into their prescription prolonged their disintegration time and the rate of sodium ibuprofen release, which predisposes the produced form of a drug to have the function of a tablet with slowed-down release. PMID:17402228

  10. High-Fiber Diet Supplementation in Patients with Irritable Bowel Syndrome (IBS): A Multicenter, Randomized, Open Trial Comparison Between Wheat Bran Diet and Partially Hydrolyzed Guar Gum (PHGG)

    Microsoft Academic Search

    G. C. Parisi; M. Zilli; M. P. Miani; M. Carrara; E. Bottona; G. Verdianelli; G. Battaglia; S. Desideri; A. Faedo; C. Marzolino; A. Tonon; M. Ermani; G. Leandro

    2002-01-01

    High-fiber diet supplementation is commonly used in IBS, although it poses several management problems. Partially hydrolyzed guar gum (PHGG) has shown beneficial effects in animal and human studies, but its potential role in IBS symptom relief has not been evaluated yet. We investigated PHGG in IBS patients and compared it to a wheat bran diet. Abdominal pain, bowel habits, and

  11. Occurrence of Dental Decay in Children after Maternal Consumption of Xylitol Chewing Gum, a Follow-up from 0 to 5 Years of Age

    Microsoft Academic Search

    P. Isokangas; E. Soderling; K. Pienihakkinen; P. Alanen

    2000-01-01

    Studies have shown that prevention of mutans streptococci (MS) colonization in early childhood can lead to prevention of dental decay. In the microbiological part of the present study in Ylivieska, Finland, with 195 mothers with high salivary MS levels, regular maternal use of xylitol chewing gum resulted in a statistically significant reduction in MS colonization in their children's teeth at

  12. Oral administration of chios mastic gum or extracts in mice: quantification of triterpenic acids by liquid chromatography-tandem mass spectrometry.

    PubMed

    Lemonakis, Nikolaos; Magiatis, Prokopios; Kostomitsopoulos, Nikolaos; Skaltsounis, Alexios-Leandros; Tamvakopoulos, Constantin

    2011-11-01

    Chios mastic gum, the resin obtained as an exudate from the trunk and branches of Pistacia lentiscus L var. chia, is used extensively as a constituent of herbal drugs or functional foods. The oral absorption of its major constituents still remains unclear. In the context of identifying the features of mastic gum that are responsible for either therapeutic effects or effects of nutritional value, a methodology based on high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry (MS/MS) was developed and applied for the quantification of mastic gum triterpenic acids, 24Z-isomasticadienonic acid (IMNA), and 24Z-isomasticadienolic acid (IMLA) in mouse plasma. The specific compounds were selected based on their biological activity and potential against Helicobacter pylori. Concentrations were determined simultaneously in mouse plasma after oral administration of mastic gum or total mastic extract without polymer (TMEWP) in order to evaluate the role of the natural polymer, poly-?-myrcene, in the absorption process. Following TMEWP administration in mice, circulating IMNA and IMLA plasma levels were significantly higher (approximately 10-fold) in comparison to IMNA and IMLA plasma levels following total mastic gum administration (CMG), suggesting that the polymer plays a critical role in the absorption process. More specifically following TMEWP administration, Cmax plasma values were 3300?±?859?ng/mL for IMNA and 163?±?58?ng/mL for IMLA. In comparison, following CMG administration, Cmax plasma values were 329?±?57?ng/mL for IMNA and 28?±?8?ng/mL for IMLA. The methodological approaches presented in this study, along with the findings, offer valuable information on the availability of bioactive components following ingestion of mastic and facilitate the uses of mastic either as an ingredient of functional foods or as a herbal drug. PMID:21870323

  13. A Randomized Clinical Trial Study: Anti-Oxidant, Anti-hyperglycemic and Anti-Hyperlipidemic Effects of Olibanum Gum in Type 2 Diabetic Patients.

    PubMed

    Azadmehr, Abbas; Ziaee, Amir; Ghanei, Laleh; Fallah Huseini, Hassan; Hajiaghaee, Reza; Tavakoli-Far, Bahareh; Kordafshari, Gholamreza

    2014-01-01

    Diabetes is a common metabolic disease in the world that has many adverse effects. Olibanum gum resin (from trees of the genus Boswellia) has traditionally been used in the treatment of various diseases such as diabetes. The aim of this study was the comparison of Olibanum gum resin effect with placebo on the treatment of type 2 diabetes. Inclusion criteria was diabetic patients with fasting blood sugar (FBS) =140-200 mg/dL. This study has been designed as double-blined clinical trial on 71 patients with type 2 diabetes and the patients randomly were divided to interventional and placebo groups. The patients on standard anti-diabetic therapy (metformin) treated with Olibanum gum resin (400 mg caps) and placebo tow times per day for 12 weeks, respectively. At the end of the twelfth week, the FBS, HbA1c, Insulin, total Cholesterol (Chol), LDL, Triglyceride (TG), HDL and other parameters were measured. The Olibanum gum resin lowered the FBS, HbA1c, Insulin, Chol, LDL and TG levels significantly (p < 0.001, p < 0.001, p <0.001, p = 0.003, p < 0.001 and p < 0.001, respectively) without any significant effects on the other blood lipid levels and liver/kidney function tests (p > 0.05) compared with the placebo at the endpoint. Moreover, this plant showed anti-oxidant effect and also no adverse effects were reported. The results suggest that Olibanum gum resin could be used as a safe anti-oxidant, anti-hyperglycemic and anti-hyperlipidemic agent for type 2 diabetic patients. PMID:25276202

  14. A Randomized Clinical Trial Study: Anti-Oxidant, Anti-hyperglycemic and Anti-Hyperlipidemic Effects of Olibanum Gum in Type 2 Diabetic Patients

    PubMed Central

    Azadmehr, Abbas; Ziaee, Amir; Ghanei, Laleh; Fallah Huseini, Hassan; Hajiaghaee, Reza; Tavakoli-far, Bahareh; Kordafshari, Gholamreza

    2014-01-01

    Diabetes is a common metabolic disease in the world that has many adverse effects. Olibanum gum resin (from trees of the genus Boswellia) has traditionally been used in the treatment of various diseases such as diabetes. The aim of this study was the comparison of Olibanum gum resin effect with placebo on the treatment of type 2 diabetes. Inclusion criteria was diabetic patients with fasting blood sugar (FBS) =140-200 mg/dL. This study has been designed as double-blined clinical trial on 71 patients with type 2 diabetes and the patients randomly were divided to interventional and placebo groups. The patients on standard anti-diabetic therapy (metformin) treated with Olibanum gum resin (400 mg caps) and placebo tow times per day for 12 weeks, respectively. At the end of the twelfth week, the FBS, HbA1c, Insulin, total Cholesterol (Chol), LDL, Triglyceride (TG), HDL and other parameters were measured. The Olibanum gum resin lowered the FBS, HbA1c, Insulin, Chol, LDL and TG levels significantly (p < 0.001, p < 0.001, p <0.001, p = 0.003, p < 0.001 and p < 0.001, respectively) without any significant effects on the other blood lipid levels and liver/kidney function tests (p > 0.05) compared with the placebo at the endpoint. Moreover, this plant showed anti-oxidant effect and also no adverse effects were reported. The results suggest that Olibanum gum resin could be used as a safe anti-oxidant, anti-hyperglycemic and anti-hyperlipidemic agent for type 2 diabetic patients. PMID:25276202

  15. Kinetic analysis of growth and xanthan gum production with Xanthomonas campestris on sucrose, using sequentially consumed nitrogen sources.

    PubMed

    Letisse, F; Chevallereau, P; Simon, J L; Lindley, N D

    2001-05-01

    A batch fermentation strategy using Xanthomonas campestris ATCC 13951 for xanthan gum production has been established in which all essential medium components are supplied at the onset. This has been achieved using sucrose as sole sugar feedstock. Sequential consumption of nitrogen sources (soybean hydrolysates, ammonium and nitrate salts) was observed to facilitate the further optimisation of the medium. Biomass accumulation was limited by phosphate availability. Xanthan yields of more than 60% (grams of xanthan per gram of sugar) have been obtained with constant acetyl content. However, pyruvyl substitution decreased as the growth rate declined, due to the metabolic constraints specific to phosphate depletion. High rates of carbon conversion into xanthan were observed throughout the culture and the ATP/ADP ratio was not affected by the decline in the specific growth rate. PMID:11398920

  16. Development of a phenomenological modeling approach for prediction of growth and xanthan gum production using Xanthomonas campestris.

    PubMed

    Letisse, Fabien; Lindley, Nic D; Roux, Gilles

    2003-01-01

    An unstructured kinetic model for xanthan production is described and fitted to experimental data obtained in a stirred batch reactor. The culture medium was composed of several nitrogen sources (soybean hydrolysates, ammonium and nitrate salts) consumed sequentially. The model proposed is able to describe this sequential consumption of nitrogen sources, the consumption of inorganic phosphate and carbon, the evolution of biomass, and production of xanthan. The parameter estimation has been performed by fitting the kinetic model in differential form to experimental data. Runs of the model for simulating xanthan gum production as a function of the initial concentration of inorganic phosphate have shown the positive effect of phosphate limitation on xanthan yield, though diminishing rates of production. The model was used to predict the kinetic parameters for a medium containing a 2-fold lower initial phosphate concentration. When tested experimentally, the measured fermentation parameters were in close agreement with the predicted model values, demonstrating the validity of the model. PMID:12790645

  17. Effects of mesquite gum-candelilla wax based edible coatings on the quality of guava fruit (Psidium guajava L.)

    NASA Astrophysics Data System (ADS)

    Tomás, S. A.; Bosquez-Molina, E.; Stolik, S.; Sánchez, F.

    2005-06-01

    The ability of composite edible coatings to preserve the quality of guava fruit (Psidium guajava L.) at 20ºC was studied for a period of 15 days. The edible coatings were formulated with candelilla wax blended with white mineral oil as the lipid phase and mesquite gum as the structural material. The use of edible coatings prolonged the shelf life of treated fruits by retarding ethylene emission and enhancing texture as compared to control samples. At the sixth day, the ethylene produced by the control samples was fivefold higher than the ethylene produced by the coated samples. In addition, the physiological weight loss of coated fruits was nearly 30% lower than the control samples.

  18. A non-adhesive hybrid scaffold from gelatin and gum Arabic as packed bed matrix for hepatocyte perfusion culture.

    PubMed

    Sarika, P R; Sidhy Viha, C V; Sajin Raj, R G; Nirmala, Rachel James; Anil Kumar, P R

    2015-01-01

    Development of liver support systems has become one of the most investigated areas for the last 50 years because of the shortage of donor organs for orthotopic liver transplantations. Bioartificial liver (BAL) device is one of the alternatives for liver failure which provides a curing method and support patients to recover from certain liver failure diseases. The biological compartment of BAL is called the bioreactor where functionally active hepatocytes are maintained to support the liver specific functions. We have developed a packed bed bioreactor with a cytocompatible, polysaccharide-protein hybrid scaffold. The scaffold prepared from gelatin and gum Arabic acts as a packed bed matrix for hepatocyte culture. Quantitative evaluation of the hepatocytes cultured using packed bed bioreactor demonstrated that cells maintained liver specific functions like albumin and urea synthesis for seven days. These results indicated that the system can be scaled up to form the biological component of a bioartificial liver. PMID:25491996

  19. Formation and stabilization of nanoemulsion-based vitamin E delivery systems using natural biopolymers: Whey protein isolate and gum arabic.

    PubMed

    Ozturk, Bengu; Argin, Sanem; Ozilgen, Mustafa; McClements, David Julian

    2015-12-01

    Natural biopolymers, whey protein isolate (WPI) and gum arabic (GA), were used to fabricate emulsion-based delivery systems for vitamin E-acetate. Stable delivery systems could be formed when vitamin E-acetate was mixed with sufficient orange oil prior to high pressure homogenization. WPI (d32=0.11?m, 1% emulsifier) was better than GA (d32=0.38?m, 10% emulsifier) at producing small droplets at low emulsifier concentrations. However, WPI-stabilized nanoemulsions were unstable to flocculation near the protein isoelectric point (pH 5.0), at high ionic strength (>100mM), and at elevated temperatures (>60°C), whereas GA-stabilized emulsions were stable. This difference was attributed to differences in emulsifier stabilization mechanisms: WPI by electrostatic repulsion; GA by steric repulsion. These results provide useful information about the emulsifying and stabilizing capacities of natural biopolymers for forming food-grade vitamin-enriched delivery systems. PMID:26041190

  20. Isolation, analysis and antimicrobial activity of the acidic fractions of Mastic, Kurdica, Mutica and Cabolica gums from genus Pistacia.

    PubMed

    Sharifi, Mohammad Sharif; Hazell, Stuart Loyd

    2012-01-01

    The chemical entities of Mastic, Kurdica, Mutica and Cabolica gums from genus Pistacia have been isolated and characterised by GC-Mass Spectrometry, High Performance Liquid Chromatography and Column Chromatography. These chemical entities were screened for anti-microbial activities against nine strains of Helicobacter pylori and some other Gram-negative and Gram-positive bacteria. The most bioactive components were structurally analysed. These components mimic steroid compounds, in particular, the known antibiotic Fusidic acid.  Some of these chemical entities have produced promising data that could lead to the development of a novel class of antimicrobial agents that may have application in the treatment of infectious disease. Kill kinetics have been also performed, and the produced data were evaluated by Generalized Multiplicative Analysis Of Variance (GEMANOVA) for the bactericidal and bacteriostatic activities which can be clinically significant. The isolated components were all bactericidal. PMID:22980113

  1. Physical, chemical, and histologic changes in dentin caries lesions of primary teeth induced by regular use of polyol chewing gums.

    PubMed

    Mäkinen, K K; Chiego, D J; Allen, P; Bennett, C; Isotupa, K P; Tiekso, J; Mäkinen, P L

    1998-06-01

    A previous clinical trial showed that long-term use of saliva-stimulating polyol (xylitol and sorbitol) chewing gums was associated with arrest of dental caries in young subjects. After a 20-22-month intervention (when the subjects were 8 years old), a total of 23 primary teeth with extensive dentin caries lesions whose surface in clinical examination was found to be totally rehardened (remineralized) could be removed because the teeth were near their physiologic exfoliation time. These teeth were subjected to histologic, microhardness, and electron microscopic tests. The majority of the specimens had been remineralized from the surface by a non-cellular-mediated process within the remaining collapsed, organic extracellular matrix associated with the remaining dentinal surface. Many of the underlying dentinal tubules were filled with a matrix that had been subsequently mineralized. Dental microanalyses showed that the topmost (outer) 20-microm-thick rehardened layer of the lesions exhibited the highest Ca:P ratio, which leveled off at a depth of approximately 150 microm. The rehardened surface layer (normally <0.1 mm in thickness) was significantly (P < 0.001) harder than sound dentin and nearly as hard as sound enamel. Although the main source of the mineral present in the rehardened layer was most likely of salivary origin, some extracellular remineralization was probably mediated by odontoblasts. The results complete the dinical diagnoses of the original trial and suggest that regular use of polyol chewing gums may induce changes in dentin caries lesions, which in histologic and physiochemical studies show typical characteristics of rehardening and mineralization. PMID:9688223

  2. Effect of Boswellia serrata gum resin on the morphology of hippocampal CA1 pyramidal cells in aged rat.

    PubMed

    Hosseini-sharifabad, Mohammad; Esfandiari, Ebrahim

    2015-01-01

    Experimental evidence indicates that administration of Boswellia resin, known as olibanum or Frankincense, increases memory power. It is reported that beta boswellic acid, the major component of Boswellia serrata gum resin, could enhance neurite outgrowth and branching in hippocampal neurons. We therefore studied whether Boswellia treatment produces morphological changes in the superior region of cornu ammonis (CA1) in aged rats. Sixteen male Wistar rats, 24 months of age, were randomly divided in experimental and control groups. The experimental group was orally administered Boswellia serrata gum resin (100 mg/kg per day for 8 weeks) and the control group received a similar volume of water. The Cavalieri principle was employed to estimate the volumes of CA1 hippocampal field, and a quantitative Golgi study was used to analysis of dendritic arborizations of CA1 pyramidal cells. Comparisons revealed that Boswellia-treated aged rats had greater volumes than control animals in stratum pyramidale and stratum radiatum lacunosum-moleculare. The neurons of CA1 in experimental rats had more dendritic segments (40.25 ± 4.20) than controls (30.9 ± 4.55), P = 0.001. The total dendritic length of CA1 neurons was approximately 20 % larger in the experimental group compared to control. Results also indicated that the aged rats treated with Boswellia resin had more numerical branching density in the apical dendrites of CA1 pyramidal neurons. The results of the present study show that long-term administration of Boswellia resin can attenuate age-related dendritic regression in CA1 pyramidal cells in rat hippocampus. PMID:24515442

  3. Antileishmanial activity of Ferula assa-foetida oleo gum resin against Leishmania major: An in vitro study

    PubMed Central

    Bafghi, Ali Fatahi; Bagheri, Seyyed Majid; Hejazian, Seyed Hassan

    2014-01-01

    Background: In Ayurveda, asafetida is introduced as a valuable remedy for flatulence, hysteria, nervous disorders, whooping cough, pneumonia and bronchitis in children and also considered as an aphrodisiac agent. Presently, Leishmaniasis is common in most countries of the world and is a serious health problem in the world. Some plant medicines and natural products have a new candidate for treatment of leishmaniasis. Objective: This study was designed to evaluate Ferula assa-foetida oleo gum resin (asafetida) on mortality and morbidity Leishmania major in vitro. Materials and Methods: Mostigotes were isolated from mice spleens and then transformed to promastigotes in Novy-Nicolle-Mac Neal (NNN medium supplemented with penicillin (100 U/ml), streptomycin (100 ?g/ml) and 20% heat-inactivated fetal calf serum (FCS) at 25°C. A fixed initial density of the parasites was transferred to screw-capped vials containing 5 ml of RPMI1640 media to which different concentrations of 2.5, 5, 10 and 20 ?g asafetida were added and each concentration was done in triplicates. Each run also included control. The mortality of parasitoids was measured by the slide and the enzyme-linked immunosorbent assay (ELISA) methods. Results: After 72 h, asafetida inhibited growth of parasites in all doses in stationary and logarithmic phases. The ELISA measurement suggested that the viability of parasites significantly decreased after 48h (P < 0.05). Conclusion: The results show that asafetida could prevent from growth and viability of parasites and this oleo gum resin can be useful for treatment of leishmaniasis. PMID:25624696

  4. Preparation and Characterization of Selenium Incorporated Guar Gum Nanoparticle and Its Interaction with H9c2 Cells

    PubMed Central

    Soumya, Rema Sreenivasan; Vineetha, Vadavanath Prabhakaran; Reshma, Premachandran Latha; Raghu, Kozhiparambil Gopalan

    2013-01-01

    This study deals with the preparation and characterization of selenium incorporated guar gum nanoparticle (SGG), and its effect on H9c2 cardiomyoblast. Herein, nanoprecipitation techniques had been employed for the preparation of SGG nanoparticle. The prepared nanoparticle had been subjected to various types of analytical techniques like transmission electron microscopy (TEM), X-ray diffraction (XRD) and particle size analysis to confirm the characteristics of nanoparticle as well as for selenium incorporation. Physical characterization of nanoparticle showed that the size of nanoparticles increase upto ?69–173 nm upon selenium incorporation from ?41–132 nm. Then the prepared nanoparticles were evaluated for its effect on H9c2 cells. In this regard, the effect of nanoparticle on various vital parameters of H9c2 cells was studied. Parameters like cell viability, uptake of selenium incorporated guar gum nanoparticle by the cells, effect of SGG on DNA integrity, apoptosis, reactive oxygen species generation, alteration in transmembrane potential of mitochondria and cytoskeletal integrity had been investigated. Viability results showed that up to 25 nM of SGG was safe (10.31%) but beyond that it induces cytotoxicity. Cellular uptake of selenium showed that cell permeability for SGG is significantly high compared to normal selenium (7.2 nM of selenium for 25 nM SGG compared with 5.2 nM selenium for 25 nM sodium selenite). There was no apoptosis with SGG and also it protects DNA from hydroxyl radical induced breakage. Likewise no adverse effect on mitochondria and cytoskeleton was observed for 25 nM of SGG. Overall results reveal that SGG is highly suitable for biomedical research application. PMID:24098647

  5. Enhancement of preneoplastic lesion yield by Chios Mastic Gum in a rat liver medium-term carcinogenesis bioassay

    SciTech Connect

    Doi, Kenichiro [Department of Pathology, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585 (Japan)], E-mail: kenchan@med.osaka-cu.ac.jp; Wei, Min; Kitano, Mitsuaki; Uematsu, Naomi; Inoue, Masayo [Department of Pathology, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585 (Japan); Wanibuchi, Hideki [Department of Pathology, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585 (Japan)], E-mail: wani@med.osaka-cu.ac.jp

    2009-01-01

    The mastic (Pistacia lentiscus var. chia) tree is native throughout the Mediterranean region and has long proved a source of food additives and medical treatments. To investigate the modifying effects of Chios Mastic Gum on rat liver carcinogenesis, 6-week-old male F344 rats were subjected to the established rat liver medium-term carcinogenesis bioassay (Ito-test). At the commencement, rats (groups 1-4) were intraperitoneally injected with 200 mg/kg body weight of diethylnitrosamine (DEN). After two weeks, mastic was added to CRF (Charles River Formula)-1 powdered basal diet at doses of 0, 0.01, 0.1 and 1% in groups 1-4, respectively. At week 3, all rats were underwent two-thirds partial hepatectomy. The experiment was terminated at week 8. As results show, liver weights were significantly increased in a mastic dose-dependent manner among groups 1-4. The numbers (/cm{sup 2}) and the areas (mm{sup 2}/cm{sup 2}) of glutathione S-transferase placental form (GST-P)-positive cell foci ({>=} 0.2 mm in diameter) were significantly increased in the DEN-1% group compared to the DEN-alone group, along with the average areas per foci and larger-sized foci ({>=} 0.4 mm). 5-Bromo-2'-deoxyuridine (BrdU) + GST-P double-immunohistochemistry showed the highest BrdU-labeling indices within GST-P foci in the DEN-1% group. 8-hydroxydeoxyguanosine (8-OHdG) levels in liver DNA did not vary, while real-time quantitative polymerase chain reaction (PCR) analysis of livers revealed many up- or down-regulated genes in the DEN-1% group. In conclusion, this is the first report to display a promotion potential of Chios Mastic Gum on the formation of preneoplastic lesions in the established rat liver medium-term carcinogenesis bioassay.

  6. Mechanical and optical characterization of gelled matrices during storage.

    PubMed

    Lorenzo, Gabriel; Zaritzky, Noemí; Califano, Alicia

    2015-03-01

    The effect of composition and storage time on the rheological and optical attributes of multi-component gels containing locust bean gum (LBG), low acyl (LAG) and high acyl (HAG) gellan gums, was determined using three-component mixture design. The generalized Maxwell model was used to fit experimental rheological data. Mechanical and relaxation spectra of gelled systems were determined by the type of gellan gum used, except LBG alone which behaved as a diluted gum dispersion. Storage time dependence of the gels was analyzed using the rubber elasticity theory and to determine changes in network mesh size the equivalent network approach was applied. Destabilization kinetic was obtained from light scattering results; increasing LAG content improved the long-term stability of the matrices. Almost every formulation exhibited an increment in both moduli during the first 10 days remaining practically constant thereafter or until they broke (binary mixtures with LBG); gels with HAG/LBG mixtures were the least stable. PMID:25498706

  7. Plant regeneration from mesophyll protoplasts of lisianthus (Eustoma grandiflorum) by adding activated charcoal into protoplast culture medium

    Microsoft Academic Search

    Hisato Kunitake; Toshiki Nakashima; Kinya Mori; Masanobu Tanaka; Masahiro Mii

    1995-01-01

    Plant regeneration from isolated protoplasts of 8 cultivars of lisianthus, Eustoma grandiflorum (Griseb.) Schinners, has been established by using activated charcoal. Protoplasts were isolated from lisianthus leaves grown in vitro and started to divide within 3–4 days of culture, but successful colony formation was only achieved by adding gellan gum blocks containing 1% (w\\/v) activated charcoal immediately after culture. Colonies

  8. Printed hydrogel materials

    Microsoft Academic Search

    Don McCallum; Cameron Ferris; Paul Calvert; Gordon Wallace; Marc in het Panhuis

    2010-01-01

    An inkjet printer has been developed for printing hydrogel materials. The printer uses two peizo industrial printheads to print out combinations of cationic and anionic polymers, which then form gels on a substrate in a clear demonstration of reactive printing. The synthetic polymers poly- diallyl-dimethyl ammonium chloride and polystyrene sulfonate, and the naturally occurring polymers, alginate, chitosan and gellan gum

  9. Antimicrobial activities of tapioca starch\\/decolorized hsian-tsao leaf gum coatings containing green tea extracts in fruit-based salads, romaine hearts and pork slices

    Microsoft Academic Search

    Po-En Chiu; Lih-Shiuh Lai

    2010-01-01

    The antimicrobial activities of edible coatings based on a tapioca starch\\/decolorized hsian-tsao leaf gum (dHG) matrix with various green tea extracts (GTEs) were evaluated. Its effect on the shelf-life extension of fruit-based salads, romaine hearts, and pork slices were investigated as well. Three types of GTEs from hot water (80°C) (W), 40% (E4) and 80% (E8) ethanol were prepared. It

  10. Microwave initiated synthesis of polyacrylamide grafted guar gum (GG-g-PAM)—Characterizations and application as matrix for controlled release of 5-amino salicylic acid

    Microsoft Academic Search

    Gautam Sen; Sumit Mishra; Usha Jha; Sagar Pal

    2010-01-01

    This paper details the study of applicability of microwave initiated synthesized polyacrylamide grafted guar gum (GG-g-PAM) as matrix for controlled release of 5-amino salicylic acid (a drug used for the treatment of ulcerative colitis). In vitro release of this drug from various grades of GG-g-PAM has been studied by USP dissolution method (paddle type). The effect of percentage grafting on

  11. Effects of nicotine chewing gum on a real-life motor task: a kinematic analysis of handwriting movements in smokers and non-smokers

    Microsoft Academic Search

    Oliver Tucha; Klaus W. Lange

    2004-01-01

    Rationale In laboratory tasks nicotine has consistently been shown to improve psychomotor performance. Objectives The aim of the present experiment was to assess the effects of nicotine on a skilled task of everyday life in smoking and non-smoking healthy adults. Methods Assessment of handwriting movements of 38 non-deprived smokers and 38 non-smokers was performed following the chewing of gum containing

  12. Correlation, alteration, and origin of hydrocarbons in the GCA, Bahar, and Gum Adasi fields, western South Caspian Basin: geochemical and multivariate statistical assessments

    Microsoft Academic Search

    Kadir Gürgey

    2003-01-01

    Geochemical as well as multivariate statistical analyses (PCA) were carried out on 20 crude oil samples from ‘Middle’ Pliocene Production Series (MPPS) of Guneshli-Chirag-Azeri (GCA), Bahar, and Gum Adasi fields in the western South Caspian Basin (SCB). PCA analysis employed to source-specific biomarkers distinguishes the oils into two types one being divided into two sub-types; Type 1 (GCA oils), Type

  13. Purification and characterization of two alpha-galactosidases associated with catabolism of guar gum and other alpha-galactosides by Bacteroides ovatus.

    PubMed Central

    Gherardini, F; Babcock, M; Salyers, A A

    1985-01-01

    When Bacteroides ovatus is grown on guar gum, a galactomannan, it produces alpha-galactosidase I which is different from alpha-galactosidase II which it produces when grown on galactose, melibiose, raffinose, or stachyose. We have purified both of these enzymes to apparent homogeneity. Both enzymes appear to be trimers and have similar pH optima (5.9 to 6.4 for alpha-galactosidase I, 6.3 to 6.5 for alpha-galactosidase II). However, alpha-galactosidase I has a pI of 5.6 and a monomeric molecular weight of 85,000, whereas alpha-galactosidase II has a pI of 6.9 and a monomeric molecular weight of 80,500. alpha-Galactosidase I has a lower affinity for melibiose, raffinose, and stachyose (Km values of 20.8, 98.1, and 8.5 mM, respectively) than does alpha-galactosidase II (Km values of 2.3, 5.9, and 0.3 mM, respectively). Neither enzyme was able to remove galactose residues from intact guar gum, but both were capable of removing galactose residues from guar gum which had been degraded into large fragments by mannanase. The increase in specific activity of alpha-galactosidase which was associated with growth on guar gum was due to an increase in the specific activity of enzyme I. Low, constitutive levels of enzyme II also were produced. By contrast, enzyme II was the only alpha-galactosidase that was detectable in bacteria which had been grown on galactose, melibiose, raffinose, or stachyose. Images PMID:2981815

  14. Effect of chitosan chewing gum on reducing serum phosphorus in hemodialysis patients: a multi-center, randomized, double-blind, placebo-controlled trial

    PubMed Central

    2014-01-01

    Background HS219 (40 mg chitosan-loaded chewing gum) is designed to bind salivary phosphorus as an add-on to available phosphorus binders. We performed a randomized, placebo-controlled, double-blind study to evaluate the efficacy and safety of HS219 in hemodialysis (HD) patients with hyperphosphatemia as an add-on to phosphorus binders. Methods Sixty-eight HD patients who were maintained on calcium carbonate (n?=?33) or sevelamer hydrochloride (n?=?35) were enrolled. The primary end point was a change in serum phosphorus levels. Secondary end points included changes in levels of salivary phosphorus, serum calcium, parathyroid hormone (PTH), and intact fibroblast growth factor (iFGF) 23. Results Sixty-three patients chewed either HS219 (n?=?35) or placebo (n?=?28) for 30 min, three times a day, for 3 weeks. HS219 was well tolerated and safe. However, HS219 was not superior to placebo with additional reduction of serum phosphorus with respect to phosphorus binders at the end of the chewing period. There were no significant effects of HS219 on reduction of salivary phosphorus, serum calcium, iPTH, or iFGF23 levels. Conclusions The chitosan-loaded chewing gum HS219 does not affect serum and salivary phosphorus levels in Japanese HD patients with hyperphosphatemia. Our findings do not support previous findings that 20 mg of chitosan-loaded chewing gum reduces serum and salivary phosphorus levels. Trail registration ClinicalTrials.gov NCT01039428, 24 December, 2009. PMID:24968790

  15. Guar gum solutions for improved delivery of iron particles in porous media (Part 2): Iron transport tests and modeling in radial geometry

    NASA Astrophysics Data System (ADS)

    Tosco, Tiziana; Gastone, Francesca; Sethi, Rajandrea

    2014-10-01

    In the present work column transport tests were performed in order to study the mobility of guar-gum suspensions of microscale zero-valent iron particles (MZVI) in porous media. The results were analyzed with the purpose of implementing a radial model for the design of full scale interventions. The transport tests were performed using several concentrations of shear thinning guar gum solutions as stabilizer (1.5, 3 and 4 g/l) and applying different flow rates (Darcy velocity in the range 1 · 10- 4 to 2 · 10- 3 m/s), representative of different distances from the injection point in the radial domain. Empirical relationships, expressing the dependence of the deposition and release parameters on the flow velocity, were derived by inverse fitting of the column transport tests using a modified version of E-MNM1D (Tosco and Sethi, 2010) and the user interface MNMs (www.polito.it/groundwater/software). They were used to develop a comprehensive transport model of MZVI suspensions in radial coordinates, called E-MNM1R, which takes into account the non Newtonian (shear thinning) rheological properties of the dispersant fluid and the porous medium clogging associated with filtration and sedimentation in the porous medium of both MZVI and guar gum residual undissolved particles. The radial model was run in forward mode to simulate the injection of MZVI dispersed in guar gum in conditions similar to those applied in the column transport tests. In a second stage, we demonstrated how the model can be used as a valid tool for the design and the optimization of a full scale intervention. The simulation results indicated that several concurrent aspects are to be taken into account for the design of a successful delivery of MZVI/guar gum slurries via permeation injection, and a compromise is necessary between maximizing the radius of influence of the injection and minimizing the injection pressure, to guarantee a sufficiently homogeneous distribution of the particles around the injection point and to prevent preferential flow paths.

  16. Guar gum solutions for improved delivery of iron particles in porous media (part 2): iron transport tests and modeling in radial geometry.

    PubMed

    Tosco, Tiziana; Gastone, Francesca; Sethi, Rajandrea

    2014-10-01

    In the present work column transport tests were performed in order to study the mobility of guar-gum suspensions of microscale zero-valent iron particles (MZVI) in porous media. The results were analyzed with the purpose of implementing a radial model for the design of full scale interventions. The transport tests were performed using several concentrations of shear thinning guar gum solutions as stabilizer (1.5, 3 and 4g/l) and applying different flow rates (Darcy velocity in the range 1·10(-4) to 2·10(-3)m/s), representative of different distances from the injection point in the radial domain. Empirical relationships, expressing the dependence of the deposition and release parameters on the flow velocity, were derived by inverse fitting of the column transport tests using a modified version of E-MNM1D (Tosco and Sethi, 2010) and the user interface MNMs (www.polito.it/groundwater/software). They were used to develop a comprehensive transport model of MZVI suspensions in radial coordinates, called E-MNM1R, which takes into account the non Newtonian (shear thinning) rheological properties of the dispersant fluid and the porous medium clogging associated with filtration and sedimentation in the porous medium of both MZVI and guar gum residual undissolved particles. The radial model was run in forward mode to simulate the injection of MZVI dispersed in guar gum in conditions similar to those applied in the column transport tests. In a second stage, we demonstrated how the model can be used as a valid tool for the design and the optimization of a full scale intervention. The simulation results indicated that several concurrent aspects are to be taken into account for the design of a successful delivery of MZVI/guar gum slurries via permeation injection, and a compromise is necessary between maximizing the radius of influence of the injection and minimizing the injection pressure, to guarantee a sufficiently homogeneous distribution of the particles around the injection point and to prevent preferential flow paths. PMID:25063698

  17. Magnetism and Magnetic Properties

    NSDL National Science Digital Library

    Roberta Schneck

    2011-10-13

    Students will identify properties of magnetism and begin to develop understanding of their practical applications. Students will also begin to develop understanding of the essential nature of Earth's magnetic fields.

  18. Development, validation and influence factor analysis of a near-infrared method for the molecular weight determination of xanthan gum.

    PubMed

    Song, Zhigang; Ling, Peixue; Zang, Hengchang; Li, Lian; Wang, Jinfeng; Jin, Yan; Shao, Huarong; Zhu, Xiqiang; Liu, Fei; Wang, Fengshan

    2015-01-22

    A practical molecular weight determination model of xanthan gum (XG), based on near-infrared (NIR) spectroscopy, was built in this study. Two sample measurement modules, integrating sphere module and fiber-optic probe module, were compared, and the best partial least square (PLS) regression model was based on fiber-optic probe module. The values of coefficient of determination in calibration (R(2)c), coefficient of determination in prediction (R(2)p), residual predictive deviation (RPD) and root mean square error of prediction (RMSEP) were 0.967, 0.975, 6.028 and 0.250×10(6)Da, respectively. The molecular weight range, linearity, accuracy and precision of the established method were also validated. Furthermore, influence factors on this method were discussed in order to establish an appropriate measurement protocol. Results showed that the proposed NIR method may be suitable for practical applications in manufacturing plants and probably be accepted as a good alternative approach for fast determination of molecular weight of XG in production process. PMID:25439935

  19. Alginate gel-coated oil-entrapped alginate-tamarind gum-magnesium stearate buoyant beads of risperidone.

    PubMed

    Bera, Hriday; Boddupalli, Shashank; Nandikonda, Sridhar; Kumar, Sanoj; Nayak, Amit Kumar

    2015-07-01

    A novel alginate gel-coated oil-entrapped calcium-alginate-tamarind gum (TG)-magnesium stearate (MS) composite floating beads was developed for intragastric risperidone delivery with a view to improving its oral bioavailability. The TG-blended alginate core beads containing olive oil and MS as low-density materials were accomplished by ionotropic gelation technique. Effects of polymer-blend ratio (sodium alginate:TG) and crosslinker (CaCl2) concentration on drug entrapment efficiency (DEE, %) and cumulative drug release after 8h (Q8h, %) were studied to optimize the core beads by a 3(2) factorial design. The optimized beads (F-O) exhibited DEE of 75.19±0.75% and Q8h of 78.04±0.38% with minimum errors in prediction. The alginate gel-coated optimized beads displayed superior buoyancy and sustained drug release property. The drug release profiles of the drug-loaded uncoated and coated beads were best fitted in Higuchi kinetic model with Fickian and anomalous diffusion driven mechanisms, respectively. The optimized beads yielded a notable sustained drug release profile as compared to marketed immediate release preparation. The uncoated and coated Ca-alginate-TG-MS beads were also characterized by SEM, FTIR and P-XRD analyses. Thus, the newly developed alginate-gel coated oil-entrapped alginate-TG-MS composite beads are suitable for intragastric delivery of risperidone over a prolonged period of time. PMID:25861741

  20. Microencapsulation of purified amylase enzyme from pitaya (Hylocereus polyrhizus) peel in Arabic gum-chitosan using freeze drying.

    PubMed

    Amid, Mehrnoush; Manap, Yazid; Zohdi, Nor Khanani

    2014-01-01

    Amylase is one of the most important enzymes in the world due to its wide application in various industries and biotechnological processes. In this study, amylase enzyme from Hylocereus polyrhizus was encapsulated for the first time in an Arabic gum-chitosan matrix using freeze drying. The encapsulated amylase retained complete biocatalytic activity and exhibited a shift in the optimum temperature and considerable increase in the pH and temperature stabilities compared to the free enzyme. Encapsulation of the enzyme protected the activity in the presence of ionic and non-ionic surfactants and oxidizing agents (H?O?) and enhanced the shelf life. The storage stability of amylase is found to markedly increase after immobilization and the freeze dried amylase exhibited maximum encapsulation efficiency value (96.2%) after the encapsulation process. Therefore, the present study demonstrated that the encapsulation of the enzyme in a coating agent using freeze drying is an efficient method to keep the enzyme active and stable until required in industry. PMID:24662085

  1. Self-emulsification of alkaline-dissolved clove bud oil by whey protein, gum arabic, lecithin, and their combinations.

    PubMed

    Luo, Yangchao; Zhang, Yue; Pan, Kang; Critzer, Faith; Davidson, P Michael; Zhong, Qixin

    2014-05-14

    Low-cost emulsification technologies using food ingredients are critical to various applications. In the present study, a novel self-emulsification technique was studied to prepare clove bud oil (CBO) emulsions, without specialized equipment or organic solvents. CBO was first dissolved in hot alkaline solutions, added at 1% v/v into neutral solutions with 1% w/v emulsifier composed of whey protein concentrate (WPC), gum arabic, lecithin, or their equal mass mixtures, and adjusted to pH 7.0. The self-emulsification process did not affect UV-vis absorption spectrum, reversed-phase HPLC chromatogram, or antimicrobial activity of CBO against Escherichia coli O157:H7, Listeria monocytogenes Scott A, and Salmonella Enteritidis. The entrapment efficiency after extraction by petroleum ether was determined to be about 80%. Most emulsions were stable during 7 days of storage. Emulsions prepared with WPC had smaller particles, whereas emulsions prepared with emulsifier mixtures had more stable particle dimensions. The studied self-emulsification technique may find numerous applications in the preparation of low-cost food emulsions. PMID:24758517

  2. Does soil nitrogen influence growth, water transport and survival of snow gum (Eucalyptus pauciflora Sieber ex Sprengel.) under CO enrichment?

    PubMed

    Atwell, Brian J; Henery, Martin L; Ball, Marilyn C

    2009-05-01

    Eucalyptus pauciflora Sieber ex Sprengel. (snow gum) was grown under ambient (370 microL L(-1)) and elevated (700 microL L(-1)) atmospheric [CO2] in open-top chambers (OTCs) in the field and temperature-controlled glasshouses. Nitrogen applications to the soil ranged from 0.1 to 2.75 g N per plant. Trees in the field at high N levels grew rapidly during summer, particularly in CO2-enriched atmosphere, but suffered high mortality during summer heatwaves. Generally, wider and more numerous secondary xylem vessels at the root-shoot junction in CO2-enriched trees conferred fourfold higher below-ground hydraulic conductance. Enhanced hydraulic capacity was typical of plants at elevated [CO2] (in which root and shoot growth was accelerated), but did not result from high N supply. However, because high rates of N application consistently made trees prone to dehydration during heatwaves, glasshouse studies were required to identify the effect of N nutrition on root development and hydraulics. While the effects of elevated [CO2] were again predominantly on hydraulic conductivity, N nutrition acted specifically by constraining deep root penetration into soil. Specifically, 15-40% shallower root systems supported marginally larger shoot canopies. Independent changes to hydraulics and root penetration have implications for survival of fertilized trees under elevated atmospheric [CO2], particularly during water stress. PMID:19210643

  3. Effects of locust bean gum and mono- and diglyceride concentrations on particle size and melting rates of ice cream.

    PubMed

    Cropper, S L; Kocaoglu-Vurma, N A; Tharp, B W; Harper, W J

    2013-06-01

    The objective of this study was to determine how varying concentrations of the stabilizer, locust bean gum (LBG), and different levels of the emulsifier, mono- and diglycerides (MDGs), influenced fat aggregation and melting characteristics of ice cream. Ice creams were made containing MDGs and LBG singly and in combination at concentrations ranging between 0.0% to 0.14% and 0.0% to 0.23%, respectively. Particle size analysis, conducted on both the mixes and ice cream, and melting rate testing on the ice cream were used to determine fat aggregation. No significant differences (P < 0.05) were found between particle size values for experimental ice cream mixes. However, higher concentrations of both LBG and MDG in the ice creams resulted in values that were larger than the control. This study also found an increase in the particle size values when MDG levels were held constant and LBG amounts were increased in the ice cream. Ice creams with higher concentrations of MDG and LBG together had the greatest difference in the rate of melting than the control. The melting rate decreased with increasing LBG concentrations at constant MDG levels. These results illustrated that fat aggregation may not only be affected by emulsifiers, but that stabilizers may play a role in contributing to the destabilization of fat globules. PMID:23772704

  4. Flocculation and adsorption properties of biodegradable gum-ghatti-grafted poly(acrylamide-co-methacrylic acid) hydrogels.

    PubMed

    Mittal, H; Jindal, R; Kaith, B S; Maity, A; Ray, S S

    2015-01-22

    This study reports the microwave-assisted synthesis of gum-ghatti (Gg)-grafted poly(acrylamide-co-methacrylic acid) (AAm-co-MAA) hydrogels for the development of biodegradable flocculants and adsorbents. The synthesized hydrogels were characterized using TGA, FTIR and SEM. TGA studies revealed that the synthesized hydrogels were thermally more stable than pristine Gg and exhibited maximum swelling capacity of 1959% at 60°C in neutral pH. The optimal Gg-cl-P(AAm-co-MAA) hydrogel was successfully employed for the removal of saline water from various petroleum fraction-saline emulsions. The maximum flocculation efficiency was achieved in an acidic clay suspension with a 15 mg polymer dose at 40°C. Moreover, the synthesized hydrogel adsorbed 94% and 75% of Pb(2+) and Cu(2+), respectively, from aqueous solutions. Finally, the Gg-cl-P(AAm-co-MAA) hydrogel could be degraded completely within 50 days. In summary, the Gg-cl-P(AAm-co-MAA) hydrogel was demonstrated to have potential for use as flocculants and heavy metal absorbents for industrial waste water treatment. PMID:25439940

  5. Mechanism insights into enhanced trichloroethylene removal using xanthan gum-modified microscale zero-valent iron particles.

    PubMed

    Xin, Jia; Han, Jun; Zheng, Xilai; Shao, Haibing; Kolditz, Olaf

    2015-03-01

    This report focuses on the enhancement in trichloroethylene (TCE) removal from contaminated groundwater using xanthan gum (XG)-modified, microscale, zero-valent iron (mZVI). Compared with bare mZVI, XG-coated mZVI increased the TCE removal efficiency by 30.37% over a 480-h experimental period. Because the TCE removal is attributed to both sorption and reduction processes, the contributions from sorption and reduction were separately investigated to determine the mechanism of XG on TCE removal using mZVI. The results showed that the TCE sorption capacity of mZVI was lower in the presence of XG, whereas the TCE reduction capacity was significantly increased. The FTIR spectra confirmed that XG, which is rich in hydrophilic functional groups, was adsorbed onto the iron surface through intermolecular hydrogen bonds, which competitively repelled the sorption and mass transfer of TCE toward reactive sites. The variations in the pH, Eh, and Fe(2+) concentration as functions of the reaction time were recorded and indicated that XG buffered the solution pH, inhibited surface passivation, and promoted TCE reduction by mZVI. Overall, the XG-modified mZVI was considered to be potentially effective for the in-situ remediation of TCE contaminated groundwater due to its high stability and dechlorination reactivity. PMID:25556871

  6. Chitosan coated alginate-xanthan gum bead enhanced pH and thermotolerance of Lactobacillus plantarum LAB12.

    PubMed

    Fareez, Ismail M; Lim, Siong Meng; Mishra, Rakesh K; Ramasamy, Kalavathy

    2015-01-01

    The vulnerability of probiotics at low pH and high temperature has limited their optimal use as nutraceuticals. This study addressed these issues by adopting a physicochemical driven approach of incorporating Lactobacillus plantarum LAB12 into chitosan (Ch) coated alginate-xanthan gum (Alg-XG) beads. Characterisation of Alg-XG-Ch, which elicited little effect on bead size and polydispersity, demonstrated good miscibility with improved bead surface smoothness and L. plantarum LAB12 entrapment when compared to Alg, Alg-Ch and Alg-XG. Sequential incubation of Alg-XG-Ch in simulated gastric juice and intestinal fluid yielded high survival rate of L. plantarum LAB12 (95%) at pH 1.8 which in turn facilitated sufficient release of probiotics (>7 log CFU/g) at pH 6.8 in both time- and pH-dependent manner. Whilst minimising viability loss at 75 and 90 °C, Alg-XG-Ch improved storage durability of L. plantarum LAB12 at 4 °C. The present results implied the possible use of L. plantarum LAB12 incorporated in Alg-XG-Ch as new functional food ingredient with health claims. PMID:25450046

  7. Chromosome Map of Xanthomonas campestris pv. campestris 17 with Locations of Genes Involved in Xanthan Gum Synthesis and Yellow Pigmentation

    PubMed Central

    Tseng, Yi-Hsiung; Choy, Ka-Tim; Hung, Chih-Hsin; Lin, Nien-Tsung; Liu, Jane-Yu; Lou, Chih-Hong; Yang, Bih-Ying; Wen, Fu-Shyan; Weng, Shu-Fen; Wu, Jung-Rung

    1999-01-01

    No plasmid was detected in Xanthomonas campestris pv. campestris 17, a strain of the causative agent of black rot in cruciferous plants isolated in Taiwan. Its chromosome was cut by PacI, PmeI, and SwaI into five, two, and six fragments, respectively, and a size of 4.8 Mb was estimated by summing the fragment lengths in these digests. Based on the data obtained from partial digestion and Southern hybridization using probes common to pairs of the overlapping fragments or prepared from linking fragments, a circular physical map bearing the PacI, PmeI, and SwaI sites was constructed for the X. campestris pv. campestris 17 chromosome. Locations of eight eps loci involved in exopolysaccharide (xanthan gum) synthesis, two rrn operons each possessing an unique I-CeuI site, one pig cluster required for yellow pigmentation, and nine auxotrophic markers were determined, using mutants isolated by mutagenesis with Tn5(pfm)CmKm. This transposon contains a polylinker with sites for several rare-cutting restriction endonucleases located between the chloramphenicol resistance and kanamycin resistance (Kmr) genes, which upon insertion introduced additional sites into the chromosome. The recA and tdh genes, with known sequences, were mapped by tagging with the polylinker-Kmr segment from Tn5(pfm)CmKm. This is the first map for X. campestris and would be useful for genetic studies of this and related Xanthomonas species. PMID:9864320

  8. Preparation of poly(acrylamide-co-acrylic acid)-grafted gum and its flocculation and biodegradation studies.

    PubMed

    Mittal, H; Mishra, Shivani B; Mishra, A K; Kaith, B S; Jindal, R; Kalia, S

    2013-10-15

    Biodegradation studies of Gum ghatti (Gg) and acrylamide-co-acrylic acid based flocculants [Gg-cl-poly(AAm-co-AA)] have been reported using the soil composting method. Gg-cl-poly(AAm-co-AA) was found to degrade 89.76% within 60 days. The progress of biodegradation at each stage was monitored through FT-IR and SEM. Polymer was synthesized under pressure using potassium persulphate-ascorbic acid as a redox initiator and N,N'-methylene-bis-acrylamide as a crosslinker. Synthesized polymer was found to show pH, temperature and ionic strength of the cations dependent swelling behavior. Gg-cl-poly(AAm-co-AA) was utilized for the selective absorption of saline from different petroleum fraction-saline emulsions. The flocculation efficiency of the polymer was studied as a function of polymer dose, temperature and pH of the solution. Gg-cl-poly(AAm-co-AA) showed maximum flocculation efficiency with 20 mol L(-1) polymer dose in acidic medium at 50 °C. PMID:23987360

  9. Application of maltodextrin and gum Arabic in microencapsulation of saffron petal's anthocyanins and evaluating their storage stability and color.

    PubMed

    Mahdavee Khazaei, K; Jafari, S M; Ghorbani, M; Hemmati Kakhki, A

    2014-05-25

    In this work, anthocyanin stability and color of encapsulated freeze-dried saffron petal's extract with various matrices consisting gum Arabic (AG) and maltodextrin (M7 and M20) were studied. Total anthocyanins of powders and color parameters (a*, b*, L*, C, H° and TCD) were measured immediately after production and during storage up to 10 weeks by pH differential method and computer vision, respectively. Different compounds of wall materials did not show any significant differences in terms of stabilizing anthocyanins (P<0.01) and no significant decrease in anthocyanin content of the powders was observed after storage. The efficiency order of wall materials considering total color differences (TCD) was AG>M20>M7. By evaluating 3D surface and Cox trace plots it was revealed that wall formulas which had the lowest amount of AG and highest amounts of M20 and M7 showed the lowest total color differences after storage (P<0.05). To conclude, microencapsulation by freeze drying could be recommended as a suitable method for stabilizing anthocyanins of saffron petal's extract. PMID:24708952

  10. Comparisons of ethanol extracts of chinese propolis (poplar type) and poplar gums based on the antioxidant activities and molecular mechanism.

    PubMed

    Zhang, Jianglin; Cao, Xueping; Ping, Shun; Wang, Kai; Shi, Jinhu; Zhang, Cuiping; Zheng, Huoqing; Hu, Fuliang

    2015-01-01

    The biological activities of propolis are varied from plant sources and the prominent antioxidant effects of Chinese propolis (poplar type) have been extensively reported. Oxidative stress is associated with inflammation and induces many diseases. In the study, to evaluate antioxidant capacities and clarify the underlying molecular mechanisms of ethanol extracts of Chinese propolis (EECP) and ethanol extracts of poplar gums (EEPG), we analyzed their compositions by HPLC, evaluating their free radical scavenging activities and reducing power by chemical analysis methods. Moreover, we studied the roles of EECP and EEPG on the elimination of ROS and expressions of antioxidant genes (HO-1, TrxR1, GCLM, and GCLC) in RAW264.7 cells. We further investigated the effects of MAPKs on the antioxidant genes expression by specific inhibitors. The nucleus translocation effects of Nrf2 were also measured by confocal microscopy analysis. The results indicated that EECP had higher TPC and FDC values but regarding TFC values were not significant. EECP also possessed more contents of 11 compounds than EEPG. Both phytochemical analysis and cell experiment reflected that EECP exerted stronger antioxidant activities than EEPG. EECP and EEPG enhanced endogenous antioxidant defenses by eliminating reactive oxygen species directly and activating Erk-Nrf2-HO1, GCLM, and TrxR1 signal pathways. PMID:25802536

  11. Gastroprotective Properties of Cashew Gum, a Complex Heteropolysaccharide of Anacardium occidentale, in Naproxen-Induced Gastrointestinal Damage in Rats.

    PubMed

    Carvalho, Nathalia S; Silva, Mônica M; Silva, Renan O; Nicolau, Lucas A D; Sousa, Francisca Beatriz M; Damasceno, Samara R B; Silva, Durcilene A; Barbosa, André L R; Leite, José Roberto S A; Medeiros, Jand Venes R

    2015-05-01

    Preclinical Research Long-term use nonsteroidal anti-inflammatory drug is associated with gastrointestinal (GI) lesion formation. The aim of this study was to investigate the protective activity of cashew gum (CG), a complex heteropolysaccharide extracted from Anacardium occidentale on naproxen (NAP)-induced GI damage. Male Wistar rats were pretreated with vehicle or CG (1, 3, 10, and 30 mg/kg, p.o.) twice daily for 2 days; after 1 h, NAP (80 mg/kg, p.o.) was administered. The rats were euthanized on the 2nd day of treatment, 4 h after NAP administration. Stomach lesions were measured using digital calipers. The medial small intestine was used for the evaluation of macroscopic lesion scores. Samples of the stomach and the intestine were used for histological evaluation, and assays for glutathione (GSH), malonyldialdehyde (MDA), and myeloperoxidase (MPO). Additional rats were used to measure gastric mucus and secretion. Pretreatment with CG reduced the macroscopic and microscopic damage induced by NAP. CG significantly attenuated NAP-induced alterations in MPO, GSH, and MDA levels. Furthermore, CG returned adherent mucus levels to normal values. These results suggest that CG has a protective effect against GI damage via mechanisms that involve the inhibition of inflammation and increasing the amount of adherent mucus in mucosa. Drug Dev Res 73 : 143-151, 2015. © 2015 Wiley Periodicals, Inc. PMID:25959135

  12. Earthquakes Promote Bacterial Genetic Exchange in Serpentinite Crevices

    NASA Astrophysics Data System (ADS)

    Naoto, Yoshida; Fujiura, Nori

    2009-04-01

    We report the results of our efforts to study the effects of seismic shaking on simulated biofilms within serpentinite fissures. A colloidal solution consisting of recipient bacterial cells (Pseudomonas sp. or Bacillus subtilis), donor plasmid DNA encoded for antibiotic resistance, and chrysotile (an acicular clay mineral that forms in crevices of serpentinite layers) were placed onto an elastic body made from gellan gum, which acted as the biofilm matrix. Silica beads, as rock analogues (i.e., chemically inert mechanical serpentinite), were placed on the gellan surface, which was coated with the colloidal solution. A rolling vibration similar to vibrations generated by earthquakes was applied, and the silica beads moved randomly across the surface of the gellan. This resulted in the recipient cells' acquiring plasmid DNA and thus becoming genetically transformed to demonstrate marked antibiotic resistance. Neither Pseudomonas sp. nor B. subtilis were transformed by plasmid DNA when chrysotile was substituted for by kaolinite or bentonite in the colloidal solution. Tough gellan (1.0%) promoted the introduction of plasmid DNA into Pseudomonas sp., but soft gellan (0.3%) had no such effect. Genetic transformation of bacteria on the surface of gellan by exposure to exogenous plasmid DNA required seismic shaking and exposure to the acicular clay mineral chrysotile. These experimental results suggest that bacterial genetic exchange readily occurs when biofilms that form in crevices of serpentinite are exposed to seismic shaking. Seismic activity may be a key factor in bacterial evolution along with the formation of biofilms within crevices of serpentinite.

  13. Chios mastic gum extract and isolated phytosterol tirucallol exhibit anti-inflammatory activity in human aortic endothelial cells.

    PubMed

    Loizou, Stella; Paraschos, Sotirios; Mitakou, Sofia; Chrousos, George P; Lekakis, Ioannis; Moutsatsou, Paraskevi

    2009-05-01

    Chios mastic gum (CMG) is a white, semitransparent, natural resin that is obtained as a trunk exudate from mastic trees. Triterpenic compounds and phytosterols like tirucallol are among its major components. CMG has been associated with cardiovascular protection, exerting its effect mainly through increasing the antioxidant defense system, and effectively lowering the levels of serum cholesterol in human subjects. However, data on its anti-inflammatory effect on endothelium are scarce. Attachment of leukocytes to the vascular endothelium and the subsequent migration of cells into the vessel wall are early events in atherogenesis, and this process requires the expression of endothelial adhesion molecules. In this study, we examined the effect of CMG neutral extract (25-200 microg/ml) and tirucallol (0.1-100 microM) on the following: 1) the expression of adhesion molecules (VCAM-1 and ICAM-1) by Cell ELISA and 2) the attachment of monocytes (U937 cells) in TNF-alpha stimulated Human Aortic Endothelial Cells (HAEC) by Adhesion assay. The impact of treatment with CMG neutral extract and tirucallol in NFkB phosphorylation was also examined by a cell-based ELISA kit. Both CMG extract and tirucallol inhibit significantly VCAM-1 and ICAM-1 expression in TNF-alpha-stimulated HAEC. They also inhibit significantly the binding of U937 cells to TNF-alpha-stimulated HAEC and attenuate the phosphorylation of NFkB p65. This study extends existing data regarding the cardioprotective effect of CMG, expands the spectrum of known phytosterols with potent antiatheromatic activity, provides new insight into the mechanisms underlying the beneficial effect of CMG on endothelial function, and may aid in design of new therapy for intervention in atherosclerosis. PMID:19234052

  14. Lytic enzyme production optimization using low-cost substrates and its application in the clarification of xanthan gum culture broth.

    PubMed

    da Silva, Cíntia Reis; Silva, Marilia Lordelo Cardoso; Kamida, Helio Mitoshi; Goes-Neto, Aristoteles; Koblitz, Maria Gabriela Bello

    2014-07-01

    Lytic enzymes are widely used in industrial biotechnology as they are able to hydrolyze the bacterial cell wall. One application of these enzymes is the clarification of the culture broth for the production of xanthan gum, because of its viability in viscous media and high specificity. The screening process for filamentous fungi producing lytic enzymes, the optimization of production of these enzymes by the selected microorganism, and the optimization of the application of the enzymes produced in the clarification of culture broth are presented in this article. Eleven fungal isolates were tested for their ability to produce enzymes able to increase the transmittance of the culture broth containing cells of Xanthomonas campestris. To optimize the secretion of lytic enzymes by the selected microorganism the following variables were tested: solid substrate, initial pH, incubation temperature, and addition of inducer (gelatin). Thereafter, secretion of the enzymes over time of incubation was assessed. To optimize the clarification process a central composite rotational design was applied in which the pH of the reaction medium, the dilution of the broth, and the reaction temperature were evaluated. The isolate identified as Aspergillus tamarii was selected for increasing the transmittance of the broth from 2.1% to 54.8%. The best conditions for cultivation of this microorganism were: use of coconut husk as solid substrate, with 90% moisture, at 30°C for 20 days. The lytic enzymes produced thereby were able to increase the transmittance of the culture broth from 2.1% to 70.6% at 65°C, without dilution and without pH adjustment. PMID:25473487

  15. Gum arabic capped-silver nanoparticles inhibit biofilm formation by multi-drug resistant strains of Pseudomonas aeruginosa.

    PubMed

    Ansari, Mohammad Azam; Khan, Haris Manzoor; Khan, Aijaz Ahmed; Cameotra, Swaranjit Singh; Saquib, Quaiser; Musarrat, Javed

    2014-07-01

    Clinical isolates (n?=?55) of Pseudomonas aeruginosa were screened for the extended spectrum ?-lactamases and metallo-?-lactamases activities and biofilm forming capability. The aim of the study was to demonstrate the antibiofilm efficacy of gum arabic capped-silver nanoparticles (GA-AgNPs) against the multi-drug resistant (MDR) biofilm forming P. aeruginosa. The GA-AgNPs were characterized by UV-spectroscopy, X-ray diffraction, and high resolution-transmission electron microscopy analysis. The isolates were screened for their biofilm forming ability, using the Congo red agar, tube method and tissue culture plate assays. The biofilm forming ability was further validated and its inhibition by GA-AgNPs was demonstrated by performing the scanning electron microscopy (SEM) and confocal laser scanning microscopy. SEM analysis of GA-AgNPs treated bacteria revealed severely deformed and damaged cells. Double fluorescent staining with propidium iodide and concanavalin A-fluorescein isothiocyanate concurrently detected the bacterial cells and exopolysaccharides (EPS) matrix. The CLSM results exhibited the GA-AgNPs concentration dependent inhibition of bacterial growth and EPS matrix of the biofilm colonizers on the surface of plastic catheters. Treatment of catheters with GA-AgNPs at 50?µg?ml(-1) has resulted in 95% inhibition of bacterial colonization. This study elucidated the significance of GA-AgNPs, as the next generation antimicrobials, in protection against the biofilm mediated infections caused by MDR P. aeruginosa. It is suggested that application of GA-AgNPs, as a surface coating material for dispensing antibacterial attributes to surgical implants and implements, could be a viable approach for controlling MDR pathogens after adequate validations in clinical settings. PMID:24403133

  16. Antibacterial effects of gum kondagogu reduced/stabilized silver nanoparticles in combination with various antibiotics: a mechanistic approach

    NASA Astrophysics Data System (ADS)

    Rastogi, Lori; Kora, Aruna Jyothi; Sashidhar, R. B.

    2015-06-01

    Gum kondagogu reduced/stabilized silver nanoparticles (GK-AgNPs) were evaluated for their increased antibacterial and antibiofilm activities in combination with various antibiotics (ciprofloxacin, streptomycin and gentamicin) against Gram-positive ( Staphylococcus aureus 25923, Staphylococcus aureus 49834) and Gram-negative ( Escherichia coli 25922, Pseudomonas aeruginosa 27853) bacteria. The micro-broth dilution assay suggested an enhanced antibacterial activity of GK-AgNPs in combination with ciprofloxacin and aminoglycosides (streptomycin and gentamicin) against tested strains. Though the antibacterial activity of GK-AgNPs was found to increase significantly in the presence of antibiotics, the % enhancement was found to depend on both types of antibiotic and bacterial strain. It was also found that GK-AgNPs (1 µg/mL) in combination with various antibiotics at sub-MIC concentrations could inhibit 70 % of the bacterial biofilm formation as compared to respective controls. The enhanced antibacterial activity was due to the increased production of intracellular reactive oxygen species in bacteria when treated with a combination of GK-AgNPs and streptomycin as compared to individual treatment. The increased oxidative stress led to increased membrane damage as assessed by live/dead assay and higher levels of potassium ion release from the cells treated with both silver nanoparticles and streptomycin. The results suggested that the combination of antibiotics with GK-AgNPs has an enhanced antibacterial action. Further, the GK-AgNPs were found to be biocompatible up to a concentration of 2.5 µg/mL as assessed with MTT assay on HeLa cell line. The results suggest that GK-AgNPs could potentially be used as in vivo antibacterial agent in combination with antibiotics to overcome the problem of antibiotic resistance.

  17. Gum kondagogu reduced/stabilized silver nanoparticles as direct colorimetric sensor for the sensitive detection of Hg²? in aqueous system.

    PubMed

    Rastogi, Lori; Sashidhar, R B; Karunasagar, D; Arunachalam, J

    2014-01-01

    A highly sensitive and selective method is reported for the colorimetric detection of Hg(2+) in aqueous system by using label free silver nanoparticles (Ag NPs). Ag NPs used in this method were synthesized by gum kondagogu (GK) which acted as both reducing and stabilizing agent. The average size of the GK-Ag NPs was found to be 5.0 ± 2.8 nm as revealed by transmission electron microscope (TEM) analysis and the nanoparticles were stable at various pH conditions (pH 4-11) and salt concentrations (5-100 mM). The GK reduced/stabilized Ag NPs (GK-Ag NPs) were directly used for the selective colorimetric reaction with Hg(2+) without any further modification. The bright yellow colour of Ag NPs was found to fade in a concentration dependent manner with the added Hg(+) ions. The fading response was directly correlated with increasing concentration of Hg(2+). More importantly, this response was found to be highly selective for Hg(2+) as the absorption spectra were found to be unaffected by the presence of other ions like; Na(+), K(+), Mg(2+), Ca(2+), Cu(2+), Ni(2+), Co(2+), As(3+), Fe(2+), Cd(2+), etc. The metal sensing mechanism is explained based on the turbidometric and X-ray diffraction (XRD) analysis of GK-Ag NPs with Hg(2+). The proposed method was successfully applied for the determination of Hg(2+) in various ground water samples. The reported method can be effectively used for the quantification of total Hg(2+) in samples, wherein the organic mercury is first oxidized to inorganic form by ultraviolet (UV) irradiation. The limit of quantification for Hg(2+) using the proposed method was as low as 4.9 × 10(-8) mol L(-1) (50 nM). The proposed method has potential application for on-field qualitative detection of Hg(2+) in aqueous environmental samples. PMID:24274277

  18. Study of the behavior of the diffraction efficiency of a function of thickness using holographic gratings as material registration with gum Arabic ammonium dichromate

    NASA Astrophysics Data System (ADS)

    Pinto-Iguanero, B.; Olivares-Pérez, A.; Toxqui-López, S.; Fuentes-Tapia, I.

    2012-03-01

    This work presents a study of gum Arabic as holographic recording material, and to quantify the parameter of the diffraction efficiency through holographic diffraction gratings. This material exhibits excellent properties such as transparency, consistency, easy to handle, non toxic, non degradable. It also shows a low moisture absorption environment, hydro-phobic behavior. It is easy to produce a homogeneous thin film layer with a smooth texture on a glass substrate with gravity techniques. It also has adhesive properties. Also shown is a study of the pH behavior of this matrix, related to its viscosity.

  19. Assessment of hupu gum for its carrier property in the design and evaluation of solid mixtures of poorly water soluble drug - rofecoxib.

    PubMed

    Vadlamudi, Harini Chowdary; Raju, Y Prasanna; Asuntha, G; Nair, Rahul; Murthy, K V Ramana; Vulava, Jayasri

    2014-01-01

    There are no reports about the pharmaceutical applications of hupu gum (HG). Hence the present study was undertaken to test its suitability in the dissolution enhancement of poorly water soluble drug. Rofecoxib (RFB) was taken as model drug. For comparison solid mixtures were prepared with carriers such as poly vinyl pyrrolidone (PVP), sodium starch glycollate (SSG) and guar gum (GG). Physical mixing (PM), co-grinding (CG), kneading (KT) and solvent evaporation (SE) techniques were used to prepare the solid mixtures, using all the carriers in different carrier and drug ratios. The solid mixtures were characterized by powder X-ray diffraction (XRD) and Fourier-transformed infrared spectroscopy (FTIR). There was a significant improvement in the dissolution rate of solid mixtures of HG, when compared with the solid mixtures of other carriers. There was an increase in dissolution rate with increase in concentration of HG upto 1:1 ratio of carrier and drug. No drug-carrier interaction was found by FTIR studies. XRD studies indicated reduction in crystallinity of the drug with increase in HG concentration. Hence HG could be a useful carrier for the dissolution enhancement of poorly water soluble drugs. PMID:24783235

  20. Efficient and rapid adsorption characteristics of templating modified guar gum and silica nanocomposite toward removal of toxic reactive blue and Congo red dyes.

    PubMed

    Pal, Sagar; Patra, Abhay Shankar; Ghorai, Soumitra; Sarkar, Amit Kumar; Mahato, Vivekananda; Sarkar, Supriyo; Singh, R P

    2015-09-01

    The present study highlights the potentiality of sol-gel synthesized guar gum-graft-poly (acrylamide)/silica (g-GG/SiO2) hybrid nanocomposite toward the rapid removal of toxic reactive blue 4 (RB) and Congo red (CR) dyes from aqueous solution. Various physicochemical characterizations support the feasibility of the functionalized guar gum matrix as efficient template for the formation of homogeneous nanoscale silica particles. The composite demonstrates rapid and superior adsorption efficiency of RB (Qmax: 579.01mgg(-1) within 40min) and CR (Qmax: 233.24mgg(-1) within 30min) dyes from aqueous environment. Here, the pH driven adsorption process depends strongly on the ionic strength of the salt solution. The adsorption kinetics data predicts that pseudo second-order (surface adsorption) and intraparticle diffusion take place simultaneously. The adsorption equilibrium is in good agreement with the Langmuir isotherm, while the thermodynamics study confirms spontaneous nature of the adsorption process. Desorption study predicts the excellent regenerative efficacy of nanocomposite. PMID:26002148