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1

Production of gellan gum by Sphingomonas paucimobilis NK2000 with soybean pomace  

Microsoft Academic Search

The ammonium nitrate as a nitrogen source for the production of gellan gum by Sphingomonas paucimobilis NK2000 enhanced the cell growth but its depletion was essential for higher production of gellan gum. The highest production of gellan gum was 3.27gl?1 when the concentrations of glucose and bacto-peptone were 2.0% (w\\/v) and 0.05% (w\\/v). The production of gellan gum by S.

Hyuck Jin; Nam-Kyu Lee; Myung-Kyo Shin; Sung-Koo Kim; David L Kaplan; Jin-Woo Lee

2003-01-01

2

Deproteinization of gellan gum produced by Sphingomonas paucimobilis ATCC 31461  

Microsoft Academic Search

Deproteinization is a technical bottleneck in the purification of viscous water-soluble polysaccharides. The aim of this work is to provide an appropriate approach to deproteinize crude gellan gum. Several methods of deproteinization were investigated, including Sevag method, alkaline protease, papain and neutral protease. The results revealed that Sevag method had high deproteinization efficiency (87.9%), but it showed dissatisfactory recovery efficiency

Xia Wang; Yong Yuan; Kainai Wang; Dezhong Zhang; Zhengting Yang; Ping Xu

2007-01-01

3

Gellan gum: a new biomaterial for cartilage tissue engineering applications.  

PubMed

Gellan gum is a polysaccharide manufactured by microbial fermentation of the Sphingomonas paucimobilis microorganism, being commonly used in the food and pharmaceutical industry. It can be dissolved in water, and when heated and mixed with mono or divalent cations, forms a gel upon lowering the temperature under mild conditions. In this work, gellan gum hydrogels were analyzed as cells supports in the context of cartilage regeneration. Gellan gum hydrogel discs were characterized in terms of mechanical and structural properties. Transmissionelectron microscopy revealed a quite homogeneous chain arrangement within the hydrogels matrix, and dynamic mechanical analysis allowed to characterize the hydrogels discs viscoelastic properties upon compression solicitation, being the compressive storage and loss modulus of approximately 40 kPa and 3 kPa, respectively, at a frequency of 1 Hz. Rheological measurements determined the sol-gel transition started to occur at approximately 36 degrees C, exhibiting a gelation time of approximately 11 s. Evaluation of the gellan gum hydrogels biological performance was performed using a standard MTS cytotoxicity test, which showed that the leachables released are not deleterious to the cells and hence were noncytotoxic. Gellan gum hydrogels were afterwards used to encapsulate human nasal chondrocytes (1 x 10(6) cells/mL) and culture them for total periods of 2 weeks. Cells viability was confirmed using confocal calcein AM staining. Histological observations revealed normal chondrocytes morphology and the obtained data supports the claim that this new biomaterial has the potential to serve as a cell support in the field of cartilage regeneration. PMID:19658177

Oliveira, J T; Martins, L; Picciochi, R; Malafaya, P B; Sousa, R A; Neves, N M; Mano, J F; Reis, R L

2010-06-01

4

Heavy metal biosorption by gellan gum gel beads  

Microsoft Academic Search

The Ni2+ accumulation in batch mode from diluted solutions by gel beads of gellan gum (GG), alginate, ?-carrageenan, agar, agarose, silica gel, polyacrylamide and two mixtures of GG+agar was investigated. All polymeric materials studied accumulated Ni2+, but gel beads of GG were stable, easily obtainable and showed the highest Ni2+ accumulation. The pH of the Ni2+ solution was not critical

Núria Lázaro; Asunción López Sevilla; Susana Morales; Ana M. Marqués

2003-01-01

5

An insight into the emerging exopolysaccharide gellan gum as a novel polymer.  

PubMed

The microbial exopolysaccharides are water-soluble polymers secreted by microorganisms during fermentation. The biopolymer gellan gum is a relatively recent addition to the family of microbial polysaccharides that is gaining much importance in food, pharmaceutical and chemical industries due to its novel properties. It is commercially produced by C.P. Kelco in Japan and the USA. This article presents a critical review of the available information on the gum synthesized by Sphingomonas paucimobilis with special emphasis on its fermentative production. Factors affecting the fermentative production of gellan gum and problems associated with mass transfer have been addressed. Classification and trade names of gellan gum has been specified. Characteristics of gellan gum with respect to its structure, physicochemical properties are discussed. An attempt has also been made to review the current and potential applications of gellan gum in food, pharmaceutical and other industries. PMID:23499110

Prajapati, Vipul D; Jani, Girish K; Zala, Bhumi S; Khutliwala, Tohra A

2013-04-01

6

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

Microsoft Academic Search

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

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

2006-01-01

7

Optimization of culture medium compositions for gellan gum production by a halobacterium Sphingomonas paucimobilis.  

PubMed

The effect of culture medium compositions on gellan gum production produced by fermentation with a halobacterium Sphingomonas paucimobilis QHZJUJW CGMCC2428 was studied. In this work, a fractional factorial design was applied to investigate the main factors that affected gellan gum production by S. paucimobilis QHZJUJW CGMCC2428. Sucrose was the best carbon source for gellan gum and peptone displayed better inducing effect. Central composite design and response surface methodology were adopted to derive a statistical model for optimizing submerged culture medium composition. These experimental results showed that the optimum culture medium for producing gellan gum was composed of 40.00 (w/v) sucrose, 3.00% peptone (w/v), MgSO4 (w/v), 9.20% KH2PO4 (w/v), 7.50% Na2HPO4 (w/v), 4.30% K2SO4 (w/v), pH 6.8-7.0. The maximal gellan gum was 19.89±0.68 g/L, which was agreed closely with the predicated value (20.12 g/L). After incubated for 72 h under the optimized culture medium in 5-L bioreactor, the gellan gum fermentation reached about 19.90±0.68 g/L, which was higher than that in the initial cultivation medium. PMID:25439950

Zhang, Jun; Dong, Ya-chen; Fan, Lin-lin; Jiao, Zhi-hua; Chen, Qi-he

2015-01-22

8

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

NASA Astrophysics Data System (ADS)

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.

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

2013-08-01

9

Enhanced gellan gum production by hydrogen peroxide (H2O 2) induced oxidative stresses in Sphingomonas paucimobilis.  

PubMed

In this study, the effect of H2O2-induced oxidative stress on gellan gum production and cell growth were investigated. Gellan gum production was improved and cell growth was inhibited by H2O2. A multiple H2O2 stresses with different concentrations were developed to optimize gellan gum production. A maximal gellan gum yield (22.52 g/L), which was 35.58 % higher than the control, was observed with 2, 2, 3, 4 mmol/L H2O2 added at 6, 12, 18, 24 h, respectively. Moreover, UDP-glucose pyrophosphorylase activity and glucosyltransferase activity were increased with H2O2 stresses. This new strategy of multiple H2O2-induced oxidative stresses would be further applied to gellan gum production in future study. PMID:23925529

Zhu, Guilan; Sheng, Long; Tong, Qunyi

2014-04-01

10

Antibacterial quaternized gellan gum based particles for controlled release of ciprofloxacin with potential dermal applications.  

PubMed

This paper presents the synthesis and characterization of gellan gum derivatives containing quaternary ammonium groups, with the purpose of obtaining particulate controlled release systems for ciprofloxacin. Quaternized gellan derivatives were synthesized by grafting N-(3-chloro-2-hydroxypropyl)-trimethyl ammonium chloride onto gellan primary hydroxyl groups by nucleophilic substitution, in the presence of alkali, under specific reaction conditions using various gellan/N-(3-chloro-2-hydroxypropyl)-trimethyl ammonium chloride molar ratios. Degree of quaternization was determined by (1)H NMR spectroscopy and AgNO3 conductometric titration. Thermal behavior was investigated for all materials by thermogravimetric analysis. A study of the degree of quaternization and effect of the reaction conditions upon activation energy of quaternized gellan derivatives for the main degradation step by applying the Kissinger method at four heating rates is also reported. The novelty that this work brings refers to obtaining quaternized gellan and chitosan based particles with retention of quaternary ammonium moieties' antibacterial activity. In vitro transdermal release tests of ciprofloxacin from loaded particles were carried out on rat skin in isotonic phosphate buffer solution (pH=7.43). Ciprofloxacin was released up to 24 h, confirming quaternized gellan-chitosan particles' potential as controlled release systems for topical dermal applications. PMID:24411380

Novac, O; Lisa, G; Profire, L; Tuchilus, C; Popa, M I

2014-02-01

11

The effect of deacetylated gellan gum on aesculin distribution in the posterior segment of the eye after topical administration.  

PubMed

The aim of the present work was to evaluate the effect of deacetylated gellan gum on delivering hydrophilic drug to the posterior segment of the eye. An aesculin-containing in situ gel based on deacetylated gellan gum (AG) was prepared and characterized. In vitro corneal permeation across isolated rabbit cornea of aesculin between AG and aesculin solution (AS) was compared. The results showed that deacetylated gellan gum promotes corneal penetration of aesculin. Pharmacokinetics and ocular tissue distribution of aesculin after topical administration in rabbit eye showed that AG greatly improved aesculin accumulation in posterior segmentsrelative to AS, which was probably attributed to conjunctivital/sclera pathway. The area-under-the-curve (AUC) for AG in aqueous humor, choroid-retina, sclera and iris-ciliary body were significantly larger than those of AS. AG can be used as a potential carrier for broading the application of aesculin. PMID:22643053

Chen, Qiuhong; Zheng, Yu; Li, Ye; Zeng, Ying; Kuang, Jianchao; Hou, Shixiang; Li, Xiaohui

2012-05-01

12

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

PubMed

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. Copyright © 2012 John Wiley & Sons, Ltd. PMID:23225767

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

2015-03-01

13

Rheological and mechanical properties of acellular and cell-laden methacrylated gellan gum hydrogels.  

PubMed

Tissue engineered hydrogels hold great potential as nucleus pulposus substitutes (NP), as they promote intervertebral disc (IVD) regeneration and re-establish its original function. But, the key to their success in future clinical applications greatly depends on its ability to replicate the native 3D micro-environment and circumvent their limitation in terms of mechanical performance. In the present study, we investigated the rheological/mechanical properties of both ionic- (iGG-MA) and photo-crosslinked methacrylated gellan gum (phGG-MA) hydrogels. Steady shear analysis, injectability and confined compression stress-relaxation tests were carried out. The injectability of the reactive solutions employed for the preparation of iGG-MA and phGG-MA hydrogels was first studied, then the zero-strain compressive modulus and permeability of the acellular hydrogels were evaluated. In addition, human intervertebral disc (hIVD) cells encapsulated in both iGG-MA and phGG-MA hydrogels were cultured in vitro, and its mechanical properties also investigated under dynamic mechanical analysis at 37°C and pH 7.4. After 21 days of culturing, hIVD cells were alive (Calcein AM) and the E' of ionic-crosslinked hydrogels and photo-crosslinked was higher than that observed for acellular hydrogels. Our study suggests that methacrylated gellan gum hydrogels present promising mechanical and biological performance as hIVD cells were producing extracellular matrix. PMID:23568694

Silva-Correia, Joana; Gloria, Antonio; Oliveira, Mariana B; Mano, João F; Oliveira, Joaquim M; Ambrosio, Luigi; Reis, Rui L

2013-12-01

14

Gellan gum microspheres containing a novel ?-amylase from marine Nocardiopsis sp. strain B2 for immobilization.  

PubMed

A Nocardiopsis sp. stain B2 with an ability to produce stable ?-amylase was isolated from marine sediments. The characterization of microorganism was done by biochemical tests and 16S rDNA sequencing. The ?-amylase was purified by gel filtration chromatography by using sephadex G-75. The molecular mass of the amylase was found to be 45 kDa by SDS-PAGE and gel filtration chromatography. The isolated ?-amylase was immobilized by ionotropic gelation technique using gellan gum (GG). These microspheres were spherical with average particle size of 375.62±21.76 to 492.54±32.18 ?m. The entrapment efficiency of these ?-amylase loaded GG microspheres was found 74.76±1.32 to 87.64±1.52%. Characterization of ?-amylase-gellan gum microspheres was confirmed using FTIR and SEM analysis. The in vitro amylase release kinetic have been studied by various mathematical models that follow the Korsmeyer-Peppas model (R2=0.9804-0.9831) with anomalous (non-Fickian) diffusion release mechanism. PMID:25014636

Chakraborty, Samrat; Jana, Sougata; Gandhi, Arijit; Sen, Kalyan Kumar; Zhiang, Wang; Kokare, Chandrakant

2014-09-01

15

Cytotoxicity of sophorolipid-gellan gum-gold nanoparticle conjugates and their doxorubicin loaded derivatives towards human glioma and human glioma stem cell lines  

NASA Astrophysics Data System (ADS)

Biocompatible gold nanoparticles were synthesized by using a naturally occurring gum-Gellan Gum-as a capping and reducing agent. These were further conjugated with sophorolipids which again were accessed through a biochemical transformation of a fatty acid. The cellular uptake of sophorolipid-conjugated gellan gum reduced gold nanoparticles and their cytotoxicity on human glioma cell line LN-229 and human glioma stem cell line HNGC-2 were investigated. Quite surprisingly even the simple sophorolipid-conjugated gellan gum reduced/capped gold nanoparticles showed greater efficacy in killing the glioma cell lines and, gratifyingly, the glioma stem cell lines also. The cytotoxic effects became more prominent once the anti cancer drug doxorubicin hydrochloride was also conjugated to these gold nanoparticles.Biocompatible gold nanoparticles were synthesized by using a naturally occurring gum-Gellan Gum-as a capping and reducing agent. These were further conjugated with sophorolipids which again were accessed through a biochemical transformation of a fatty acid. The cellular uptake of sophorolipid-conjugated gellan gum reduced gold nanoparticles and their cytotoxicity on human glioma cell line LN-229 and human glioma stem cell line HNGC-2 were investigated. Quite surprisingly even the simple sophorolipid-conjugated gellan gum reduced/capped gold nanoparticles showed greater efficacy in killing the glioma cell lines and, gratifyingly, the glioma stem cell lines also. The cytotoxic effects became more prominent once the anti cancer drug doxorubicin hydrochloride was also conjugated to these gold nanoparticles. Electronic supplementary information (ESI) available: Confocal Z-stacking images of Texas Red Conjugated SL-GG-Au NPs, thermogravimetic analysis of DOX-SL-GG-Au-NPs and SL-GG-AuNPs, and time-dependent fluorescence spectra of DOX-SL-GG-Au NPs. See DOI: 10.1039/c0nr00598c

Dhar, Sheetal; Reddy, E. Maheswara; Prabhune, Asmita; Pokharkar, Varsha; Shiras, Anjali; Prasad, B. L. V.

2011-02-01

16

Microfabricated photocrosslinkable polyelectrolyte-complex of chitosan and methacrylated gellan gum.  

PubMed

Chitosan (CHT) based polyelectrolyte complexes (PECs) have been receiving great attention for tissue engineering approaches. These hydrogels are held together by ionic forces and can be disrupted by changes in physiological conditions. In this study, we present a new class of CHT-based PEC hydrogels amenable to stabilization by chemical crosslinking. The photocrosslinkable anionic methacrylated gellan gum (MeGG) was complexed with cationic CHT and exposed to light, forming a PEC hydrogel. The chemical characterization of the photocrosslinkable PEC hydrogel by Fourier transform infrared spectroscopy (FTIR) revealed absorption peaks specific to the raw polymers. A significantly higher swelling ratio was observed for the PEC hydrogel with higher CHT content. The molecular interactions between both polysaccharides were evaluated chemically and microscopically, indicating the diffusion of CHT to the interior of the hydrogel. We hypothesized that the addition of MeGG to CHT solution first leads to a membrane formation around MeGG. Then, migration of CHT inside the MeGG hydrogel occurs to balance the electrostatic charges. The photocrosslinkable feature of MeGG further allowed the formation of cell-laden microscale hydrogel units with different shapes and sizes. Overall, this system is potentially useful for a variety of applications including the replication of microscale features of tissues for modular tissue engineering. PMID:23293429

Coutinho, Daniela F; Sant, Shilpa; Shakiba, Mojdeh; Wang, Ben; Gomes, Manuela E; Neves, Nuno M; Reis, Rui L; Khademhosseini, Ali

2012-09-01

17

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

PubMed

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

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

2014-04-01

18

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

PubMed

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

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

2014-11-26

19

Microencapsulation of Lactobacillus helveticus and Lactobacillus delbrueckii using alginate and gellan gum.  

PubMed

Sodium alginate (SA) at 2% (w/v) and low acylated gellan gum (LAG) at 0.2% (w/v) were used to microencapsulate Lactobacillus helveticus and Lactobacillus delbrueckii spp lactis by employing the internal ionic gelation technique through water-oil emulsions at three different stirring rates: 480, 800 and 1200 rpm. The flow behavior of the biopolymer dispersions, the activation energy of the emulsion, the microencapsulation efficiency, the size distribution, the microcapsules morphology and the effect of the stirring rate on the culture viability were analyzed. All of the dispersions exhibited a non-Newtonian shear-thinning flow behavior because the apparent viscosity decreased in value when the shear rate was increased. The activation energy was calculated using the Arrhenius-like equation; the value obtained for the emulsion was 32.59 kJ/mol. It was observed that at 400 rpm, the microencapsulation efficiency was 92.83%, whereas at 800 and 1200 rpm, the stirring rates reduced the efficiency to 15.83% and 4.56%, respectively, evidencing the sensitivity of the microorganisms to the shear rate (13.36 and 20.05 s(-1)). Both optical and scanning electron microscopy (SEM) showed spherical microcapsules with irregular topography due to the presence of holes on its surface. The obtained size distribution range was modified when the stirring rate was increased. At 400 rpm, bimodal behavior was observed in the range of 20-420 ?m; at 800 and 1200 rpm, the behavior became unimodal and the range was from 20 to 200 ?m and 20 to 160 ?m, respectively. PMID:23987441

Rosas-Flores, Walfred; Ramos-Ramírez, Emma Gloria; Salazar-Montoya, Juan Alfredo

2013-10-15

20

Baclofen novel gastroretentive extended release gellan gum superporous hydrogel hybrid system: in vitro and in vivo evaluation.  

PubMed

Abstract Baclofen is a centrally acting skeletal muscle relaxant with a short elimination half-life, which results in frequent daily dosing and subsequent poor patient compliance. The narrow absorption window of baclofen in the upper gastrointestinal tract limits its formulation as extended release dosage forms. In this study, baclofen extended release superporous hydrogel (SPH) systems, including conventional SPH, SPH composite and SPH hybrid (SPHH), were prepared aiming to increase the residence of baclofen at its absorption window. The applicability of different polymers, namely, gellan gum, guar gum, polyvinyl alcohol and gelatin, was investigated in preparation of SPHH systems. The prepared SPH systems were evaluated regarding weight and volume swelling ratio, porosity, mechanical properties, incorporation efficiency, degree of erosion and drug release. In vivo assessment was performed in dogs to evaluate gastric residence time by X-ray studies. In addition, the oral bioavailability of baclofen relative to commercially available Lioresal® immediate release tablets was also investigated. The novel baclofen gellan SPHH cross linked with calcium chloride was characterized by optimum mechanical properties, acceptable swelling properties as well as extended drug release. It also exhibited a prolonged plasma profile when compared to twice daily administered Lioresal®. PMID:24786486

El-Said, Ibrahim A; Aboelwafa, Ahmed A; Khalil, Rawia M; Elgazayerly, Omaima N

2014-04-30

21

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

PubMed

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

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

2012-09-01

22

Optimization of a chromatographic stationary phase based on gellan gum using central composite design.  

PubMed

To develop a new stationary phase of easy production, low cost, biocompatible, biodegradable and low unspecific adsorption, a three-dimensional network was prepared by combining the natural polysaccharide of gellan with divalent cations. The stability of this cation exchange chromatographic matrix was optimized by using an experimental design tool. The optimal conditions proposed for the gellan gel formulation were 48mM ZnSO4, 0% DMF, 25°C, 0.75% gellan and 0.5h. The applicability of gellan matrix was tested by chromatographic assays with three model proteins (bovine serum albumin (BSA), ?-chymotripsin and lysozyme). The results showed that the retention occurred in function of the net charge of each protein in MES buffer pH 6.2 and the elution was performed by increase of ionic strength to 750mM NaCl in MES buffer pH 6.2. Lysozyme was the more retained protein due to its positive charge more effective than ?-chymotripsin, while BSA did not interact with the matrix due to its negative charge at these conditions. Dynamic binding capacity assays were accomplished to characterize this matrix and to compare with commercial resins. The values of dynamic binding capacity from gellan gel were 3.9mg/mL and 17.4mg/mL, at 10% and 50% of breakthrough, respectively. In this way, gellan gel might be a promising chromatographic matrix to explore ionic interactions and to be applied in different purification strategies, getting the best benefit from its use at low cost. PMID:24657410

Gonçalves, A I C; Rocha, L A; Dias, J M L; Passarinha, L A; Sousa, A

2014-04-15

23

Identification of the pgmG Gene, Encoding a Bifunctional Protein with Phosphoglucomutase and Phosphomannomutase Activities, in the Gellan Gum-Producing Strain Sphingomonas paucimobilis ATCC 31461  

Microsoft Academic Search

The pgmG gene of Sphingomonas paucimobilis ATCC 31461, the industrial gellan gum-producing strain, was cloned and sequenced. It encodes a 50,059-Da polypeptide that has phosphoglucomutase (PGM) and phospho- mannomutase (PMM) activities and is 37 to 59% identical to other bifunctional proteins with PGM and PMM activities from gram-negative species, including Pseudomonas aeruginosa AlgC. Purified PgmG protein showed a marked preference

PAULA A. VIDEIRA; LUISA L. CORTES; ARSENIO M. FIALHO; I. Sa-Correia

2000-01-01

24

Optimization of nutrients for gellan gum production by Sphingomonas paucimobilis ATCC31461 in molasses based medium using response surface methodology  

Microsoft Academic Search

A molasses based medium for the production of gellan by Sphingomonas paucimobilis ATCC-31461 was developed. Placket–Burman design criterion was applied to study the effect of various nutrient supplements on gellan production using molasses. Among the 20 variables tested, molasses, tryptone, casaminoacid, disodium hydrogen orthophosphate and manganese chloride showed significant effect on gellan production. A central composite design was applied to

R. M. Banik; A. Santhiagu; S. N. Upadhyay

2007-01-01

25

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

PubMed

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

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

26

Injectable self-gelling composites for bone tissue engineering based on gellan gum hydrogel enriched with different bioglasses.  

PubMed

Hydrogels of biocompatible calcium-crosslinkable polysaccharide gellan gum (GG) were enriched with bioglass particles to enhance (i) mineralization with calcium phosphate (CaP); (ii) antibacterial properties and (iii) growth of bone-forming cells for future bone regeneration applications. Three bioglasses were compared, namely one calcium-rich and one calcium-poor preparation both produced by a sol-gel technique (hereafter referred to as A2 and S2, respectively) and one preparation of composition close to that of the commonly used 45S5 type (hereafter referred to as NBG). Incubation in SBF for 7 d, 14 d and 21 d caused apatite formation in bioglass-containing but not in bioglass-free samples, as confirmed by FTIR, XRD, SEM, ICP-OES, and measurements of dry mass, i.e. mass attributable to polymer and mineral and not water. Mechanical testing revealed an increase in compressive modulus in samples containing S2 and NBG but not A2. Antibacterial testing using biofilm-forming meticillin-resistant staphylococcus aureus (MRSA) showed markedly higher antibacterial activity of samples containing A2 and S2 than samples containing NBG and bioglass-free samples. Cell biological characterization using rat mesenchymal stem cells (rMSCs) revealed a stimulatory effect of NBG on rMSC differentiation. The addition of bioglass thus promotes GG mineralizability and, depending on bioglass type, antibacterial properties and rMSC differentiation. PMID:25065649

Douglas, Timothy E L; Piwowarczyk, Wojciech; Pamula, Elzbieta; Liskova, Jana; Schaubroeck, David; Leeuwenburgh, Sander C G; Brackman, Gilles; Balcaen, Lieve; Detsch, Rainer; Declercq, Heidi; Cholewa-Kowalska, Katarzyna; Dokupil, Agnieszka; Cuijpers, Vincent M J I; Vanhaecke, Frank; Cornelissen, Ria; Coenye, Tom; Boccaccini, Aldo R; Dubruel, Peter

2014-08-01

27

Improvement in Production and Quality of Gellan Gum by Sphingomonas paucimobilis Under High Dissolved Oxygen Tension Levels  

Microsoft Academic Search

The effect of agitation rate and dissolved oxygen tension (DOT) on growth and gellan production by Sphingomonas paucimobilis was studied. Higher cell growth of 5.4 g l?1 was?obtained at 700 rpm but maximum gellan (15 g l?1) was produced at 500 rpm. DOT levels above 20% had no effect on cell growth but gellan yield was increased to 23 g l?1 with increase in DOT level to 100%.

R. M. Banik; A. Santhiagu

2006-01-01

28

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

PubMed

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

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

2015-04-01

29

Optimization of gellan gum production by Sphingomonas paucimobilis ATCC 31461 with nonionic surfactants using central composite design.  

PubMed

The effect of nonionic surfactants on gellan production by Sphingomonas paucimobilis was studied by the addition of 0.5, 0.75, 1.0, 1.25 and 1.5 g/l surfactants to shake flask culture. The nonionic surfactants Tween 80, Tween 40 and Triton X-100 improved gellan production by S. paucimobilis, and the maximum yield (10.44 g/l) was obtained with Triton X-100 at 0.75 g/l compared with that of the control fermentation (8.63 g/l) without surfactant. The DO profiles associated with gellan production in a 5-l laboratory fermentor showed higher oxygen and mass transfers during fermentation with surfactant than during control fermentation without surfactant. The addition of surfactant also resulted in a polymer with high viscosity as manifested by its lower acetyl content, than that obtained by control fermentation. A central composite design (CCD) was used to determine the maximum gellan production at optimum values for three process parameters (Triton X-100 concentration, pH, and temperature) each at five levels in a laboratory fermentor. The maximum gellan yield (14.62 g/l) was obtained in a 5-l laboratory fermentor with 1.0 g/l Triton X-100 and at pH 6.0 and temperature 29.6 degrees C. Further studies on the effects of agitation and DOT level demonstrated that the surfactants enhanced oxygen transfer resulting in higher gellan production (27.86 g/l) at higher agitation speed (1000 rpm) and 100% DOT level. PMID:18397769

Arockiasamy, Santhiagu; Banik, Rathindra Mohan

2008-03-01

30

Fermentative production of gellan using Sphingomonas paucimobilis  

Microsoft Academic Search

The biopolymer gellan belongs to the family of microbial polysaccharides having a wide range of industrial applications. Attempts were made to produce gellan gum in submerged fermentation (SmF) using Sphingomonas paucimobilis ATCC 31461. Studies on the nutritional requirements for optimal exopolysaccharide production in a salt based synthetic medium revealed soluble starch (20 g\\/l) as the best carbon source and tryptone

K. Madhavan Nampoothiri; Reeta Rani Singhania; C Sabarinath; Ashok Pandey

2003-01-01

31

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

PubMed Central

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

Abbas, Zaheer; Marihal, Sachin

2014-01-01

32

Generation of composites for bone tissue-engineering applications consisting of gellan gum hydrogels mineralized with calcium and magnesium phosphate phases by enzymatic means.  

PubMed

Mineralization of hydrogels, desirable for bone regeneration applications, may be achieved enzymatically by incorporation of alkaline phosphatase (ALP). ALP-loaded gellan gum (GG) hydrogels were mineralized by incubation in mineralization media containing calcium and/or magnesium glycerophosphate (CaGP, MgGP). Mineralization media with CaGP:MgGP concentrations 0.1:0, 0.075:0.025, 0.05:0.05, 0.025:0.075 and 0:0.1 (all values mol/dm(3) , denoted A, B, C, D and E, respectively) were compared. Mineral formation was confirmed by IR and Raman, SEM, ICP-OES, XRD, TEM, SAED, TGA and increases in the the mass fraction of the hydrogel not consisting of water. Ca was incorporated into mineral to a greater extent than Mg in samples mineralized in media A-D. Mg content and amorphicity of mineral formed increased in the order A??B?>?C?>?D, but were significantly higher for samples mineralized in medium E. The attachment and vitality of osteoblastic MC3T3-E1 cells were higher on samples mineralized in media B-E (containing Mg) than in those mineralized in medium A (not containing Mg). All samples underwent degradation and supported the adhesion of RAW 264.7 monocytic cells, and samples mineralized in media A and B supported osteoclast-like cell formation. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24616374

Douglas, Timothy E L; Krawczyk, Grzegorz; Pamula, Elzbieta; Declercq, Heidi A; Schaubroeck, David; Bucko, Miroslaw M; Balcaen, Lieve; Van Der Voort, Pascal; Bliznuk, Vitaliy; van den Vreken, Natasja M F; Dash, Mamoni; Detsch, Rainer; Boccaccini, Aldo R; Vanhaecke, Frank; Cornelissen, Maria; Dubruel, Peter

2014-02-21

33

Characterization of the ugpG gene encoding a UDP-glucose pyrophosphorylase from the gellan gum producer Sphingomonas paucimobilis ATCC 31461  

Microsoft Academic Search

The ugpG gene, which codes for a UDP-glucose pyrophosphorylase (UGP) (or glucose-1-phosphate uridylyltransferase; EC 2.7.7.9) in Sphingomonas paucimobilis ATCC 31461, was cloned and sequenced. This industrial strain produces the exopolysaccharide gellan, a new commercial gelling agent, and the ugpG gene may convert glucose-1-phosphate into UDP-glucose in the gellan biosynthetic pathway. The ugpG gene is capable of restoring the capacity of

A. R. Marques; P. B. Ferreira; I. Sá-Correia; A. M. Fialho

2003-01-01

34

21 CFR 172.665 - Gellan gum.  

Code of Federal Regulations, 2010 CFR

...to a mixed potassium, sodium, calcium, and magnesium salt. The polysaccharide...into a solution of 10-percent calcium chloride. A tough worm-like gel will...test (i), 0.50 gram of sodium chloride is added. The solution is...

2010-04-01

35

21 CFR 172.665 - Gellan gum.  

Code of Federal Regulations, 2011 CFR

...with isopropyl alcohol. It is composed of tetrasaccharide repeat units, each containing one molecule of rhamnose and glucuronic acid, and two molecules of glucose. The glucuronic acid is neutralized to a mixed potassium, sodium,...

2011-04-01

36

21 CFR 172.665 - Gellan gum.  

Code of Federal Regulations, 2012 CFR

...with isopropyl alcohol. It is composed of tetrasaccharide repeat units, each containing one molecule of rhamnose and glucuronic acid, and two molecules of glucose. The glucuronic acid is neutralized to a mixed potassium, sodium,...

2012-04-01

37

21 CFR 172.665 - Gellan gum.  

Code of Federal Regulations, 2014 CFR

...with isopropyl alcohol. It is composed of tetrasaccharide repeat units, each containing one molecule of rhamnose and glucuronic acid, and two molecules of glucose. The glucuronic acid is neutralized to a mixed potassium, sodium,...

2014-04-01

38

21 CFR 172.665 - Gellan gum.  

Code of Federal Regulations, 2013 CFR

...with isopropyl alcohol. It is composed of tetrasaccharide repeat units, each containing one molecule of rhamnose and glucuronic acid, and two molecules of glucose. The glucuronic acid is neutralized to a mixed potassium, sodium,...

2013-04-01

39

Nicotine Gum  

MedlinePLUS

Nicotine chewing gum is used to help people stop smoking cigarettes. Nicotine chewing gum should be used together with a smoking cessation ... Nicotine gum is used by mouth as a chewing gum and should not be swallowed. Follow the directions ...

40

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

NASA Astrophysics Data System (ADS)

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.

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

2013-06-01

41

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

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

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

42

Self-structuring foods based on acid-sensitive low and high acyl mixed gellan systems to impact on satiety  

PubMed Central

This study investigated the in vitro acid-induced gelation of mixed systems of two biopolymers; low acyl and high acyl gellan gum. Rheological and texture analysis showed that these mixed gels displayed textures that lay between the material properties exhibited for the low and high acyl variants. DSC analysis showed that mixtures of the low acyl and high acyl forms exhibit two separate conformational transitions at temperatures coincident with each of the individual biopolymers. Various metabolically relevant pH environments and hydrocolloid concentrations were investigated. These resulted in very different acid gelled structures, which were characterised by texture analysis. The structures of the acid gels were shown to depend upon the pH, hydrocolloid concentration and proportion of each biopolymer used during their production. A selection of these mixed gellan structures were assessed post-production in terms of their response to prolonged exposure to an acidic (pH 1), stomach-like, environment. This resulted in a significant increase in the gel strength, regardless of the biopolymer proportions. The high acyl gellan was less acid-sensitive, and subsequently no evidence of acid gelation was observed with high acyl gellan at a proportion greater than 60% of the total biopolymer. The findings presented here demonstrate that structuring as well as de-structuring of mixed gellan acid gels can be controlled in acidic environments similar to those that are present in the stomach after food consumption. PMID:24882914

Bradbeer, Jennifer F.; Hancocks, Robin; Spyropoulos, Fotios; Norton, Ian T.

2014-01-01

43

Synthesis, characterization and evaluation of methacrylamide grafted gellan as sustained release tablet matrix.  

PubMed

In the present study, the microwave induced synthesis of polymethacrylamide-grafted-gellan gum (PMaa-g-GG) was carried out by free radical initiation using cerric (IV) ammonium nitrate (CAN) as redox initiator. Concentrations of methacrylamide (Maa), CAN and microwave irradiation time were taken as variable synthetic parameters. The modified polysaccharide obtained from different synthetic conditions was then characterized by FTIR, CHN analysis, DSC and powder X-ray diffraction. The yield and extent of grafting were assessed by determining percentage grafting, percentage grafting efficiency, percentage conversion and these were correlated with elemental analysis. The acute oral toxicity study of modified polysaccharide was performed as per OECD guideline. Histological comparison of different organs between control and test animal showed no significant difference. Sustained release tablets of diclofenac sodium (DS) were prepared with modified gellan. In vitro dissolution study showed the tablets were capable of releasing the drug over a period of 8 h. PMID:25316428

Nandi, Gouranga; Patra, Poushali; Priyadarshini, Rosy; Kaity, Santanu; Ghosh, Lakshmi Kanta

2015-01-01

44

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

PubMed Central

The dairy industry produces large quantities of whey as a by-product of cheese production and is increasingly 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 31461 in media containing glucose, lactose (5 to 30 g/liter), and sweet cheese whey. We found that altering the growth medium can markedly affect the polysaccharide yield, acyl substitution level, polymer rheological properties, and susceptibility to degradation. Depression of gellan production from lactose compared with gellan production from glucose (approximately 30%) did not appear to occur at the level of synthesis of sugar nucleotides, which are the donors of monomers used for biosynthesis of the repetitive tetrasaccharide unit of gellan. The lactose-derived biopolymer had the highest total acyl content; the glucose- and whey-derived gellans had similar total acyl contents but differed markedly in their acetate and glycerate levels. Rheological studies revealed how the functionality of a gellan polysaccharide is affected by changes in the acyl substitution. PMID:10347031

Fialho, Arsénio M.; Martins, Lígia O.; Donval, Marie-Lucie; Leitão, Jorge H.; Ridout, Michael J.; Jay, Andrew J.; Morris, Victor J.; Sá-Correia, Isabel

1999-01-01

45

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

NASA Astrophysics Data System (ADS)

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.

Wu, Chien-Chen; Chen, Dong-Hwang

2012-06-01

46

Nanometric organisation in blends of gellan/xyloglucan hydrogels.  

PubMed

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

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

47

Thermoresponsive magnetic nanoparticle--aminated guar gum hydrogel system for sustained release of doxorubicin hydrochloride.  

PubMed

Hydrogel based sustained drug delivery system has evolved as an immense treatment method for solid tumors over the past few decades with long term theranostic ability. Here, we synthesized an injectable hydrogel system comprising biocompatible aminated guar gum, Fe3O4-ZnS core-shell nanoparticles and doxorubicin hydrochloride. We show that amination of guar gum resulted in attraction of water molecules thereby forming the hydrogel without using toxic crosslinking agents. Hydrogel formation was observed at 37°C and is stable up to 95°C. The prepared hydrogel is also stable over a wide pH range. The in vitro studies show that the maximum de-gelation and drug release up to 90% can be achieved after 20 days of incubation. Studies reveal that the drug and the core-shell nanoparticles can be released slowly from the hydrogel to provide the healing and diagnosis of the solid tumor thereby avoiding several drug administrations and total excision of organs. PMID:24906777

Murali, Ragothaman; Vidhya, Ponraj; Thanikaivelan, Palanisamy

2014-09-22

48

Oral sustained delivery of paracetamol from in situ-gelling gellan and sodium alginate formulations.  

PubMed

The purpose of this study was to evaluate the potential for the oral sustained delivery of paracetamol of two formulations with in situ gelling properties. Oral administration of aqueous solutions of either gellan gum (1.0%, w/v) or sodium alginate (1.5%, w/v) containing calcium ions in complexed form resulted in the formation of gel depots in rabbit and rat stomachs as a consequence of the release of the calcium ions in the acidic environment. In vitro studies demonstrated diffusion-controlled release of paracetamol from the gels over a period of 6h. The bioavailability of paracetamol from the gels formed in situ in the stomachs of rabbits following oral administration of the liquid formulations was similar to that of a commercially available suspension containing an identical dose of paracetamol. PMID:12753753

Kubo, Wataru; Miyazaki, Shozo; Attwood, David

2003-06-01

49

Gum Disease  

MedlinePLUS

... out toothbrush can injure your gums. (Some toothbrush brands contain color indicators on the bristles to remind you to replace them when they become worn.) Eat a healthy diet. Avoid snacks and junk foods packed with sugar that plaque-causing bacteria love to feed on. Don't smoke! Cigarettes and ...

50

Gum Disease Symptoms  

MedlinePLUS

... Comprehensive Periodontal Evaluation Periodontal Treatments and Procedures Non-Surgical Periodontal Treatments Gum Graft Surgery Laser Treatment for Gum Disease Regenerative Procedures Dental Crown ...

51

Gum Graft Surgery  

MedlinePLUS

... Comprehensive Periodontal Evaluation Periodontal Treatments and Procedures Non-Surgical Periodontal Treatments Gum Graft Surgery Laser Treatment for Gum Disease Regenerative Procedures Dental Crown ...

52

Gum Disease and Women  

MedlinePLUS

... Comprehensive Periodontal Evaluation Periodontal Treatments and Procedures Non-Surgical Periodontal Treatments Gum Graft Surgery Laser Treatment for Gum Disease Regenerative Procedures Dental Crown ...

53

Flow behaviour of gellan sol with selected cations.  

PubMed

An understanding of the flow behaviour of the sols before gel formation is important for developing nutrient enriched gels. The influence of cations like CaCl2 (0.05 and 0.1 %, w/w) and FeSO4 (0.05 and 0.1 %, w/w) on the rheological properties of 1 % gellan sol (w/w) prior to gelling was investigated. The apparent viscosity, reported at a shear-rate of 100 s(-1), indicated that the gellan dispersion without any cation possessed lower values compared to other samples containing different cations. The Cross model provided the best fit (0.97???r???0.99, p???0.01) compared to moderate fitting to power law model (0.94???r???0.98). Among the different Cross model parameters, the zero-shear viscosity (?o) increased with the addition of CaCl2 and FeSO4, and with an increase in their concentrations. Zero-shear viscosity values were 0.46 Pas for gellan sol, 0.79 Pas for gellan with 0.05 % (w/w) CaCl2, 1.41 Pas for gellan with 0.1 % CaCl2, 3.85 Pas for gellan with 0.05 % FeSO4 and 4.33 Pas for gellan with 0.1 % FeSO4. An increase in cation concentration from 0.05 to 0.10 % (w/w) marginally increased the relaxation time (?) values indicating the development of more solid characteristics in the sol. PMID:25694746

Sharma, Shipra; Bhattacharya, Suvendu

2015-02-01

54

Chew that Gum  

NSDL National Science Digital Library

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.

Twin Cities Public Television, Inc.

2005-01-01

55

Ispaghula mucilage-gellan mucoadhesive beads of metformin HCl: development by response surface methodology.  

PubMed

Response surface methodology based on 3(2) factorial design was used to develop ispaghula (Plantago ovata F.) husk mucilage (IHM)-gellan gum (GG) mucoadhesive beads containing metformin HCl through Ca(2+)-ion cross-linked ionotropic-gelation technique for the use in oral drug delivery. GG to IHM ratio and cross-linker (CaCl2) concentration were investigated as independent variables. Drug encapsulation efficiency (DEE, %) and cumulative drug release after 10h (R10h, %) were analyzed as dependent variables. The optimized mucoadhesive beads (F-O) showed DEE of 94.24 ± 4.18%, R10h of 59.13 ± 2.27%. These beads were also characterized by SEM and FTIR analyses. The in vitro drug release from these beads showed controlled-release (zero-order) pattern with super case-II transport mechanism over 10h. The optimized beads showed pH-dependent swelling and good mucoadhesivity with the goat intestinal mucosa. The optimized IHM-GG mucoadhesive beads containing metformin HCl exhibited significant antidiabetic effect in alloxan-induced diabetic rats over 10h. PMID:24702916

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

2014-07-17

56

The effect of agitation and aeration on the synthesis and molecular weight of gellan in batch cultures of Sphingomonas paucimobilis  

Microsoft Academic Search

The effects of agitation and aeration upon synthesis and molecular weight of the biopolymer gellan were systematically investigated in batch fermenter cultures of the bacterium, Sphingomonas paucimobilis. High aeration rates and vigorous agitation enhanced growth of S. paucimobilis. Although gellan formation occurred mainly in parallel with cell growth, the increase in cells able to synthesise gellan did not always lead

Ioannis Giavasis; Linda M. Harvey; Brian McNeil

2006-01-01

57

Gum Disease Risk Assessment Test  

MedlinePLUS

... Comprehensive Periodontal Evaluation Periodontal Treatments and Procedures Non-Surgical Periodontal Treatments Gum Graft Surgery Laser Treatment for Gum Disease Regenerative Procedures Dental Crown ...

58

Occurrence, production, and applications of gellan: current state and perspectives  

Microsoft Academic Search

Bacterial exopolysaccharides (EPS) are products of biotechnology that are of high interest due to their rheological properties.\\u000a This is the case of sphingans, a group of structurally related EPS secreted by members of the genus Sphingomonas. Among these, gellan is a multifunctional gelling agent produced in high yields by the non-pathogenic strain Sphingomonas elodea ATCC 31461. In its native form,

Arsenio M. Fialho; Leonilde M. Moreira; Ana Teresa Granja; Alma O. Popescu; Karen Hoffmann; Isabel Sá-Correia

2008-01-01

59

Biotechnology of the Bacterial Gellan Gum: Genes and Enzymes of the Biosynthetic Pathway  

Microsoft Academic Search

Bacterial exopolysaccharides (EPS) are a diverse and remarkably versatile class of materials that have potential applications\\u000a in virtually all sectors of modern industry and economy. Currently, many biopolymers are still in the developmental stage,\\u000a but important applications are beginning to emerge in the areas of food production and biomedicine. A few bacterial EPS can\\u000a directly replace synthetically derived material in

Arsénio M. Fialho; Leonilde M. Moreira; Ana Teresa Granja; Karen Hoffmann; Alma Popescu; Isabel Sá-Correia

60

Evaluation of gellan gum fluid gels as modified release oral liquids.  

PubMed

Oral liquids are often preferred for drug administration to patients for whom swallowing is difficult, however, formulating modified release versions can be challenging. A potential route to achieve modified release in oral liquids is by using fluid (sheared) gels formed by introducing a shear field during gelation in gel-forming biopolymers. These fluid gels can act as pourable viscoelastic fluids but retain true gel micro/nano structure. Here, we have demonstrated that fluid gels have potential as paediatric oral liquids preventing release of ibuprofen in simulated gastric fluid. Subsequent release at pH 7.4 was affected by the duration of exposure and magnitude of acid pH with a linear relationship between onset of release and the preceding acidic exposure duration. Delayed release was a result of increasing gel stiffness, a consequence of the acidity of the initial release media and exposure time. A much faster release rate was measured when exposure time in acid was 10 min compared with 60 min. This study highlights the potential to design fluid gels that are tuned to have a specified stiffness at a particular pH and exposure time. This could enable the preparation oral liquids with modified release behaviour. PMID:25169076

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

2014-11-20

61

DSC and FTIR studies on Gellan and Polyvinyl alcohol (PVA) blend films  

Microsoft Academic Search

Homopolymer films of Gellan and polyvinyl alcohol (PVA) and blended films were prepared by a solution casting method from a polymer solution in water of Gellan and PVA using glycerol as plasticizer. The films were studied for thermal characteristics by differential scanning calorimetry, for intermolecular interactions by Fourier transform infrared spectroscopy and for the mechanical properties of tear strength, tensile

S. R Sudhamani; M. S Prasad; K Udaya Sankar

2003-01-01

62

Organization of genes required for gellan polysaccharide biosynthesis in Sphingomonas elodea ATCC 31461  

Microsoft Academic Search

Sphingomonas elodea ATCC 31461 produces gellan, a capsular polysaccharide that is useful as a gelling agent for food and microbiological media. Complementation of nonmucoid S. elodea mutants with a gene library resulted in identification of genes essential for gellan biosynthesis. A cluster of 18 genes spanning 21 kb was isolated. These 18 genes are homologous to genes for synthesis of sphingan

Nancy E. Harding; Yamini N. Patel; Russell J. Coleman

2004-01-01

63

Gum Disease in Children  

MedlinePLUS

... patients generally form very little dental plaque or calculus. Generalized aggressive periodontitis may begin around puberty and ... the gums and heavy accumulations of plaque and calculus. Eventually it can cause the teeth to become ...

64

The Effect of Three Gums on the Retrogradation of Indica Rice Starch  

PubMed Central

Retrograded starch (RS3) was produced from indica rice starch with three kinds of gums (konjac glucomannan, KGM; carrageenan, CA, USA; and gellan, GA, USA) by autoclaving, respectively, and the effect of the gums on the retrogradation behavior of starch was estimated. The influences of polysaccharide concentration, sodium chloride concentration, autoclaving time, refrigerated time, and pH value on RS3 formation were discussed. Except for sodium chloride’s persistent restraint on RS3, the others all forced RS3 yields higher at first, but lowered it after the peak value. The influencing sequence of these impact factors was: sodium chloride concentration > polysaccharide concentration > autoclaving time > refrigerated time > pH value. The results also proved that in the three gums, KGM plays the most significant role in RS3 changing. It was concluded that the incorporation of each of these three gums into starch, especially KGM, results in an increase or decrease of RS3 under different conditions. This phenomenon could be taken into consideration when developing starchy food with appropriate amount of RS3. PMID:22822444

Song, Rukun; Huang, Min; Li, Bin; Zhou, Bin

2012-01-01

65

The effect of thermal history on the elasticity of K-type gellan gels.  

PubMed

Elasticity of potassium type gellan gels prepared at different thermal histories was examined using dynamic viscoelastic measurements. The storage Young's modulus E' decreased with increasing cooling rate during gelation. Once gel formation occurred, thermal history at lower temperature did not influence the elastic modulus and thermal stability of the gellan gels. On the other hand, thermal history around gelation temperature influenced strongly the elastic modulus and thermal stability of resulting gels. When the gellan solution was kept for a certain time before cooling at a temperature near the gelation temperature, it was found that gels with higher elastic modulus and thermal stability were formed. PMID:25256474

Nitta, Yoko; Yoshimura, Miki; Nishinari, Katsuyoshi

2014-11-26

66

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

PubMed

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

Murillo-Martínez, María M; Tecante, Alberto

2014-08-01

67

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

PubMed Central

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

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

2012-01-01

68

Trigonella foenum-graecum L. seed mucilage-gellan mucoadhesive beads for controlled release of metformin HCl.  

PubMed

Fenugreek (Trigonella foenum-graecum L.) seed mucilage (FSM)-gellan gum (GG) mucoadhesive beads containing metformin HCl for oral use were developed through ionotropic-gelation technique. Effects of GG to FSM ratio and cross-linker (CaCl2) concentration on the drug encapsulation efficiency (DEE, %), and cumulative drug release after 10h (R10h, %) of ionotropically-gelled FSM-GG mucoadhesive beads containing metformin HCl were optimized by 3(2) factorial design. The optimized mucoadhesive beads showed DEE of 92.53 ± 3.85% and R10h of 55.28 ± 1.58% and mean diameter of 1.62 ± 0.22 mm. The in vitro metformin HCl release from these ionotropically-gelled FSM-GG beads was prolonged over 10h and followed zero-order model with super case-II transport mechanism. The optimized mucoadhesive beads also exhibited pH-dependent swelling, good mucoadhesivity with biological mucosal membrane and significant hypoglycemic effect in alloxan-induced diabetic rats over prolonged period after oral administration. PMID:24702915

Nayak, Amit Kumar; Pal, Dilipkumar

2014-07-17

69

Retention of ethyl butyrate by gellan gels in the presence of potassium ions  

Microsoft Academic Search

The air\\/biopolymer partition coefficient (K) and percentage of retention (R%) of ethyl butyrate (400ppm) added to gellan gels were determined, using static headspace gas chromatography. Potassium chloride (40–120mM) was used to induce gellan gelation. When 5g of sample were left to equilibrate at 37°C for 2 and 24h, the coefficient values initially decreased with salt concentration to a certain value

Vasiliki Evageliou; Panagiota Galanaki; Chryssavgi Gardeli; Michael Komaitis

2011-01-01

70

Biosynthesis of a thermostable gellan lyase by newly isolated and characterized strain of Geobacillus stearothermophilus 98  

Microsoft Academic Search

The thermophilic strain able to degrade gellan was isolated from Bulgarian hot spring. According to its morphological and biochemical properties and by partial sequencing of its 16S rDNA, it was classified as Geobacillus stearothermophilus. It grew in a synthetic medium with gellan as the only carbon source with a specific growth rate of 0.69 h?1 and generation time of 60 min. The

Anna Derekova; Carsten Sjøholm; Rossica Mandeva; Lilia Michailova; Margarita Kambourova

2006-01-01

71

Carbamoylethylation of Cassia tora gum  

Microsoft Academic Search

Carbamoylethylation of Cassia tora gum was carried out with acrylamide in presence of sodium hydroxide under different reaction conditions. Variables studied were concentration of sodium hydroxide, acrylamide, Cassia tora gum as well as reaction temperature and time. The nitrogen content, carboxyl content and total ether content were determined. The optimum condition for preparing carbamoylethyl Cassia tora gum (%N=3.24) comprised concentration

Brij Raj Sharma; Vineet Kumar; P. L. Soni

2003-01-01

72

A new strategy to enhance gellan production by two-stage culture in Sphingomonas paucimobilis.  

PubMed

The effects of different initial sucrose concentrations and temperatures on gellan biosynthesis by Sphingomonas paucimobilis ATCC 31461 were investigated. Lower sucrose concentrations and higher temperatures were favorable for cell growth. Higher sucrose concentrations and lower temperatures promoted gellan production but retarded cell growth. Based on these results, a two-stage culture strategy was developed to improve gellan production. During the first 24 h, S. paucimobilis was cultured in a pulse fed-batch mode with an initial sucrose concentration 10 g/L. Ten grams per liter of sucrose were added at 12 h and 24 h, and the temperature was controlled at 33 °C. Batch culture was performed, and the temperature was reduced to 28 °C to achieve a high gellan accumulation. The two-stage culture strategy achieved the highest gellan production (22.61 g/L) at 60 h that was 35.71% higher than the result of the best conventional batch operation (16.66 g/L). Meanwhile, high gellan yield was related to high UDPG-pyrophosphorylase activity and glucosyltransferase activity. PMID:23987418

Zhu, Guilan; Sheng, Long; Tong, Qunyi

2013-10-15

73

Gum and Heart Disease  

NSDL National Science Digital Library

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.

Science Update

2005-04-25

74

Guar Gum Slime  

NSDL National Science Digital Library

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.

2012-06-26

75

Gum Disease and Men  

MedlinePLUS

... becomes inflamed, infected, or affected by cancer, PSA levels rise. Research has shown that men with indicators of periodontal disease such as red, swollen or tender gums as well as prostatitis (inflammation of the prostate) have higher levels of PSA than men with only one of ...

76

Sphinganase, a new endoglycanase that cleaves specific members of the gellan family of polysaccharides.  

PubMed Central

A sporeforming gram-positive aerobic bacterium was isolated from soil and shown to secrete an endoglycanase that cleaves the tetrasaccharide backbone structure of specific members within the gellan family of related bacterial exopolysaccharides. We refer to these polysaccharides as sphingans. The structures of the sphingans differ by the type and position of side groups that are attached to the backbone. The new enzyme named sphinganase degrades welan, gellan, deacylated gellan, and polysaccharides S-88, S-7, and S-198. However, the enzyme does not attack rhamsan or polysaccharide NW11. Methods for growing the bacteria, isolating the enzyme, and assaying sphinganase activity are presented, and uses for the enzyme are proposed. Images PMID:8135511

Mikolajczak, M J; Thorne, L; Pollock, T J; Armentrout, R W

1994-01-01

77

Effects of inorganic cations on the rheology of aqueous welan, xanthan, gellan solutions and their mixtures.  

PubMed

The effects of different inorganic cations (Na(+), K(+), Ca(2+) and Al(3+)) on the rheological properties of single and mixture polysaccharide solutions have been systematically investigated. The apparent viscosity and viscoelasticity of welan solutions decrease with the addition of inorganic cations. Meanwhile, the addition of Al(3+) and K(+), respectively, enhances the apparent viscosity and viscoelasticity of xanthan and gellan solutions by promoting the gelation. The viscosity retention rate of welan/xanthan mixtures is higher than that of the single components in Na(+), K(+) and Ca(2+) solutions, and the viscosity retention rate of welan/gellan mixtures is higher than that of the single components in Ca(2+) solutions. The salt induced gelation expands the application for polysaccharides, and it is also believed that the method of combining welan and xanthan (or gellan) is an effective strategy to control the rheology and morphology of solutions in the presence of inorganic salts. PMID:25659683

Xu, Long; Dong, Mingzhe; Gong, Houjian; Sun, Mengjiao; Li, Yajun

2015-05-01

78

Conservation of Mass Gum Lab  

NSDL National Science Digital Library

Students develop and conduct an experiment using the law of conservation of mass to determine whether or not gum should be considered food. Students will compare the mass swallowed for sugar and sugar-free gum. This could be used to discuss solubility.

79

The Gum of Fagara xanthoxyloides  

Microsoft Academic Search

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

F. G. Torto

1957-01-01

80

The Trouble With Bubble Gum  

NSDL National Science Digital Library

Most students are totally unaware of the amount of sugar in bubble gum and don't know that they are literally eating sugar in huge amounts. In this chapter, the author is concerned with finding out what happens to the weight of gum when it is chewed, whic

Richard Konicek-Moran

2010-03-12

81

The Gum Nebula.  

NASA Technical Reports Server (NTRS)

A historical review of observations on the Gum Nebula is given together with a survey of knowledge on its size, emission features, and dynamics of expansion. The ultraviolet spectrum of Zeta Puppis is examined in terms of features caused by various absorption lines, and radio emission from Vela X is analyzed, together with the effects of nebular plasma on the propagation of radio pulses from pulsars in the Nebula. The density distribution and the possibility of being produced by the Vela X supernova are discussed.

Maran, S. P.

1971-01-01

82

Gum and Heart Disease  

NSDL National Science Digital Library

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.

American Association for the Advancement of Science (; )

2005-04-25

83

Gum chewing during pre-anesthetic fasting.  

PubMed

Many ad hoc fasting guidelines for pre-anesthetic patients prohibit gum chewing. We find no evidence that gum chewing during pre-anesthetic fasting increases the volume or acidity of gastric juice in a manner that increases risk, nor that the occasional associated unreported swallowing of gum risks subsequent aspiration. On the contrary, there is evidence that gum chewing promotes gastrointestinal motility and physiologic gastric emptying. Recommendations against pre-anesthetic gum chewing do not withstand scrutiny and miss an opportunity to enhance comfort and sense of wellbeing for patients awaiting anesthesia. Gum chewing during the pre-anesthetic nil per os (NPO) period would also permit the development of gum-delivered premedications and should be permitted in children old enough to chew gum safely. Gum chewing should cease when sedatives are given and all patients should be instructed to remove any chewing gum from the mouth immediately prior to anesthetic induction. PMID:22171675

Poulton, Thomas J

2012-03-01

84

The production of gellan exopolysaccharide with Sphingomonas paucimobilis E2 (DSM 6314)  

Microsoft Academic Search

A new screening technique was used to isolate the bacterium Sphingomonas paucimobilis E2 (DSM 6314), which produces the exopolysaccharide gellan. The productivity was found to be about four times higher than that of the industrially used strain Auromonas elodea (ATCC 31461) it was isolated from. The polysaccharide formation was found to be predominantly growth-related.

D. Lobas; S. Schumpe; W.-D. Deckwer

1992-01-01

85

Do It: Chew that Gum!  

NSDL National Science Digital Library

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.

Dragonfly TV

86

The comparison of rheological properties of aqueous welan gum and xanthan gum solutions.  

PubMed

Rheological properties of welan gum and xanthan gum solutions have been characterized systematically at various concentrations, temperatures and salinities. It is found that the viscoelasticity of welan gum is higher than that of xanthan gum at the same condition though the molecular weight of welan gum is lower. In view of this, welan gum will make a good performance in enhanced oil recovery, especially in high temperature and high salinity reservoirs. Network structure can be formed in solutions of welan gum and xanthan gum for the dynamic modulus has exponential relationship with the concentration. Moreover, the molecular aggregates of welan gum adopt a different arrangement with that of xanthan gum, adjacent double helices of welan gum arrange in parallel as the zipper model. The structure formed by zipper model is still stable in high temperature and high salinity. PMID:23218329

Xu, Long; Xu, Guiying; Liu, Teng; Chen, Yijian; Gong, Houjian

2013-01-30

87

Microwave assisted synthesis of acrylamide grafted locust bean gum and its application in drug delivery.  

PubMed

Acrylamide grafted copolymer of locust bean gum was prepared by microwave irradiation using ceric ammonium nitrate as redox initiator. The grafting process was optimized in terms of irradiation time, amount of initiator and acrylamide by using constant amount of native locust bean gum. The grafted gum was characterized by Fourier transform infrared spectroscopy (FT-IR), (13)C nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), X-ray diffraction study (XRD), differential scanning calorimetry (DSC), elemental analysis, contact angle, viscosity, molecular weight, swelling and biodegradability studies. The grafted gum was found to be biodegradable and non-toxic. It was further used to prepare controlled-release matrix tablet of buflomedil hydrochloride. The in vitro release profile of the tablet showed the rate controlling property of acrylamide grafted locust bean gum was similar to that of hydroxypropyl methylcellulose (HPMC-K15M). PMID:23987450

Kaity, Santanu; Isaac, Jinu; Kumar, P Mahesh; Bose, Anirbandeep; Wong, Tin Wui; Ghosh, Animesh

2013-10-15

88

'Radioactive' decay of chewing gum  

NSDL National Science Digital Library

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.

Kyle Nichols

89

Grewia gum as a potential aqueous film coating agent. I: Some physicochemical characteristics of fractions of grewia gum  

PubMed Central

Background: Grewia gum has received attention as a polymeric pharmaceutical excipient in the recent times, being employed as a suspending, film coating, mucoadhesive, and binding agent. The low aqueous solubility, however, has limited its characterization and application. Objective: The purpose of this study was to fractionate and evaluate some physicochemical properties of the gum. Materials and Methods: Aqueous dispersion of the gum was treated at 80°C for 30 min in the presence of sodium chloride and was subsequently fractionated by successively centrifuging it at 3445 rpm for 30 min. Skeletal density, solubility, particle size, and rheological as well as thermal characteristics of the fractions were evaluated. The 1H nuclear magnetic resonance (NMR) and near infrared (NIR) profiles of the fractions were also investigated. The solubility of the gum increased up to fourfold while the viscosity decreased from 244 to as low as70 cP at 40 rpm with some fractions. Results: Grewia gum and the fractions showed good thermal stability exhibiting no thermal events, but charred irreversibly at 297°C irrespective of the fraction. The molecular weight averages by weight and by number of the fractions were between 233,100 and 235,000. The 1H nuclear magnetic resonance (NMR) spectra showed broad peaks. The NMR and NIR spectra suggested the presence of –OH and –OCH3 functional groups in this gum. Conclusion: The fractionation improved solubility and facilitated further investigations on its characteristics that may have implication on its processing, application, and optimization as a potential pharmaceutical excipient. PMID:23559825

Ogaji, Ikoni J.; Okafor, Ignatius S.; Hoag, Stephen W.

2013-01-01

90

21 CFR 582.7330 - Gum arabic.  

Code of Federal Regulations, 2014 CFR

...AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Stabilizers § 582.7330 Gum arabic. (a) Product. Acacia (gum arabic). (b) Conditions of use. This substance is generally recognized as safe when used in accordance with...

2014-04-01

91

21 CFR 582.7330 - Gum arabic.  

Code of Federal Regulations, 2010 CFR

...AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Stabilizers § 582.7330 Gum arabic. (a) Product. Acacia (gum arabic). (b) Conditions of use. This substance is generally recognized as safe when used in accordance with...

2010-04-01

92

21 CFR 582.7330 - Gum arabic.  

Code of Federal Regulations, 2011 CFR

...AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Stabilizers § 582.7330 Gum arabic. (a) Product. Acacia (gum arabic). (b) Conditions of use. This substance is generally recognized as safe when used in accordance with...

2011-04-01

93

21 CFR 582.7330 - Gum arabic.  

Code of Federal Regulations, 2012 CFR

...AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Stabilizers § 582.7330 Gum arabic. (a) Product. Acacia (gum arabic). (b) Conditions of use. This substance is generally recognized as safe when used in accordance with...

2012-04-01

94

21 CFR 582.7330 - Gum arabic.  

Code of Federal Regulations, 2013 CFR

...AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Stabilizers § 582.7330 Gum arabic. (a) Product. Acacia (gum arabic). (b) Conditions of use. This substance is generally recognized as safe when used in accordance with...

2013-04-01

95

21 CFR 582.3336 - Gum guaiac.  

Code of Federal Regulations, 2010 CFR

... § 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...

2010-04-01

96

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2014 CFR

...Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several species of Astragalus gummifier Labillardiere, a shrub that grows wild in mountainous regions of the Middle East. (b) The...

2014-04-01

97

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2011 CFR

...Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several species of Astragalus gummifier Labillardiere, a shrub that grows wild in mountainous regions of the Middle East. (b) The...

2011-04-01

98

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2012 CFR

...Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several species of Astragalus gummifier Labillardiere, a shrub that grows wild in mountainous regions of the Middle East. (b) The...

2012-04-01

99

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2013 CFR

...Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several species of Astragalus gummifier Labillardiere, a shrub that grows wild in mountainous regions of the Middle East. (b) The...

2013-04-01

100

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2010 CFR

...Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several species of Astragalus gummifier Labillardiere, a shrub that grows wild in mountainous regions of the Middle East. (b) The...

2010-04-01

101

The biosynthesis of the exopolysaccharide gellan results in the decrease of Sphingomonas paucimobilis tolerance to copper  

Microsoft Academic Search

Although it is generally accepted that extracellular anionic polysaccharide-producing bacteria are more tolerant to toxic cations than the nonproducing strains, the gellan-producing Sphingomonas paucimobilis R40 was definitively less tolerant to sublethal concentrations of copper (Cu2+) than the nonproducing variant RP10. This nonmucoid strain was spontaneously obtained during the cultivation of mucoid R40. The two variants exhibited indistinguishable genome fingerprints with

João A. Richau; Denis Choquenet; Arsénio M. Fialho; Leonilde M. Moreira; Isabel Sá-Correia

1997-01-01

102

21 CFR 184.1339 - Guar gum.  

Code of Federal Regulations, 2010 CFR

...Drugs 3 2010-04-01 2009-04-01 true Guar gum. 184.1339 Section 184.1339 Food and...Specific Substances Affirmed as GRAS § 184.1339 Guar gum. (a) Guar gum is the natural substance obtained from the...

2010-04-01

103

Alginate beads of Captopril using galactomannan containing Senna tora gum, guar gum and locust bean gum.  

PubMed

Gastro-retentive Captopril loaded alginate beads were prepared by an ionotropic gelation method using sodium alginate in combination with natural gums containing galactomannans (Senna tora seed gum, guar gum and locust bean gum) in the presence of calcium chloride. The process variables such as concentration of sodium alginate/natural polymer, concentration of calcium chloride, curing time, stirring speed and drying condition were optimized. Prepared beads were evaluated for various parameters such as flow property, drug content and entrapment efficiency, size and shape, and swelling index. Surface morphology of the beads was studied using scanning electron microscopy. In vitro mucoadhesion and in vitro drug release studies were carried out on the prepared beads. From the entrapment efficiency and dissolution study, it was concluded that galactomannans in combination with sodium alginate show sustained release property. The bead formulation F4 prepared using combination of sodium alginate and guar gums in the ratio 2:1 showed satisfactory sustained release for 12h. The release of Captopril from the prepared beads was found to be controlled by the swelling of the polymer followed by drug diffusion through the swelled polymer and slow erosion of the beads. PMID:25720832

Pawar, Harshal A; Lalitha, K G; Ruckmani, K

2015-05-01

104

Does Your Chewing Gum Lose Its Flavor?  

NSDL National Science Digital Library

Each learner chews a piece of gum until it loses its flavor, and then leaves the gum to dry for several days. By weighing the gum before and after chewing, they can determine the amount of mass lost which corresponds to the amount of sugar in the gum. Learners are then asked to design their own experiment to answer a question of their choosing related to the activity. Learners can follow this with a related activity: "How much Sugar is in Bubble Gum?" Resource contains detailed suggestions to assist learners who are designing their own experiment. Time requirement is intended to be spread over several meetings.

2014-08-06

105

How Much Sugar Is in Bubble Gum?  

NSDL National Science Digital Library

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.

2014-09-18

106

TECHNICAL NOTE: The strengthening effect of guar gum on the yield stress of magnetorheological fluid  

NASA Astrophysics Data System (ADS)

In this paper we present a novel approach for producing obvious strengthening of the magnetorheological (MR) effect of MR fluids. Carbonyl iron powders coated with guar gum were used as magnetic particles in the MR fluid. Experimental results showed that inducing a guar gum coating not only greatly improved the sedimentation stability but also strengthened the yield stress of the MR fluid. An intermolecular force based model was proposed for explaining the strengthening effect.

Wu, Wei Ping; Zhao, Bin Yuan; Wu, Qing; Chen, LeSheng; Hu, Ke Ao

2006-08-01

107

TE activity gum drop atoms  

NSDL National Science Digital Library

This lesson has students building a model of lithium with gum drops and explaining where the model accurately represents the atom and where the model falls short. Enrichment exercises are included such as having groups of students play the parts of subatomic particles to model an atom in the gymnasium.

2006-01-01

108

Gummy vs. Gum (Number Pattern)  

NSDL National Science Digital Library

"In this lesson, students use gummy bears and sticks of gum to discover a number pattern and write an equation that describes it. This lesson should be conducted after students have worked with patterns and one- and two-step equations." from the Beacon Learning Center.

Beacon Learning Center

2009-10-13

109

Brief Report: Gum Chewing Affects Standardized Math Scores in Adolescents  

ERIC Educational Resources Information Center

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…

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

2012-01-01

110

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

E-print Network

, 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

Schultheiss, Oliver C.

111

61 FR 4621 - Xanthan Gum-Modified, Produced by the Reaction of Xanthan Gum and Glyoxal; Tolerance Exemption  

Federal Register 2010, 2011, 2012, 2013, 2014

...180 [OPP-300410; FRL-4994-4] Xanthan Gum-Modified, Produced by the Reaction of Xanthan Gum and Glyoxal; Tolerance Exemption AGENCY...SUMMARY: This document proposes that xanthan gum-modified, produced by the...

1996-02-07

112

61 FR 19854 - Xanthan Gum-Modified, Produced by the Reaction of Xanthan Gum and Glyoxal; Tolerance Exemption  

Federal Register 2010, 2011, 2012, 2013, 2014

...180 [OPP-300410A; FRL-5359-5] Xanthan Gum-Modified, Produced by the Reaction of Xanthan Gum and Glyoxal; Tolerance Exemption AGENCY...SUMMARY: This document exempts xanthan gum-modified, produced by the...

1996-05-03

113

Ask a Periodontist (Frequently Asked Questions about Gum Disease)  

MedlinePLUS

... Comprehensive Periodontal Evaluation Periodontal Treatments and Procedures Non-Surgical Periodontal Treatments Gum Graft Surgery Laser Treatment for Gum Disease Regenerative Procedures Dental Crown ...

114

Gum chewing affects academic performance in adolescents  

Technology Transfer Automated Retrieval System (TEKTRAN)

Chewing gum may have an impact on improved memory during specific tasks of recognition and sustained attention. Research objective was to determine the effect of gum chewing on standardized test scores and math class grades of eighth grade students. Four math classes, 108 students, were randomized i...

115

Mind Your Mouth: Preventing Gum Disease  

MedlinePLUS

... can simply cause swollen gums or give you bad breath. It can also ruin your smile or even make you lose your teeth. The good news is that gum disease can be prevented with daily dental care. The problem begins with bacteria. Our mouths are packed with these tiny microbes. ...

116

Problem Solving: Bubble Gum Contest  

NSDL National Science Digital Library

This professional development video clip presents students engaged in The Common Core Practice Standard #1—Make sense of problems and persevere in solving them. The learners gather data for a bubble gum contest, as part of a larger activity involving recording data and writing up results. Students understand the problem and persevere with the task as they independently go to other classrooms to conduct their survey. Additional resources include a video transcript, teaching tips, and a link to a professional development reflection activity based upon the video.

WGHB Boston

2013-01-01

117

62 FR 61619 - Carrageenan, Locust Bean Gum and Xanthan Gum Blend Used as a Binder in Certain Cured Pork Products  

Federal Register 2010, 2011, 2012, 2013, 2014

...bean gum and 15 percent xanthan gum reduces the purge of brine in water-added...blend of carrageenan, locust bean gum, and xanthan gum in ``Ham Water Added'' and...purge from the ham products during storage. This binder is not permitted...

1997-11-19

118

The effect of sugars on the retention of ethyl butyrate by gellan gels.  

PubMed

The effect of sucrose, glucose and fructose on the retention of ethyl butyrate by low acyl gellan gels was investigated by static headspace gas chromatography. The air/biopolymer partition coefficient (K) and percentage of retention (R%) were determined. When 5 g of sample were left to equilibrate at 37 °C for 24 h, the obtained results were explained in terms of gel rigidity, as increased rigidity resulted in increased aroma retention. Glucose showed the greatest aroma release among the sugars and resulted in either the same or increased aroma release with increasing concentration. Increasing concentrations of fructose and sucrose did not alter aroma release significantly. For 15 g of sample mass, sucrose exhibited the lowest partition coefficient values among the sugars. The two higher sucrose concentrations resulted in decreased coefficient values. For fructose and glucose, aroma retention decreased with increasing concentration. The percentage of retention values were positive for all sugars, throughout their concentration range and for both experiments. PMID:24679778

Evageliou, Vasiliki; Patsiakou, Anna

2014-08-15

119

Gellan sulfate core platinum coil with tenascin-C promotes intra-aneurysmal organization in rats.  

PubMed

The aims of this study were to develop a new coil, gellan sulfate core platinum coil (GSCC), that delivers tenascin-C (TNC) to an aneurysm (GSCC-TNC) and to evaluate the effects on intra-aneurysmal organization. We performed in vitro adsorption tests of TNC to gellan sulfate (GS). GSCC-TNC was produced by immersing GSCC in TNC solution under the following conditions (TNC concentration 10, 50, or 100 ?g/mL; TNC immersion time 15, 30, or 60 min) by monitoring intra-aneurysmal organization in a rat blind-ended aneurysm model. In addition, 20 rats randomly underwent implantation of a platinum coil or the GSCC-TNC produced under optimum conditions into an aneurysm, whose organization effects were compared in a blind fashion at 2 weeks post-surgery. GS demonstrated a high affinity to TNC in a dose-dependent fashion (affinity constant?=?1.79?×?10(10) (M(-1))). GSCC immersed in 10 ?g/mL of TNC solution for 30 and 60 min induced similar and better organization of aneurysmal cavity compared with that for 15 min (the ratio of the organized areas in an aneurysmal cavity-15 min, 27.2?±?11.8 %; 30 min, 75.6?±?11.9 %; 60 min, 82.6?±?19.7 %, respectively) with the preservation of the aneurysmal wall structure, while higher TNC concentrations caused the destruction of the aneurysmal wall. GSCC-TNC produced under 10 ?g/mL of TNC solution for 30 min showed a significantly better organization of aneurysms compared with bare platinum coils in rats. A newly developed coil, GSCC-TNC, may be effective for improving intra-aneurysmal organization after coil embolization. PMID:24939607

Hamada, Kazuhide; Miura, Yoichi; Toma, Naoki; Miyamoto, Keiichi; Imanaka-Yoshida, Kyoko; Matsushima, Satoshi; Yoshida, Toshimichi; Taki, Waro; Suzuki, Hidenori

2014-10-01

120

Preparation and in vitro antibacterial evaluation of gatifloxacin mucoadhesive gellan system  

PubMed Central

Background and the purpose of the study The poor bioavailability and therapeutic response exhibited by the conventional ophthalmic solutions due to precorneal elimination of the drug may be overcome by the use of mucoadhesive in situ gel forming systems that are instilled as drops into the eye and undergo a sol-gel transition in the cul-de-sac and have good mucoadhesion with ocular mucus layers. The objective of this study was to formulate ophthalmic mucoadhesive system of gatifloxacin (GTN) and to evaluate its in vitro antibacterial potential against, Staphylococcus aureus and Escherichia coli. Methods : Mucoadhesive systems were prepared using gellan combined with sodium carboxymethylcellulose (NaCMC) or sodium alginate to enhance the gel bioadhesion properties. The prepared formulations were evaluated for their gelation, and rheological behaviors, mucoadhesion force, in vitro drug release, and antibacterial activity. Results All formulations in non-physiological or physiological conditions showed pseudoplastic behaviors. Increase in the concentration of mucoadhesive agent enhanced the mucoadhesive force significantly. In vitro release of gatifloxacin from the mucoadhesive system in simulated tear fluid (STF, pH of 7.4) was influenced significantly by the properties and concentration of gellan, sodium carboxymethyl cellulose and sodium alginate. Significant reduction in the total bacterial count was observed between drug solution (control) and mucoadhesive batches against both tested organisms. Major conclusion The developed mucoadhesive system is a viable alternative to conventional eye drops of GTN due to its ability to enhance bioavailability through its longer precorneal residence time and ability to sustain the release of the drug. PMID:22615622

Kesavan, K.; Nath, G.; Pandit, JK.

2010-01-01

121

Welan gum: microbial production, characterization, and applications.  

PubMed

Microbial exopolysaccharides are of high molecular weight, environment friendly valuable natural polymers, having applications in diverse areas such as food industry, pharmaceutical industry, cement systems and cosmetics industries. Welan gum, a microbial product holds an important place among the exopolysaccharides due to its novel properties and potential applications. The biopolymer welan gum is synthesized by the fermentation process mainly by the Alcaligenes sp., and is composed of polymer of tetrasaccharide backbone chain containing l-mannose, l-rhamnose, d-glucose, and d-glucuronic acid. It acts as a thickening, suspending, binding, emulsifying, stabilizing and viscosifying agent. It has important commercial applications in the cement systems. This review is primarily focused on the microbial production, purification, recovery, and the characterization based on the available published literature on the welan gum. Besides this, the biosynthesis and the various process factors affecting the production as well as properties of welan gum and its various applications have also been addressed. PMID:24508918

Kaur, Varinder; Bera, Manav B; Panesar, Parmjit S; Kumar, Harish; Kennedy, J F

2014-04-01

122

Does Your Chewing Gum Lose Its Sweetness?  

NSDL National Science Digital Library

In the first part of the activity, each student chews a piece of gum until it loses its sweetness, and then leaves the gum to dry for several days before weighing it to determine the amount of mass lost. This mass corresponds to the amount of sugar in the gum, and can be compared to the amount stated on the package label. In the second part of the activity, students work in groups to design and conduct new experiments based on questions of their own choosing. These questions arise naturally from observations during the first experiment, and from students' own experiences with and knowledge of the many varieties of chewing and bubble gums available.

Engineering K-Ph.D. Program,

123

Locust bean gum: a versatile biopolymer.  

PubMed

Biopolymers or natural polymers are an attractive class of biodegradable polymers since they are derived from natural sources, easily available, relatively cheap and can be modified by suitable reagent. Locust bean gum is one of them that have a wide potentiality in drug formulations due to its extensive application as food additive and its recognized lack of toxicity. It can be tailored to suit its demands of applicants in both the pharmaceutical and biomedical areas. Locust bean gum has a wide application either in the field of novel drug delivery system as rate controlling excipients or in tissue engineering as scaffold formation. Through keen references of reported literature on locust bean gum, in this review, we have described critical aspects of locust bean gum, its manufacturing process, physicochemical properties and applications in various drug delivery systems. PMID:23544637

Prajapati, Vipul D; Jani, Girish K; Moradiya, Naresh G; Randeria, Narayan P; Nagar, Bhanu J

2013-05-15

124

Fractionation of Mastic Gum in Relation to Antimicrobial Activity  

PubMed Central

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.

Sharifi, Mohammad Sharif; Hazell, Stuart Loyd

2009-01-01

125

21 CFR 582.7343 - Locust bean gum.  

Code of Federal Regulations, 2013 CFR

...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...

2013-04-01

126

21 CFR 582.7343 - Locust bean gum.  

Code of Federal Regulations, 2012 CFR

...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...

2012-04-01

127

21 CFR 582.7343 - Locust bean gum.  

Code of Federal Regulations, 2011 CFR

...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...

2011-04-01

128

21 CFR 582.7343 - Locust bean gum.  

Code of Federal Regulations, 2010 CFR

...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...

2010-04-01

129

21 CFR 582.7343 - Locust bean gum.  

Code of Federal Regulations, 2014 CFR

...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...

2014-04-01

130

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

PubMed

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

Singh, Sudarshan; Bothara, Sunil B

2014-01-01

131

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

PubMed Central

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

Singh, Sudarshan; Bothara, Sunil B.

2014-01-01

132

21 CFR 172.780 - Acacia (gum arabic).  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2009-04-01 true Acacia (gum arabic). 172.780 Section...Specific Usage Additives § 172.780 Acacia (gum arabic). The food additive...following prescribed conditions: (a) Acacia (gum arabic) is the dried gummy...

2010-04-01

133

21 CFR 172.780 - Acacia (gum arabic).  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Acacia (gum arabic). 172.780 Section...Specific Usage Additives § 172.780 Acacia (gum arabic). The food additive...following prescribed conditions: (a) Acacia (gum arabic) is the dried gummy...

2014-04-01

134

21 CFR 172.780 - Acacia (gum arabic).  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Acacia (gum arabic). 172.780 Section...Specific Usage Additives § 172.780 Acacia (gum arabic). The food additive...following prescribed conditions: (a) Acacia (gum arabic) is the dried gummy...

2012-04-01

135

21 CFR 172.780 - Acacia (gum arabic).  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Acacia (gum arabic). 172.780 Section...Specific Usage Additives § 172.780 Acacia (gum arabic). The food additive...following prescribed conditions: (a) Acacia (gum arabic) is the dried gummy...

2011-04-01

136

21 CFR 172.780 - Acacia (gum arabic).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Acacia (gum arabic). 172.780 Section...Specific Usage Additives § 172.780 Acacia (gum arabic). The food additive...following prescribed conditions: (a) Acacia (gum arabic) is the dried gummy...

2013-04-01

137

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...

138

78 FR 43226 - Xanthan Gum From Austria and China  

Federal Register 2010, 2011, 2012, 2013, 2014

...Nos. 731-TA-1202-03 (Final)] Xanthan Gum From Austria and China Determinations...by reason of imports from Austria of xanthan gum provided for in subheading 3913.90...injury by reason of imports from China of xanthan gum provided for in subheading...

2013-07-19

139

The Gum Nebula and Related Problems  

NASA Technical Reports Server (NTRS)

Proceedings of a symposium concerning the Gum Nebula (GN) and related topics are reported. Papers presented include: Colin Gum and the discovery of the GN; identification of the GN as the fossil Stromgren sphere of Vela X Supernova; size and shape of GN; formation of giant H-2 regions following supernova explosions; radio astronomy Explorer 1 observations of GN; cosmic ray effects in the GN; low intensity H beta emission from the interstellar medium; and how to recognize and analyze GN. Astronomical charts and diagrams are included.

1973-01-01

140

Jaw and gum tumours in children  

Microsoft Academic Search

Introduction  Jaw and gum tumours are rare conditions in children. Children presenting with jaw tumours during 2001 till 2007 are presented.\\u000a Their modes of presentation, operative procedures and findings, histology and post operative results have been described.\\u000a \\u000a \\u000a \\u000a Materials and methods  Fourteen children presenting with jaw and gum tumours are retrospectively analysed. Acute inflammatory and developmental cyst\\u000a are excluded from the study. Relevant

Hemonta Kumar Dutta

2009-01-01

141

Design, formulation and evaluation of caffeine chewing gum  

PubMed Central

Background: Caffeine which exists in drinks such as coffee as well as in drug dosage forms in the global market is among the materials that increase alertness and decrease fatigue. Compared to other forms of caffeine, caffeine gum can create faster and more prominent effects. In this study, the main goal is to design a new formulation of caffeine gum with desirable taste and assess its physicochemical properties. Materials and Methods: Caffeine gum was prepared by softening of gum bases and then mixing with other formulation ingredients. To decrease the bitterness of caffeine, sugar, aspartame, liquid glucose, sorbitol, manitol, xylitol, and various flavors were used. Caffeine release from gum base was investigated by mechanical chewing set. Content uniformity test was also performed on the gums. The gums were evaluated in terms of organoleptic properties by the Latin-Square design at different stages. Results: After making 22 formulations of caffeine gums, F11 from 20 mg caffeine gums and F22 from 50 mg caffeine gums were chosen as the best formulation in organoleptic properties. Both types of gum released about 90% of their own drug content after 30 min. Drug content of 20 and 50 mg caffeine gum was about 18.2-21.3 mg and 45.7-53.6 mg respectively. Conclusion: In this study, 20 and 50 mg caffeine gums with suitable and desirable properties (i.e., good taste and satisfactory release) were formulated. The best flavor for caffeine gum was cinnamon. Both kinds of 20 and 50 mg gums succeeded in content uniformity test. PMID:24223387

Aslani, Abolfazl; Jalilian, Fatemeh

2013-01-01

142

Guar Gum, Xanthan Gum, and HPMC Can Define Release Mechanisms and Sustain Release of Propranolol Hydrochloride  

Microsoft Academic Search

The objectives were to characterize propranolol hydrochloride-loaded matrix tablets using guar gum, xanthan gum, and hydroxypropylmethylcellulose\\u000a (HPMC) as rate-retarding polymers. Tablets were prepared by wet granulation using these polymers alone and in combination,\\u000a and physical properties of the granules and tablets were studied. Drug release was evaluated in simulated gastric and intestinal\\u000a media. Rugged tablets with appropriate physical properties were

Muhammad Akhlaq Mughal; Zafar Iqbal; Steven Henry Neau

2011-01-01

143

21 CFR 184.1333 - Gum ghatti.  

Code of Federal Regulations, 2012 CFR

... ), to 5 ml of a cold 1-in-100 aqueous solution of the gum. An immediate, voluminous, opaque precipitate indicates acacia. A small precipitate or clear solution which produces an opaque flocculent precipitate upon the addition of 1 ml of 3 N...

2012-04-01

144

21 CFR 184.1333 - Gum ghatti.  

Code of Federal Regulations, 2014 CFR

... ), to 5 ml of a cold 1-in-100 aqueous solution of the gum. An immediate, voluminous, opaque precipitate indicates acacia. A small precipitate or clear solution which produces an opaque flocculent precipitate upon the addition of 1 ml of 3 N...

2014-04-01

145

21 CFR 184.1333 - Gum ghatti.  

Code of Federal Regulations, 2010 CFR

... ), to 5 ml of a cold 1-in-100 aqueous solution of the gum. An immediate, voluminous, opaque precipitate indicates acacia. A small precipitate or clear solution which produces an opaque flocculent precipitate upon the addition of 1 ml of 3 N...

2010-04-01

146

21 CFR 184.1333 - Gum ghatti.  

Code of Federal Regulations, 2013 CFR

... ), to 5 ml of a cold 1-in-100 aqueous solution of the gum. An immediate, voluminous, opaque precipitate indicates acacia. A small precipitate or clear solution which produces an opaque flocculent precipitate upon the addition of 1 ml of 3 N...

2013-04-01

147

21 CFR 184.1333 - Gum ghatti.  

Code of Federal Regulations, 2011 CFR

... ), to 5 ml of a cold 1-in-100 aqueous solution of the gum. An immediate, voluminous, opaque precipitate indicates acacia. A small precipitate or clear solution which produces an opaque flocculent precipitate upon the addition of 1 ml of 3 N...

2011-04-01

148

Periodontal (Gum) Disease Causes, Symptoms, and Treatments  

E-print Network

spaces (called "pockets") that become infected. The body's immune system fights the bacteria and have to be removed. | 3 #12;Risk Factors · Smoking. Need another reason to quit smoking? Smoking is one of the most significant risk factors associated with the development of gum disease. Additionally, smoking can

Bandettini, Peter A.

149

The oral health benefits of chewing gum.  

PubMed

The use of sugar-free gum provides a proven anti-caries benefit, but other oral health effects are less clearly elucidated. Chewing sugar-free chewing gum promotes a strong flow of stimulated saliva, which helps to provide a number of dental benefits: first, the higher flow rate promotes more rapid oral clearance of sugars; second, the high pH and buffering capacity of the stimulated saliva help to neutralise plaque pH after a sugar challenge; and, lastly, studies have shown enhanced remineralisation of early caries-like lesions and ultimately prospective clinical trials have shown reduced caries incidence in children chewing sugar-free gum. This paper reviews the scientific evidence for these functional claims and discusses other benefits, including plaque and extrinsic stain reduction, along with the possibility of adding specific active agents, including fluoride, antimicrobials, urea and calcium phosphates, to enhance these inherent effects. The evidence for a specific effect of xylitol as a caries-therapeutic agent is also discussed. In conclusion, it is asserted that chewing gum has a place as an additional mode of dental disease prevention to be used in conjunction with the more traditional preventive methods. PMID:23573702

Dodds, Michael W J

2012-01-01

150

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

PubMed

ABSTRACT 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

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

2014-08-21

151

An association between temporomandibular disorder and gum chewing.  

PubMed

This single center, randomized, small study sought to investigate the prevalence and frequency of chewing gum consumption, and whether there is a relationship between these factors and the presence of symptoms associated with temporomandibular disorder (TMD). Subjects were divided into 7 groups based on their parafunctional oral habits. Of these, subjects who chewed gum were divided into 5 subgroups (A-E) based on their gum chewing habits. Group A chewed gum <1 hour/day (n = 12), Group B chewed gum 1-2 hours/day (n = 11), Group C chewed gum 3 hours/day (n = 6), and Group D chewed gum >3 hours at a time (n = 8); the frequency of gum chewing in Groups A-D was once a week. Group E subjects chewed gum 1-3 times/week for at least 1 hour each occurrence (n = 2). Sixty-three percent of the subjects in Group D reported TMD symptoms of arthralgia and myofascial pain. Thirty-three percent of the subjects in Group C showed symptoms of arthralgia. Eighty-three percent of the subjects in Group A and 27% in Group B reported myofascial pain. All subjects in Group E reported masseter hypertrophy. The remaining 2 groups were Group F, subjects that didn't chew gum but had other parafunctional oral habits (n = 2), and Group G, subjects who didn't have parafunctional oral habits (n = 12). PMID:25369399

Correia, Diana; Real Dias, Maria Carlos; Castanho Moacho, Antonio; Crispim, Pedro; Luis, Henrique; Oliveira, Miguel; Carames, Joao

2014-01-01

152

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

PubMed

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

Kora, Aruna Jyothi; Sashidhar, Rao Beedu

2015-02-01

153

Direct photography of the Gum Nebula  

NASA Technical Reports Server (NTRS)

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.

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

1976-01-01

154

The Gum nebula and related problems  

NASA Technical Reports Server (NTRS)

Papers were presented in conference sessions on the Gum nebula, the Vela X remnant, the hot stars gamma Velorum and zeta Puppis, the B associations in the Vela-Puppis complex, and pulsars. Ground-based optical and radio astronomy; rocket and satellite observations in the radio, visible, ultraviolet, and X-ray regions; and theoretical problems in the physical state of the interstellar medium, stellar evolution, and runaway star dynamics were considered.

Maran, S. P.; Brandt, J. C.; Stecher, T. P.

1971-01-01

155

Validating the applicability of the GUM procedure  

NASA Astrophysics Data System (ADS)

This paper is directed at practitioners seeking a degree of assurance in the quality of the results of an uncertainty evaluation when using the procedure in the Guide to the Expression of Uncertainty in Measurement (GUM) (JCGM 100?:?2008). Such assurance is required in adhering to general standards such as International Standard ISO/IEC 17025 or other sector-specific standards. We investigate the extent to which such assurance can be given. For many practical cases, a measurement result incorporating an evaluated uncertainty that is correct to one significant decimal digit would be acceptable. Any quantification of the numerical precision of an uncertainty statement is naturally relative to the adequacy of the measurement model and the knowledge used of the quantities in that model. For general univariate and multivariate measurement models, we emphasize the use of a Monte Carlo method, as recommended in GUM Supplements 1 and 2. One use of this method is as a benchmark in terms of which measurement results provided by the GUM can be assessed in any particular instance. We mainly consider measurement models that are linear in the input quantities, or have been linearized and the linearization process is deemed to be adequate. When the probability distributions for those quantities are independent, we indicate the use of other approaches such as convolution methods based on the fast Fourier transform and, particularly, Chebyshev polynomials as benchmarks.

Cox, Maurice G.; Harris, Peter M.

2014-08-01

156

40 CFR 454.20 - Applicability; description of the manufacture of gum rosin and turpentine subcategory.  

Code of Federal Regulations, 2012 CFR

... Applicability; description of the manufacture of gum rosin and turpentine subcategory... Applicability; description of the manufacture of gum rosin and turpentine subcategory...applicable to discharges resulting from the manufacture of gum rosin and...

2012-07-01

157

40 CFR 454.20 - Applicability; description of the manufacture of gum rosin and turpentine subcategory.  

Code of Federal Regulations, 2013 CFR

... Applicability; description of the manufacture of gum rosin and turpentine subcategory... Applicability; description of the manufacture of gum rosin and turpentine subcategory...applicable to discharges resulting from the manufacture of gum rosin and...

2013-07-01

158

40 CFR 454.20 - Applicability; description of the manufacture of gum rosin and turpentine subcategory.  

Code of Federal Regulations, 2011 CFR

... Applicability; description of the manufacture of gum rosin and turpentine subcategory... Applicability; description of the manufacture of gum rosin and turpentine subcategory...applicable to discharges resulting from the manufacture of gum rosin and...

2011-07-01

159

40 CFR 454.20 - Applicability; description of the manufacture of gum rosin and turpentine subcategory.  

Code of Federal Regulations, 2010 CFR

... Applicability; description of the manufacture of gum rosin and turpentine subcategory... Applicability; description of the manufacture of gum rosin and turpentine subcategory...applicable to discharges resulting from the manufacture of gum rosin and...

2010-07-01

160

40 CFR 454.20 - Applicability; description of the manufacture of gum rosin and turpentine subcategory.  

Code of Federal Regulations, 2014 CFR

... Applicability; description of the manufacture of gum rosin and turpentine subcategory... Applicability; description of the manufacture of gum rosin and turpentine subcategory...applicable to discharges resulting from the manufacture of gum rosin and...

2014-07-01

161

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

Federal Register 2010, 2011, 2012, 2013, 2014

...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...

2012-10-26

162

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

PubMed

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

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

2014-03-01

163

Quantification and Qualification of Bacteria Trapped in Chewed Gum  

PubMed Central

Chewing of gum contributes to the maintenance of oral health. Many oral diseases, including caries and periodontal disease, are caused by bacteria. However, it is unknown whether chewing of gum can remove bacteria from the oral cavity. Here, we hypothesize that chewing of gum can trap bacteria and remove them from the oral cavity. To test this hypothesis, we developed two methods to quantify numbers of bacteria trapped in chewed gum. In the first method, known numbers of bacteria were finger-chewed into gum and chewed gums were molded to standard dimensions, sonicated and plated to determine numbers of colony-forming-units incorporated, yielding calibration curves of colony-forming-units retrieved versus finger-chewed in. In a second method, calibration curves were created by finger-chewing known numbers of bacteria into gum and subsequently dissolving the gum in a mixture of chloroform and tris-ethylenediaminetetraacetic-acid (TE)-buffer. The TE-buffer was analyzed using quantitative Polymerase-Chain-Reaction (qPCR), yielding calibration curves of total numbers of bacteria versus finger-chewed in. Next, five volunteers were requested to chew gum up to 10 min after which numbers of colony-forming-units and total numbers of bacteria trapped in chewed gum were determined using the above methods. The qPCR method, involving both dead and live bacteria yielded higher numbers of retrieved bacteria than plating, involving only viable bacteria. Numbers of trapped bacteria were maximal during initial chewing after which a slow decrease over time up to 10 min was observed. Around 108 bacteria were detected per gum piece depending on the method and gum considered. The number of species trapped in chewed gum increased with chewing time. Trapped bacteria were clearly visualized in chewed gum using scanning-electron-microscopy. Summarizing, using novel methods to quantify and qualify oral bacteria trapped in chewed gum, the hypothesis is confirmed that chewing of gum can trap and remove bacteria from the oral cavity. PMID:25602256

Wessel, Stefan W.; van der Mei, Henny C.; Morando, David; Slomp, Anje M.; van de Belt-Gritter, Betsy; Maitra, Amarnath; Busscher, Henk J.

2015-01-01

164

Quantification and qualification of bacteria trapped in chewed gum.  

PubMed

Chewing of gum contributes to the maintenance of oral health. Many oral diseases, including caries and periodontal disease, are caused by bacteria. However, it is unknown whether chewing of gum can remove bacteria from the oral cavity. Here, we hypothesize that chewing of gum can trap bacteria and remove them from the oral cavity. To test this hypothesis, we developed two methods to quantify numbers of bacteria trapped in chewed gum. In the first method, known numbers of bacteria were finger-chewed into gum and chewed gums were molded to standard dimensions, sonicated and plated to determine numbers of colony-forming-units incorporated, yielding calibration curves of colony-forming-units retrieved versus finger-chewed in. In a second method, calibration curves were created by finger-chewing known numbers of bacteria into gum and subsequently dissolving the gum in a mixture of chloroform and tris-ethylenediaminetetraacetic-acid (TE)-buffer. The TE-buffer was analyzed using quantitative Polymerase-Chain-Reaction (qPCR), yielding calibration curves of total numbers of bacteria versus finger-chewed in. Next, five volunteers were requested to chew gum up to 10 min after which numbers of colony-forming-units and total numbers of bacteria trapped in chewed gum were determined using the above methods. The qPCR method, involving both dead and live bacteria yielded higher numbers of retrieved bacteria than plating, involving only viable bacteria. Numbers of trapped bacteria were maximal during initial chewing after which a slow decrease over time up to 10 min was observed. Around 10(8) bacteria were detected per gum piece depending on the method and gum considered. The number of species trapped in chewed gum increased with chewing time. Trapped bacteria were clearly visualized in chewed gum using scanning-electron-microscopy. Summarizing, using novel methods to quantify and qualify oral bacteria trapped in chewed gum, the hypothesis is confirmed that chewing of gum can trap and remove bacteria from the oral cavity. PMID:25602256

Wessel, Stefan W; van der Mei, Henny C; Morando, David; Slomp, Anje M; van de Belt-Gritter, Betsy; Maitra, Amarnath; Busscher, Henk J

2015-01-01

165

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

E-print Network

Effects of sugarless chewing gum as a stimulant on progesterone, cortisol, and testosterone Testosterone Cortisol Progesterone Chewing gum Saliva collection Sugarless chewing gum is a frequently used conditions (gum, no gum) as well as in a saliva pool and water, either untreated or treated with chewing gum

Schultheiss, Oliver C.

166

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

PubMed

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

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

2014-08-01

167

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

PubMed

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

Ogunjimi, Abayomi Tolulope; Alebiowu, Gbenga

2014-04-01

168

Effect of polyol gums on dental plaque in orthodontic patients  

Microsoft Academic Search

Sixty 11- to 15-year-old children wearing fixed orthodontic appliances were given chewing gums containing polyol for daily use after meals and snacks, to study whether the chewing of gums that contained slowly fermentable polyols (xylitol and sorbitol) affects the amount of dental plaque and the number of mutans streptococci present in plaque and saliva. The 60 subjects were randomly divided

K. P. Isotupa; S. Gunn; C.-Y. Chen; D. Lopatin; K. K. Mäkinen

1995-01-01

169

Gum Arabic as a Cause of Occupational Allergy  

PubMed Central

Background. Gum arabic is a potential sensitizer in food industry. Methods. We examined 11 candy factory workers referred to examinations due to respiratory and skin symptoms paying attention to exposure and sensitization to gum arabic. Skin tests, pulmonary function tests, and respiratory provocation tests were carried out as indicated by the symptoms and findings. Results. Occupational asthma, caused by gum arabic was diagnosed in 4/11 candy factory workers and two of them had also occupational contact urticaria and one had occupational rhinitis. One of them had oral symptoms associated with ingestion of products containing gum arabic. Conclusions. Airborne exposure to gum arabic may cause sensitization leading to allergic rhinitis, asthma, and urticaria. PMID:21747872

Viinanen, Arja; Salokannel, Maija; Lammintausta, Kaija

2011-01-01

170

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

PubMed

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

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

2015-03-01

171

The rheological properties of tara gum (Caesalpinia spinosa).  

PubMed

The rheological properties of tara gum, as affected by concentration, temperature, pH and the presence of salts and sucrose, were investigated by using steady and dynamic shear measurements and atomic force microscope observation. Tara gum exhibited non-Newtonian, pseudoplastic behaviour without thixotropy at tested concentrations (0.2-1.0%, w/v). Salts (CaCl2 and NaCl) led to a viscosity reduction, which was more sensitive to Ca(2+) than to Na(+). The gum had stable viscosity over a wide pH range (pH 3-11), and the influence of sucrose was concentration dependent. Increasing temperature from 20°C to 80°C decreased the gum viscosity. Frequency sweeps indicated that tara gum (1.0% w/v) behaved as a liquid at low frequency, and acted more like a gel at high frequency. With the decrease of concentration, tara gum may show a viscous property rather than an elastic one. These results are potentially useful for the application of tara gum in food processing. PMID:25172722

Wu, Yanbei; Ding, Wei; Jia, Lirong; He, Qiang

2015-02-01

172

Randomised controlled trial of nicotine chewing-gum.  

PubMed Central

The effectiveness of 2 mg nicotine chewing-gum as an aid to stopping smoking was compared with a placebo containing 1 mg nicotine, but unbuffered, in a double-blind randomised trial. Of 58 subjects given the active gum, 27 (47%) were not smoking at one-year follow-up compared with 12 (21%) of the 58 subjects treated with placebo (p less than 0.025). By the most stringent criterion of outcome, 18 (31%) subjects in the active treatment group and eight (14%) in the placebo group had not smoked at all from the start of treatment to follow-up at one year (p less than 0.05). Subjects receiving the active gum experienced less severe withdrawal symptoms and rated their gum as more helpful than did the placebo group. Minor side effects were common but only gastric symptoms were more frequent with the active gum. Subjects receiving active gum used it for longer than those receiving placebo but most stopped using it within six months and only four (7%) developed longer-term dependence. The number of gums used daily correlated significantly with pretreatment blood nicotine concentrations in the active treatment group and with pretreatment cigarette consumption in the placebo group. A lower pretreatment blood nicotine value was the best predictor of success at one year (p less than 0.001) but there was no significant relation to cigarette consumption, sex, and social class. The results clearly confirm the usefulness of nicotine chewing-gum as an aid to stopping smoking and imply a definite role for nicotine in cigarette dependence and withdrawal. Successful use of the gum requires careful attention to subjects' expectations and clear instructions on how to use it. PMID:6809161

Jarvis, M J; Raw, M; Russell, M A; Feyerabend, C

1982-01-01

173

Material and tableting properties of Azadirachta indica gum with reference to official acacia gum.  

PubMed

This study determined the material and tableting properties of Azadirachta indica gum (NMG) relative to acacia gum (ACA). The morphological properties were assessed with size and shape factors of aspect ratio, roundness, irregularity and equivalent-circle-diameter. The tableting properties of the gums were determined using compressional characteristics, tensile strength (TS), brittle fracture index (BFI) and crushing-strength-friability/disintegration-time ratio (CSFR/DT). The results suggest that NMG possesses larger, irregular and more elongated particles than ACA. The onset and amount of plastic deformation occurring in NMG was faster and higher, respectively, than in ACA. The result shows that, although ACA tablets were stronger, their tendency to cap/laminate was higher than in NMG tablets. The NMG tablets possess lower DT than those of ACA, while the CSFR/DT result suggests that a better balance exists between the strength and weakness of NMG tablets. The study concluded that NMG can be a useful excipient in tablet formulation. PMID:24779199

Ogunjimi, Abayomi T; Alebiowu, Gbenga

2014-01-01

174

Evaluation of mucoadhesive potential of gum cordia, an anionic polysaccharide.  

PubMed

The study involves mucoadhesive evaluation by formulating buccal discs using fluconazole as the model drug. The effect of compression pressure and gum cordia/lactose ratio on the ex vivo bioadhesion time and in vitro release of fluconazole was optimized using central composite experimental design. It was observed that the response ex vivo bioadhesion time was affected significantly by the proportion of gum cordia in the buccal discs while the in vitro release of fluconazole from the buccal discs was influenced significantly by the compression pressure. The optimized batch of buccal discs comprised of gum cordia/lactose - 0.66, fluconazole - 20 mg and was compressed at the pressure of 6600 kg. Further, it provided the ex vivo bioadhesion of 22 h and in vitro release of 80% in 24h. In conclusion, gum cordia is a promising bucoadhesive polymer. PMID:23280130

Ahuja, Munish; Kumar, Suresh; Kumar, Ashok

2013-04-01

175

Chitosan/cashew gum nanogels for essential oil encapsulation.  

PubMed

Nanogels based on chitosan and cashew gum were prepared and loaded with Lippia sidoides oil. Several parameters such as cashew gum concentration and relative oil content in the matrix had their influence on nanogel properties investigated. Nanogels were characterized regarding their morphologies, particle size distributions, zeta potential, Fourier transform infrared spectroscopy and essential oil contents. The release profile was investigated by UV/vis spectroscopy and its efficacy was determined through bioassays. Results showed that samples designed using relative ratios matrix:oil 10:2, gum:chitosan 1:1 and 5% gum concentration showed high loading (11.8%) and encapsulation efficiency (70%). Nanogels were found to exhibit average sizes in the range 335-558 nm. In vitro release profiles showed that nanoparticles presented slower and sustained release. Bioassays showed that larval mortality was related mainly to oil loading, with samples presenting more effective larvicide efficacies than the pure L. sidoides oil. PMID:24750942

Abreu, Flávia O M S; Oliveira, Erick F; Paula, Haroldo C B; de Paula, Regina C M

2012-08-01

176

Evaluation of CDs and chewing gum in teaching dental anatomy.  

PubMed

The purposes of this pilot study were: 1. to compare two methods of teaching dental anatomy-CD + lab vs. standard lecture + lab; and 2. to determine whether actively chewing gum during lecture, lab and studying would have an effect on learning. Only the written examination average scores for the gum vs. no gum chewing groups showed differences that appear to be educationally meaningful, though not statistically significant because of the limited number of subjects in this pilot study. This pilot study suggests that: 1. the cost-effective method of using a self-study CD is as educationally effective as a standard lecture; 2. gum chewing resulted in higher scores in the written examination; and 3. future, full-sized studies should be conducted to confirm these findings. PMID:16925010

Allen, Kenneth L; Galvis, Diana; Katz, Ralph V

2006-01-01

177

Xylitol gum and maternal transmission of mutans streptococci.  

PubMed

An important caries prevention strategy for children includes measures to interfere with transmission of mutans streptococci (MS). This study confirmed the effectiveness of maternal early exposure to xylitol chewing gum on mother-child transmission of MS. After screening, 107 pregnant women with high salivary MS were randomized into two groups: xylitol gum (Xylitol; n = 56) and no gum (Control; n = 51) groups. Maternal chewing started at the sixth month of pregnancy and terminated 13 months later in the Xylitol group. Outcome measures were the presence of MS in saliva or plaque of the children until age 24 months. The Xylitol-group children were significantly less likely to show MS colonization than Control-group children aged 9-24 months. The Control-group children acquired MS 8.8 months earlier than those in the Xylitol group, suggesting that maternal xylitol gum chewing in Japan shows beneficial effects similar to those demonstrated in Nordic countries. PMID:19948944

Nakai, Y; Shinga-Ishihara, C; Kaji, M; Moriya, K; Murakami-Yamanaka, K; Takimura, M

2010-01-01

178

Isolation and rheological characterization of Mucuna flagellipes seed gum  

Microsoft Academic Search

The gum from Mucuna flagellipes seed endosperm has been isolated and characterised using capillary viscometry and steady shear and small deformation oscillatory rheometry. The endosperm was found to constitute 67.15% of the whole seed and yielded 32.6% of gum. The Huggins and Kraemer plots obtained by capillary viscometry gave an intrinsic viscosity of 7.9dL\\/g and viscosity average molecular mass was

Louis M. Nwokocha; Peter A. Williams

2009-01-01

179

Design, formulation and evaluation of green tea chewing gum  

PubMed Central

Background: The main purpose of this study is to design, formulate and evaluate the green tea gums with a suitable taste and quality in order to produce an anti-oxidant chewing gum. Materials and Methods: Fresh green tea leaves obtained from Northern Iran for extraction. Maceration is the extraction method that is used in this study. The contents of caffeine, catechin and flavonoids of the hydro alcoholic extract were measured. Various formulations of the 120 mg green tea extract chewing gums with different sweeteners, flavoring agents and various gum bases were prepared afterward release pattern, content uniformity, organoleptic results and other properties were characterized. Results: The contents of caffeine, catechin and flavonoid of the hydro alcoholic extraction were 207.32 mg/g, 130.00 mg/g and 200.82 mg/g, respectively. Release pattern of green tea chewing gum with different gum base ratios and various sweeteners in phosphate buffer were prepared. A total of 60 persons who were 20-30 years of age, participated in our panel test for organoleptic properties such as taste, stiffness, stickiness, etc., Acceptable gum was the one with the same ratio of the used rubber bases. Cinnamon selected as the preferred taste by volunteers. Combination of aspartame, sugar and maltitol has appropriate taste. The effect of various sweetener on release pattern was negligible, on the other hand rubber bases ratio variation, changed the release pattern obviously. Conclusion: The green tea chewing gum with sugar, maltitol and aspartame sweeteners and cinnamon flavor, using the same rubber bases ratio may be a desirable antioxidant product. PMID:25161989

Aslani, Abolfazl; Ghannadi, Alireza; Khalafi, Zeinab

2014-01-01

180

Bioadhesive delivery of metformin using prosopis gum with antidiabetic potential.  

PubMed

The antidiabetic properties of prosopis gum alone and as a bioadhesive base for the delivery of metformin are presented. The bioadhesive value of the gum was commensurate with those of Carbopol 974-P and sodium carboxymethyl cellulose (NaCMC). The release of the drug was higher from prosopis gum based bioadhesive formulations than from NaCMC and Carbopol 974-P products. This was shown by the shorter time required to reach t(50) (the time required for 50% of the drug to be released) or t(20) (time required for 20% of the drug to be released) for the release of metformin. The gum showed moderate antidiabetic properties when used alone. In combination with metformin in a bioadhesive form, the glucose lowering effect was found to be synergistic. The areas under the plasma drug concentration vs. time curves (AUCs) for the bioadhesive combinations were similar to those of the drugs alone in an aqueous system. This shows that the gum did not interfere with absorption of the incorporated drug. However, the areas under the effect vs. time curves (AUECs) were much higher when combined in a bioadhesive form than with the drug alone. The AUCs obtained with NaCMC based bioadhesive formulations were relatively smaller than those of metformin in an aqueous system and the combinations of metformin and prosopis gum. PMID:12736508

Adikwu, Michael Umale; Yoshikawa, Yukako; Takada, Kanji

2003-05-01

181

Effect of Arabic gum, xanthan gum and orange oil on flavor release from diluted orange beverage emulsion  

Microsoft Academic Search

The influence of main emulsion components namely Arabic gum (13–20% w\\/w), xanthan gum (0.3–0.20% w\\/w) and orange oil (10–14% w\\/w) on semi-quantitative headspace analysis of target volatile flavor compounds released from a model orange beverage (diluted orange beverage emulsion) was evaluated by using a three-factor circumscribed central composite design (CCCD). For optimization procedure, the peak area of 13 volatile flavor

Hamed Mirhosseini; Chin Ping Tan; Nazimah S. A. Hamid; Salmah Yusof

2008-01-01

182

Gellan co-polysaccharide micellar solution of budesonide for allergic anti-rhinitis: an in vitro appraisal.  

PubMed

The aim of this study was to design a novel amphiphilic co-polysaccharide for the development of anti-rhinitis micellar solution of budesonide. Herein, a long alkyl chain (C18) was successfully grafted onto gellan polysaccharide by etherification reaction. The dispersion of co-polysaccharide in water led to formation of spherical, nanomicellar structures. Depending upon the co-polysaccharide:drug weight ratio (1:1, 1:2 and 1:3), a maximum drug loading (>95%) was noted at the lowest level. The nanomicelles were in the range of 371-750nm and showed negative zeta potential (-48.3 to -67.2mV) values indicating their stability in aqueous system. They exhibited a longer dissolution profile in simulated nasal fluid (pH 5.5). The dissolution efficiency (39.79±0.93%) was maximal at the lowest polymer: drug ratio in 6h. The drug release was found to follow first order kinetic model. Korsmeyer-peppas modeling of in vitro drug release data indicated that besides simple diffusion, no other physical phenomenon was involved in the event of drug release from the nanostructures. Differential scanning calorimetry analysis suggested some degree of physical incompatibility; however Infrared spectroscopy revealed chemical compatibility between drug and co-polysaccharide. Thus, the co-polysaccharide micellar system offers a splendid outlook in controlled intranasal delivery of budesonide for the symptomatic relief of anti-rhinitis. PMID:24820153

Maiti, Sabyasachi; Chakravorty, Amrita; Chowdhury, Moumita

2014-07-01

183

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....

184

Studies on gum of Moringa oleifera for its emulsifying properties  

PubMed Central

Background: Emulsion has been a form of presenting water insoluble substances for a long period of time. Now a day, it has been a way of presenting various intravenous additives and diagnostic agents in X-ray examinations. Various substances can be used as emulsifying agent, which can be operationally defined as a stabilizer of the droplets formed of the internal phase. Materials and Methods: Gum from Moringa oleifera was evaluated for its emulsifying properties. Castor oil emulsions 30 percent (o/w), containing 2 to 4% Moringa oleifera gum was prepared. Emulsions containing equivalent concentration of acacia were also prepared for comparison. All the emulsions prepared were stored at room temperature and studied for stability at various time intervals for 8 weeks. The prepared emulsions were evaluated for creaming rate, globule size and rate of coalescence. 23 factorial design was chosen to investigate the effects of centrifugation, pH, temperature changes and electrolytes on the creaming rate and globule size. Results: The results of the investigations show that the gum of Moringa oleifera possesses better emulsifying properties as compared to gum acacia. Conclusion: Gum of Moringa oleifera could be used in pharmaceutical and non-pharmaceutical preparation. PMID:24741276

Panda, Dibya Sundar

2014-01-01

185

Delivery of active agents from chewing gum for improved remineralization.  

PubMed

Most surrogate measures of caries were developed to test products containing fluoride, typically at relatively high and closely controlled oral concentrations. However, since the primary mechanism for the remineralization of early enamel caries lesions by chewing gum is through stimulation of saliva, delivering Ca and Pi to the demineralized enamel lesion, established methods may lack the sensitivity to detect the additional benefit of an active agent without the strong remineralizing potential of fluoride. Issues related to the release of active agents from the gum matrix, dilution in the saliva, and limited oral retention time, along with taste, safety, regulatory, and cost concerns, impose further limitations. This paper reviews the efficacy of some active agents used in chewing gum for improved remineralization and includes results from in situ testing of calcium-containing gums, including calcium lactate, tetracalcium phosphate/dicalcium phosphate anhydrous, calcium citrate/encapsulated phosphate, and a calcium lactate/sodium phosphate blend. Despite promising in vitro data from these agents, they did not provide consistently superior results from in situ testing. There is a need to develop better predictive in vitro models for chewing gum, as well as improved sensitivity of in situ models to discriminate relatively small amounts of remineralization against a background of high biological variability. PMID:22899681

Dodds, M W J; Chidichimo, D; Haas, M S

2012-09-01

186

Oat gum lowers glucose and insulin after an oral glucose load.  

PubMed

Foods containing soluble dietary fibers delay glucose absorption and lower postprandial plasma glucose. This effect of oat bran has been attributed to oat gum (80% beta-glucan). However, purified oat gum has previously not been available for human studies. In this study the glucose and insulin responses to consuming 14.5 g of specifically prepared oat gum with 50 g glucose were compared with the response to guar gum with glucose and to glucose alone in nine healthy, fasting subjects. Plasma glucose and insulin increases after the glucose drink were greater than after both gum meals between 20 and 60 min (P less than 0.01). The responses to the two gum meals were nearly identical. These results establish that the more palatable oat gum lowers postprandial plasma glucose and insulin concentrations in humans and may be comparable with or of greater benefit than guar gum. PMID:1852092

Braaten, J T; Wood, P J; Scott, F W; Riedel, K D; Poste, L M; Collins, M W

1991-06-01

187

Effect of chewing gums containing xylitol or probiotic bacteria on salivary mutans streptococci and lactobacilli  

Microsoft Academic Search

The aim was to evaluate the effect of xylitol and probiotic chewing gums on salivary mutans streptococci (MS) and lactobacilli\\u000a (LB). The material consisted of 80 healthy young adults (21–24 years) who volunteered after informed consent. They were assigned\\u000a by random into one of four parallel study groups: A, probiotic gum group; B, xylitol gum group; C, probiotic + xylitol gum

E. Çaglar; S. C. Kavaloglu; O. O. Kuscu; N. Sandalli; P. L. Holgerson; S. Twetman

2007-01-01

188

Effects of xanthan, guar, carrageenan and locust bean gum addition on physical, chemical and sensory properties of meatballs.  

PubMed

This study evaluated the effects of xanthan gum, guar gum, carrageenan and locust bean gum on physical, chemical and sensory properties of meatballs. Meatball samples were produced with three different formulations including of 0.5, 1, and 1.5% each gum addition and gum added samples were compared with the control meatballs. Physical and chemical analyses were carried out on raw and cooked samples separately. Moisture contents of raw samples decreased by addition of gums. There were significant decreases (p?gum when compared with control. Ash contents and texture values increased with gum addition to meatballs. Meatball redness decreased with more gum addition in raw and cooked meatball samples, which means that addition of gums resulted in a lighter-coloured product. According to sensory analysis results, locust bean gum added (1%) samples were much preferred by the panelists. PMID:24803701

Demirci, Zeynep Ozben; Y?lmaz, Ismail; Demirci, Ahmet ?ukru

2014-05-01

189

Successful difficult intubation. Use of the gum elastic bougie.  

PubMed

The reliability of two signs of tracheal placement of a gum elastic bougie was studied. These signs were clicks (produced as the tip of the bougie runs over the tracheal cartilages) and hold up of the bougie as it is advanced (when the tip reaches the small bronchi). Ninety-eight simulated and two genuine Grade 3 difficult intubations were attempted with the aid of a gum elastic bougie. Seventy-eight tracheal and 22 oesophageal placements of the bougie resulted. No clicks or hold up occurred with the bougie in the oesophagus. Clicks were recorded in 89.7% of tracheal placements of the bougie. Hold up at between 24-40 cm occurred in all tracheal placements. We conclude that these signs are reliable and that they should be taught as part of any difficult intubation drill in which the gum elastic bougie is used. PMID:3407866

Kidd, J F; Dyson, A; Latto, I P

1988-06-01

190

Factors affecting the emulsifying and rheological properties of gum acacia in beverage emulsions  

Microsoft Academic Search

Gum acacia, a natural hydrocolloid, is extensively used as an emulsifier\\/stabilizer in beverage emulsions. Factors that may affect emulsion formation, emulsion stability and viscosity of the emulsion concentrate were studied to assess their significance, including proximal composition of the gum (protein content and mineral content), gum processing prior to emulsion preparation (pasteurization and demineralization), and pH of the dilute emulsion.

R. A Buffo; G. A Reineccius; G. W Oehlert

2001-01-01

191

Laser-induced-fluorescence detection of gums in jet fuels. Final report, Jul 90May 92  

Microsoft Academic Search

The current method (ASTM D381) of determining the concentration of gums in jet fuels is a lengthy procedure requiring a large sample size. Because gum formation is believed to be an important step in the formation of deposits in fuel systems used in jet aircraft, a non-intrusive method of performing spatially resolved measurements of gum concentration in high temperature flow

D. W. Naegeli; R. H. Hill

1992-01-01

192

TECHNICAL NOTE: The effect of the green additive guar gum on the properties of magnetorheological fluid  

NASA Astrophysics Data System (ADS)

Magnetorheological (MR) fluid containing guar gum was prepared for the first time by ball-milling the guar gum powder together with silicone oil and carbonyl iron powder. By forming a coating layer over the ground carbonyl iron powder, the guar gum improves the sedimentation stability and thixotropy of the MR fluid effectively.

Fang, Chen; Zhao, Bin Yuan; Chen, LeSheng; Wu, Qing; Liu, Nan; Hu, Ke Ao

2005-02-01

193

Prospective of guar gum and its derivatives as controlled drug delivery systems  

Microsoft Academic Search

Guar gum is a non-ionic polysaccharide that is found abundantly in nature and has many properties desirable for drug delivery applications. However, due to its high swelling characteristics in aqueous solution, the use of guar gum as delivery carriers is limited. Guar gum can be modified by derivatization, grafting and network formation to improve its property profile for a wide

M. Prabaharan

2011-01-01

194

Effects of Chewing Different Flavored Gums on Salivary Flow Rate and pH  

PubMed Central

Chewing gum increases salivary flow rate (SFR) and pH, but differences in preferences of gum flavor may influence SFR and pH. The aim of this paper was to assess the effect of five different flavors of sucrose-free chewing gum on the salivary flow rate and pH in healthy dental students in Isfahan, Iran. Fifteen (7 men and 8 women) healthy dental student volunteers collected unstimulated saliva and then chewed one of five flavored gums for 6?min. The whole saliva was collected and assessed for 6 consecutive days. After unstimulated saliva was collected, stimulated saliva was collected at interval of 0-1, 1–3, and 3–6 minutes after the start of different flavored chewing gums. The SFR and salivary pH were measured. The SFR increased in all five flavored gums at 1, 3, and 6 minutes after start of chewing gums (P < 0.001). The flow rate of all products reached peak in the 1st minute of stimulation, except spearmint-flavored gums which reached peak in the 6th minute. In the 1st minute, the strawberry-flavored gums showed the highest SFR. During 1–3 minutes, strawberry- and apple-flavored gums showed higher SFR, respectively. Only the spearmint- and cinnamon-flavored gum significantly increased salivary pH. Gum flavored can affect the SFR and pH and special flavors can be advised for different individuals according to their oral conditions. PMID:22505903

Karami Nogourani, Maryam; Janghorbani, Mohsen; Kowsari Isfahan, Raha; Hosseini Beheshti, Mozhgan

2012-01-01

195

TECHNICAL NOTE: The effect of the green additive guar gum on the properties of magnetorheological fluid  

Microsoft Academic Search

Magnetorheological (MR) fluid containing guar gum was prepared for the first time by ball-milling the guar gum powder together with silicone oil and carbonyl iron powder. By forming a coating layer over the ground carbonyl iron powder, the guar gum improves the sedimentation stability and thixotropy of the MR fluid effectively.

Chen Fang; Bin Yuan Zhao; LeSheng Chen; Qing Wu; Nan Liu; Ke Ao Hu

2005-01-01

196

Effect of chewing gums containing xylitol or probiotic bacteria on salivary mutans streptococci and lactobacilli.  

PubMed

The aim was to evaluate the effect of xylitol and probiotic chewing gums on salivary mutans streptococci (MS) and lactobacilli (LB). The material consisted of 80 healthy young adults (21-24 years) who volunteered after informed consent. They were assigned by random into one of four parallel study groups: A, probiotic gum group; B, xylitol gum group; C, probiotic + xylitol gum group; and D, placebo gum group. The gums were taken three times daily after meals, and the intervention period was 3 weeks. The probiotic gums contained two strains of Lactobacilli reuteri (ATCC 55730 at a dose of 1 x 10(8) CFU/gum and ATCC PTA 5289 at a dose of 1 x 10(8) CFU/gum), and each pellet of the xylitol gum contained approximately 1.0 g xylitol as single sweetener. Pretreatment and posttreatment samples of stimulated whole saliva were collected and quantified for MS and LB with chair-side kits. A statistically significant reduction (p < 0.05) of salivary MS was displayed in group A and B after the intervention when compared with baseline. A similar but nonsignificant tendency was seen in group C. No alterations of salivary LB was demonstrated in any group. In conclusion, daily chewing on gums containing probiotic bacteria or xylitol reduced the levels of salivary MS in a significant way. However, a combination of probiotic and xylitol gums did not seem to enhance this effect. PMID:17574481

Caglar, E; Kavaloglu, S C; Kuscu, O O; Sandalli, N; Holgerson, P L; Twetman, S

2007-12-01

197

Preparation and characterization of carboxymethyl guar gum nanoparticles.  

PubMed

Carboxymethyl guar gum nanoparticles (CMGGNPs) were synthesized by nanoprecipitation and sonication method. This method was used for the first time for the synthesis of carboxymethyl guar gum nanoparticles. It was found that the formation of nanoparticles might depend upon the sonication time, solvent, and stirring time. Nanoparticles were characterized by SEM, TEM, XRD and FTIR. The sizes of the particles in suspension have been found in the range 12-30nm. It was concluded that such type of nanoparticles may be used in pharmaceutical and drug delivery. PMID:24832982

Gupta, Anek Pal; Verma, Devendra Kumar

2014-07-01

198

[Does chewing gum accelerate recovery after abdominal surgery?].  

PubMed

Postoperative ileus is a common condition that delays recovery after an abdominal surgery. The early use of sham feeding, with chewing gum, stimulates peristalsis; thus should allow an earlier nutrition. Searching in Epistemonikos database, which is maintained by screening 20 databases, we identified 14 systematic reviews including 24 randomized trials. We combined the evidence using meta-analysis and generated a summary of findings following the GRADE approach. We concluded that chewing gum probably reduces the length of hospital stay after an abdominal surgery. PMID:25627680

Rada, Gabriel; Viñuela, José

2014-01-01

199

A "SOLUBLE SPECIFIC SUBSTANCE" DERIVED FROM GUM ARABIC  

PubMed Central

1. By partial acid hydrolysis a specific carbohydrate may be isolated from gum arabic (gum acacia). This carbohydrate is comparable in its precipitating activity for Type II (and Type III) antipneumococcus serum with the bacterial soluble specific substances themselves. 2. On hydrolysis this fraction yields galactose and two or more complex sugar acids, one of which appears to be a disaccharide add comparable with those isolated from the specific polysaccharides of the Type III pneumococcus and the Type A Friedländer bacillus. 3. The significance of these findings is discussed. PMID:19869586

Heidelberger, Michael; Avery, Oswald T.; Goebel, Walther F.

1929-01-01

200

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

PubMed

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

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

2015-04-15

201

Postmenopausal Women May Be at Risk of Gum Disease  

MedlinePLUS

... at increased risk for gum disease, a new study suggests. The research included almost 200 women, aged 51 to 80. They had all gone through menopause within the last 10 years, didn't smoke and hadn't taken hormone replacement therapy, bone loss prevention drugs or diabetes medications for ...

202

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...

203

Cigarette and Nicotine Chewing Gum Toxicity in Children  

Microsoft Academic Search

A prospective review of 51 cases of tobacco ingestion and 5 cases of nicotine resin chewing gum exposure was conducted to evaluate the incidence and degree of toxicity caused by these products in children. A dose-response relationship was observed for cigarette exposures. Nine of 10 children ingesting more than one cigarette or three cigarette butts developed signs or symptoms, while

S. C. Smolinske; D. G. Spoerke; S. K. Spiller; K. M. Wruk; K. Kulig; B. H. Rumackt

1988-01-01

204

UTILIZATION OF OKRA GUM FOR TREATMENT OF TANNERY EFFLUENT  

Microsoft Academic Search

Several natural polymeric flocculants are used for water purification. Natural polymers, mainly polysaccharides, by virtue of being biodegradable, non-toxic, shear stable and easily available, are becoming popular in domestic and industrial effluent treatment. Okra gum obtained from seedpods of Hibiscus esculentus is an anionic polysaccharide. It is used as flocculant for removal of solid wastes from tannery effluent in this

M. Agarwal; S. Rajani; A. Mishra; J. S. P. Rai

2003-01-01

205

Chewing gum increases energy expenditure before and after controlled breakfasts.  

PubMed

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

Kresge, Daniel L; Melanson, Kathleen

2015-04-01

206

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 ...

207

Toxicologic evaluation of modified gum acacia: mutagenicity, acute and subchronic toxicity.  

PubMed

Modified gum acacia, produced from acacia gum by a process analogous to the production of modified food starch, was tested for mutagenicity in the microbial reverse mutation assay. The assay employed a wide range of dose levels, both with and without metabolic activation. Test results gave no indication that modified gum acacia possessed any mutagenic potential. The acute oral toxicity of modified gum acacia was determined in two studies employing Sprague-Dawley rats, and the LD50 values were found to be >2000 mg/kg. The primary dermal irritation potential of modified gum acacia was evaluated in rabbits by the Draize method. Test results indicated that modified gum acacia was slightly irritating by the Environmental Protection Agency (EPA) classification but not a primary irritant by Consumer Product Safety Commission (CPSC) guidelines. The subchronic toxicity of modified gum acacia was examined in Sprague-Dawley rats fed diets containing 0%, 1%, 2.5%, and 5% modified gum acacia for 13 weeks. No dose-related effects on survival, growth, hematology, blood chemistry, organ weights, or pathologic lesions were observed. Results of these studies indicate that modified gum acacia does not possess mutagenic potential and that animals are not adversely affected by acute or subchronic exposure to modified gum acacia. PMID:18078702

Schmitt, D; Tran, N; Riefler, S; Jacoby, J; Merkel, D; Marone, P; Naouli, N

2008-03-01

208

Dietary guar gum effects on postprandial blood glucose, insulin and hydroxyproline in humans.  

PubMed

Meals (425 kcal) containing various doses of guar gum (0, 2.5, 7.5 or 12.5 g) were ingested by nine healthy male subjects after a 12-h fast. The rise in blood glucose was higher after the control meal without guar gum than after the guar gum-containing meals, which all gave a similar rise in glucose. In contrast, increased doses of guar gum led to a greater reduction in the postprandial rise in insulin. The postprandial increase in serum hydroxyproline, an amino acid added to all meals, was decreased in a similar manner by all of the guar gum doses. Gastric emptying was measured after the control meal without guar gum and the meal containing 12.5 g of guar gum by monitoring 51Cr, which was added to the meals. Guar gum was found to reduce the variation between individuals, as well as the initial rate of gastric emptying, which correlated with changes in both serum hydroxyproline (rs = 0.93, P less than 0.01) and blood glucose (rs = 0.83, P less than 0.01). The effectiveness of guar gum in reducing postprandial response was lost after heating and homogenization for canning. A threshold in the reduction in rise of glucose or hydroxyproline was reached with the lowest dose (2.5 g) of viscous guar gum; larger doses had no additional effects. The reduced absorption seems to be an effect of a slower gastric emptying rate. PMID:2559957

Torsdottir, I; Alpsten, M; Andersson, H; Einarsson, S

1989-12-01

209

Disruption of Xylella fastidiosa CVC gumB and gumF genes affects biofilm formation without a detectable influence on exopolysaccharide production.  

PubMed

Xylella fastidiosa causes citrus variegated chlorosis (CVC), a destructive disease of citrus. Xylella fastidiosa forms a biofilm inside plants and insect vectors. Biofilms are complex structures involving X. fastidiosa cells and an extracellular matrix which blocks water and nutrient transport in diseased plants. It is hypothesized that the matrix might be composed of an extracellular polysaccharide (EPS), coded by a cluster of nine genes closely related to the xanthan gum operon of Xanthomonas campestris pv. campestris. To understand the role of X. fastidiosa gum genes on biofilm formation and EPS biosynthesis, we produced gumB and gumF mutants. Xylella fastidiosa mutants were obtained by insertional duplication mutagenesis and recovered after triply cloning the cells. Xylella fastidiosa gumB and gumF mutants exhibited normal cell characteristics; typical colony morphology and EPS biosynthesis were not altered. It was of note that X. fastidiosa mutants showed a reduced capacity to form biofilm when BCYE was used as the sustaining medium, a difference not observed with PW medium. Unlike X. campestris pv. campestris, the expression of the X. fastidiosa gumB or gumF genes was not regulated by glucose. PMID:16553859

Souza, Leonardo C A; Wulff, Nelson A; Gaurivaud, Patrice; Mariano, Anelise G; Virgílio, Andréa C D; Azevedo, João L; Monteiro, Patrícia B

2006-04-01

210

Locust bean gum: Exploring its potential for biopharmaceutical applications  

PubMed Central

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

Dionísio, Marita; Grenha, Ana

2012-01-01

211

A Comparative Study of the Innervation of the Gum  

PubMed Central

In this paper we give a comparative study of the innervation of the connective tissues of the gum underlying the epithelium. Our material was taken from carnivores, rodents, insectivores and men. The fibres form superficial and deep plexuses and leashes, and specialized nerve-endings are also present. The types of specialized nerve-endings seen have been:— (1) Coils which are situated either in the intra-papillary zone of the deeper connective tissue. (2) Ruffini-like nerve-endings and convoluted fibres the presence of which in the gum has not been previously described. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7p1059-aFig. 8Fig. 9Fig. 10Fig. 11Fig. 12 PMID:19992024

Stewart, D.; Lewinsky, W.

1939-01-01

212

Strategy to identify and quantify polysaccharide gums in gelled food concentrates.  

PubMed

A strategy for the unambiguous identification and selective quantification of xanthan gum and locust bean gum (LBG) in gelled food concentrates is presented. DNA detection by polymerase chain reaction (PCR) showed to be a fast, sensitive, and selective method that can be used as a first screening tool in intact gelled food concentrates. An efficient isolation procedure is described removing components that may interfere with subsequent analyses. NMR spectroscopy enabled the direct identification of xanthan gum and the discrimination between different galactomannans in the isolated polysaccharide fraction. An enzymatic fingerprinting method using endo-?-mannanase, in addition to being used to differentiate between galactomannans, was developed into a selective, quantitative method for LBG, whereas monosaccharide analysis was used to quantify xanthan gum. Recoveries for xanthan gum and LBG were 87% and 70%, respectively, with in-between day relative standard deviations below 20% for xanthan gum and below 10% for LBG. PMID:25053026

Grün, Christian H; Sanders, Peter; van der Burg, Monique; Schuurbiers, Eric; van Adrichem, Linda; van Velzen, Ewoud J J; de Roo, Niels; Brunt, Kommer; Westphal, Yvonne; Schols, Henk A

2015-01-01

213

An assessment of gum-based environmental enrichment for captive gummivorous primates.  

PubMed

In the wild, many primates consume gums exuded from trees, and many species are gum specialists. In spite of this, few data exist concerning gum feeding in captivity. Using a web-based survey of 46 zoos in 12 countries, we evaluated the extent to which zoos feed gum to primates. We found that although callitrichids and galagos receive gum-based enrichment, cercopithecines generally do not. Environmental enrichment is important for stimulating naturalistic behavior to promote the psychological wellbeing of animals. Thus, gum-based enrichment is important for captive gummivores. Our study highlights the need to improve environmental enrichment for captive gummivores, in particular that of cercopithecines. This is most striking for the patas monkey (Erythrocebus patas), an obligate gummivore. The exchange of ecological data between field research and captive settings is crucial, and is just one way primate caretakers can contribute to the conservation and welfare of some of our closest living relatives. PMID:21319210

Huber, Hillary F; Lewis, Kerrie P

2011-01-01

214

Expression, purification and crystallization of the outer membrane lipoprotein GumB from Xanthomonas campestris  

PubMed Central

GumB is a predicted outer membrane lipoprotein that is involved in the synthesis and/or secretion of xanthan gum. This exopolysaccharide, produced by Xanthomonas campestris, is valuable in industry because of its important rheological properties. Solution of the GumB structure will provide insight into the polymerization and/or secretion mechanisms of xanthan gum. GumB was overexpressed and purified and diffraction-quality crystals of native GumB were obtained. A complete data set was collected to 2.54?Å resolution with an R p.i.m. of 0.034. The crystals belonged to space group P212121, with unit-cell parameters a = 84.4, b = 90.5, c = 120.7?Å. PMID:23027761

Jacobs, Melisa; Salinas, Silvina R.; Bianco, María I.; Ielpi, Luis

2012-01-01

215

Structure and rheological properties of acacia gum dispersions  

Microsoft Academic Search

The structure of acacia gum molecules was determined using size exclusion chromatography coupled to multi-angle laser light scattering, refractometry and viscosimetry. Results revealed the presence of many molecular species, including large aggregates, the arabino-galactan protein fraction (AraGP), the arabino-galactan fraction (AraG) and the glyco-protein fraction (GP). The Mw of the two major fractions AraGP and AraG were 2.3 106 and

Christian Sanchez; Denis Renard; Paul Robert; Christophe Schmitt; Jacques Lefebvre

2002-01-01

216

Effect of salt on turbulent drag reduction of xanthan gum.  

PubMed

The turbulent flow of an aqueous KCl solution driven by a rotating disc in a closed chamber showed significant drag reduction (DR) when a small amount of xanthan gum (XG) was added. The effects of the experimental parameters (XG and KCl concentrations, and time) on the drag reduction efficiency were examined. While the DR efficiency of XG decreased with increasing salt (KCl) concentration, the time-dependent DR efficiency was found to be fitted well using Brostow model equation. PMID:25659708

Hong, Cheng Hai; Choi, Hyoung Jin; Zhang, Ke; Renou, Frederic; Grisel, Michel

2015-05-01

217

Effect of molecular configuration of Xanthan gum drage reduction  

Microsoft Academic Search

Drag reduction in turbulent pipe flow has been studied using dilute xanthan gum solutions. The primary goal of the studies was torelate the molecular configuration of xanthan in solutions of varying ionic strength to its effectiveness as a drag reducer. Xanthan solutions of various concentrations (10-250 wppm) in glycerine\\/water (12.5\\/87.5) and with 0.5%NaCl, added were studied over a wide Reynolds

Skip Rochefort; Stanley Middleman

1986-01-01

218

Synthesis and characterization of monodisperse copper nanoparticles using gum acacia  

NASA Astrophysics Data System (ADS)

A simple method was put forward in this paper for preparing colloidal copper nanoparticles in aqueous solutions using copper sulfate, gum acacia and hydrazine hydrate as copper precursor, capping agents and reducing agents, respectively, without any inert gas. The formation of nanosized copper was confirmed by its characteristic surface plasmon absorption peak at 604 nm in UV-vis spectra. The transmission electron microscopic (TEM) and scanning electron microscope (SEM) images show that the as-synthesized copper fine spherical particles are distributed uniformly with a narrow distribution from 3 nm to 9 nm. The X-ray diffraction (XRD) and high resolution transmission electron microscopic (HRTEM) demonstrated that the obtained metallic nanoparticles are single crystalline copper nanoparticles. Fourier transform infra-red (FT-IR) spectroscopic data suggested that the copper nanoparticles are coated with gum acacia. The effects of the quantity of gum acacia on the particle size were investigated by the UV-vis spectra and TEM images. The growth process of the nanoparticles was monitored by the UV-vis spectra. The mechanism of the formation copper nanoparticles was discussed. The process raised in this study can be served as an excellent candidate for the preparation of copper nanoparticles in a large scale production.

Dong, Chunfa; Cai, Hao; Zhang, Xianglin; Cao, Chuanliang

2014-03-01

219

Insulin chewing gum: Need of the day for diabetic patients  

PubMed Central

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

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

2011-01-01

220

Xanthan gum stabilized gold nanoparticles: characterization, biocompatibility, stability and cytotoxicity.  

PubMed

Xanthan gum (XG) has been widely used in food, pharmaceutical and cosmetic industries. In the present study, we explored the potential of XG in the synthesis of gold nanoparticle. XG was used as both reducing and stabilizing agent. The effect of various formulation and process variables such as temperature, reaction time, gum concentration, gum volume and gold concentration, in GNP preparation was determined. The XG stabilized, rubey-red XGNP were obtained with 5 ml of XG aqueous solution (1.5 mg/ml). The optimum temperature was 80°C whereas the reaction time was 3 h. The optimized nanoparticles were also investigated as drug delivery carrier for doxorubicin hydrochloride. DOX loaded gold nanoparticles (DXGP) were characterized by dynamic light scattering, TEM, FTIR, and DSC analysis. The synthesized nanoparticle showed mean particle size of 15-20 nm and zeta potential -29.1 mV. The colloidal stability of DXGP was studied under different conditions of pH, electrolytes and serum. Nanoparticles were found to be stable at pH range between pH 5-9 and NaCl concentration up to 0.5 M. In serum, nanoparticles showed significant stability up to 24h. During toxicity studies, nanoparticles were found biocompatible and non-toxic. Compared with free DOX, DXGP displayed 3 times more cytotoxicity in A549 cells. In conclusion, this study provided an insight to synthesize GNP without using harsh chemicals. PMID:24906721

Pooja, Deep; Panyaram, Sravani; Kulhari, Hitesh; Rachamalla, Shyam S; Sistla, Ramakrishna

2014-09-22

221

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

Microsoft Academic Search

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

I T Johnson; J M Gee

1981-01-01

222

Gum chewing reduces the time to first defaecation after pelvic surgery: A randomised controlled study.  

PubMed

Post-operative ileus is a major complication that increases the morbidity in patients who had abdominal surgery. Several different procedures have been used to manage bowel function, including adequate pain control, prokinetic drugs and supportive strategies. The present study aimed to assess the effect of chewing gum on bowel recovery in patients undergoing gynaecologic abdominal surgeries. A total of 137 patients were randomised into gum-chewing and control groups. Patients in the gum-chewing group began chewing gum at post-operative 3rd h and chewed gum thereafter every 4 h daily, for 30 min each time. All patients received the same post-operative treatment. Primary outcome measures were the time to first passage of flatus and time to first passage of stool. The secondary outcome measures included the first hearing of normal bowel sounds, nausea and the time until discharge from the hospital. Compared with the control group, the time interval between operation and first flatus was shorter in the gum-chewing group (median, 33 h vs 30 h). However, the difference was not significant (p = 0.381). The first defaecation time was significantly shorter in the gum-chewing group. The median time to first defaecation was 67 (20-105) h in the control group and 45 (12-97) h in the gum-chewing group (p < 0.01). Gum chewing is safe, well tolerated and it allows early defaecation after gynaecologic abdominal surgery. PMID:25325342

Tazegül Pekin, A; Kerimo?lu, O Seçilmi?; Do?an, N U; Y?lmaz, S A; Kebapc?lar, A G; Genço?lu Bakbak, B B; Celik, C

2014-10-17

223

A study of the fate of gum karaya in the rat.  

PubMed

Rats were fed a diet containing 5% gum karaya for 24 h and faeces and urine were collected over 72 h. Faeces were examined, after methanolysis, by gas chromatography--mass spectometry and the quantity and monosaccharide composition of the faecal polysaccharide were compared with the dose and original composition of the gum polysaccharide. Gum-derived rhamnose was not found in the urine. Indications of minor quantitative changes in composition but no evidence of extensive degradation or absorption of gum polysaccharide, were found. PMID:7147269

Brown, P M; Pringuer, M A; Anderson, M W

1982-10-01

224

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

PubMed

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

Barak, Sheweta; Mudgil, Deepak

2014-05-01

225

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

PubMed

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

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

2013-05-15

226

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

PubMed

Sugarless chewing gum is a frequently used stimulant to collect saliva samples for hormone analyses. This study tested the effect of sugarless chewing gum on cortisol, testosterone, and progesterone concentrations measured in saliva samples collected from 8 individuals at different times of the day (morning, evening) and under different collection conditions (gum, no gum) as well as in a saliva pool and water, either untreated or treated with chewing gum. Sugarless chewing gum raised all progesterone concentrations by 20 to 40pg/mL, corresponding to a twofold increase, relative to no-gum controls and attenuated salivary testosterone and cortisol concentrations. It is recommended that the use of sugarless chewing gum as a stimulant should be avoided with saliva samples. PMID:23220228

Schultheiss, Oliver C

2013-01-01

227

Characterisation of natural polysaccharides (plant gums) used as binding media for artistic and historic works by capillary zone electrophoresis.  

PubMed

The monosaccharide constituents of plant gums were separated by capillary electrophoresis at pH 12.1 and detected with indirect UV absorbance. The plant gums investigated were gum arabic, gum acacia, gum tragacanth, cherry gum and locust bean gum (carob gum). The monosaccharides obtained after hydrolysis with 2M trifluoroacetic acid and lyophilisation of the hydrolysate were arabinose, galactose, mannose, rhamnose, xylose, fucose, and glucose, and the two sugar acids galacturonic and glucuronic acid, in accordance with the literature. They were separated in a background electrolyte consisting of NaOH to adjust the pH, 20 mM 2,6-pyridinedicarboxylic acid as chromophore for detection and 0.5 mM cetyltrimethylammonium bromide as additive to reverse the electroosmotic flow. Based on their electropherograms, the plant gums could be identified by their typical composition (depicted in a decision scheme) as follows: a peak of glucuronic acid, together with that of rhamnose, is indicative for gum arabic. Peaks of galacturonic acid and fucose point to gum tragacanth. Locust bean gum shows a major peak for mannose (with the concomitant galactose peak in ratio 4-1), whereas a glucuronic acid and a mannose peak together with a prominent arabinose peak indicates cherry gum. The method was applied to identify the plant gums in samples like watercolours and in several paint layers like gum tempera or those with egg white or drying oils as additives. Artificial aging experiments of thin layers of gum arabic on paper or glass carried out with UV-A radiation (366 nm) did not result in changes of the saccharide patterns, in contrast to the simultaneously conducted aging of a drying oil layer. PMID:15988990

Grössl, Michael; Harrison, Sabine; Kaml, Isabella; Kenndler, Ernst

2005-06-01

228

Stability of cumin oleoresin microencapsulated in different combination of gum arabic, maltodextrin and modified starch  

Microsoft Academic Search

Microencapsulations of cumin oleoresin by spray drying using gum arabic, maltodextrin, and modified starch (HiCap® 100) and their ternary blends as wall materials were studied for its encapsulation efficiency and stability under storage. The microcapsules were evaluated for the content and stability of volatiles, and total cuminaldehyde, ?-terpinene and p-cymene content for six weeks. Gum arabic offered greater protection than

Dattanand Kanakdande; Rajesh Bhosale; Rekha S. Singhal

2007-01-01

229

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...

230

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...

231

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

ERIC Educational Resources Information Center

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…

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

2008-01-01

232

Gum arabic glycoprotein contains glycomodules of both extensin and arabinogalactan-glycoproteins  

E-print Network

Gum arabic glycoprotein contains glycomodules of both extensin and arabinogalactan-glycoproteins Abstract Gum arabic glycoprotein (GAGP) is a large molecular weight, hydroxyproline-rich arabinogalactan contiguous Hyp blocks ¯anking two central Hyp-polysaccharides. We predict this rigidi®es the glycoprotein

Kieliszewski, Marcia

233

Laser-induced-fluorescence detection of gums in jet fuels. Final report, Jul 90-May 92  

SciTech Connect

The current method (ASTM D381) of determining the concentration of gums in jet fuels is a lengthy procedure requiring a large sample size. Because gum formation is believed to be an important step in the formation of deposits in fuel systems used in jet aircraft, a non-intrusive method of performing spatially resolved measurements of gum concentration in high temperature flow systems is a desired research tool. The present study was conducted to determine the feasibility of using laser-induced fluorescence (LIF) to monitor gum concentration in jet fuel. The study revealed several effects, such as aging and the interference of other fluoroshores with gum fluorescence, which require further investigation before LIF is to be considered a quantitative technique for measuring gums in jet fuels. However, this study showed that the formation of gums in jet fuels is detectable by LIF. The results show that gum formation in some fuels correlates strongly with LIF while for other fuels the results are ambiguous.

Naegeli, D.W.; Hill, R.H.

1992-05-01

234

Gum katira – a cheap gelling agent for plant tissue culture media  

Microsoft Academic Search

Gum katira, an insoluble gum derived from the bark of Cochlospermum religiosum, has been successfully used as a gelling agent in tissue culture media for in vitro shoot formation and rooting in Syzygium cuminii and somatic embryogenesis in Albizzia lebbeck. The epicotyl segments, excised from in vitro grown seedlings of S. cuminii, developed shoots when cultured on MS medium (Murashige

Neeru Jain; Shashi B. Babbar

2002-01-01

235

STRUCTURE/FUNCTION RELATIONSHIPS BETWEEN CORN FIBER GUMS AND THEIR EMULSIFYING PROPERTIES  

Technology Transfer Automated Retrieval System (TEKTRAN)

The U.S. food industry needs a domestically produced gum with a dependable supply and consistent quality, which can be used for preparing oil-in-water emulsions, such as citrus oil emulsions for beverages. Corn Fiber Gum (CFG) is an arabinoxylan (hemicellulose) extracted from the kernel pericarp an...

236

CORN FIBER: A POTENTIAL GUM ARABIC REPLACER FOR BEVERAGE FLAVOR EMULSIFICATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

The U.S. food industry needs a domestically produced food gum with a dependable supply and consistent quality, which can be used for preparing oil-in-water emulsions, such as citrus oil emulsions for beverages. Corn Fiber Gum (CFG) is an arabinoxylan (hemicellulose) extracted from the corn kernel p...

237

In vitro studies on guar gum based formulation for the colon targeted delivery of Sennosides  

Microsoft Academic Search

PURPOSE: The objective of the present study is to develop colon targeted drug delivery sys- tems for sennosides using guar gum as a carrier. METHODS: Matrix tablets containing various pro- portions of guar gum were prepared by wet granula- tion technique using starch paste as a binder. The tablets were evaluated for content uniformity and in vitro drug release study

Munira Momin; K. Pundarikakshudu

238

Terminological aspects of the Guide to the Expression of Uncertainty in Measurement (GUM)  

NASA Astrophysics Data System (ADS)

The Guide to the Expression of Uncertainty in Measurement (GUM) provided for the first time an international consensus on how to approach the widespread difficulties associated with conveying information about how reliable the value resulting from a measurement is thought to be. This paper examines the evolution in thinking and its impact on the terminology that accompanied the development of the GUM. Particular emphasis is put on the very clear distinction in the GUM between measurement uncertainty and measurement error, and on the reasons that even though ‘true value’ and ‘error’ are considered in the GUM to be ‘unknowable’ and, sometimes by implication, of little (or even no) use in measurement analysis, they remain as key concepts, especially when considering the objective of measurement. While probability theory in measurement analysis from a frequentist perspective was in widespread use prior to the publication of the GUM, a key underpinning principle of the GUM was to instead consider probability as a ‘degree of belief.’ The terminological changes necessary to make this transition are also covered. Even twenty years after the publication of the GUM, the scientific and metrology literatures sometimes contain uncertainty analyses, or discussions of measurement uncertainty, that are not terminologically consistent with the GUM, leading to the inability of readers to fully understand what has been done and what is intended in the associated measurements. This paper concludes with a discussion of the importance of using proper methodology and terminology for reporting measurement results.

Ehrlich, Charles

2014-08-01

239

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...

240

Effects of carboxymethylcellulose and guar gum on ice crystal propagation in a sucrose-lactose solution  

Microsoft Academic Search

The effects of carboxymethylcellulose (CMC) and guar gum on ice crystal formation have been studied using a sucrose\\/lactose solution simulating the colloid-free phase of an ice cream mix. Freezing profiles, obtained over short time intervals, showed that the addition of guar gum markedly retarded ice crystal propagation in the sugar solution, whereas addition of CMC showed no effect. The influence

S. T. Wang; S. A. Barringer; P. M. T. Hansen

1998-01-01

241

Gum cordia as carrier of antioxidants: effects on lipid oxidation of peanuts.  

PubMed

Performance of antioxidants is improved by incorporating them into polymer matrix such as polysaccharides based edible coatings. Gum cordia, an anionic polysaccharide extracted from the fruits of Cordia.myxa could be used as carrier of antioxidants by virtue of its strong adhering and emulsifying properties. This study aimed to explore the potential of gum cordia as carrier of antioxidants when applied as edible coating on peanuts. Gum Cordia was compared with carboxymethyl cellulose (CMC) in delivering of antioxidants: butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and ascorbic acid (AA). Coated and uncoated peanuts were stored at 35 °C for 126 days and coating carrier effectiveness was measured by following lipid oxidation using chemical parameters (peroxide value and thiobarbituric acid reactive species) and sensory evaluation (oxidized flavor). Significant differences (p?Gum cordia was found better than CMC to deliver the antioxidants. Gum cordia based coating in combination with BHA/BHT exhibited highest protection (290 % higher shelf life than control) based on peroxide value (40 meq.O2 kg(-1)) followed by gum codia plus BHT (244 %), gum cordia plus BHA (232 %), CMC plus BHA/BHT (184 %), CMC plus BHA (139 %), CMC plus BHT (119 %), gum cordia plus AA (96 %) and CMC plus AA (46 %). PMID:25829621

Haq, Muhammad Abdul; Azam, Mahmood; Hasnain, Abid

2015-04-01

242

77 FR 34997 - Xanthan Gum From Austria and China; Institution of Antidumping Duty Investigations and Scheduling...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Investigation Nos. 731-TA-1202-1203 (Preliminary)] Xanthan Gum From Austria and China; Institution of Antidumping...by reason of imports from Austria and/or China of xanthan gum, provided for in subheading 3913.90.20 of the...

2012-06-12

243

Interaction of calcium sulfate with xanthan gum: effect on in vitro bioadhesion and drug release behavior from xanthan gum based buccal discs of buspirone.  

PubMed

Bioadhesive polymers in buccal drug delivery systems play an important role in delivery of therapeutic drug molecules for local and systemic action. Xanthan gum, a GRAS listed natural polymer was used to design buccal discs of buspirone hydrochloride by direct compression method. Effect of calcium sulfate on bioadhesive and drug release behavior of xanthan gum buccal discs was studied. Varying amount of calcium sulfate (0%, 5%, 10%, 20%, 30%, 40% and 50%, w/w) in combination with xanthan gum was used to prepare buccal bioadhesive discs. Increase in calcium sulfate concentration resulted in faster drug release and decreased the bioadhesive strength of the designed discs. Further, in rheological evaluation it was observed that viscosity of xanthan gum gel reduces with increasing concentration of calcium sulfate. Compatibility of drug with various excipients was assessed using DSC and FTIR techniques. PMID:23907052

Jaipal, A; Pandey, M M; Abhishek, A; Vinay, S; Charde, S Y

2013-11-01

244

Evaluation of alternatives to guar gum as tackifiers for hydromulch and as clumping agents for biodegradable cat litter  

Technology Transfer Automated Retrieval System (TEKTRAN)

Guar gum is currently the principal gum used as a tackifier for hydromulch used in erosion control, and as a clumping agent in biodegradable cat litters. Due to recent severe price increases for guar gum, cheaper alternatives are being investigated. We examined several alternatives, including xanth...

245

79 FR 78797 - Xanthan Gum From the People's Republic of China: Preliminary Results of 2013 Antidumping Duty New...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Trade Administration [A-570-985] Xanthan Gum From the People's Republic of China...of the antidumping duty order on xanthan gum from the People's Republic of China...Order The scope of the order covers dry xanthan gum, whether or not coated or blended...

2014-12-31

246

79 FR 11083 - Xanthan Gum From the People's Republic of China: Initiation of Antidumping Duty New Shipper Review  

Federal Register 2010, 2011, 2012, 2013, 2014

...Trade Administration [A-570-985] Xanthan Gum From the People's Republic of China...review of the antidumping duty order on xanthan gum from the People's Republic of China...published the antidumping duty order on xanthan gum from the PRC on July 19,...

2014-02-27

247

Nicotine gum chewing: a novel strategy to shorten duration of postoperative ileus via vagus nerve activation.  

PubMed

Postoperative ileus (POI) is a transit cessation of bowel motility after surgery. Substantial evidences suggest that gum chewing accelerate the recovery of bowel motility after surgery. Perioperative nicotine administration reduces postoperative opioid use and prevents postoperative nausea and vomiting. Nicotine gum chewing combines stimulation of the cephalic-vagal reflex by gum chewing, and activation of the cholinergic anti-inflammatory pathway by nicotine administration. We therefore hypothesized that nicotine gum chewing reduces POI and improves patient outcomes such as shortening the length of hospitalization as well as saving medical costs. As nicotine gum is commercially available, inexpensive, and has been in use for many years without any severe side effects, it may have a wide clinical application in POI prevention. PMID:24998667

Wu, Z; Boersema, G S A; Jeekel, J; Lange, J F

2014-09-01

248

Albizia procera gum as an excipient for oral controlled release matrix tablet.  

PubMed

The purpose of this research was to develop and evaluate controlled release matrix tablets of paracetamol based on natural gum exudates of Albizia procera. Procera gum was characterized of its properties like compressibility index, angle of repose, viscosity and moisture content. The interaction between the gum and paracetamol was also studied through differential scanning calorimetry (DSC) and FTIR spectroscopy. Matrix tablets were then prepared by wet granulation method with different concentrations of procera gum and hydroxypropyl methylcellulose (HPMC) and evaluated for their physical properties like weight variation, hardness, friability and content uniformity. Dissolution study was conducted to characterize release mechanism from the matrix system and data were fitted to various kinetic models. The mechanism of drug release from both types of matrix tablets was found to be anomalous type. Results from various evaluations suggested that A. procera gum could be used as drug release retardant in controlled release matrix systems. PMID:24751043

Pachuau, Lalduhsanga; Mazumder, Bhaskar

2012-09-01

249

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

PubMed

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

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

2014-01-30

250

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

PubMed

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

Gastone, Francesca; Tosco, Tiziana; Sethi, Rajandrea

2014-10-01

251

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

NASA Astrophysics Data System (ADS)

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 4 g/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.

Gastone, Francesca; Tosco, Tiziana; Sethi, Rajandrea

2014-10-01

252

Optimizing microencapsulation of nisin with sodium alginate and guar gum.  

PubMed

Nisin is a widely used bacteriocin active against gram positive bacteria and is also reported to be active against some gram negative bacteria. Incorporation of nisin into food systems is another challenge as directly added nisin is prone to inactivation by food constituents. Encapsulation of nisin has been done so far in liposomes which is rather an expensive technology involving multiple processes. Other cost effective alternatives with good encapsulation efficiency and better control release properties are sought. Alginate is useful as a matrix for entrapment of bioactive compounds. Present study was aimed at optimizing conditions for microencapsulation of nisin using calcium alginate as primary wall material and guar gum as filler at different air pressures using response surface methodology. The optimum conditions were: sodium alginate concentration (2 %?w/v), guar gum concentration (0.4 %?w/v), and air pressure (0.5 bar gauge). The encapsulation efficiency of nisin in microcapsules produced under optimal conditions was 36.65 %. PMID:25477680

Narsaiah, Kairam; Jha, Shyam N; Wilson, Robin A; Mandge, Harshad M; Manikantan, Musuvadi R

2014-12-01

253

Noncatalytic hydrolysis of guar gum under hydrothermal conditions.  

PubMed

Guar gum, a naturally occurring heteropolysaccharide made of mannose and galactose, was hydrolytically degraded without a catalyst in a batch reactor to produce water-soluble (WS) saccharides including mono- and oligosaccharides. The degradation was carried out under hydrothermal conditions over ranges of temperature from 180 to 240 degrees C and of reaction time from 3 to 60min. Guar gum was readily dissolved and hydrolyzed, and the major products identified in the WS components were oligosaccharides with degrees of polymerization up to about 20, monosaccharides containing mannose and galactose, and 5-hydroxymethyl-2-furaldehyde (5-HMF). At 200 degrees C, the oligosaccharide yield, obtained from the difference between the yields of the total WS saccharides and monosaccharides, showed the highest value of 94.4% at 7min among all conditions studied, on the basis of the saccharide content in the initial sample. The oligosaccharide yield decreased with reaction time, and the yield of monosaccharides correspondingly increased, and reached the highest value of 34.5% (mannose 22.8%, galactose 11.7%) at 60min. The monosaccharides produced were further decomposed to secondary products such as 5-HMF. The maximum yield of 5-HMF obtained was 26.3% at 220 degrees C and 30min. The production and the decomposition of galactose somewhat preceded those of mannose. PMID:16529730

Miyazawa, Tetsuya; Funazukuri, Toshitaka

2006-05-22

254

New structural features of Acacia tortuosa gum exudate.  

PubMed

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

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

2015-09-01

255

Guar gum based biodegradable, antibacterial and electrically conductive hydrogels.  

PubMed

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] (molL(-1))=0.306×10(-1); [AA] (molL(-1))=0.291×10(-3) and [hexamine] (molL(-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

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

2015-04-01

256

Antioxidant Activity of Pistacia vera Fruits, Leaves and Gum Extracts  

PubMed Central

The side effects of synthetic antioxidants have been considered in different studies. Accordingly, there is an increasing interest toward the use of natural substances instead of the synthetic ones. In this study, the aqueous and ethanolic extracts of Pistacia vera leaves and fruits as well as hydroalcoholic extract of gum were tested for a possible antioxidant activity using in vitro methods. Deoxyribose assay, erythrocyte membrane lipid peroxidation and liver misrosomal non- enzymatic lipid peroxidation tests were used as an in-vitro model for determination antioxidant activity. The extract were evaluated at different concentratios: 25,100, 250, 500 and 1000 ?g/mL. In all procedures, all extracts showed free radical scavenging activity. The effect of ethanolic extract of P. vera fruit at 1000 ?g/mL was quite similar to positive control (DMSO 20 mM) in deoxyribose method. In two other tests, the ethanolic extracts of fruits and leaves were more effective than the aqueous extracts to inhibit malondialdehyde generation. Phytochemical tests showed the presence of flavonoids and tannins in Pistocia vera extracts. The present study showed that extracts of different part of P. vera have antioxidant activity in different in vitro methods. The ethanolic extracts of leaves and fruits showed more roles for antioxidant properties and gum hydroalcoholic extract demonstrated less antioxidant effect. PMID:24250515

Hosseinzadeh, Hossein; Sajadi Tabassi, Sayyed Abolghasem; Milani Moghadam, Negar; Rashedinia, Marzieh; Mehri, Soghra

2012-01-01

257

Bayesian uncertainty analysis for a regression model versus application of GUM Supplement 1 to the least-squares estimate  

NASA Astrophysics Data System (ADS)

Application of least-squares as, for instance, in curve fitting is an important tool of data analysis in metrology. It is tempting to employ the supplement 1 to the GUM (GUM-S1) to evaluate the uncertainty associated with the resulting parameter estimates, although doing so is beyond the specified scope of GUM-S1. We compare the result of such a procedure with a Bayesian uncertainty analysis of the corresponding regression model. It is shown that under certain assumptions both analyses yield the same results but this is not true in general. Some simple examples are given which illustrate the similarities and differences between the two approaches.

Elster, Clemens; Toman, Blaza

2011-10-01

258

Rheology of dispersions of xanthan gum, locust bean gum and mixed biopolymer gel with silicon dioxide nanoparticles.  

PubMed

Mixed xanthan gum (XG) and locust bean gum (LBG) biopolymers form thermally reversible gels of interest in tissue engineering and drug delivery. 1% solutions of XG, LBG and 1:1 ratio XG/LBG mixed gels (LX) containing silicon dioxide (SiO2) nanoparticles were rheologically characterized with respect to nanoparticle concentration and temperature. 10% nanoparticles in XG created larger domains of associated polymer, resulting in enhanced viscosity and viscoelastic moduli. In LBG with 10% particles, transient viscosity and a gel-sol transition occurred due to particle bridging and aggregation. In the LX gel, 10% SiO2 particles caused an increase in elasticity. When ramping temperature from 25°C to 85°C, the complex modulus for all solutions containing 10% SiO2 was relatively constant, indicating that nanoparticles counteracted the effect of temperature on the material properties. Understanding the influence of nanoparticle loading on material properties is necessary for biopolymer material development where property prediction and control are critical. PMID:25579932

Kennedy, Jordan R M; Kent, Katherine E; Brown, Jennifer R

2015-03-01

259

Reactivity recovery of guar gum coupled mZVI by means of enzymatic breakdown and rinsing  

NASA Astrophysics Data System (ADS)

Microscale zerovalent iron (mZVI) reduces chlorinated aliphatic hydrocarbons (CAHs) to harmless compounds, but the sedimentation of the mZVI particles in the injection fluid limits the injectability of the particles during field applications. In this study, mZVI particles in suspension were stabilized by green polymer guar gum, which had a positive impact on mZVI stability, but decreased the reactivity of the particles towards CAHs by 1 to 8 times. Guar gum (GG) was found to adsorb onto the mZVI surface, inhibiting contact between the chlorinated compounds and the reactive iron surface. Indications were found for intermolecular hydrogen bonding between mZVI and the guar gum. Subsequent addition of commercially available enzymes resulted in the cleavage of the polysaccharide guar gum into lower molecular fragments, but not in improved reactivity. The reactivity recovery of guar gum coupled mZVI was recovered after intensive rinsing of the iron particles, removing the guar gum fragments from the particles. Overall, this study shows that CAHs can be treated efficiently by guar gum stabilized mZVI after reactivation by means of enzymatic breakdown and rinsing.

Velimirovic, Milica; Chen, Hong; Simons, Queenie; Bastiaens, Leen

2012-11-01

260

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

SciTech Connect

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.

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

2013-01-15

261

Advances in identification of plant gums in cultural heritage by thermally assisted hydrolysis and methylation.  

PubMed

Plant gums are present in works of art as binding media for watercolours and adhesives for cellulosic substrates. Thermally assisted hydrolysis and methylation (THM) in combination with analytical pyrolysis coupled to GC/MS has been applied to the characterisation of plant gums typically used in artworks. THM products from standard samples of arabic gum, tragacanth gum and cherry gum were characterised. The main products identified are permethylated and partially methylated aldonic acids, characteristic of specific epimeric sugars. Aldonic acids were formed by alkaline hydrolysis of free reducing sugars and of reducing polysaccharide terminal groups, while methylation occurs during pyrolysis. The presence of these characteristic markers allows gum identification. A systematic analysis of all the parameters that can affect the marker yields was performed. In particular, the influence of pyrolysis temperature, reagent concentration and contact time between tetramethylammonium hydroxide and sample were studied, and different kinds of sample preparation procedures were tested. Some analyses on real watercolours were performed, and gum binders were classified using the peak area ratio of the main monosaccharide markers. PMID:20012903

Riedo, Chiara; Scalarone, Dominique; Chiantore, Oscar

2010-02-01

262

Long-term effects of guar gum in subjects with non-insulin-dependent diabetes mellitus.  

PubMed

The effects of 15 g guar gum/d on glycemic control, lipids, and insulin secretion were studied in 15 (8 male, 7 female) diet-treated subjects with non-insulin-dependent diabetes mellitus for 48 wk. Mean age (+/- SD) was 60 +/- 2 y (range 45-70 y), body mass index (in kg/m2) 28.6 +/- 0.9 (range 21.6 +/- 39.2), and duration of diabetes 6 +/- 1 y (range 2-14 y). Guar gum was preceded and followed by 8-wk placebo periods. Guar gum improved long-term glycemic control, postprandial glucose tolerance and lipid concentrations. The C-peptide response to a test meal increased by time during guar gum treatment, whereas the insulin response remained unchanged. This indicates that insulin secretion is enhanced by guar gum as reflected by increased C-peptide. A decreased molar ratio of insulin to C-peptide suggests that guar gum may increase hepatic insulin extraction. In conclusion, guar gum has favorable long-term effects on glycemic control and lipid concentrations. PMID:8397484

Groop, P H; Aro, A; Stenman, S; Groop, L

1993-10-01

263

[Sugar of substitute stevioside in chewing gum: comparative double blind controllable study].  

PubMed

In double blind controllable study on 126 volunteers - students of medical academy - influence on ?? the mixed saliva of 5 kinds of chewing gums with the different contents of substitute of sugar as xylitol and sorbitol, and also the chewing sweets R.O.C.S., two kinds of chewing gums containing a basis with substitute of sugar stevioside (1.25 and 2.5%) and placebo (a basis without additives) were investigated. Products chewed within 10 minutes. In one of groups surveyed such chewing was preceded with rinsing a mouth by a test solution of saccharose. ?? determined within 30 minutes. At chewing gums with substitute of sugar displacement ?? the mixed saliva in the alkaline side was revealed a different degree. Thus gums with stevioside did not concede and even surpassed in this action of chewing gums with other substitutes of sugar. In comparison with placebo chewing gums and sweets restored acid-alkaline balance of oral cavities faster. Hence, use of stevioside in structure of chewing gum allows at preservation of its positive actions in oral cavity essentially to reduce concentration substitute of sugar and, hence, its collateral action by an organism. PMID:21378715

Rumiantsev, V A; Beliaev, V V; Zubtsov, V A; Esaian, L K; Namestnikova, I V

2011-01-01

264

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

PubMed Central

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

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

2014-01-01

265

Evaluation of Albizia procera gum as compression coating material for colonic delivery of budesonide.  

PubMed

The purpose of this research was to develop and evaluate Albizia procera gum as compression-coating polymer for colonic delivery of budesonide. Tablets were prepared by direct compression method using spray-dried lactose and microcrystalline cellulose as filler binders. The compatibility between the drug and the polymer was studied through TGA and FTIR spectroscopy. In vitro drug release were studied in dissolution media with or without 2% rat cecal contents while in vivo X-ray study was conducted on rabbits. The results indicate that procera gum and the drug were compatible with each other and tablet coated with procera gum was suitable for colonic delivery of drugs. PMID:23916644

Pachuau, Lalduhsanga; Mazumder, Bhaskar

2013-10-01

266

Nonionic gelation agents prepared from hydroxypropyl guar gum.  

PubMed

Nonionic gels were prepared from hydroxypropyl guar gum (HPG) with different molar substitution degrees by crosslinking with ethylene glycol diglycidyl ether (EGDE). FTIR and solid-state NMR spectroscopy revealed that the crosslinking degree of HPG gels increased with the amount of EGDE used during the reaction; this result was also confirmed by the water mobility in the swollen gels. Rheological characterization revealed behaviors typical of true gels, and their viscoelastic behaviors strongly depended on the crosslinking degree. The HPG gels absorbed buffers, aqueous saline, and water, and the absorption was not affected by the ionic strength or pH of the solution. In addition, HPG gels with high crosslinking degrees and molar substitution degrees exhibited gelation ability toward protic organic solvents such as methanol, ethanol, and 1-propanol. These HPG gels may find application as gelation agents for many industrial uses. PMID:25498682

Kono, Hiroyuki; Hara, Hideyuki; Hashimoto, Hisaho; Shimizu, Yuuichi

2015-03-01

267

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

E-print Network

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 ...

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

268

Compounds from Gum Ammoniacum with Acetylcholinesterase Inhibitory Activity  

PubMed Central

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

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

2013-01-01

269

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

ERIC Educational Resources Information Center

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.

Witter, A. E.

2005-01-01

270

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

SciTech Connect

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.

HOLDEN,N.E.

2007-07-23

271

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

PubMed

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

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

2012-01-01

272

Magnetism  

NSDL National Science Digital Library

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.

University Corporation for Atmospheric Research Windows to the Universe team

2007-12-12

273

The Effects of Xylitol-containing Chewing Gums on Dental Plaque and Acidogenic Potential  

Microsoft Academic Search

The aim of this study was to test the hypothesis that the chewing of xylitol- or xylitol\\/sorbitol-containing chewing gum reduces plaque formation and the acidogenic potential of dental plaque. Thirty healthy volunteers aged from 19 to 28 yrs were randomly allocated to one of three test groups, chewing either xylitol-, xylitol\\/sorbitol-, or sucrose-sweetened gums. A three-day plaque accumulation period of

A. Aa. Scheie; O. Fejerskov; B. Danielsen

1998-01-01

274

Acacia gum and its use by bushbabies, Galago senegalensis (Primates: Lorisidae)  

Microsoft Academic Search

Lesser bushbabies (Galago senegalensis moholi)were studied by radiotracking over a 2-year period (August 1975 to August 1977)at a thornveld study site in the Northern Transvaal, South Africa. It was confirmed that the diet consisted exclusively of\\u000a plant exudates (gums) and arthropods;available fruits were never eaten. The gums were taken from the trunks and branches of Acaciatrees, particularly from Acacia karroo(the

S. K. Bearder; R. D. Martin

1980-01-01

275

Evaluation of the uncertainty of electrical impedance measurements: the GUM and its Supplement 2  

NASA Astrophysics Data System (ADS)

Electrical impedance is not a scalar but a complex quantity. Thus, evaluation of the uncertainty of its value involves a model whose output is a complex. In this paper the comparison of the evaluation of the uncertainty of the measurement of the electrical impedance of a simple electric circuit using the GUM and using a Monte Carlo method according to the Supplement 2 of the GUM is presented.

Ramos, Pedro M.; Janeiro, Fernando M.; Girão, Pedro S.

2015-02-01

276

Nicotine-containing chewing gum as an anti-smoking aid  

Microsoft Academic Search

Chewing gum containing nicotine or placebo was given to smokers attending an anti-smoking clinic. During a one week double-blind study subjects receiving nicotine smoked less and chewed less gum than those receiving placebo. The difference in tobacco consumption between the two treatment groups was most apparent among previous heavy smokers. During a 6 month follow-up phase all subjects were offered

B. Brantmark; P. Ohlin; H. Westling

1973-01-01

277

Compaction, compression and drug release characteristics of xanthan gum pellets of different compositions  

Microsoft Academic Search

Compaction and compression of xanthan gum (XG) pellets were evaluated and drug release from tablets made of pellets was characterised. Three formulations were prepared by extrusion–spheronisation and included, among other excipients, diclofenac sodium (Dic Na), at 10% (w\\/w); xanthan gum, at 16% (w\\/w); and one of three different fillers (lactose monohydrated (LAC), tribasic calcium phosphate (TCP) and ?-cyclodextrin (?-CD)), at

Helton Santos; Francisco Veiga; M Pina; João José Sousa

2004-01-01

278

GUM Analysis for SIMS Isotopic Ratios in BEP0 Graphite Qualification Samples, Round 2  

SciTech Connect

This report describes GUM calculations for TIMS and SIMS isotopic ratio measurements of reactor graphite samples. These isotopic ratios are used to estimate reactor burn-up, and currently consist of various ratios of U, Pu, and Boron impurities in the graphite samples. The GUM calculation is a propagation of error methodology that assigns uncertainties (in the form of standard error and confidence bound) to the final estimates.

Gerlach, David C.; Heasler, Patrick G.; Reid, Bruce D.

2009-01-01

279

Studies on the antioxidative activities of Hsian-tsao (Mesona procumbens Hemsl) leaf gum.  

PubMed

This study aimed at evaluating the antioxidative activity of crude hsian-tsao leaf gum extracted by sodium bicarbonate solutions and precipitated by 70% ethanol. The antioxidative activities, including the radical-scavenging effects, Fe(2+)-chelating ability, and reducing power as well as the inhibition of FeSO(4)-H(2)O(2)-induced malondialdehyde formation in rat tissue homogenate were studied in vitro. It was found that the antioxidative effect provided by hsian-tsao leaf gum was strongly concentration dependent. In general, the antioxidative activity increased with increasing gum concentration, to a certain extent, and then leveled off with further increase in gum concentration. A concentrtaion-dependent kinetics for the rate of change in antioxidative activity was proposed. The antioxidative activity constant (k) and the half-inhibition concentration (IC(50)) for each antioxidative reaction studied were calculated. From a comparison of the IC(50) values for different antioxidative reactions, it seemed that hsian-tsao leaf gum was more effective in scavenging superoxide radicals than chelating Fe(2+) or scavenging alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) radicals. As compared to the commercial antioxidants, hsian-tsao leaf gum showed less scavenging effect on the DPPH radical and reducing power but better superoxide radical-scavenging effect and Fe(2+)-chelating ability than alpha-tocopherol and BHT. PMID:11262057

Lai, L S; Chou, S T; Chao, W W

2001-02-01

280

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

PubMed Central

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

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

2012-01-01

281

Pharmacological properties of guggulsterones, the major active components of gum guggul.  

PubMed

Oleo gum resin secreted by Commiphora mukul, also known as gum guggul, has been used widely as an ayurvedic drug. Commiphora mukul is a short thorny shrub that is native to the Indian subcontinent. Oleo gum resin extracted by incision of the bark is a very complex mixture of gum, minerals, essential oils, terpenes, sterols, ferrulates, flavanones and sterones. Its active constituents, the Z- and E-guggulsterones, have been demonstrated to exhibit their biological activities by binding to nuclear receptors and modulating the expression of proteins involved in carcinogenic activities. Guggulsterones have also been reported to regulate gene expression by exhibiting control over other molecular targets including transcription factors such as nuclear factor (NF)-?B, signal transducer and activator of transcription (STAT) and steroid receptors. Considerable scientific evidence indicates the use of gum guggul as a therapeutic agent in the treatment of inflammation, nervous disorders, hyperlipidaemia and associated cardiac disorders such as hypertension and ischaemia, skin disorders, cancer and urinary disorders. This review highlights the taxonomic details, phytochemical properties and pharmacological profile of gum guggul. PMID:22388973

Shah, Rohan; Gulati, Vandana; Palombo, Enzo A

2012-11-01

282

Influence of gum tragacanth on the physicochemical and rheological properties of kashk.  

PubMed

In this study, the physicochemical properties of a low-fat dried yogurt paste (kashk) were determined, and the effects of different concentrations (0, 0·1, 0·3 and 0·5% w/w) of gum tragacanth exudates from Astragalus gossypinus on the stability and texture of the samples were investigated by measuring amount of syneresis, turbidity, particle size distribution (PSD), flow behaviour and viscoelastic properties. The flow behaviour index was not very sensitive to the concentration of gum, while a remarkable concentration dependency of the power-law consistency coefficient and Herschel-Bulkley yield stress was observed. The initial increase in the gum concentration at 0·1 and 0·3% levels led to a higher degree of syneresis, which was related to the depletion flocculation mechanism. However, the reduced amount of syneresis in samples containing 0·5% gum tragacanth was attributed to the significant increase in viscosity of the continuous phase, which is also accompanied by trapping of the aggregated casein particles. The presence of 3% salt in the samples may have led to the neutralization of charges on the surface of gum tragacanth; consequently, the non-adsorbing behaviour of high-ionic-strength polysaccharides inhibited the formation of electrostatic protein-polysaccharide complexes. Furthermore, maximum values of polydispersity, syneresis and tan ? at high frequencies were found in samples containing 0·1% gum tragacanth. PMID:23171586

Shiroodi, Setareh Ghorban; Mohammadifar, Mohammad Amin; Gorji, Elham Ghorbani; Ezzatpanah, Hamid; Zohouri, Nilofar

2012-02-01

283

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

PubMed Central

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

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

1998-01-01

284

Biological activity of some naturally occurring resins, gums and pigments against in vitro LDL oxidation.  

PubMed

Naturally occurring gums and resins with beneficial pharmaceutical and nutraceutical properties were tested for their possible protective effect against copper-induced LDL oxidation in vitro. Chiosmastic gum (CMG) (Pistacia lentiscus var. Chia resin) was the most effective in protecting human LDL from oxidation. The minimum and maximum doses for the saturation phenomena of inhibition of LDL oxidation were 2.5 mg and 50 mg CMG (75.3% and 99.9%, respectively). The methanol/water extract of CMG was the most effective compared with other solvent combinations. CMG when fractionated in order to determine a structure-activity relationship showed that the total mastic essential oil, collofonium-like residue and acidic fractions of CMG exhibited a high protective activity ranging from 65.0% to 77.8%. The other natural gums and resins (CMG resin 'liquid collection', P. terebinthus var. Chia resin, dammar resin, acacia gum, tragacanth gum, storax gum) also tested as above, showed 27.0%-78.8% of the maximum LDL protection. The other naturally occurring substances, i.e. triterpenes (amyrin, oleanolic acid, ursolic acid, lupeol, 18-a-glycyrrhetinic acid) and hydroxynaphthoquinones (naphthazarin, shikonin and alkannin) showed 53.5%-78.8% and 27.0%-64.1% LDL protective activity, respectively. The combination effects (68.7%-76.2% LDL protection) of ursolic-, oleanolic- and ursodeoxycholic- acids were almost equal to the effect (75.3%) of the CMG extract in comparable doses. PMID:12748987

Andrikopoulos, Nikolaos K; Kaliora, Andriana C; Assimopoulou, Andreana N; Papapeorgiou, Vassilios P

2003-05-01

285

Glucose absorption, hormonal release and hepatic metabolism after guar gum ingestion.  

PubMed

Six non-anaesthetized Large White pigs (mean body weight 59 +/- 1.7 kg) were fitted with permanent catheters in the portal vein, the brachiocephalic artery and the right hepatic vein and with electromagnetic flow probes around the portal vein and the hepatic artery. The animals were provided a basal none-fibre diet (diet A) alone or together with 6% guar gum (diet B) or 15% purified cellulose (diet C). The diets were given for 1 week and according to a replicated 3 x 3 latin-square design. On the last day of each adaptation period test meals of 800 g were given prior to blood sampling. The sampling was continued for 8 h. Guar gum strongly reduced the glucose absorption as well as the insulin, gastric inhibitory polypeptide (GIP) and insulin-like growth factor-1 (IGF-1) production. However, the reduction in peripheral blood insulin levels caused by guar gum was not associated with a change in hepatic insulin extraction. IGF-1 appeared to be strongly produced by the gut. The liver had a net uptake of the peptide. Ingestion of guar gum increased the hepatic extraction coefficient of gut produced IGF-1. Guar gum ingestion also appeared to decrease pancreatic glucagon secretion. Cellulose at the level consumed had very little effect on the parameters considered. It is suggested that the modulation of intestinal mechanisms by guar gum was sufficient to mediate the latter internal metabolic effects. PMID:1315555

Simões Nunes, C; Malmlöf, K

1992-01-01

286

Gum arabic/starch/maltodextrin/inulin as wall materials on the microencapsulation of rosemary essential oil.  

PubMed

The effects of the partial or total replacement of gum arabic by modified starch, maltodextrin and inulin on the characteristics of rosemary essential oil microencapsulated by spray drying were evaluated in this study. The lowest level of water absorption under conditions of high relative humidity was observed in treatments containing inulin. The wettability property of the powders was improved by the addition of inulin. The total replacement of gum arabic by modified starch or a mixture of modified starch and maltodextrin (1:1, m/m) did not significantly affect the efficiency of encapsulation, although higher Tg values were exhibited by microcapsules prepared using pure gum arabic or gum arabic and inulin. 1,8-cineol, camphor and ?-pinene were the main components identified by gas chromatography in the oils extracted from the microcapsules. The particles had smoother surfaces and more folds when gum arabic or inulin was present. Larger particles were observed in the powders prepared with pure gum arabic or modified starch. PMID:24299808

Fernandes, Regiane Victória de Barros; Borges, Soraia Vilela; Botrel, Diego Alvarenga

2014-01-30

287

Glucose absorption, hormonal release and hepatic metabolism after guar gum ingestion  

NASA Technical Reports Server (NTRS)

Six non-anaesthetized Large White pigs (mean body weight 59 +/- 1.7 kg) were fitted with permanent catheters in the portal vein, the brachiocephalic artery and the right hepatic vein and with electromagnetic flow probes around the portal vein and the hepatic artery. The animals were provided a basal none-fibre diet (diet A) alone or together with 6% guar gum (diet B) or 15% purified cellulose (diet C). The diets were given for 1 week and according to a replicated 3 x 3 latin-square design. On the last day of each adaptation period test meals of 800 g were given prior to blood sampling. The sampling was continued for 8 h. Guar gum strongly reduced the glucose absorption as well as the insulin, gastric inhibitory polypeptide (GIP) and insulin-like growth factor-1 (IGF-1) production. However, the reduction in peripheral blood insulin levels caused by guar gum was not associated with a change in hepatic insulin extraction. IGF-1 appeared to be strongly produced by the gut. The liver had a net uptake of the peptide. Ingestion of guar gum increased the hepatic extraction coefficient of gut produced IGF-1. Guar gum ingestion also appeared to decrease pancreatic glucagon secretion. Cellulose at the level consumed had very little effect on the parameters considered. It is suggested that the modulation of intestinal mechanisms by guar gum was sufficient to mediate the latter internal metabolic effects.

Simoes Nunes, C.; Malmlof, K.

1992-01-01

288

Pasting properties of Tamarind (Tamarindus indica) kernel powder in the presence of Xanthan, Carboxymethylcellulose and Locust bean gum in comparison to Rice and Potato flour.  

PubMed

Effects of addition of different levels of gums (xanthan, carboxymethylcellulose and locust bean gum) on the pasting properties of tamarind kernel, potato and rice flour were studied by using Rapid Visco-Analyzer (RVA). Tamarind kernel powder (TKP) varied significantly (P?gum mixtures were dependent upon the concentration and type of the gums. Peak, breakdown and final viscosity increased with increase in gum concentration in the flour/gum mixture, but the effect was more pronounced for rice and potato flour than for TKP which showed much lower viscosity responses to all of the gums. Among the three gums studied, the increase in viscosity was significantly higher with addition of locust bean gum followed by xanthan while the lowest was observed with carboxymethylcellulose. PMID:24425986

Kaur, Maninder; Sandhu, Kawaljit Singh; Kaur, Jasmeen

2013-08-01

289

Hydrocolloids in emulsions: particle size distribution and interfacial activity  

Microsoft Academic Search

The emulsification properties of 14 hydrocolloid gums (propylene glycol alginate, gellan, carrageenan, pectin, methylcellulose, microcrystalline cellulose, gum arabic, locust bean gum, guar, xanthan, mustard, flaxseed, fenugreek, oat) were investigated. Gum dispersions were prepared in water (0.5%) and emulsified with 40% oil using a Polytron homogenizer. Emulsion stability was determined by centrifugation and storage time, surface and interfacial tension by Du

X Huang; Y Kakuda; W Cui

2001-01-01

290

Magnetism  

NSDL National Science Digital Library

This radio broadcast discusses the history of magnetism from the time of its discovery by an apocryphal Greek sheperd until the late 16th century and the work of William Gilbert. There is also discussion of who pioneered the study of magnetism, what theories they constructed from its curious abilities, and how the power of the magnet was brought out of the realm of magic and into the service of science. The broadcast concludes with a discussion of why magnetism is still mysterious and how the modern search for the single magnetic pole, or magnetic monopole, could provide a fundamental unit of magnetism, essential for ultimate explanation. The broadcast is 41 minutes and 45 seconds in length.

291

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

NASA Astrophysics Data System (ADS)

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.

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

2005-06-01

292

Changes in electrical energy requirements to operate an ice cream freezer as a function of sweeteners and gums  

SciTech Connect

Changes in electrical energy required to operate a continuous freezer were monitored for various ice cream formulae. Ice cream formulae consisted of nine different combinations of sucrose, 36 DE corn syrup, and 42 high fructose corn syrup as well as two ratios of guar gum to locust bean gum. Within the same sweetening system, a mix high in locust bean gum tended to have a lower energy demand than mix with large amounts of guar gum. This was especially pronounced in mixes with 50% 42 high fructose corn syrup and/or 50% 36 DE corn syrup solids.

Smith, D.E.; Bakshi, A.S.; Gay, S.A.

1985-01-01

293

Identification of two additives, locust bean gum (E-410) and guar gum (E-412), in food products by DNA-based methods.  

PubMed

Locust bean gum (E-410) and guar gum (E-412) are high molecular weight galactomannans used by the food industry as versatile food additives. The compounds, although chemically closely related, do not have the same functional properties when used in foods, and the substitution or unadvertised addition of either could change the desired qualities of the product. Analytical discrimination between E-410 and E-412 is technically difficult since they only differ in their galactose: mannose ratios, being 1 : 4 and 1 : 2 for locust bean gum and guar gum, respectively. A qualitative DNA-based method is reported for the authentication of additives E-410 and E-412 in finished food products (ice cream, dehydrated desserts, milk derivatives, dehydrated soups, salad dressing, marmalade and meat) from small quantities of food. DNA sequences from the nuclear ribosomal spacers of Ceratonia siliqua and Cyamopsis tetragonoloba, the plant sources of E-410 and E-412, respectively, were used to design polymerase chain reaction primers specific for each additive (PA23/PA21 and PG22/PG21). Twenty-two foods were analysed for the presence of E-410 and E-412 additives by this single-step polymerase chain reaction-based method. Positive DNA amplifications with the E-410 and/or E-412 primers were obtained in all 19 samples reported to contain either additive. PMID:15370834

Urdiain, M; Doménech-Sánchez, A; Albertí, S; Benedí, V J; Rosselló, J A

2004-07-01

294

Influence of xanthan gum on the structural characteristics of myofibrillar proteins treated by high pressure.  

PubMed

The effects of xanthan gum on the structural modifications of myofibrillar proteins (0.3 M NaCl, pH 6) induced by high pressure (200, 400, and 600 MPa, 6 min) were investigated. The changes in the secondary and tertiary structures of myofibrillar proteins were analyzed by circular dichroism. The protein denaturation was also evaluated by differential scanning calorimetry. Likewise, the protein surface hydrophobicity and the solubility of myofibrillar proteins were measured. High pressure (600 MPa) induced the loss of ?-helix structures and an increase of ?-sheet structures. However, the presence of xanthan gum hindered the former mechanism of protein denaturation by high pressure. In fact, changes in the secondary (600 MPa) and the tertiary structure fingerprint of high-pressure-treated myofibrillar proteins (400 to 600 MPa) were observed in the presence of xanthan gum. These modifications were confirmed by the thermal analysis, the thermal transitions of high-pressure (400 to 600 MPa)-treated myofibrillar proteins were modified in systems containing xanthan gum. As consequence, the high-pressure-treated myofibrillar proteins with xanthan gum showed increased solubility from 400 MPa, in contrast to high-pressure treatment (600 MPa) without xanthan gum. Moreover, the surface hydrophobicity of high-pressure-treated myofibrillar proteins was enhanced in the presence of xanthan gum. These effects could be due to the unfolding of myofibrillar proteins at high-pressure levels, which exposed sites that most likely interacted with the anionic polysaccharide. This study suggests that the role of food additives could be considered for the development of meat products produced by high-pressure processing. PMID:25656483

Villamonte, Gina; Jury, Vanessa; Jung, Stéphanie; de Lamballerie, Marie

2015-03-01

295

Evaluation of Gum of Moringa oleifera as a Binder and Release Retardant in Tablet Formulation.  

PubMed

The present study was undertaken to find out the potential of gum from Moringa oleifera to act as a binder and release retardant in tablet formulations. The effect of calcium sulphate dihydrate (water insoluble) and lactose (water soluble) diluent on the release of propranolol hydrochloride was studied. The DSC thermograms of drug, gum and mixture of gum/drug indicated no chemical interaction. Tablets (F1, F2, F3, and F4) were prepared containing calcium sulphate dihydrate as diluent, propranolol hydrochloride as model drug using 10%, 8%, 6% and 4% w/v of gum solution as binder. Magnesium stearate was used as lubricant. Physical and technological properties of granules and tablets like flow rate, Carr index, Hausner ratio, angle of repose, hardness, friability and disintegration time were determined and found to be satisfactory. Tablets were prepared by wet granulation method containing calcium sulphate dihydrate as excipient, propranolol hydrochloride as model drug using 10%, 20% and 30% of gum as release retardant, magnesium stearate was used as lubricant. Similarly tablets were prepared replacing lactose with calcium sulphate dihydrate. Despite of the widely varying physico-chemical characteristics of the excipients, the drug release profiles were found to be similar. The drug release increased with increasing proportions of the excipient and decreased proportion of the gum irrespective of the solubility characteristics of the excipient. The values of release exponent 'n' are between 0.37 and 0.54. This implies that the release mechanism is Fickian. There is no evidence that the dissolution or erosion of the excipient has got any effect on the release of the drug. The t(50%) values for tablets containing calcium sulphate dihydrate were on an average 10%-15% longer than the tablets containing lactose as excipient. These relatively small differences in t(50%) values suggest that the nature of excipient used appeared to play a minor role in regulating the release, while the gum content was a major factor. PMID:21394258

Panda, D S; Choudhury, N S K; Yedukondalu, M; Si, S; Gupta, R

2008-09-01

296

Mutans streptococci dose response to xylitol chewing gum.  

PubMed

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 at baseline, 5 wks, and 6 mos, and were cultured on modified Mitis Salivarius agar for mutans streptococci and on blood agar for total culturable flora. At 5 wks, mutans streptococci levels in plaque were 10x lower than baseline in G3 and G4 (P = 0.007/0.003). There were no differences in saliva. At 6 mos, mutans streptococci in plaque for G3 and G4 remained 10x lower than baseline (P = 0.007/0.04). Saliva for G3 and G4 was lower than baseline by 8 to 9x (P = 0.011/0.038). Xylitol at 6.44 g/day and 10.32 g/day reduces mutans streptococci in plaque at 5 wks, and in plaque and unstimulated saliva at 6 mos. A plateau effect is suggested between 6.44 g and 10.32 g xylitol/day. PMID:16434738

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

2006-02-01

297

Effect of molecular configuration of Xanthan gum drage reduction  

NASA Astrophysics Data System (ADS)

Drag reduction in turbulent pipe flow has been studied using dilute xanthan gum solutions. The primary goal of the studies was torelate the molecular configuration of xanthan in solutions of varying ionic strength to its effectiveness as a drag reducer. Xanthan solutions of various concentrations (10-250 wppm) in glycerine/water (12.5/87.5) and with 0.5%NaCl, added were studied over a wide Reynolds number range (1000< Re<2×104). A Rheometrics Fluids Rheometer was used to characterize the solutions in steady shear and to perform transient start-up experiments. The steady shear viscosity and transient shear stress overshoot are both significantly reduced with the addition of salt to the solution, indicating that the xanthan configuration is altered. The form of the drag reduction is similar to that which is expected for an extended molecule in dilute solution. For a given xanthan concentration, the drag reduction at high Reynolds numbers is also much lower in salt solution. Combining a knowledge of the molecular structure of xanthan and the results of recent analytical studies by several research groups, with the rheological data of this study, it is possible to speculate as to the configuration change which occurs with the addition of salt and to relate that to its effect on drag reduction. With this information, some insight into the mechanisms for drag reduction in semi-rigid polymer systems is obtained.

Rochefort, Skip; Middleman, Stanley

1986-01-01

298

Final report of the safety assessment of Acacia catechu gum, Acacia concinna fruit extract, Acacia dealbata leaf extract, Acacia dealbata leaf wax, Acacia decurrens extract, Acacia farnesiana extract, Acacia farnesiana flower wax, Acacia farnesiana gum, Acacia senegal extract, Acacia senegal gum, and Acacia senegal gum extract.  

PubMed

These ingredients are derived from various species of the acacia plant. Only material derived from Acacia senegal are in current use according to industry data. The concentration at which these ingredients are reported to be used ranges from 9% in mascara to 0.0001% in tonics, dressings, and other hair-grooming aids. Gum arabic is a technical name for Acacia Senegal Gum. Gum arabic is comprised of various sugars and glucuronic acid residues in a long chain of galactosyl units with branched oligosaccharides. Gum arabic is generally recognized as safe as a direct food additive. Little information is available to characterize the extracts of other Acacia plant parts or material from other species. Acacia Concinna Fruit Extract was generally described as containing saponins, alkaloids, and malic acid with parabens and potassium sorbate added as preservatives. Cosmetic ingredient functions have been reported for Acacia Decurrens Extract (astringent; skin-conditioning agent--occlusive) and Acacia Farnesiana Extract (astringent), but not for the other Acacias included in this review. Toxicity data on gum arabic indicates little or no acute, short-term, or subchronic toxicity. Gum arabic is negative in several genotoxicity assays, is not a reproductive or developmental toxin, and is not carcinogenic when given intraperitoneally or orally. Clinical testing indicated some evidence of skin sensitization with gum arabic. The extensive safety test data on gum arabic supports the safety of Acacia Senegal Gum and Acacia Senegal Gum Extract, and it was concluded that these two ingredients are safe as used in cosmetic formulations. It was not possible, however, to relate the data on gum arabic to the crude Acacias and their extracts from species other than Acacia senegal. Therefore, the available data were considered insufficient to support the safety of Acacia Catechu Gum, Acacia Concinna Fruit Extract, Acacia Dealbata Leaf Extract, Acacia Dealbata Leaf Wax, Acacia Decurrens Extract, Acacia Farnesiana Extract, Acacia Farnesiana Flower Wax, Acacia Farnesiana Gum, and Acacia Senegal Extract in cosmetic products. The additional data needed to complete the safety assessment for these ingredients include (1) concentration of use; (2) identify the specific chemical constituents, and clarify the relationship between crude Acacias and their extracts and the Acacias and their extracts that are used as cosmetic ingredients; (3) data on contaminants, particularly relating to the presence of pesticide residues, and a determination of whether Acacia melanoxylon is used in cosmetics and whether acamelin (a quinone) and melacacidin (a flavin) are present in the Acacias that are being used; (4) skin sensitization study (i.e., dose response to be determined); (5) contact urticaria study at use concentration; and (6) ultraviolet (UV) absorption spectrum; if there is significant absorbance in the UVA or UVB range, then a photosensitization study may be needed. It was also noted that other data may be needed after clarification of the chemical constituents of the Acacia-derived ingredients. PMID:16422266

2005-01-01

299

Synthesis of oxidized guar gum by dry method and its application in reactive dye printing.  

PubMed

The aim of this study was to prepare oxidized guar gum with a simple dry method, basing on guar gum, hydrogen peroxide and a small amount of solvent. To obtain a product with suitable viscosity for reactive dye printing, the effects of various factors such as the amount of oxidant and solvent, reaction temperature and time were studied with respect to the viscosity of reaction products. The product was characterized by Fourier transform infrared spectroscopy, size exclusion chromatography, scanning electron microscopy and differential scanning calorimetry. The hydrated rate of guar gum and oxidized guar gum was estimated through measuring the required time when their solutions (1%, w/v) reached the maximum viscosity. The effects of the salt concentration and pH on viscosity of the resultant product were studied. The mixed paste containing oxidized guar gum and carboxymethyl starch was prepared and its viscosity was determined by the viscometer. The rheological property of the mixed paste was appraised by the printing viscosity index. In addition, the applied effect of mixed paste in reactive dye printing was examined by assessing the fabric stiffness, color yield and sharp edge to the printed image in comparison with sodium alginate. And the results indicated that the mixed paste could partially replace sodium alginate as thickener in reactive dye printing. The study also showed that the method was low cost and eco-friendly and the product would have an extensive application in reactive dye printing. PMID:21925204

Gong, Honghong; Liu, Mingzhu; Zhang, Bing; Cui, Dapeng; Gao, Chunmei; Ni, Boli; Chen, Jiucun

2011-12-01

300

Optimization of enzymatic hydrolysis of guar gum using response surface methodology.  

PubMed

Guar gum is a polysaccharide obtained from guar seed endosperm portion. Enzymatically hydrolyzed guar gum is low in viscosity and has several health benefits as dietary fiber. In this study, response surface methodology was used to determine the optimum conditions for hydrolysis that give minimum viscosity of guar gum. Central composite was employed to investigate the effects of pH (3-7), temperature (20-60 °C), reaction time (1-5 h) and cellulase concentration (0.25-1.25 mg/g) on viscosity during enzymatic hydrolysis of guar (Cyamopsis tetragonolobus) gum. A second order polynomial model was developed for viscosity using regression analysis. Results revealed statistical significance of model as evidenced from high value of coefficient of determination (R(2)?=?0.9472) and P?gum as potential source of soluble dietary fiber for human health benefits. PMID:25114354

Mudgil, Deepak; Barak, Sheweta; Khatkar, B S

2014-08-01

301

Green stabilization of microscale iron particles using guar gum: bulk rheology, sedimentation rate and enzymatic degradation.  

PubMed

Guar gum can be used to effectively improve stability and mobility of microscale zerovalent iron particles (MZVI) used in groundwater remediation. Guar gum is a food-grade, environment friendly natural polysaccharide, which is often used as thickening agent in a broad range of food, pharmaceutical and industrial applications. Guar gum solutions are non-Newtonian, shear thinning fluids, characterized by high viscosity in static conditions and low viscosity in dynamic conditions. In particular, the high zero shear viscosity guarantees the MZVI dispersion stability, reducing the sedimentation rate of the particles thus enabling its storage and field operations. In this work, a comprehensive rheological characterization of guar gum-based slurries of MZVI particles is provided. First, we derived a model to link the bulk shear viscosity to the concentration of guar gum and then we applied it for the derivation of a modified Stokes law for the prediction of the sedimentation rate of the iron particles. The influence of the preparation procedure (cold or hot dissolution and high shear processing) on the viscosity and on the stability of the suspensions was then assessed. Finally, the dosage and concentration of enzymes - an environment friendly breaker--were studied for enhancing and controlling the degradation kinetics of the suspensions. The derived empirical relationships can be used for the implementation of an iron slurry flow and transport model and for the design of full scale injection interventions. PMID:24594029

Gastone, Francesca; Tosco, Tiziana; Sethi, Rajandrea

2014-05-01

302

Electrically conducting silver/guar gum/poly(acrylic acid) nanocomposite.  

PubMed

This article describes the synthesis of an electrically conducting silver/guar gum/poly(acrylic acid) nanocomposite hydrogel. The synthesis process started with grafting acrylic acid monomers onto the natural polymer guar gum by the use of ammonium persulphate as a free radical initiator in acid medium. Guar gum/poly(acrylic acid) graft copolymer was separated from the polymerization medium, purified and subjected to crosslinking treatment, using alkaline epichlorohydrin as a crosslinking agent. Silver nitrate solution was added during the crosslinking treatment in varying concentrations, that the reaction conditions affect crosslinking of guar gum/poly(acrylic acid) graft copolymer to a hydrogel, as well as reduction of silver nitrate to silver nanoparticles, giving rise to the formation of silver/guar gum/poly(acrylic acid) nanocomposite. Factors affecting the grafting reaction as well as those affecting the crosslinking/reduction treatment were optimized. The so synthesized nanocomposite hydrogel samples were fully characterized, regarding their contents of silver nanoparticles and swelling ratio. The electrical conductivity of the nanocomposite hydrogel was studied and it was found to be affected by the swelling ratio of the hydrogel as well as its content of silver nanoparticles. PMID:24928058

Abdel-Halim, E S; Al-Deyab, Salem S

2014-08-01

303

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

PubMed

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

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

2015-02-01

304

Long-term effect of xylitol gum use on mutans streptococci in adults.  

PubMed

Many studies have shown the effects of chewing xylitol gum on mutans streptococci (MS) over short- and long-term periods in children; however, few studies have addressed long-term periods in adults. The objective of this investigation was to examine for 6 months the effects of chewing xylitol gum on MS in saliva and plaque in 127 adults (mean age 28.0 years). The participants were assigned to three groups according to gum type, in part taking preference for flavor into account and in part at random: xylitol (XYL), maltitol (MAL) and control (CR); 33, 34 and 27 subjects in each group, respectively, completed the trial. Daily gum use of the XYL and MAL groups was 7.9 and 7.1 g, respectively. MS levels, which declined significantly in saliva (p < 0.05) and plaque (p < 0.001) in the XYL group after 6 months, exhibited a significant increase in plaque in the MAL group (p < 0.001). Differences in relative changes of MS levels in plaque during the experimental period were significant between the XYL group and the CR (p < 0.05) and MAL groups (p < 0.001). Differences in relative change of amount of plaque during the experimental period were not statistically significant between the groups. The present study demonstrated that chewing xylitol gum for 6 months continued to inhibit the growth of mutans streptococci in adults. PMID:17426399

Haresaku, S; Hanioka, T; Tsutsui, A; Yamamoto, M; Chou, T; Gunjishima, Y

2007-01-01

305

Cigarette smoking and nicotine gum (0, 2 and 4 mg): effects upon four visual attention tasks.  

PubMed

Sixteen regular smokers, abstinent for 12 h prior to testing, were assessed on a battery of four visual attention tasks: rapid visual information processing (RVIP), letter cancellation, Stroop, and width of attention. Each subject was assessed under four conditions: placebo gum, 2 mg nicotine gum, 4 mg nicotine gum, and cigarette smoking (own brand), with the order of drug administration determined by latin square. Pre-post drug difference scores for letter cancellation response time demonstrated a significant monotonic dose-response function, with significantly faster performance following cigarette than placebo. RVIP response time and target detection were also affected by nicotine. One RVIP task parameter demonstrated a significant monotonic dose-response function, with highest performance under smoking. Other RVIP measures demonstrated curvilinear dose-response functions, with highest performance under nicotine gum, and broadly similar performance after placebo gum and cigarette smoking. Monotonic and inverted-U arousal/performance functions similar to these have been demonstrated in previous research with nicotine. In contrast to the significant changes in sustained attention, neither width of attention nor Stroop task performance (an index of distractability) was affected by nicotine. Resting heart rate and subjective 'need for a cigarette' showed the predicted monotonic dose-response functions following nicotine. There were no significant changes in any Profile of Mood State factor. PMID:1603292

Parrott, A C; Craig, D

1992-01-01

306

Adsorption of guar gum onto quartz from dilute mixed electrolyte solutions.  

PubMed

The effect of potassium, sodium, calcium, magnesium, and hydrogen cations on adsorption of guar gum onto quartz was investigated at natural pH. The role of the background ions was analyzed in terms of their water-structure making or breaking capabilities. In dilute solutions (0.01 mol/L) of structure-makers (NaCl, HCl, CaCl2, and MgCl2), the guar gum adsorption density did not change compared to the adsorption densities obtained in distilled water. Potassium, the only structure-breaking ion (chaotrope) among the tested cations, significantly enhanced guar gum adsorption. The results obtained in mixed electrolytes demonstrate that the strong structure-breaking properties of K+ overcome any contributions from weak structure making ions (kosmotropes), and guar gum adsorption remains at the levels observed in KCl alone. Only when strongly hydrated Mg2+ ions are mixed with KCl, the overall effect becomes additive and the influence of potassium is proportionally reduced by increasing concentrations of magnesium cations. In this approach, guar gum adsorption on quartz is viewed as a competition between polysaccharide and water molecules for silanol surface sites. The hydration of the quartz surface inhibits the adsorption process but the competition equilibrium, and hence polysaccharide adsorption, can be affected by the presence of chaotropes or kosmotropes. PMID:16443235

Ma, Xiaodong; Pawlik, Marek

2006-06-15

307

Utilizing guar gum for development of "tabs in cap' system of losartan potassium for chronotherapeutics.  

PubMed

The project was aimed to achieve biphasic pulsed drug release of losartan potassium by fabricating 'Tabs in cap' system wherein drug loaded tablets sandwiched the erodible guar gum time spacer tablet. The system was capsulated in non biodegradable body capped with water soluble cap. The system was investigated for in-vitro release and ex-vivo continuous dissolution-absorption and stability. The influence of spray dried lactose (SDL): guar gum ratio on lag time was investigated. In-vitro release capsule evidenced immediate release followed by delayed pulse (>90%) and a lag time 6h was achieved by maintaining an optimum ratio of SDL: guar gum in erodible guar gum tablet. Ex-vivo continuous dissolution-absorption study demonstrated two successive pulses for dissolution and indicated delay in absorption of drug. Histological study revealed viability of intestinal cells and the system had shelf- life of 15 months. Conclusively, using guar gum spacer tablet, biphasic pulsed drug release 'Tabs in Cap' system of losartan potassium was successfully developed that has potential for chronotherapeutics in hypertension. PMID:25268456

Gangwar, Guarav; Kumar, Anil; Pathak, Kamla

2015-01-01

308

Mechanical and barrier properties of guar gum based nano-composite films.  

PubMed

Guar gum based nano-composite films were prepared using organically modified (cloisite 20A) and unmodified (nanofil 116) nanoclays. Effect of nanoclay incorporation on mechanical strength, water vapor barrier property, chromatic characteristics and opacity of films was evaluated. Nano-composites were characterized using X-ray scattering, FTIR and scanning electron microscopy. A nanoclay concentration dependent increase in mechanical strength and reduction in water vapor transmission rate was observed. Films containing nanofil 116 (2.5% w/w guar gum) and closite 20A (10% w/w guar gum) demonstrated a 102% and 41% higher tensile strength, respectively, as compared to the control. Lower tensile strength of cloisite 20A films as compared to nanofil 116 films was due to its incompatibility with guar gum. X-ray scattering analysis revealed that interstitial spacing between nanofil 116 and cloisite 20A sheets increased due to intercalation by guar gum polymer. This resulted in improved mechanical and barrier properties of nano-composites compared to control. PMID:25839796

Saurabh, Chaturbhuj K; Gupta, Sumit; Bahadur, Jitendra; Mazumder, S; Variyar, Prasad S; Sharma, Arun

2015-06-25

309

Magnetism  

NSDL National Science Digital Library

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.

David Stern

310

Changes in electrical energy requirements to operate an ice cream freezer as a function of sweeteners and gums  

Microsoft Academic Search

Changes in electrical energy required to operate a continuous freezer were monitored for various ice cream formulae. Ice cream formulae consisted of nine different combinations of sucrose, 36 DE corn syrup, and 42 high fructose corn syrup as well as two ratios of guar gum to locust bean gum. Within the same sweetening system, a mix high in locust bean

D. E. Smith; A. S. Bakshi; S. A. Gay

1985-01-01

311

Mapping Land Use Land Cover Using NDVI in a Semi-arid Areas in Gum Arabic Belt, Sudan  

Microsoft Academic Search

Gum arabic belt is most important region in Sudan with producing gum arabic in global level. Each land cover type has different spectral characteristics, absorbing some frequencies of light and reflecting others. With an understanding of the reflectance characteristics and some ground observations, it is possible to use remotely sensed data to make inferences about the type of land cover

Hassan Elnour Adam; Elmar Csaplovics

2010-01-01

312

Formulation of Extruded Snack Food (Gum Based Cereal–Pulse Blend): Optimization of Ingredients Levels Using Response Surface Methodology  

Microsoft Academic Search

Response surface methodology (RSM) was used to analyse the effect of corn flour, green gram flour, xanthan, guar gum, arabic gum and carboxymethyl cellulose (CMC) on the sensory and objective (expansion ratio) attributes of an extruded snack food. A rotatable central-composite design was used to develop models for the sensory and objective responses. The experiments were run at 160°C with

Sushma Thakur; D. C Saxena

2000-01-01

313

Preparation and in vitro evaluation of guar gum based triple-layer matrix tablet of diclofenac sodium  

PubMed Central

The objective of the present study was to design an oral controlled drug delivery system for sparingly soluble diclofenac sodium (DCL) using guar gum as triple-layer matrix tablets. Matrix tablet granules containing 30% (D1), 40% (D2) or 50% (D3) of guar gum were prepared by the conventional wet granulation technique. Matrix tablets of diclofenac sodium were prepared by compressing three layers one by one. Centre layer of sandwich like structure was incorporated with matrix granules containing DCL which was covered on either side by guar gum granule layers containing either 70, 80 or 87% of guar gum as release retardant layers. The tablets were evaluated for hardness, thickness, drug content, and drug release studies. To ascertain the kinetics of drug release, the dissolution profiles were fitted to various mathematical models. The in vitro drug release from proposed system was best explained by the Hopfenberg model indicating that the release of drug from tablets displayed heterogeneous erosion. D3G3, containing 87% of guar gum in guar gum layers and 50% of guar gum in DCL matrix granule layer was found to provide the release rate for prolonged period of time. The results clearly indicate that guar gum could be a potential hydrophilic carrier in the development of oral controlled drug delivery systems. PMID:23181081

Chavda, H.V.; Patel, M.S.; Patel, C.N.

2012-01-01

314

Enzymatic production and characterization of manno-oligosaccharides from Gleditsia sinensis galactomannan gum.  

PubMed

Enzymatic hydrolysis of Gleditsia sinensis gum was performed to produce manno-oligosaccharides having functional applications as dietary fiber and prebiotics. The optimum hydrolysis conditions, including enzyme loading, temperature and time, from response surface methodology were 8.1 U/g, 57.4 °C and 34.1 h, respectively. The yield of DP 1-5 oligosaccharides was 75.9% (29.1 g/L). The Michaelis-Menten kinetics and molecular weight distribution were determined. The obtained oligosaccharides were further separated by HPLC and SEC, and the galactose distribution of G. sinensis gum was elucidated. Results indicated that G. sinensis gum has potential to produce value-added oligosaccharides in food industries. PMID:23357797

Jian, Hong-Lei; Zhu, Li-Wei; Zhang, Wei-Ming; Sun, Da-Feng; Jiang, Jian-Xin

2013-04-01

315

Role of viscous guar gums in lowering the glycemic response after a solid meal.  

PubMed

The aim of the present study was to investigate how guar gum viscosity acts on starch digestion and glucose absorption in humans. Six healthy subjects received a mixed diet composed of 60.4% carbohydrate in the form of maize glucose or pregelatinized starch, to which was added 5.6% low- or high-viscosity guar gums. Meals were ingested or instilled in the duodenum and postprandial insulin and glucose responses were monitored for 3 h. Infusion of meals containing glucose showed that the delay in the diffusion rate to the duodenal mucosa due to bolus viscosity was not significant. Infusion of meals containing starch showed that a decrease in the digestion rate of starch in the upper small intestine accounted for part of the effect of viscosity on glycemic response, whereas the main effect of guar gum was apparently to slow gastric emptying. PMID:7818627

Leclère, C J; Champ, M; Boillot, J; Guille, G; Lecannu, G; Molis, C; Bornet, F; Krempf, M; Delort-Laval, J; Galmiche, J P

1994-04-01

316

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

PubMed Central

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

2012-01-01

317

Nasal administration of ondansetron using a novel microspheres delivery system.  

PubMed

Gellan gum microspheres of ondansetron hydrochloride, for intranasal delivery, were prepared to avoid the first pass metabolism as an alternative therapy to parentral, and to improve therapeutic efficiency in treatment of nausea and vomiting. The microspheres were prepared using conventional spray-drying method. The microspheres were evaluated for characteristics like particle size, incorporation efficiency, swelling ability, zeta potential, in-vitro mucoadhesion, thermal analysis, XRD study and in-vitro drug release. Treatment of in-vitro data to different kinetic equations indicated diffusion controlled drug delivery from gellan gum microspheres. The results of DSC and XRD studies revealed molecular amorphous dispersion of ondansetron into the gellan gum microspheres. PMID:19519195

Mahajan, Hitendra S; Gattani, Surendra G

2009-01-01

318

Design of sterculia gum based double potential antidiarrheal drug delivery system.  

PubMed

In view of the antidiarrheal properties of sterculia gum and ornidazole, an attempt has been made to synthesize novel hydrogels by functionalization of sterculia gum with poly(vinylpyrrolidone) (PVP) for release of the model antidiarrheal drug ornidazole. These hydrogels were characterized with FTIR, SEM, TGA and swelling behavior. Swelling kinetics of the hydrogels and in vitro release dynamics of ornidazole from the drug loaded hydrogels have been studied to determine the mechanism of swelling and drug release from the drug loaded hydrogels. A Fickian diffusion mechanism has been observed for the release of drug from the hydrogels. These hydrogels may have dual actions for the treatment of diarrhea. PMID:20889316

Singh, Baljit; Sharma, Nisha

2011-02-01

319

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

NASA Astrophysics Data System (ADS)

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.

Withey, Elizabeth Ann

320

Effects of Three Mastic Gums on the Number of Mutans Streptococci, Lactobacilli and PH of the Saliva  

PubMed Central

Objective: In the recent years, herbal oral hygiene products have gained increasing attention. The aim of this study was to assess the effects of three types of mastic gums on the level of Mutans streptococci, Lactobacilli and pH of the saliva. Materials and Methods: Forty-two students in the age range of 20–30 years were divided into three parallel groups; each of them separately used pure mastic gum, xylitol mastic gum and probiotic mastic gum for three weeks. Number of microorganisms and pH of the saliva were assessed before and after the intervention. The data were analyzed using Wilcoxon Signed Rank, paired-sample-t, Kruskal-Wallis and Tukey’s post-hoc tests and Oneway ANOVA. Results: Level of Mutans streptococci showed a significant reduction compared to its baseline value in all three groups (P<0001 for all). Salivary Lactobacillus count increased in the groups using pure and xylitol mastic gums but decreased in the group using probiotic type, albeit these changes were only significant in the group using probiotic mastic gum (P<0.001). Use of pure and xylitol mastic gums increased the pH of the saliva but not significantly. In the group using probiotic mastic gum, the pH of the saliva decreased significantly (P=0.029). Conclusion: Three weeks use of all mastic gums resulted in a significant drop in the number of Mutans streptococci in the saliva. However, the drop in the saliva pH due to the use of probiotic mastic gum is not in favor of dental health. PMID:25628697

Biria, Mina; Eslami, Gita; Taghipour, Elaheh; Akbarzadeh Baghban, Alireza

2014-01-01

321

Partially hydrolyzed guar gum in pediatric functional abdominal pain  

PubMed Central

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

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

2013-01-01

322

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

PubMed

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

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

2014-10-01

323

Effectiveness of almond gum trees exudate as a novel edible coating for improving postharvest quality of tomato (Solanum lycopersicum L.) fruits.  

PubMed

The use of coatings is a technique used to increase postharvest life of the fruit. Almond gum exudate was used, in comparison with gum arabic, at concentrations of 10% as a novel edible coating, to preserve the quality parameters of tomato (Solanumlycopersicum). Fruits were harvested at the mature-green stage of ripening. Results showed that the coatings delayed significantly (p?gum and gum arabic coatings to maintain the overall quality of tomato fruits during storage period (20 days). In addition, the difference between gum arabic and almond gum coatings was not significant (p?>?0.05) except for pulp color. Therefore, we can suggest the use of almond gum exudate as a novel edible coating extends the shelf-life of tomato fruits on postharvest. PMID:23733822

Mahfoudhi, Nesrine; Chouaibi, Moncef; Hamdi, Salem

2014-01-01

324

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 ...

325

Corn fiber gum: New structure/function relationships for this potential beverage flavor stabilizer  

Technology Transfer Automated Retrieval System (TEKTRAN)

Corn fiber arabinoxylan is a hemicellulose B isolated from the fibrous portions (pericarp, tip cap, and endosperm cell wall fractions) of corn kernels by alkaline solution, often in the presence of hydrogen peroxide and is commonly referred to as “Corn fiber gum” (CFG). The unique polysaccharide, C...

326

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

PubMed

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

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

2013-10-01

327

Stability and thermal conductivity enhancement of carbon nanotube nanofluid using gum arabic  

Microsoft Academic Search

This experimental study reports on the stability and thermal conductivity enhancement of carbon nanotubes (CNTs) nanofluids with and without gum arabic (GA). The stability of CNT in the presence of GA dispersant in water is systematically investigated by taking into account the combined effect of various parameters, such as sonication time, temperature, dispersant and particle concentration. The concentrations of CNT

W. Rashmi; A. F. Ismail; I. Sopyan; A. T. Jameel; F. Yusof; M. Khalid; N. M. Mubarak

2011-01-01

328

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...

329

Structure and properties of the gummed paper for removable fired decals  

Microsoft Academic Search

Gummed paper is a component part of commerical decals and is intended to fulfill certain technological functions at the preparation stage of the decal itself and in the decoration of the article. The current idea that these functions are completed at the operation when the removable decal is stripped off does not correspond to what actually happens. The results we

A. I. Golubev; I. P. Tuzova

1986-01-01

330

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

ERIC Educational Resources Information Center

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…

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

2008-01-01

331

Hydroperiod Influence on Breakdown of Leaf Litter in Cypress-gum Wetlands  

Microsoft Academic Search

Many cypress-gum wetlands in the southeast United States are isolated from rivers and streams and are seasonally inundated by rainfall. Organic matter processing in these wetlands is caused primarily by biotic components (i.e., microbes and invertebrates), which are influenced by timing and duration of seasonal inundation, and low dissolved ox- ygen levels. Using litter bags, we examined breakdown of cypress

JULIANN M. BATTLE; STEPHEN W. GOLLADAY

2001-01-01

332

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

Technology Transfer Automated Retrieval System (TEKTRAN)

Biopolymers derived from renewable resources are an emerging class of advanced materials that offer many useful properties for a wide range of food and non-food applications. Current state of the art in research and development of renewable polymers as adhesives, gums, binders and emulsions will be ...

333

Stuck on You: Chewing Gum Adherent to the Oral Airway in Electroconvulsive Therapy (ECT).  

PubMed

We present a case in which a piece of chewing gum was discovered adhering to the oral airway when it was removed after an ECT procedure. We suggest that careful examination of the patient's mouth for foreign objects be a standard part of the pre-ECT protocol. PMID:25268044

Kellner, Charles H; Bryson, Ethan O; Aloysi, Amy S; Pasculli, Rosa M; Briggs, Mimi C

2014-09-29

334

Chitosan/pectin/gum Arabic polyelectrolyte complex: process-dependent appearance, microstructure analysis and its application.  

PubMed

Novel chitosan/pectin/gum Arabic polyelectrolyte complex (PEC) solutions and membranes with various compositions were prepared for biomedical applications. The appearance of the PEC solutions, either clear or turbid, was process-dependent and depended on how the three components were dissolved and mixed. The addition of gum Arabic to the chitosan and pectin significantly decreased the viscosities of the resultant PEC solutions due to the formation of globe-like microstructures that was accompanied by network-like microstructures and other molecular entanglements. The mechanical strength and hydrophilicity of the PEC membranes manufactured from the PEC solutions, especially for a weight ratio of 84/8/8 (chitosan/pectin/gum Arabic), were enhanced compared to pure chitosan membranes. Moreover, the use of the 84/8/8 PEC membranes as a drug carrier exhibited steady and fairly complete release of a drug (insulin) for 6h. Based on these promising results, the chitosan/pectin/gum Arabic PEC membranes have great potential in controlled drug release applications. PMID:24299835

Tsai, Ruei-Yi; Chen, Pin-Wen; Kuo, Ting-Yun; Lin, Che-Min; Wang, Da-Ming; Hsien, Tzu-Yang; Hsieh, Hsyue-Jen

2014-01-30

335

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Determination of Sales at Less Than Fair Value and Postponement of Final Determination...concerning, Less Than Fair Value Investigation of Xanthan Gum...second with a trisaccharide side chain consisting of P-D-Mannose...estimated amount by which the normal value exceeds the U.S. price...

2013-06-04

336

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

Microsoft Academic Search

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

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

1997-01-01

337

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

PubMed Central

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

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

2011-01-01

338

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

Microsoft Academic Search

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

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

2012-01-01

339

Preparation and characterization of cross-linked guar gum microspheres: optimization using factorial design.  

PubMed

In the present work cross-linked guar gum microspheres were prepared for colon specific delivery of ornidazole. Development and optimization of guar gum microspheres for colonic drug delivery was carried out using a 2(4) factorial design based on four independent variables. Microspheres were prepared by emulsification method using glutaraldehyde as cross-linking agent. Morphology and surface characteristics of the formulations were determined by scanning electron microscopy. Particle size of the guar gum microspheres was determined by particle size analyzer. In vitro drug-release studies were performed in conditions simulating stomach-to-colon transit in the presence and absence of rat cecal contents. Only a small fraction of drug was released at acidic pH; however, the release of drug was found to be higher in the presence of rat cecal contents, indicating the susceptibility of guar gum matrix to colonic enzymes released from rat cecal contents. The significance of differences was evaluated by analysis of variance (ANOVA). Differences were considered statistically significant at p<0.05. PMID:21297297

Kumar, Shukla Raj; Piyush, Trivedi; Suman, Ramteke; Akanksha, Tiwari

2011-01-01

340

The development of a new corn fiber gum isolation process that preserves 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...

341

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

ERIC Educational Resources Information Center

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…

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

2010-01-01

342

Effects of caffeine chewing gum on race performance and physiology in male and female cyclists.  

PubMed

This investigation reports the effects of chewing caffeinated gum on race performance with trained cyclists. Twenty competitive cyclists completed two 30-km time trials that included a maximal effort 0.2-km sprint each 10-km. Caffeine (~3-4 mg · kg(-1)) or placebo was administered double-blind via chewing gum at the 10-km point following completion of the first sprint. Measures of power output, oxygen uptake, heart rate, lactate and perceived exertion were taken at set intervals during the time trial. Results indicated no substantial differences in any measured variables between caffeine and placebo conditions during the first 20-km of the time trial. Caffeine gum did however lead to substantial enhancements (mean ± 90% confidence limits (CLs)) in mean power during the final 10-km (3.8% ± 2.3%), and sprint power at 30-km (4.0% ± 3.6%). The increases in performance over the final 10-km were associated with small increases in heart rate and blood lactate (effect size of 0.24 and 0.28, respectively). There were large inter-individual variations in the response to caffeine, and apparent gender related differences in sprint performance. Chewing caffeine gum improves mean and sprint performance power in the final 10-km of a 30-km time trial in male and female cyclists most likely through an increase in nervous system activation. PMID:25517202

Paton, Carl; Costa, Vitor; Guglielmo, Luiz

2015-05-01

343

Isolation, purification and identification of protein associated with corn fiber gum  

Technology Transfer Automated Retrieval System (TEKTRAN)

Corn fiber gum (CFG), an alkaline hydrogen peroxide extract of corn kernel milling by-product “corn fiber” is a proteinaceous arabinoxylan with a protein content ranging from ca. 2 to 9% by weight for the CFG samples isolated from different corn milling fiber sources. Several studies have suggested...

344

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...

345

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

PubMed Central

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

Bontha, Vijaya Kumar

2013-01-01

346

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%, ...

347

The effect of sugar-free and sugar chewing gums on plaque deposition  

PubMed Central

Background: Chewing gum is a habit practiced regularly by a relatively high proportion of individuals in many countries including India, and its use has increased within the last decade. The aim of this study was to determine the effects of sugar-free and sugar chewing gums on plaque deposition. Materials and Methods: The study is a double blind clinical trial involving 16 healthy volunteers (divided into 2 groups) in a 4-day plaque regrowth model. On day one, subjects received professional prophylaxis, suspended oral hygiene measures, and commenced chewing their allocated product. Gum chewing was one piece chewed for 30 minutes 3 times a day. On day 5, subjects were scored for plaque with the help of Silness and Loe Index. Results: Results show sugar-free group have a lesser mean plaque score of 0.98 as compare to sugar group (1.23), though this difference was not statistically significant. Conclusion: The sugar-free gums can be used as an adjunct to mechanical oral hygiene measures. PMID:23087737

Tangade, Pradeep; Mathur, Anmol; Chaudhary, Shikha; Gupta, Rahul

2012-01-01

348

Novel etherified locust bean gum-alginate hydrogels for controlled release of glipizide  

Microsoft Academic Search

On many occasions, homopolysaccharide hydrogel networks alone are not suitable for controlled drug delivery. In this study, interpenetrating networks (IPNs) of sodium alginate (ALG) and etherified locust bean gum (ELBG) were developed through ionotropic gelation with Al ions, tested for glipizide release, and were compared with homopolymer hydrogel networks. The degree of reticulation in IPNs was explained by the neutralization

Paramita Dey; Sabyasachi Maiti; Biswanath Sa

2012-01-01

349

Peroxidase mediated conjugation of corn fibeer gum and bovine serum albumin to improve emulsifying properties  

Technology Transfer Automated Retrieval System (TEKTRAN)

The emulsifying properties of corn fiber gum (CFG), a naturally-occurring polysaccharide protein complex, were improved by kinetically controlled formation of hetero-covalent linkages with bovine serum albumin (BSA), using horseradish peroxidase. The formation of hetero-crosslinked CFG-BSA conjugate...

350

Kinetic release studies of nitrogen-containing bisphosphonate from gum acacia crosslinked hydrogels.  

PubMed

Natural polymer hydrogels are useful for controlling release of drugs. In this study, hydrogels containing gum acacia were synthesized by free-radical polymerization of acrylamide with gum acacia. The effect of gum acacia in the hydrogels on the release mechanism of nitrogen-containing bisphosphonate (BP) was studied at pH 1.2 and 7.4. The hydrogels exhibited high swelling ratios at pH 7.4 and low swelling ratios at pH 1.2. The release study was performed using UV-Visible spectroscopy via complex formation with Fe(III) ions. At pH 1.2, the release profile was found to be anomalous while at pH 7.4, the release kinetic of BP was a perfect zero-order release mechanism. The hydrogels were found to be pH-sensitive and the release profiles of the BP were found to be influenced by the degree of crosslinking of the hydrogel network with gum acacia. The preliminary results suggest that these hydrogels are promising devices for controlled delivery of bisphosphonate to the gastrointestinal region. PMID:25445681

Aderibigbe, B A; Varaprasad, K; Sadiku, E R; Ray, S S; Mbianda, X Y; Fotsing, M C; Owonubi, S J; Agwuncha, S C

2015-02-01

351

Colon targeted guar gum compression coated tablets of flurbiprofen: formulation, development, and pharmacokinetics.  

PubMed

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 C(max) of colon targeted tablets was 11956.15?ng/mL at T max 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

Vemula, Sateesh Kumar; Bontha, Vijaya Kumar

2013-01-01

352

Synthesis of galactosyl glycerol from guar gum by transglycosylation of ?-galactosidase from Aspergillus sp. MK14.  

PubMed

A guar gum-hydrolyzing strain, Aspergillus sp. MK14, secreted ?-galactosidase selectively in liquid culture. Its ?-galactosidase activity (0.820 U/ml) was much higher than its ?-mannosidase and ?-mannanase activities (0.027 and 0.050 U/ml, respectively). The molecular weight was estimated to be 59,000 Da by SDS-PAGE. The optimal pH was 5 and it was active from pH 2.2 to 6.2. The optimal temperature was 60 °C and the activity was stable below 50 °C. Enzyme activity toward melibiose was much lower than that with pNP-?-D-galactopyranoside. The activities toward 6(1)-?-D-galactosyl-mannobiose and 6(3),6(4)-?-D-galactosyl-mannopentaose were relatively high (86.2% and 48.4% relative to pNP-?-D-galactopyranoside, respectively). MK14 crude enzyme released only the monosaccharides, galactose and mannose (Gal/Man: 0.64) from guar gum. When glycerol was added to the reaction mixture, the transglycosylation proceeded efficiently, and the synthesis of galactosyl glycerol was 76.6 mg/g of guar gum. MK14 ?-galactosidase could use guar gum as a good substrate (donor) in the transglycosylation. PMID:25442536

Kurakake, Masahiro; Okumura, Takumi; Morimoto, Youichirou

2015-04-01

353

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

PubMed Central

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

Kumar, M. Uday; Babu, M. Kishore

2014-01-01

354

Effects of high-hydrostatic pressure and pH treatments on the emulsification properties of gum arabic.  

PubMed

This study investigated the emulsification properties of the native gums and those treated at high pressure (800MPa) both at their "natural" pH (4.49 and 4.58, respectively) and under "acidic and basic" pH (2.8 and 8.0) conditions. The emulsification behaviour of KLTA gum was found to be superior to that of the GCA gum. High pressure and pH treatment changed the emulsification properties of both gums. The acidic amino acids in gum arabic were shown to play an important role in their emulsification behaviour, and mechanisms of emulsification for the two gums were suggested to be different. The highly "branched" nature of the carbohydrate in GCA gum was also thought to be responsible for the "spreading" of droplet size distributions observed. Coomassie brilliant blue binding was used to indicate conformational changes in protein structure and Ellman's assay was used to estimate any changes in levels of free thiols present. PMID:25872433

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

2015-10-01

355

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

PubMed

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

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

2014-01-01

356

The Use of Hibiscus esculentus (Okra) Gum in Sustaining the Release of Propranolol Hydrochloride in a Solid Oral Dosage Form  

PubMed Central

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

Noordin, Mohamed Ibrahim; Kadivar, Ali

2014-01-01

357

Effect of organic matter on estuarine flocculation: a laboratory study using montmorillonite, humic acid, xanthan gum, guar gum and natural estuarine flocs  

PubMed Central

Background Riverine particles undergo a rapid transformation when they reach estuaries. The rapid succession of hydrodynamic and biogeochemical regimes forces the particles to flocculate, settle and enter the sediment pool. The rates and magnitudes of flocculation depend on the nature of the particles which are primarily affected by the types and quantities of organic matter (OM). Meanwhile, the OM characteristics vary widely between environments, as well as within a single environment due to seasonal climate and land use variability. We investigated the effect of the OM types and quantities through laboratory experiments using natural estuarine particles from the Mississippi Sound and Atchafalaya Bay as well as model mixtures of montmorillonite and organic molecules (i.e., biopolymers (guar/xanthan gums) and humic acid). Results Biopolymers promote flocculation but the magnitude depends on the types and quantities. Nonionic guar gum yields much larger flocs than anionic xanthan gum, while both of them exhibit a nonlinear behavior in which the flocculation is the most pronounced at the intermediate OM loading. Moreover, the effect of guar gum is independent of salinity whereas the effect of xanthan gum is pronounced at higher salinity. Meanwhile, humic acid does not affect flocculation at all salinity values tested in this study. These results are echoed in the laboratory manipulation of the natural estuarine particles. Flocculation of the humic acid-rich Mississippi Sound particles is unaffected by the OM, whereas that of biopolymer-rich Atchafalaya Bay particles is enhanced by the OM. Conclusions Flocculation is positively influenced by the presence of biopolymers that are produced as the result of marine primary production. Meanwhile, humic acid, which is abundant in the rivers that drain the agricultural soils of Southeastern United States, has little influence on flocculation. Thus, it is expected that humic acid-poor riverine particles (e.g., Mississippi River, and Atchafalaya River, to a lesser degree) may be prone to rapid flocculation and settling in the immediate vicinity of the river mouths when mixed with biopolymer-rich coastal waters. It is also expected that humic acid-rich riverine particles (e.g., Pearl River) may resist immediate flocculation and be transported further away from the river mouth. PMID:24386944

2014-01-01

358

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

PubMed Central

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

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

2007-01-01

359

In Vivo Efficacy of Gum Obtained Pistacia Atlantica in Experimental Treatment of Cutaneous Leishmaniasis  

PubMed Central

Background: Recent circumstantial evidences are suggesting that an increasing number of Iranian patients with cutaneous leishmaniasis are unresponsive to meglumine antimoniate (Glucantime®). Pistacia atlantica is native plant in Iran (central, western, and eastern regions). Gum obtained Pistacia atlantica has been reported to possess considerable in vitro antimicrobial activity. In this study, we aimed to investigate antileishmanial activity of P. atlantica. Methods Male BALB/c mice were inoculated subcutaneously 2×106 L. major Promastigotes (MHROM/IR/75/ER) at the base of tail in 2007. Mice were randomly divided into 3 groups. in group 1 Glucantime® was administered to the BALB/c mice in regimen of 60 mg per kg of body weight for 28 days by intraperitoneal injections per day, in group 2 the gum of P. atlantica var. Kurdica were tested by rubbing of local lesions for 28 days, group 3 infected but non-treated. Comparisons of treated groups and untreated group were done by two-way analysis of variance (ANOVA) Results Topically rubbing administration of gum obtained P. atlantica var. kurdica daily for 28 days like Glucantime® decreased skin lesion size in the BALB/c mice infected with L. major compared with that in the control (P< 0.01). Treatment BALB/c mice with gum obtained P. atlantica var. kurdica and Glucantime® causes decrease number of parasitologicaly positive mice (P< 0.05). Conclusion Our results show that gum obtained P. atlantica var. kurdica can be used for controlling cutaneous leishmaniasis caused by L. major and inhibiting development of cutaneous leishmaniasis lesions. PMID:23112988

Taran, M; Mohebali, M; Esmaeli, J

2010-01-01

360

Comparison of soybean oils, gum, and defatted soy flour extract in stabilizing menhaden oil during heating.  

PubMed

Capabilities of crude soy oil, degummed oil, gum, and defatted soy flour extract in preventing the oxidation of menhaden oil and its omega-3 fatty acids, DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid), during heating were evaluated. The menhaden oil mixed with defatted soy flour extract demonstrated the greatest stability by producing the lowest TBA reactive oxidation products and retaining the highest concentrations of DHA and EPA after heating at 150 degrees C for 30 min. A range of 62.8% to 71.5% of DHA and 67.7% to 75.9% of EPA remained in the fish oil with defatted soy flour extract, while only 29.9% of DHA and 37.2% of EPA were retained in the fish oil with no addition. Stabilizing capability from highest to lowest was defatted flour extract > gum > degummed oil = crude oil. The defatted flour extract had the highest level of total phenolic content (11.3 microg catechin equivalent/g), while crude oil, degummed oil, and gum contained 7.1, 6.1, and 6.0 microg catechin equivalent/g, respectively. The level of isoflavones in the defatted soy flour extract was 55 mg/g, which was over 100 times higher than in the crude oil or gum. Although isoflavones were not detected in the degummed oil, it contained the highest level of tocopherols (414 mug/g), whereas the lowest level (215 microg/g) was found in the defatted flour extract. The order of free radical scavenging capability measured from high to low was the defatted soy flour extract, crude oil, degummed oil, and gum. PMID:18211344

Yue, X; Xu, Z; Prinyawiwatkul, W; Losso, J N; King, J M; Godber, J S

2008-01-01

361

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

PubMed

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

Ragothaman, Murali; Palanisamy, Thanikaivelan; Kalirajan, Cheirmadurai

2014-12-19

362

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

...Petitioner converted ethanol (ethyl alcohol) from liters to kilograms because the Thai surrogate value...including, but not limited to, solutions, slurries, dry powders of any particle size, or unground fiber. Xanthan gum...

2012-07-02

363

Hydrogen peroxide (H?O?) supply significantly improves xanthan gum production mediated by Xanthomonas campestris in vitro.  

PubMed

To improve xanthan gum productivity, a strategy of adding hydrogen peroxide (H?O?) was studied. The method could intensify oxygen supply through degradation of H?O? to oxygen (O?). In shake flask testing, the xanthan gum yield reached 2.8% (improved by 39.4%) when adding 12.5 mM H?O? after 24 h of fermentation. In fermentor testing, it was obvious that the oxygen conditions varied with the H?O? addition time. Eventually, gum yield of 4.2% (w/w) was achieved (increased by 27.3%). Compared with the method of intense mixing and increasing the air flow rate, adding H?O? to improve the dissolved oxygen concentration was more effective and much better. Moreover, addition of H?O? improved the quality of xanthan gum; the pyruvate content of xanthan was 4.4% (w/w), higher than that of the control (3.2%). PMID:22183692

Cheng, Rong; Lin, Lin; Zhang, Yongkui

2012-05-01

364

Comparisons of 13 edible gum-hydrate fat substitutes for low fat Kung-wan (an emulsified meatball)  

Microsoft Academic Search

In this study, we used edible gum-hydrates to replace pork fat in developing low fat Kung-wan, an emulsified meatball. A one-way completely randomized design was adopted for comparing three controls and 13 edible gum-hydrates as fat substitutes. Results indicated that replacing fat with water caused lower cooking yield, smaller diameter, inferior sensory qualities and lower texture profile analysis indices. Eight

S. Y. Hsu; H.-Y. Chung

1999-01-01

365

Estimates of fallout from Nevada weapons testing in the western United States based on gummed-film monitoring data  

Microsoft Academic Search

Estimates of ¹³⁷Cs depositions from Nevada atmospheric nuclear weapons testing at the Nevada Test Site are presented for 25 sites in Nevada, Utah, California, Arizona, New Mexico, Idaho, Colorado, and Wyoming. These estimates are based primarily on a reappraisal of total beta deposition measured with gummed-film directly after the tests. Maps of the estimated ¹³⁷Cs deposition at the gummed-film and

Beck

1984-01-01

366

Effect of gum tragacanth exuded by three Iranian Astragalus on mixed milk protein system during acid gelation.  

PubMed

The effects of various concentrations of three species of gum tragacanth on the gelation process, microstructure and viscoelastic properties of milk protein mixed gels acidified at 37°C by glucono-?-lactone (GDL) were investigated using dynamic rheometry and microscopy. According to rheological measurements, the addition of gum tragacanth in the range of 0.05-0.2% (w/w) into milk protein dispersions led to a weaker structure for the milk protein network, compared to the control sample. This weakening effect could be eliminated by adding 0.3% (w/w) gum tragacanth exudates from A. gossypinus; the compositional features of gum tragacanth may have been responsible for the improved protein-protein interactions, greater structural strength and reduced gelation time onset. It was determined by scanning electron microscopy that the addition of gum tragacanth at a low concentration caused the density of the matrix to increase, while an open structure was observed in the presence of a higher gum concentration. PMID:23146825

Nejatian, Mohammad; Hatami, Masoud; Mohammadifar, Mohammad Amin

2013-02-01

367

Oral adverse reactions due to cinnamon-flavoured chewing gums consumption.  

PubMed

Cinnamon-flavoured products (toothpaste, chewing gum, food, candy and mouthwash) can cause oral adverse reactions; among these, the most common is contact stomatitis (cinnamon contact stomatitis, CCS). Signs and symptoms of contact allergic reactions affecting the oral mucosa can mimic other common oral disorders, making diagnosis difficult. As CCS may be more prevalent than believed and its clinical features can frequently determine misdiagnosis, we reviewed case reports and case series of oral adverse reactions due to cinnamon-containing chewing gums, emphasizing clinical aspects, diagnostic and management procedures. We also proposed an algorithm to perform a diagnosis of CCS as in the previous published literature the diagnostic approach was not based on a harmonized and shared evidence-based procedure. Moreover, as patients can refer to different specialists as dentists, dermatologists and allergists, a multidisciplinary approach is suggested. PMID:24004186

Calapai, G; Miroddi, M; Mannucci, C; Minciullo, Pl; Gangemi, S

2014-10-01

368

Preparation of tamarind gum based soft ion gels having thixotropic properties.  

PubMed

Tamarind gum was used to prepare ion gels using both synthetic ionic liquids (ILs) namely 1-butyl-3-methylimidazolium chloride and 1-butyl-3-methylimidazolium bromide and bio-based ionic liquids (Bio-ILs) namely choline acrylate, choline caproate and choline caprylate by heating cooling process. The gels were found to have good thermal stability and exhibited thixotropic behaviour. Upon relaxation after applied breaking strain, the recovery of gel structures after ten consecutive cycles was observed. The hydrogel of the gum prepared using ethanol aqueous solution had much inferior quality in terms of viscosity, viscoelasticity, thermal stability and thixotropicity when compared with the ion gels. The ion gels also showed very good adherence to human finger muscles and skin. The ion gels thus prepared may find application in electrochemistry, sensors, actuators and the gels prepared with Bio-ILs could even be useful in biomedical applications. PMID:24507307

Sharma, Mukesh; Mondal, Dibyendu; Mukesh, Chandrakant; Prasad, Kamalesh

2014-02-15

369

Identification of jasmonic acid and its methyl ester as gum-inducing factors in tulips.  

PubMed

The purpose of this study was to identify endogenous factors that induce gummosis and to show their role in gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) stems. Using procedures to detect endogenous factors that induce gum in the stem of tulips, jasmonic acid (JA) and methyl jasmonate (JA-Me) were successfully identified using gas-liquid chromatography-mass spectrometry. Total amounts of JA and JA-Me designated as jasmonates in tulip stems were also estimated at about 70-80 ng/g fresh weight, using deuterium-labeled jasmonates as internal standards. The application of JA and JA-Me as lanolin pastes substantially induced gums in tulip stems with ethylene production. The application of ethephon, an ethylene-generating compound, however, induced no gummosis although it slightly affected jasmonate content in tulip stems. These results strongly suggest that JA and JA-Me are endogenous factors that induce gummosis in tulip stems. PMID:15654503

Skrzypek, Edyta; Miyamoto, Kensuke; Saniewski, Marian; Ueda, Junichi

2005-02-01

370

Interpenetrating polymer network of locust bean gum-poly (vinyl alcohol) for controlled release drug delivery.  

PubMed

A novel interpenetrating polymer network (IPN) microspheres of locust bean gum (LBG) and poly (vinyl alcohol) (PVA) was developed for oral controlled release of buflomedil hydrochloride (BH) by emulsion crosslinking method using glutaraldehyde as crosslinker. The effects of gum-polymer ratio, concentration of crosslinker and internal phase viscosity were evaluated thoroughly. Drug entrapment efficiency, particle size distribution, swelling property and in vitro release characteristics with kinetic modelling of microspheres were evaluated. The microspheres were characterised by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), solid state C(13) NMR, X-ray diffraction study (XRD) and differential scanning colorimetry (DSC). The microspheres showed control release property without showing any incompatibility in IPN device. Hence, IPN microspheres of LBG and PVA can be used as a potential carrier for controlled oral delivery of highly water soluble drugs like BH. PMID:23544563

Kaity, Santanu; Isaac, Jinu; Ghosh, Animesh

2013-04-15

371

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

PubMed

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

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

372

Solution properties of targacanthin (water-soluble part of gum tragacanth exudate from Astragalus gossypinus)  

Microsoft Academic Search

Solution properties of tragacanthin (the water-soluble part of gum tragacanth) were studied by gel permeation chromatography (GPC) combined with multi-angle light scattering and viscometry at 25°C. Photon correlation spectroscopy was used to determine the hydrodynamic radius. Ultrasonic degradation was applied to obtain biopolymer fractions of different molecular weights. The dependence of intrinsic viscosity [?] and radius of gyration ?s2?z1\\/2 on

Mohammad Amin Mohammadifar; Seyed Mohammad Musavi; Amir Kiumarsi; Peter A. Williams

2006-01-01

373

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

PubMed Central

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

T.S., Priyanka

2014-01-01

374

[Gum use efficacy evaluation for chewing muscular system stimulation during orthodontic treatment].  

PubMed

For the treatment of dentition distal dystopia in 10 patients of the age 14-21 years functional fixed telescopic apparatus were used and by the bioelectric activity of the chewing muscular system there was evaluated chewing gum use efficacy for stimulation chewing apparatus rebuilding. After 2 weeks the normalization of occlusive contacts in the lateral parts of dentition happened; after 4 weeks the work of chewing muscular system became coordinated. PMID:19365351

Logatskaia, E B

2009-01-01

375

pH sensitive alginate-guar gum hydrogel for the controlled delivery of protein drugs.  

PubMed

Design of a pH sensitive alginate-guar gum hydrogel crosslinked with glutaraldehyde was done for the controlled delivery of protein drugs. Alginate is a non-toxic polysaccharide with favorable pH sensitive properties for intestinal delivery of protein drugs. Drug leaching during hydrogel preparation and rapid dissolution of alginate at higher pH are major limitations, as it results in very low entrapment efficiency and burst release of entrapped protein drug, once it enters the intestine. To overcome these limitations, another natural polysaccharide, guargum was included in the alginate matrix along with a cross linking agent to ensure maximum encapsulation efficiency and controlled drug release. The crosslinked alginate-guar gum matrix is novel and the drug loading process used in the study was mild and performed in aqueous environment. The release profiles of a model protein drug (BSA) from test hydrogels were studied under simulated gastric and intestinal media. The beads having an alginate to guar gum percentage combination of 3:1 showed desirable characters like better encapsulation efficiency and bead forming properties in the preliminary studies. The glutaraldehyde concentration giving maximum (100%) encapsulation efficiency and the most appropriate swelling characteristics was found to be 0.5% (w/v). Freeze-dried samples showed swelling ratios most suitable for drug release in simulated intestinal media ( approximately 8.5). Protein release from test hydrogels was minimal at pH 1.2 ( approximately 20%), and it was found to be significantly higher ( approximately 90%) at pH 7.4. Presence of guar gum and glutaraldehyde crosslinking increases entrapment efficiency and prevents the rapid dissolution of alginate in higher pH of the intestine, ensuring a controlled release of the entrapped drug. PMID:17147980

George, M; Abraham, T E

2007-04-20

376

Pistachio (Pistacia vera L.) Gum: a potent inhibitor of reactive oxygen species.  

PubMed

Abstract In the present study, in order to evaluate antioxidant and radical scavenging properties of Pistachio gum (P-Gum), different bioanalytical methods such as DPPH(•) scavenging activity, DMPD(•+) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, reducing ability Fe(3+)-Fe(2+) transformation, Cuprac and FRAP assays, [Formula: see text] scavenging by riboflavin-methionine-illuminate system and ferrous ions (Fe(2+)) chelating activities by 2,2'-bipyridyl reagent were performed separately. P-Gum inhibited 54.2% linoleic acid peroxidation at 10?µg/ml concentration. On the other hand, BHA, BHT, ?-tocopherol and trolox, pure antioxidant compounds, indicated inhibition of 80.3%, 73.5%, 36.2% and 72.0% on peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, all of sample had an effective DPPH(•), DMPD(•+) and [Formula: see text] scavenging, Fe(3+) reducing power by Fe(3+)-Fe(2+) transformation and FRAP assay, Cu(2+) reducing ability by Cuprac method and Fe(2+) chelating activities. PMID:24939094

Sehitoglu, M Hilal; Han, Hatice; Kalin, P?nar; Gülçin, Ilhami; Ozkan, Ali; Aboul-Enein, Hassan Y

2014-06-18

377

Diuretic activity of Boswellia serrata Roxb. oleo gum extract in albino rats.  

PubMed

The aim of the study was to evaluate the effect of crude aqueous extract of Boswellia serrata Roxb. oleo gum on urinary electrolytes, pH and diuretic activity in normal albino rats. Moreover, acute toxicity of the gum extract was assessed using mice. Albino rats were divided into five groups. Control group received normal saline (10 mg/kg), reference group received furosemide (10 mg/kg) and test groups were given different doses of crude extract (10, 30 and 50 mg/kg) by intra-peritoneal route, respectively. The Graph Pad Prism was used for the statistical analysis and p < 0.05 was considered statistically significant. Significant diuretic, kaliuretic and natriuretic effects were observed in the treated groups in a dose dependent manner. Diuretic index showed good diuretic activity of the crude extract. Lipschitz values indicated that the crude extract, at the dose of 50 mg/kg, showed 44 % diuretic activity compared to the reference drug. No lethal effects were observed among albino mice even at the higher dose of 3000 mg/kg. It is concluded that aqueous extract of Boswellia serrata oleo gum, at the dose of 50 mg/kg showed significant effects on urinary volume and concentration of urinary electrolytes with no signs of toxicity. PMID:25362605

Asif, Muhammad; Jabeen, Qaiser; Abdul-Majid, Amin Malik-Shah; Atif, Muhammad

2014-11-01

378

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

PubMed

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

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

2015-04-01

379

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

PubMed

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

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

2014-06-01

380

The effect of guar gum on fluid friction in spiral pipe  

NASA Astrophysics Data System (ADS)

Pipeline is the most effective equipment to transport of fluid. Based on the shape, pipe can classify as circular, square, triangle and spiral. Each shape has different characteristics. On the transport of fluid using pipe, pressure drop is very important aspect because related with energy consumption. Special pipe as spiral pipe is used as a fuel mixing system of fuel. It is intended to prevent precipitation and to reduce the pressure drop. The purpose of this research is to investigate the reduction of pressure drop in a spiral pipe with the addition biopolymer (guar gum). Spiral pipe with the best aspect ratio, P/Di = 7 is used in this study. Working fluid used guar gum solution of 150 ppm and 200 ppm. Circular pipe with same diameter is used for comparison. Analysis of flow characteristics based on the power law model for non-Newtonian fluid. Experimental was conducted from low to high Reynolds number up to 60,000. The results showed that the effect of biopolymer guar gum solution can reduce drag either on a circular pipe and spiral pipe.

Yanuar, Gunawan, Baqi, M.

2012-06-01

381

Use of xylitol chewing gum in daycare centers: a follow-up study in Savonlinna, Finland.  

PubMed

The use of toothbrushes in daycare centers has been questioned because of the possibility of infections spreading through unsupervised brushing. Several field studies have demonstrated a caries-preventive effect of xylitol chewing gum--a measure that could be a practical way of taking care of oral hygiene during daycare hours without brushing. A community trial was conducted in Savonlinna, Finland to test the caries-preventive effect of xylitol chewing gum at these centers. A total of 921 children were recruited. The daycare centers were randomly distributed to xylitol chewing gum or brushing groups. An additional 270 children who had not been in daycare centers were later organized into an external reference group in order to check whether the children in the daycare centers were representative of all children in Savonlinna. The results revealed a statistically significant but clinically small difference between the xylitol and brushing groups in favor of the xylitol group. Many families used the daycare services irregularly. Changes in workplace, periods of unemployment, the birth of other children in the family, etc., affect the likelihood of families keeping their children in a daycare center for many years. Despite the fact that conditions were not optimal, oral health status in the xylitol group was a little bit better than in the control group. The use of xylitol can therefore be recommended, especially if the personnel do not have the possibility to supervise the brushing. PMID:14960009

Kovari, Helena; Pienihäkkinen, Kaisu; Alanen, Pentti

2003-12-01

382

[Assessment of three methods for the identification of enzymatically hydrolyzed guar gum].  

PubMed

Enzymatically hydrolyzed guar gum (EHGG), which is used as a thickener or a soluble dietary fiber, is produced by partial hydrolysis of the guar gum (GG) backbone using mannan endo-?-1,4-mannosidase. In this study, we compared and evaluated 3 methods to distinguish EHGG from other polysaccharides used as food additives or monosaccharides. The first method is based on cross-linking reaction of saccharide hydroxyl groups mediated by borate ions. EHGG showed gelation and was distinguished from some soluble polysaccharides, which did not form gels, and also from polysaccharides with low solubility in water. The second method is based on co-gelation with xanthan gum. It was applicable to GG, but not to EHGG. The third method is based on the alcohol precipitation of hydrophilic polymers. EHGG, some soluble polysaccharides and monosaccharides were dissolved in water at the concentration of 10%, while GG and some polysaccharides were not. The 10% solutions thus obtained were mixed with 2-propanol at the ratio of 1 : 1 (v/v). A white precipitate was formed in the EHGG solutions and the tested soluble polysaccharide solutions, while it was not produced in the monosaccharide solutions. This result demonstrated that soluble polysaccharides including EHGG can be distinguished from polysaccharides with low solubility or monosaccharides by the third method. PMID:23470876

Akiyama, Takumi; Sekiguchi, Wakana; Yamazaki, Takeshi; Akiyama, Hiroshi

2013-01-01

383

Bioadhesive Controlled Metronidazole Release Matrix Based on Chitosan and Xanthan Gum  

PubMed Central

Metronidazole, a common antibacterial drug, was incorporated into a hydrophilic polymer matrix composed of chitosan xanthan gum mixture. Hydrogel formation of this binary chitosan-xanthan gum combination was tested for its ability to control the release of metronidazole as a drug model. This preparation (MZ-CR) was characterized by in vitro, ex vivo bioadhesion and in vivo bioavailability study. For comparison purposes a commercial extended release formulation of metronidazole (CMZ) was used as a reference. The in vitro drug-release profiles of metronidazole preparation and CMZ were similar in 0.1 M HCl and phosphate buffer pH 6.8. Moreover, metronidazole preparation and CMZ showed a similar detachment force to sheep stomach mucosa, while the bioadhesion of the metronidazole preparation was higher three times than CMZ to sheep duodenum. The results of in vivo study indicated that the absorption of metronidazole from the preparation was faster than that of CMZ. Also, MZ-CR leads to higher metronidazole Cmax and AUC relative to that of the CMZ. This increase in bioavailability might be explained by the bioadhesion of the preparation at the upper part of the small intestine that could result in an increase in the overall intestinal transit time. As a conclusion, formulating chitosan-xanthan gum mixture as a hydrophilic polymer matrix resulted in a superior pharmacokinetic parameters translated by better rate and extent of absorption of metronidazole. PMID:20559494

Eftaiha, Ala’a F.; Qinna, Nidal; Rashid, Iyad S.; Al Remawi, Mayyas M.; Al Shami, Munther R.; Arafat, Tawfiq A.; Badwan, Adnan A.

2010-01-01

384

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

PubMed

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

Li, Ruoshi; Feke, Donald L

2015-04-01

385

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

PubMed Central

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

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

2014-01-01

386

Gum arabic glycoprotein is a twisted hairy rope. A new model based on O-galactosylhydroxyproline as the polysaccharide attachment site  

Microsoft Academic Search

Separation of the wound exudate from Acacia senegal (L.) Willd., gum arabic, on a preparative Superose-6 column gave two major fractions: a high molecular weight gum arabic glyco-protein (GAGP) containing about 90% carbohydrate and a lower molecular weight heterogeneous gum arabic polysaccharide fraction. Hydrogen fluoride-deglycosylation of GAGP gave a large hydroxyproline-rich polypeptide backbone (dGAGP). Alkaline hydrolysis of GAGP showed that

Wu Qi; C. Fong; D. T. A. Lamport

1991-01-01

387

Effects of guar gum and cellulose on glucose absorption, hormonal release and hepatic metabolism in the pig  

NASA Technical Reports Server (NTRS)

Six Large White pigs (mean body-weight 59 (SE 1.7) kg) were surgically fitted with permanent catheters in the portal vein, the brachiocephalic artery and the right hepatic vein, as well as with electromagnetic flow probes around the portal vein and the hepatic artery, and allowed to recover. The non-anaesthetized animals were given a basal non-fibre diet (diet A) alone or together with 60 g guar gum/kg (diet B) or 150 g purified cellulose/kg (diet C) by substitution for mica. The diets were given for weekly periods and according to a replicated 3 x 3 Latin square design. On the last day of each such adaptation period, test meals of 800 g were given before blood sampling. Sampling was continued for 8 h. Guar gum strongly reduced glucose apparent absorption without changing the absorption and the hepatic uptake profiles. Production rates of insulin, gastric inhibitory polypeptide and insulin-like growth factor-1 (IGF-1) were lowest after guar gum ingestion. However, the reductions in peripheral blood insulin levels caused by guar gum were not associated with a change in hepatic insulin extraction. IGF-1 appeared to be strongly secreted by the gut, whereas the liver had a net uptake of the peptide. Ingestion of guar gum increased the hepatic extraction coefficient of gut-produced IGF-1. Guar gum ingestion appeared also to decrease glucagon secretion. Cellulose at the level consumed had very few effects on the variables considered. It is suggested that the modulation of intestinal mechanisms by guar gum was sufficient to mediate the metabolic effects described.

Nunes, C. S.; Malmlof, K.

1992-01-01

388

Effects of guar gum and cellulose on glucose absorption, hormonal release and hepatic metabolism in the pig.  

PubMed

Six Large White pigs (mean body-weight 59 (SE 1.7) kg) were surgically fitted with permanent catheters in the portal vein, the brachiocephalic artery and the right hepatic vein, as well as with electromagnetic flow probes around the portal vein and the hepatic artery, and allowed to recover. The non-anaesthetized animals were given a basal non-fibre diet (diet A) alone or together with 60 g guar gum/kg (diet B) or 150 g purified cellulose/kg (diet C) by substitution for mica. The diets were given for weekly periods and according to a replicated 3 x 3 Latin square design. On the last day of each such adaptation period, test meals of 800 g were given before blood sampling. Sampling was continued for 8 h. Guar gum strongly reduced glucose apparent absorption without changing the absorption and the hepatic uptake profiles. Production rates of insulin, gastric inhibitory polypeptide and insulin-like growth factor-1 (IGF-1) were lowest after guar gum ingestion. However, the reductions in peripheral blood insulin levels caused by guar gum were not associated with a change in hepatic insulin extraction. IGF-1 appeared to be strongly secreted by the gut, whereas the liver had a net uptake of the peptide. Ingestion of guar gum increased the hepatic extraction coefficient of gut-produced IGF-1. Guar gum ingestion appeared also to decrease glucagon secretion. Cellulose at the level consumed had very few effects on the variables considered. It is suggested that the modulation of intestinal mechanisms by guar gum was sufficient to mediate the metabolic effects described. PMID:1337269

Nunes, C S; Malmlöf, K

1992-11-01

389

Real-time investigation of mannosyltransferase function of a Xylella fastidiosa recombinant GumH protein using QCM-D.  

PubMed

Xylella fastidiosa is a gram-negative bacterium that causes serious diseases in economically important crops, including grapevine, coffee, and citrus fruits. X. fastidiosa colonizes the xylem vessels of the infected plants, thereby blocking water and nutrient transport. The genome sequence of X. fastidiosa has revealed an operon containing nine genes possibly involved in the synthesis of an exopolisaccharide (EPS) named fastidian gum that can be related with the pathogenicity of this bacterium. The ?-1,3-mannosyltransferase (GumH) enzyme from X. fastidiosa is involved in fastidian gum production. GumH is responsible for the transfer of mannose from guanosine diphosphate mannose (GDP-man) to the cellobiose-pyrophosphate-polyprenol carrier lipid (CPP-Lip) during the assembly and biosynthesis of EPS. In this work, a method for real-time detection of recombinant GumH enzymatic activity was successfully developed using a Quartz Crystal Microbalance with dissipation monitoring (QCM-D). The QCM-D transducer was strategically modified with CPP-Lip by using a solid-supported lipid bilayer that makes use of a self-assembled monolayer of 1-undecanethiol. Monitoring the real-time CPP-Lip QCM-D transducer in the presence of GDP-man and GumH enzyme shows a mass increase, indicating the transfer of mannose. The real-time QCM-D determination of mannosyltransferase function was validated by a High Performance Liquid Chromatography (LC) method developed for determination of GDP produced by enzymatic reaction. LC results confirmed the activity of recombinant GumH protein, which is the first enzyme involved in the biosynthesis of the EPS from X. fastidiosa enzymatically characterized. PMID:21521632

Alves, Claudia A; Pedroso, Mariele M; de Moraes, Marcela C; Souza, Dulce H F; Cass, Quezia B; Faria, Ronaldo C

2011-05-20

390

Effect of gum tragacanth on rheological and physical properties of a flavored milk drink made with date syrup.  

PubMed

Date syrup as a nutritional additive and safe alternative to added sugar is one of the best choices for milk flavoring. In this study, a flavored milk beverage was formulated using date syrup for flavoring the product and gum tragacanth to obtain an acceptable mouth feel. Steady shear and dynamic oscillatory rheological properties of the samples contained 3 concentrations (0, 0.1, 0.2, and 0.3%, wt/wt) of 2 types of gum tragacanth (Astragalus gossypinus and Astragalus rahensis) which at 3°C, were studied. Particle size distribution and colorimetric assays were determined by laser diffractometry and using reflection spectrometer, respectively. Sensory analysis was performed with 25 semitrained panelists, using a 5-point hedonic scale. The results showed that viscoelastic properties, flow behavior parameters, particle size, and color parameters (L*, a*, and b*, where L* represents lightness, a* represents the redness/greenness quality of the color, and b* represents the yellowness and blueness quality of the colors) were significantly affected by the concentration of the gum tragacanth and the severity of this effect was influenced by the type of gum. The use of appropriate type and concentration of gum tragacanth in date milk formulation can improve the texture and mouth feel by affecting on particle size and the flow behavior of this product. PMID:23746580

Keshtkaran, Maryam; Mohammadifar, Mohammad Amin; Asadi, Gholam Hassan; Nejad, Reza Azizi; Balaghi, Sima

2013-08-01

391

Development of reduced-fat mayonnaise using 4alphaGTase-modified rice starch and xanthan gum.  

PubMed

In this study a disproportionating enzyme, 4-alpha-glucanotransferase (4alphaGTase), was used to modify the structural properties of rice starch to produce a suitable fat substitute in reduced-fat (RF) mayonnaise. The mayonnaise fat was partially substituted with the 4alphaGTase-treated starch paste at levels up to 50% in combination with xanthan gum and the physical and rheological properties of the modified RF mayonnaise samples were investigated. All mayonnaises prepared in this study exhibited shear thinning behavior and yield stress. Viscoelastic properties of mayonnaise were characterized using dynamic oscillatory shear test and it was observed that mayonnaises exhibited weak gel-like properties. The magnitude of elastic and loss moduli was also affected by 4alphaGTase-treated starch concentration and presence of xanthan gum. In relation to microstructure, RF mayonnaise prepared with 3.8 or 5.6 wt% of 4alphaGTase-treated starch and xanthan gum showed smaller droplets. The use of 5.6 wt% of 4alphaGTase-treated starch and 0.1 wt% of xanthan gum produced a RF mayonnaise with similar rheological properties and appearances as FF mayonnaise with gum. This study demonstrated a high feasibility for using 4alphaGTase-treated rice starch as a viable fat replacer in mayonnaise. PMID:19428473

Mun, Saehun; Kim, Young-Lim; Kang, Choon-Gil; Park, Kwan-Hwa; Shim, Jae-Yong; Kim, Yong-Ro

2009-06-01

392

Beneficial properties of selenium incorporated guar gum nanoparticles against ischemia/reperfusion in cardiomyoblasts (H9c2).  

PubMed

Nanotechnology for the treatment and diagnosis has been emerging recently as a potential area of research and development. In the present study, selenium incorporated guar gum nanoparticles have been prepared by nanoprecipitation and characterized by transmission electron microscopy and particle size analysis. The nanoparticles were screened for antioxidant potential (metal chelation, total reducing power and hydroxyl radical scavenging activity) and were evaluated against the cell line based cardiac ischemia/reperfusion model with special emphasis on oxidative stress and mitochondrial parameters. The cell based cardiac ischemia model was employed using H9c2 cell lines. Investigations revealed that there was a significant alteration (P ? 0.05) in the innate antioxidant status (glutathione?, glutathione peroxidase?, thioredoxin reductase?, superoxide dismutase?, catalase?, lipid peroxidation?, protein carbonyl?, xanthine oxidase? and caspase 3 activity?), mitochondrial functions (reactive oxygen species generation, membrane potential, and pore opening) and calcium homeostasis (calcium ATPase and intracellular calcium overload) during both ischemia and reperfusion. For comparative evaluation, selenium, guar gum and selenium incorporated guar gum nanoparticles were evaluated for their protective properties against ischemia/reperfusion. The study reveals that selenium incorporated guar gum nanoparticles were better at protecting the cells from ischemia/reperfusion compared to selenium and guar gum nanoparticles. The potent antioxidant capability shown by the sample in in vitro assays may be the biochemical basis of its better biological activity. Further, the nanodimensions of the particle may be the additional factor responsible for its better effect. PMID:25307064

Soumya, R S; Vineetha, V P; Salin Raj, P; Raghu, K G

2014-11-01

393

Size-controlled green synthesis of silver nanoparticles mediated by gum ghatti (Anogeissus latifolia) and its biological activity  

PubMed Central

Background Gum ghatti is a proteinaceous edible, exudate tree gum of India and is also used in traditional medicine. A facile and ecofriendly green method has been developed for the synthesis of silver nanoparticles from silver nitrate using gum ghatti (Anogeissus latifolia) as a reducing and stabilizing agent. The influence of concentration of gum and reaction time on the synthesis of nanoparticles was studied. UV–visible spectroscopy, transmission electron microscopy and X-ray diffraction analytical techniques were used to characterize the synthesized nanoparticles. Results By optimizing the reaction conditions, we could achieve nearly monodispersed and size controlled spherical nanoparticles of around 5.7 ± 0.2 nm. A possible mechanism involved in the reduction and stabilization of nanoparticles has been investigated using Fourier transform infrared spectroscopy and Raman spectroscopy. Conclusions The synthesized silver nanoparticles had significant antibacterial action on both the Gram classes of bacteria. As the silver nanoparticles are encapsulated with functional group rich gum, they can be easily integrated for various biological applications. PMID:22571686

2012-01-01

394

Effect of incorporation of pumpkin (Cucurbita moshchata) powder and guar gum on the rheological properties of wheat flour.  

PubMed

The present study was carried out to study the effect of incorporation of fibre rich pumpkin powder and guar gum on the farinographic characteristics of wheat flour. The flour and pumpkin powder were assessed for proximate composition, total dietary fibre, minerals and ?-carotene. Pumpkin powder contained appreciable amount of fibre, minerals and ?-carotene. The effects of incorporation of different levels of pumpkin powder and guar gum along with pumpkin powder on farinographic characteristics were studied. Dough development time, dough stability, time to break down and farinograph quality number increased whereas mixing tolerance index decreased with incorporation of pumpkin powder (> 5 %) and guar gum (1.0 and 1.5 %) along with pumpkin powder in the flour. Resistance to extension as well as extensibility of dough prepared increased significantly by adding pumpkin powder (5-15 %) whereas increase in resistance to extension only was noticed with inclusion of guar gum (0.5-1.5 %) to flour containing 5 % pumpkin powder. Results indicated that pumpkin can be processed to powder that can be utilized with guar gum for value addition. PMID:25328201

Kundu, Himani; Grewal, Raj Bala; Goyal, Ankit; Upadhyay, Neelam; Prakash, Saurabh

2014-10-01

395

Characterization and preliminary toxicity assay of nano-titanium dioxide additive in sugar-coated chewing gum.  

PubMed

Nanotechnology shows great potential for producing food with higher quality and better taste through including new additives, improving nutrient delivery, and using better packaging. However, lack of investigations on safety issues of nanofood has resulted in public fears. How to characterize engineered nanomaterials in food and assess the toxicity and health impact of nanofood remains a big challenge. Herein, a facile and highly reliable separation method of TiO2 particles from food products (focusing on sugar-coated chewing gum) is reported, and the first comprehensive characterization study on food nanoparticles by multiple qualitative and quantitative methods is provided. The detailed information on nanoparticles in gum includes chemical composition, morphology, size distribution, crystalline phase, particle and mass concentration, surface charge, and aggregation state. Surprisingly, the results show that the number of food products containing nano-TiO2 (<200 nm) is much larger than known, and consumers have already often been exposed to engineered nanoparticles in daily life. Over 93% of TiO2 in gum is nano-TiO2 , and it is unexpectedly easy to come out and be swallowed by a person who chews gum. Preliminary cytotoxicity assays show that the gum nano-TiO2 particles are relatively safe for gastrointestinal cells within 24 h even at a concentration of 200 ?g mL(-1) . This comprehensive study demonstrates accurate physicochemical property, exposure, and cytotoxicity information on engineered nanoparticles in food, which is a prerequisite for the successful safety assessment of nanofood products. PMID:23065899

Chen, Xin-Xin; Cheng, Bin; Yang, Yi-Xin; Cao, Aoneng; Liu, Jia-Hui; Du, Li-Jing; Liu, Yuanfang; Zhao, Yuliang; Wang, Haifang

2013-05-27

396

Effect of partially depolymerized guar gum on acute metabolic variables in patients with non-insulin-dependent diabetes.  

PubMed

Fourteen patients with non-insulin-dependent diabetes (NIDDM) attended the study centre on 4 mornings separated by at least 3 days, to receive in random order 75 g carbohydrate breakfast meals of control or guar breads with jam and butter. Guar gum flours of low, medium, and high molecular weight (MW) were incorporated into wheat bread rolls to provide 7.6 g guar per meal. Venous blood samples were taken via an indwelling cannula in a forearm vein at fasting and at eight postprandial times and then analysed for blood glucose, plasma insulin, C-peptide, and gastric inhibitory polypeptide (GIP). Guar gum bread significantly reduced the postprandial rise in blood glucose, plasma insulin, and, except for bread containing low MW guar gum, plasma GIP levels compared to the control. Thus, the partial depolymerization of guar gum does not diminish its physiological activity. No reductions in postprandial plasma C-peptide levels were seen after any of the guar bread meals. This suggests that guar gum attenuates the insulin concentration in peripheral venous blood in patients with NIDDM by increasing the hepatic extraction of insulin. PMID:9162612

Gatenby, S J; Ellis, P R; Morgan, L M; Judd, P A

1996-04-01

397

Reliability and validity of a quantitative color scale to evaluate masticatory performance using color-changeable chewing gum.  

PubMed

In the present study, we developed a novel color scale for visual assessment, conforming to theoretical color changes of a gum, to evaluate masticatoryperformance; moreover, we investigated the reliability and validity of this evaluation method using the color scale. Ten participants (aged 26.30 years) with natural dentition chewed the gum at several chewing strokes. Changes in color were measured using a colorimeter, and then, linearregression expressions that represented changes in gum color were derived. The color scale was developed using these regression expressions. Thirty-two chewed gums were evaluated using colorimeter and were assessed three times using the color scale by six dentists aged 25.27 (mean, 25.8) years, six preclinical dental students aged 21.23 (mean, 22.2) years, and six elderly individuals aged 68.84 (mean, 74.0) years. The intrarater and interrater reliability of evaluations was assessed using intraclass correlation coefficients. Validity of the method compared with a colorimeter was assessed using Spearman's rank correlation coefficient. All intraclass correlation coefficients were > 0.90, and Spearman's rank-correlation coefficients were > 0.95 in all groups. These results indicated that the evaluation method of the color-changeable chewing gum using the newly developed color scale is reliable and valid. PMID:24658959

Hama, Yohei; Kanazawa, Manabu; Minakuchi, Shunsuke; Uchida, Tatsuro; Sasaki, Yoshiyuki

2014-01-01

398

Effects of Guar Gum And Soybean Dietary Fiber on The Control of Glucose and Lipid Metabolism in Normal and Diabetic Rats: A Comparative Study  

Microsoft Academic Search

The use of natural plant fibers in the management of metabolic disorders is increasing nowadays. The beneficial effects of guar gum and soybean fiber are well known. The present study was designed to compare the effects of 45-day feeding of guar gum (soluble fiber) or soybean fiber to normal and diabetic rats. This was achieved by performing oral glucose tolerance

Sherif H. Ahmed; Ashraf B. Abdel-Naim

399

Serum Concentrations and Accumulation of Silver in Skin During Three Months Treatment with an Anti-smoking Chewing Gum containing Silver Acetate  

Microsoft Academic Search

Silver acetate chewing gum was used for 12 weeks as a smoking deterrent in 21 adults. The effect of silver on serum concentrations, its accumulation in the skin and the risk of developing clinically evident argyria were investigated. Serum concentrations of silver clearly rose after chewing gum use had started, and concentrations quickly returned to normal after use had ceased.

E. J. Jensen; J. Rungby; J. C. Hansen; E. Schmidt; B. Pedersen; R. Dahl

1988-01-01

400

DAIRY FOODS TECHNICAL NOTES Changes in Electrical Energy Requirements to Operate an Ice Cream Freezer as a Function of Sweeteners and Gums  

Microsoft Academic Search

Changes in electrical energy required to operate a continuous freezer were monitored for various ice cream for- mulae. Ice cream formulae consisted of nine different combinations of sucrose, 36 DE corn syrup, and 42 high fructose corn syrup as well as two ratios of guar gum to locust bean gum. Within the same sweetening system, a mix high in locust

D. E. SMITH; A. S. BAKSHI; S. A. GAY

401

A study of the effects of aeration and agitation on the properties and production of xanthan gum from crude glycerin derived from biodiesel using the response surface methodology.  

PubMed

The effects of aeration and agitation on the properties and production of xanthan gum from crude glycerin biodiesel (CGB) by Xanthomonas campestris mangiferaeindicae 2103 were investigated and optimized using a response surface methodology. The xanthan gum was produced from CGB in a bioreactor at 28 °C for 120 h. Optimization procedures indicated that 0.97 vvm at 497.76 rpm resulted in a xanthan gum production of 5.59 g L(-1) and 1.05 vvm at 484.75 rpm maximized the biomass to 3.26 g L(-1). Moreover, the combination of 1.05 vvm at 499.40 rpm maximized the viscosity of xanthan at 0.5% (m/v), 25 °C, and 25 s(-1) (255.40 mPa s). The other responses did not generate predictive models. Low agitation contributed to the increase of xanthan gum production, biomass, viscosity, molecular mass, and the pyruvic acid concentration. Increases in the agitation contributed to the formation of xanthan gum with high mannose concentration. Decreases in the aeration contributed to the xanthan gum production and the formation of biopolymer with high mannose and glucose concentrations. Increases in aeration contributed to increased biomass, viscosity, and formation of xanthan gum with greater resistance to thermal degradation. Overall, aeration and agitation of CGB fermentation significantly influenced the production of xanthan gum and its properties. PMID:24435765

de Jesus Assis, Denilson; Brandão, Líllian Vasconcelos; de Sousa Costa, Larissa Alves; Figueiredo, Tamiris Vilas Boas; Sousa, Luciane Santos; Padilha, Francine Ferreira; Druzian, Janice Izabel

2014-03-01

402

Chewing gum alleviates negative mood and reduces cortisol during acute laboratory psychological stress.  

PubMed

The notion that chewing gum may relieve stress was investigated in a controlled setting. A multi-tasking framework which reliably evokes stress and also includes performance measures was used to induce acute stress in the laboratory. Using a randomised crossover design forty participants (mean age 21.98 years) performed on the multi-tasking framework at two intensities (on separate days) both while chewing and not chewing. Order of workload intensity and chewing conditions were counterbalanced. Before and after undergoing the platform participants completed the state portion of the State-Trait Anxiety Inventory, Bond-Lader visual analogue mood scales, a single Stress Visual Analogue Scale and provided saliva samples for cortisol measurement. Baseline measures showed that both levels of the multi-tasking framework were effective in significantly reducing self-rated alertness, calmness and contentment while increasing self-rated stress and state anxiety. Cortisol levels fell during both levels of the stressor during the morning, reflecting the predominance of a.m. diurnal changes, but this effect was reversed in the afternoon which may reflect a measurable stress response. Pre-post stressor changes (Delta) for each measure at baseline were subtracted from Delta scores under chewing and no chewing conditions. During both levels of stress the chewing gum condition was associated with significantly better alertness and reduced state anxiety, stress and salivary cortisol. Overall performance on the framework was also significantly better in the chewing condition. The mechanisms underlying these effects are unknown but may involve improved cerebral blood flow and/or effects secondary to performance improvement during gum chewing. PMID:19268676

Scholey, Andrew; Haskell, Crystal; Robertson, Bernadette; Kennedy, David; Milne, Anthea; Wetherell, Mark

2009-06-22

403

What can we learn from the saga of chitosan gums in hyperphosphatemia therapy?  

PubMed

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

Oh, Man S; Uribarri, Jaime

2014-05-01

404

Variations in tongue-palate swallowing pressures when swallowing xanthan gum-thickened liquids.  

PubMed

Thickened liquids are frequently recommended to reduce the risk of aspiration in patients with oropharyngeal dysphagia. Although it has previously been reported that tongue-palate pressures increase when swallowing spoon-thick and semi-solid consistencies compared to thin liquids, relatively little is known about how swallowing behaviors differ when swallowing liquids of nectar- or honey-thick consistency. Furthermore, previous studies have primarily used starch-based thickeners, and little is known about swallowing behaviors with xanthan gum-thickened liquids, which have recently been introduced for dysphagia management. In this study, we measured variations in tongue-palate pressures during the swallowing of liquids thickened to apparent viscosities of 190, 250, and 380 mPa s at 50/s using increasing concentrations of xanthan gum (0.5, 0.63 and 0.87 w/w%). The viscosity differences between these nectar- and honey-thick stimuli were confirmed to exceed sensory perceptual discrimination thresholds. Data were collected from 78 healthy adults in two sex-balanced age-groups (young; mature) and compared to reference values obtained during water swallowing. The results confirm that increased amplitudes of tongue-palate pressure were used when swallowing the thickened liquid stimuli, compared to swallows of water, and for the honey-thick liquid compared to the two nectar-thick liquids. Age-related reductions were seen in tongue strength but not in swallowing pressures, which fell below 40 % of maximum isometric pressure values. Thus, the use of xanthan gum-thickened liquids is unlikely to tax the swallowing system in terms of tongue pressure generation requirements, even in seniors with reduced maximum isometric tongue pressure measures. PMID:25087111

Steele, Catriona M; Molfenter, Sonja M; Péladeau-Pigeon, Melanie; Polacco, Rebecca C; Yee, Clemence

2014-12-01

405

Factors affecting prednisolone release from hydrogels prepared with water-soluble dietary fibers, xanthan and locust bean gums.  

PubMed

The release behavior of prednisolone from hydrogels prepared with xanthan and locust bean gums was investigated. Newly developed equipment was employed in order to increase the gum concentration in the hydrogels. The apparent release rate of prednisolone from the hydrogels decreased with increasing gum concentration, suggesting that the diffusion of drug molecules was mainly controlled by the density of the three-dimensional network structure in the matrix. The effect of additives such as glycerin and sucrose on the release behavior of prednisolone was also investigated in detail. Drug release was significantly lowered by the addition of these compounds to these hydrogels. A linear relation was observed between the apparent release rate of prednisolone and microscopic viscosity of the hydrogels. These results indicated that the drug release could be controlled not only by the density of the network structure but also by the microscopic viscosity of the hydrogels. PMID:1606645

Watanabe, K; Yakou, S; Takayama, K; Machida, Y; Nagai, T

1992-02-01

406

Effect of guar gum on hunger and satiety after meals of differing fat content: relationship with gastric emptying.  

PubMed

To determine whether the satiating effects of fiber are due to delaying gastric emptying or slowing absorption of meals, 3% guar gum was added to high- and low-fat soups and gastric emptying rate, hunger, and satiety were measured in eight male volunteers. Guar gum delayed the emptying of the low-fat soup but the small delays in the return of hunger and decline of fullness were significantly correlated with the gastric emptying, suggesting mediation by gastric mechanoreceptors. The high-fat soup also emptied more slowly but this had no effect on the return of hunger or the decline in fullness. The delays in the return of hunger and decline of fullness were far greater when guar gum was added to the fatty soup; these delays were not correlated with the small additional delay in gastric emptying. This is more compatible with slowed absorption and prolonged contact of nutrients with intestinal chemoreceptors. PMID:8279409

French, S J; Read, N W

1994-01-01

407

Sonication-Based Improvement of the Physicochemical Properties of Guar Gum as a Potential Substrate for Modified Drug Delivery Systems  

PubMed Central

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

Ansari, Siddique Akber; Cencetti, Claudia; Carafa, Maria; Mazzuca, Claudia; Capitani, Donatella; Coviello, Tommasina

2013-01-01

408

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

PubMed Central

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

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

2014-01-01

409

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

NASA Astrophysics Data System (ADS)

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.

del Campo, D.; García, C.; Ruiz, S.

2013-09-01

410

Inhibition of aluminium and mild steel corrosion in acidic medium using Gum Arabic  

Microsoft Academic Search

The corrosion behaviour of mild steel and aluminium exposed to H2SO4 solution and their inhibition in H2SO4 containing 0.1–0.5 g\\/L Gum Arabic (GA) used as inhibitor was studied at temperature range of 30–60 °C using weight loss and\\u000a thermometric techniques. Corrosion rate increased both in the absence and presence of inhibitor with increase in temperature.\\u000a Corrosion rate was also found to decrease

S. A. Umoren

2008-01-01

411

Effect of Guar Gum on the Physicochemical, Thermal, Rheological and Textural Properties of Green Edam Cheese  

Microsoft Academic Search

In attempts to produce a low-fat cheese with a rheology and texture similar to that of a full-fat cheese, guar gum (within\\u000a 0.0025–0.01%; w\\/v, final concentration) was added to low-fat milk. The obtained cheeses were characterised regarding their physicochemical,\\u000a thermal, rheological and textural properties. Control cheeses were also produced with low and full-fat milk. The physicochemical\\u000a properties of the guar

Nuno M. Oliveira; Fernando Q. Dourado; António M. Peres; Marta V. Silva; João M. Maia; José. A. Teixeira

412

Solubility of calcium soaps of gum rosin, rosin acids and fatty acids  

Microsoft Academic Search

Summary  The solubility of calcium soaps of rosin acids and fatty acids have been determined and compared.\\u000a \\u000a The solubility of calcium soaps of rosin acids (d-pimaric, dihydroabietic, and l-abietic acids) present in gum rosin was found\\u000a to be greater than that of the calcium soaps of the following saturated fatty acids: lauric, myristic, palmitic, and stearic\\u000a acids.\\u000a \\u000a \\u000a \\u000a The calcium oleate was

W. D. Pohle

1941-01-01

413

The influence of Guar gum on absorption of metformin from the gut in healthy volunteers.  

PubMed

Dietary fibre and biproducts of some vegetable extracts (Guar etc.) are advocated to reduce postprandial hyperglycaemia but there is some evidence that these may disturb the absorption kinetics of orally administered drugs. The effect of Guar gum on the digestive absorption of metformin was tested in 6 healthy subjects given 1700 mg of metformin with a standardised meal. Metformin blood levels showed that when given together with Guar there was a reduction in the absorption rate over the first 6 hours. These findings suggest that combination therapy may diminish the anti-hyperglycaemic action of metformin. PMID:2722133

Gin, H; Orgerie, M B; Aubertin, J

1989-02-01

414

[Individual treatment of smoking addiction. Results using 2 and 4 mg nicotine gum].  

PubMed

We present the results of an open follow-up study aimed at analyzing the efficacy of combining psychological counseling with prescription of 2 and 4 mg nicotine gum to treat smokers. Two groups of smokers wer studied. Group A contained 124 subjects (74 men, 50 women) with a mean age of 37.4 (15.3) yr who were smokers of 15.3 (8.7) cigarettes/day. In this group physical addiction to nicotine was low, assessed as 1.7 (1.3) on the Fagerström test. Group B consisted of 107 subjects (61 men, 46 women) with a mean age of 38.9 (14.6) who were smokers of 26.9 (9.3) cigarettes/day and whose level of physical addiction to nicotine was moderate-to-high, assessed as 6.1 (2.4) on the Fagerström test. Standard deviations are shown between parentheses. Both groups were given minimal psychological counseling; additionally, patients were prescribed one piece of nicotine gum very 90 to 120 minutes during waking hours (2 mg in group A and 4 mg in group B). The dose was gradually reduced after the sixth to the eight week. The subjects were seen eight times over the first year (first day of consultation and during the first, second, fourth, eight and twelfth weeks after quitting, and again after six and twelve months). After twelve weeks of follow-up, sixty-one subjects (49%) in group A and 50 (47%) in group B were still abstinent. These proportions fell to 56 (45%) and 46 (43%), respectively, after one year of follow-up. Eighty-one percent of group A patients who were successful after three months of follow-up, and 87% of the successful group B patients, had used the nicotine gum as prescribed. Oropharyngeal, dental, and temporo-mandibular joint symptoms, hiccoughins, flatulence and heartburn were the most frequent side effects (ranging from 3% to 18%). Side effects were always slight and were not detected after the eighth week of treatment. In conclusion, combined therapy (minimal psychological counseling plus use of 2 or 4 mg nicotine gum depending on the level of physical addiction) yields a success rate between 43% and 45% still abstaining after one year of follow-up. Side effects are few and mild. PMID:10782263

Jiménez Ruiz, C A; Cisneros, C; Perelló Bosch, O; Barruero Ferrero, M; Hernández Mezquita, M A; Solano Reina, S

2000-03-01

415

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

NASA Astrophysics Data System (ADS)

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.

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

2015-03-01

416

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

PubMed

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

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

2014-03-01

417

Multi-temporal and Change Analysis of Land Use Land Cover in the Gum Arabic Belt in Kordofan, Sudan  

NASA Astrophysics Data System (ADS)

The gum arabic belt in Sudan plays a significant role in environmental, social and economical aspects. The belt has suffered from deforestation and degradation due to natural hazards and human activities. The research was conducted in North Kordofan State, which is affected by modifications in conditions and composition of vegetation cover trends in the gum arabic belt as in the rest of the Sahelian Sudan zone. The research investigated the possibility of identification, monitoring and mapping of the land use land cover changes and dynamics in the gum arabic belt during the last 35 years. Also a newly approach of object-based classification was applied for image classification. The study used imageries from different satellites (Landsat and ASTER) and multi-temporal dates (MSS 1972, TM 1985, ETM+ 1999 and ASTER 2007) acquired in dry season (November). The imageries were geo-referenced and radiometrically corrected by using ENVI-FLAASH software. Application of multi-temporal remote sensing data in gum arabic belt demonstrated successfully the identification and mapping of land use land cover into five main classes. Forest dominated by Acacia senegal class was separated covering an area of 21% and 24% in the year 2007 for areas A and B, respectively. The land use land cover structure in the gum arabic belt has obvious changes and reciprocal conversions between the classes indicating the trends and conditions caused by the human interventions as well as ecological impacts on Acacia senegal trees. The study revealed a drastic loss of Acacia senegal cover by 25% during the period of 1972 to 2007. The study come out with some valuable recommendations and comments which could contribute positively in using remotely sensed imagery and GIS techniques to explore management tools of Acacia senegal stands in gum Arabic belt.

Adam, Hassan Elnour; Csaplovics, Elmar

2012-07-01

418

Nutritional benefits of Crematogaster mimosae ants and Acacia drepanolobium gum for patas monkeys and vervets in Laikipia, Kenya.  

PubMed

Patas monkeys (Erythrocebus patas) are midsized primates that feed extensively on the gum of Acacia drepanolobium and the ants are housed in swollen thorns of this Acacia. Their diet resembles that expected more of smaller bodied primates. Patas monkeys are also more like smaller bodied primates in reproducing at high rates. We sought to better understand the convergence of patas monkeys with smaller bodied primates by comparing their feeding behavior on ants and gum with that of closely related, sympatric vervets (Chlorocebus pygerythrus), and analyzing the nutrient content of the gum of A. drepanolobium and of Crematogaster mimosae, the most common ant species eaten by patas monkeys in Laikipia, Kenya. All occurrences of feeding and moving during focal animal sampling revealed that 1) patas monkeys seek A. drepanolobium gum but vervets avoid it; 2) both species open swollen thorns most often in the morning when antsare less active; 3) patas monkeys continually feed onswollen thorns and gum while moving quickly throughout the day, whereas vervets reduce their consumption of these items and their travel rate at mid-day, and; 4) vervets eat young swollen thorns at a higher rate than patas monkeys. Patas monkeys are able to spend little time acquiring substantial amounts of energy, protein, and minerals from A. drepanolobium gum and C. mimosae ants each day. These findings, when coupled with evidence of causes of infant and adult female mortality, suggest that reproductive success of female patas monkeys is more immediately affected by illness, disease, interactions between adults and infants, and access to water than by food. PMID:23280312

Isbell, Lynne A; Rothman, Jessica M; Young, Peter J; Rudolph, Kathleen

2013-02-01

419

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

PubMed Central

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

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

2014-01-01

420

The use of molecular dynamics for the study of solution properties of guar gum  

NASA Astrophysics Data System (ADS)

Size exclusion chromatography with dual detection, i.e., employing a refractive index, concentration sensitive, detector together with a multiangle light scattering detector which is sensitive to molecular size, has been applied to study the solution properties of guar gum in water with different concentrations of K2SO4 at 25 °C. The analysis of a single highly polydisperse sample is enough for obtaining calibration curves for molecular weight and radius of gyration and the scaling law coefficients. The influence of the ionic strength on the conformational properties of the polymer can also be analyzed. Moreover, unperturbed dimensions can be obtained by extrapolation of the values measured in a good solvent. The value of the characteristic ratio of the unperturbed dimensions thus obtained is Cn=0/nl2?19±1. A theoretical analysis is also included. Thus, molecular dynamics procedures were employed to analyze the conformational properties of an oligomer of guar gum under different conditions; namely, standing alone in vacuo, in bulk solid state and in water solution, both with and without salt. These conformational properties were then employed to compute molecular dimensions of Monte Carlo generated chains with different lengths according to standard procedures of the matrix multiplication scheme, thus allowing the evaluation of both perturbed and unperturbed dimensions which are in very good agreement with the experimental values. Moreover our result permits the explanation of the discrepancies among experimental and theoretical values reported in the literature.

Laguna, M. Teresa R.; Tarazona, M. Pilar; Saiz, Enrique

2003-07-01

421

Fabrication and fluorescent labeling of guar gum nanoparticles in a surfactant free aqueous environment.  

PubMed

Guar gum (GG) is a galactomannan obtained from the seeds of Cyamopsis tetragonoloba. GG polysaccharide is used in a range of technology arenas and its properties in water environment elicited a lot of interest. We report a simple acid hydrolysis technique to derive water dispersible spherical nanoparticles from GG for the first time without any stabilizing surfactant. The particles demonstrated colloidal stability and were observed to carry negative surface charges in aqueous environment. The TEM study of guar gum nanoparticles (GGn) indicated a size range of 30-80 nm with a mean at 48.8 nm. Mineral acid at apposite concentration have apparently solubilized the amorphous regions of the polymer chain leaving the crystalline parts. GGn were further covalently functionalized in aqueous environment with fluorescein isothiocyanate (FITC) using a hydroxy-propyl amine spacer group. Nanoparticle fluorescence intensity can be modulated with pH changes and a significant augmentation in the intensity was noticed at the physiologically relevant range of 6-8. New fluorescently labeled nanoparticles have potential for applications in bioimaging, biomolecular interaction studies and as a pH sensing probe in sub cellular environment. PMID:25492017

Ghosh, Sumanta Kumar; Abdullah, Farooque; Mukherjee, Arup

2015-01-01

422

New intrinsic mechanism on gum-like superelasticity of multifunctional alloys  

PubMed Central

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

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

423

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

PubMed

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

Sarika, P R; James, Nirmala Rachel

2015-05-01

424

Gum Tragacanth Fibers from Astragalus gummifer Species: Effects of Influencing Factors on Mechanical Properties of Fibers  

NASA Astrophysics Data System (ADS)

Gum Tragacanth (GT) is one of the most widely used natural gum across the globe and it is shown that GT from Asteragalus gummifer can be processed into fiber via alkaline treatment. In this study a complementary description of GT fibers is provided and the effects of influencing factors on properties of GT fibers investigated. Spinning Dope (SD) prepared by adding ribbon type GT of Astragalus gummifer species to alkaline solutions and fibers produced by solution spinning method. The effects of some processing factors including: draft ratio, residence time in coagulation bath, GT concentration in SD, ripening time of SD, kind of coagulant agent and the pH of washing bath on some mechanical properties of GT fibers studied. It was concluded that with increasing the coagulant concentration the mechanical properties of fibers improved, but it caused formation of sheet core structure. ZnCl2 as coagulant agent improved mechanical properties and applying glycerol caused more flexibility in GT fibers, even though their tenacity reduced.

Khajavi, Ramin; Mossavi Pourgharbi, Seyed Hossein; Kiumarsi, Amir; Rashidi, Abosayeed

425

Rheological behavior of xanthan gum solution related to shear thinning fluid delivery for subsurface remediation.  

PubMed

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

Zhong, L; Oostrom, M; Truex, M J; Vermeul, V R; Szecsody, J E

2013-01-15

426

Review: Chios mastic gum: a plant-produced resin exhibiting numerous diverse pharmaceutical and biomedical properties.  

PubMed

Chios mastic gum (CMG) is a resin produced by the plant Pistacia lentiscus var. chia. CMG is used to extract the mastic gum essential oil (MGO). CMG and MGO consist of nearly 70 constituents and have demonstrated numerous and diverse biomedical and pharmacological properties including (a) eradication of bacteria and fungi that may cause peptic ulcers, tooth plaque formation and malodor of the mouth and saliva; (b) amelioration or dramatic reduction of symptoms of autoimmune diseases by inhibiting production of pro-inflammatory substances by activated macrophages, production of cytokines by peripheral blood mononuclear cells in patients with active Crohn's disease, and suppression of production of inflammatory cytokines and chemokines in an asthma model in mice; (c) protection of the cardiovascular system by effectively lowering the levels of total serum cholesterol, low-density lipoprotein and triglycerides in rats, and protection of low-density lipoprotein from oxidation in humans; (d) induction of apoptosis in human cancer cells in vitro and extensive inhibition of growth of human tumors xenografted in immunodeficient mice; and (e) improvement of symptoms in patients with functional dyspepsia. Collectively taken, these numerous and diverse medical and pharmaceutical properties of CMG and MGO warrant further research in an effort to enhance specific properties and identify specific constituent(s) that might be associated with each property. PMID:22949590

Dimas, Konstantinos S; Pantazis, Panayotis; Ramanujam, Rama

2012-01-01

427

Morphological changes in Streptococcus mutans after chewing gum containing xylitol for twelve months.  

PubMed

Few studies have been conducted to evaluate the effect of xylitol on the virulence and morphology of Streptococcus mutans (S. mutans). This study was conducted to evaluate changes in the morphology and virulence of S. mutans in response to long-term consumption of gum containing xylitol. Participants were voluntarily recruited for a women's oral health prevention program, classified into two groups (a control and a xylitol group), and then followed for 1 year. Ten salivary samples were randomly selected from each group. Colony count, field emission scanning electron microscopy, and real-time reverse transcription polymerase chain reaction were used to analyze the characteristics of S. mutans. In the xylitol group, the colony counts of S. mutans decreased steadily over time. In addition, the adherence of the colonies in the xylitol group became weak, and the size of the colonies decreased compared to the control. The secretion of sticky substances from the surface of S. mutans colonies and gtfB gene expression also decreased in the xylitol group. These findings indicate that regular chewing of xylitol gum over a long period may lead to decreased gtfB expression, which can negatively affect the synthesis of extracellular polysaccharides by S. mutans, which could reduce the size and growth of S. mutans colonies and change their morphology as a result. PMID:19085034

Lee, Young-Eun; Choi, Youn-Hee; Jeong, Seong-Hwa; Kim, Hee-Sook; Lee, Sung-Hee; Song, Keun-Bae

2009-04-01

428

Catalytic reduction of p-nitrophenol by using platinum nanoparticles stabilised by guar gum.  

PubMed

We report a facile and green method to synthesise highly stable dispersions of platinum nanoparticles (PtNPs) with an average particle size of ? 6 nm. Natural, nontoxic, eco-friendly biopolymer guar gum was utilised as both the reducing and capping agent precursor in aqueous medium. The PtNPs that had been stabilised by guar gum (GG-s-PtNPs) were characterised by UV-vis spectroscopy, XRD, TEM and XPS. GG-s-PtNPs performed better in terms of catalytic activity for the liquid phase reduction of p-nitrophenol (p-NP) compared to p-aminophenol (p-AP). The efficiency of the catalytic reduction of p-NP over GG-s-PtNPs was found to be 97% in a total time of 320 s at room temperature. The mechanisms of the synthesis and catalytic reduction of p-NP are also discussed. The synthesis approach presented here does not require stringent conditions or toxic agents and thus is a straightforward, rapid, efficient, and green approach to the fabrication of highly active catalysts. PMID:25256515

Pandey, Sadanand; Mishra, Shivani B

2014-11-26

429

Characterization of corn fiber gums from coarse and fine fiber and a study of their emulsifying properties  

Technology Transfer Automated Retrieval System (TEKTRAN)

The stabilities of orange oil emulsions stabilized with various concentrations of two different types of corn fiber gum (CFG-1 and 2) isolated from coarse (pericarp) and fine (endosperm) fiber from corn wet milling have been studied. CFG-1 and 2 were isolated from coarse and fine corn fiber by (a) ...

430

Graft [partially carboxymethylated guar gum-g-poly N-(hydroxymethyl) acrylamide] copolymer: from synthesis to applications.  

PubMed

Graft copolymer of N-(hydroxymethyl) acrylamide with carboxymethylated guar gum was synthesized and the reaction conditions were optimized for better yield using potassium peroxymonosulfate and thiourea as a redox initiator. The optimum reaction conditions for grafting have also been determined by studying the effect of N-(hydroxymethyl) acrylamide, hydrogen ion, peroxymonosulphate, thiourea concentration and carboxymethylated guar gum along with time and temperature. Experimental results show that maximum grafting has been obtained at 1.4 g dm(-3) concentration of carboxymethylated guar gum and 16×10(-2) mol dm(-3) concentration of N-(hydroxymethyl) acrylamide. It has been observed that grafting ratio, add on, conversion, efficiency and rate of grafting increase up to 6.0×10(-3) mol dm(-3) of hydrogen ion, 2.4×10(-3) mol dm(-3) of thiourea, 14×10(-3) mol dm(-3) of peroxymonosulphate and 35°C of temperature. Grafted copolymer has been characterized by FTIR spectroscopy and thermogravimetric analysis. Water swelling, flocculating, and metal ion uptake properties of partially carboxymethylated guar gum-g-N-(hydroxymethyl) acrylamide have been determined. PMID:24906757

Pandey, Vijay Shankar; Verma, Shiv Kumar; Behari, Kunj

2014-09-22

431

Production of galacto-manno-oligosaccharides from guar gum by beta-mannanase from Penicillium oxalicum SO.  

PubMed

Beta-mannanase from Penicillium oxalicum SO efficiently hydrolyzed guar galactomannan to galacto-manno-oligosaccharides. Gel filtration estimated the molecular weight of the beta-mannanase as 35 000 and SDS-PAGE as 29 000. The optimum pH was around 5 while a stable pH was reached in the range of 3-6. Optimum temperature was around 60 degrees C at pH 5, while under 60 degrees C activity was stable. HPLC analysis detected oligosaccharides with degrees of polymerization (DP) of 2 to 7 and 2 to 6 released on hydrolysis of guar and locust bean gums, respectively; about 92% of the released sugars were oligosaccharides. In analysis of the sugar distribution on MALDI-TOF-MS, major products of DP 6 and 7 and DP 5 and 6 were confirmed in hydrolysates of guar gum and locust bean gum, respectively. One of the main oligosaccharides released from guar gum, with DP 7, had a high galactose content (Gal/Man = 0.76) and corresponded to a blockwise galactose-substituted mannan type in galactomannan. PMID:17002466

Kurakake, Masahiro; Sumida, Takuya; Masuda, Daisuke; Oonishi, Saori; Komaki, Toshiaki

2006-10-01

432

Sensory and instrumental assessment of Chinese moon cake: Influences of almond flour, maltitol syrup, fat, and gums  

Microsoft Academic Search

The objectives of this research were to investigate sensory and instrumental (texture and color) quality attributes and their relation of newly formulated Chinese moon cakes: California almond flour and maltitol syrup were used as the replacement of wheat flour and sucrose syrup, respectively and gum was added as the fat-replacer. Sensory analysis showed that addition of almond flour had the

Chunli Jia; Yang Soo Kim; Weining Huang; Guangwei Huang

2008-01-01

433

Draft Genome Sequences of Four Bacillus thermoamylovorans Strains Isolated from Milk and Acacia Gum, a Food Ingredient  

PubMed Central

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

Krawczyk, Antonina O.; Berendsen, Erwin M.; Eijlander, Robyn T.; de Jong, Anne; Wells-Bennik, Marjon H. J.

2015-01-01

434

Glycaemic and insulin responses of diabetic patients to traditional Malaysian meals and the effect of guar gum.  

PubMed

The aims of the project were to determine the glycaemic and insulin responses of non-insulin dependent diabetic patients (NIDDM) to 3 traditional Malaysian meals compared to oral glucose, and to determine whether guar gum would affect these responses. Patients with NIDDM were tested with 75 g oral glucose and three common breakfast meals of the three main ethnic groups of Malaysia. When compared with the oral glucose group, significantly by lower blood glucose responses were seen at 90 and 120 minutes post prandial for nasi lemak (p<0.05) and at 60, 75 and 90 minutes for mee sup (p<0.05). No significant difference was seen for roti telur. There was no significant difference in plasma glucose at any time point of the study when the three test meals were compared with each other. Addition of 5g granulated guar gum mixed with water taken prior to the glucose significantly lowered the plasma glucose at 60, 120 and 150 minutes postprandially (p<0.05). Similarly for the test meals, guar gum significantly lowered plasma glucose concentration between 15 and 45 minutes (p<0.03) postprandial for nasi lemak and between 15 and 30 minutes (p<0.03) for mee sup but not with roti telur. With addition of guar gum, there was no significant change of insulin responses with the three meals but a significant increase was seen at 30 minutes (p<0.02) after ingestion of glucose. PMID:24394617

Khalid, B A; Lee, L F; Samad, A H; Ng, M L

1996-12-01

435

Effect of emulsifier and guar gum on micro structural, rheological and baking performance of frozen bread dough  

Microsoft Academic Search

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

P. D. Ribotta; G. T. Pérez; A. E. León; M. C. Añón

2004-01-01

436

Draft Genome Sequences of Four Bacillus thermoamylovorans Strains Isolated from Milk and Acacia Gum, a Food Ingredient.  

PubMed

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

Krawczyk, Antonina O; Berendsen, Erwin M; Eijlander, Robyn T; de Jong, Anne; Wells-Bennik, Marjon H J; Kuipers, Oscar P

2015-01-01

437

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

E-print Network

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 of follow up. Subjects, methods, and results We advertised among the general public asking for volunteers

Paris-Sud XI, Université de

438

Evaluation and Comparison of Changes in Microhardness of Primary and Permanent Enamel on Exposure to Acidic Center-filled Chewing Gum: An in vitro Study  

PubMed Central

ABSTRACT Objectives: The study is to evaluate changes in microhardness of enamel after exposure to acidic center filled chewing gum on primary and permanent teeth. Methods: Thirty primary and 30 permanent molar extracted teeth were painted with acid resistant varnish except a small window over buccal surface. Teeth were divided into four groups according to type of teeth and type of chewing gum (Center fresh and Bubbaloo) (D1, P1, D2 and P2); each tooth was exposed to whole chewing gum mashed with 5 ml of artificial saliva for five minutes at room temperature twice a day for 5 days. After the exposure, teeth were stored in deionized water and submitted for microhardness tests. Results: Paired t-test and independent sample t-test were used for statistical analysis. A significant reduction in microhardness was found between exposed and unexposed areas in all groups. There was no statistically significant difference in reduction of microhardness to chewing gums, and between primary and permanent enamel. Conclusion: There is a definite reduction in microhardness in all groups exposed to chewing gums. Both the chewing gums are equally erosive; both permanent and primary teeth were affected. How to cite this article: Mudumba VL, Muppa R, Srinivas NCH, Kumar DM. Evaluation and Comparison of Changes in Microhardness of Primary and Permanent Enamel on Exposure to Acidic Center-filled Chewing Gum: An in vitro Study. Int J Clin Pediatr Dent 2014;7(1):24-29. PMID:25206233

Muppa, Radhika; Srinivas, NCH; Kumar, Duddu Mahesh

2014-01-01

439

Land use and land cover classification, changes and analysis in gum Arabic belt in North Kordofan, Sudan  

NASA Astrophysics Data System (ADS)

The gum arabic belt in Sudan plays a significant role in environmental, social and economical aspects. This research was conducted in North Kordofan State, which is affected by modifications in conditions and composition of vegetation cover trends in the gum arabic belt as in the rest of the Sahelian Sudan zone. The objective of the paper is to study the classification, changes and analysis of the land use and land cover in the gum arabic belt in North Kordofan State in Sudan. The study used imageries from different satellites (Landsat and ASTER) and multi-temporal dates (MSS 1972, TM 1985, ETM+ 1999 and ASTER 2007) acquired in dry season. The imageries were geo-referenced and radiometrically corrected by using ENVI-FLAASH software. Image classification (pixel-based) and accuracy assessment were applied. Application of multi-temporal remote sensing data demonstrated successfully the identification and mapping of land use and land cover into five main classes. Forest dominated by Acacia senegal class was separated covering an area of 21% in the year 2007. The obvious changes and reciprocal conversions in the land use and land cover structure indicate the trends and conditions caused by the human interventions as well as ecological impacts on Acacia senegal trees. Also the study revealed that a drastic loss of forest resources occurred in the gum arabic belt in North Kordofan during 1972 to 2007 (25% for Acacia senegal trees). The study concluded that, using of traditional Acacia senegal-based agro-forestry as one of the most successful form in the gum belt.

Adam, Hassan E.; Csaplovics, Elmar; Elhaja, Mohamed E.; El Abbas, Mustafa M.

2013-10-01

440

Screening multimycotoxins in food-grade gums by stable isotope dilution and liquid chromatography/tandem mass spectrometry.  

PubMed

Stable isotope dilution with LC/MSIMS was used to determine the following 11 mycotoxins in food grade gums: aflatoxins B1, B2, G1, and G2; deoxynivalenol; fumonisins B1, B2, and B3; ochratoxin A; T-2 toxin; and zearalenone. Samples were fortified with 11 [13C]-uniformly labeled internal standard ([13C]-IS) mycotoxins that corresponded to the 11 target mycotoxins and extracted by acetonitrile-water (4 + 1, v/v), followed by LC/MS/MS analysis. Mycotoxins were quantitated with the fortified [13C]-IS in each sample. The average recoveries of aflatoxins B1, B2, G1, and G2 (1, 5, and 25 microg/kg); deoxynivalenol and fumonisins B1, B2, and B3 (25, 100, and 500 microg/kg); and ochratoxin A, T-2 toxin, and zearalenone (10, 50, and 250 microg/kg) ranged from 84 to 117% with RSDs less than 20%. Method-dependent LOQs were from 0.1 (aflatoxin B1) to 25 microg/kg (fumonisin B3). Among 20 market samples, aflatoxin B1 (< LOQ) was detected in a Guar gum and a Tragacanth gum, and zearalenone (6 +/- 0.6 microg/kg) was detected in a Xanthan gum. The detected mycotoxins were further confirmed by comparing their enhanced product ion spectra to those of reference standards. The single laboratory validated stable isotope dilution and LC/MSIMS method provides sufficient selectivity, sensitivity, accuracy, and reproducibility with a simple sample preparation to screen the 11 mycotoxins in gums. PMID:25051639

Zhang, Kai; Wong, Jon W; Jia, Zhengwei; Vaclavikova, Marta; Trucksess, Mary W; Begley, Timothy H

2014-01-01

441

Chewing Xylitol Gum Improves Self-Rated and Objective Indicators of Oral Health Status under Conditions Interrupting Regular Oral Hygiene.  

PubMed

Chewing xylitol gum provides oral health benefits including inhibiting Streptococcus mutans plaque. It is thought to be especially effective in conditions where it is difficult to perform daily oral cleaning. Our study aim was to determine the effects of chewing xylitol gum on self-rated and objective oral health status under a condition interfering with oral hygiene maintenance. A randomized controlled intervention trial was conducted on 55 healthy ? 20-year-old men recruited from the Japan Ground Self Defense Force who were undergoing field training. Participants were randomly assigned to a test group (chewing gum; n = 27) or a control group (no gum; n = 28) and the researchers were blinded to the group assignments. The Visual Analog Scale (VAS) scores of oral conditions subjectively evaluated oral health, and the stimulated salivary bacteria quantity objectively evaluated oral health 1 day before field training (baseline) and 4 days after the beginning of field training (follow-up). VAS scores of all three oral conditions significantly increased in the control group (malodor: p < 0.001; discomfort: p < 0.001; dryness: p < 0.001), but only two VAS scores increased in the test group (malodor: p = 0.021; discomfort: p = 0.002). The number of salivary total bacteria significantly increased in the control group (p < 0.01), while no significant change was observed in the test group (p = 0.668). Chewing xylitol gum positively affects self-rated and objective oral health status by controlling oral hygiene under conditions that interfere with oral hygiene maintenance. PMID:25744362

Hashiba, Takafumi; Takeuchi, Kenji; Shimazaki, Yoshihiro; Takeshita, Toru; Yamashita, Yoshihisa

2015-01-01

442

A facile synthesis and characterization of Ag, Au and Pt nanoparticles using a natural hydrocolloid gum kondagogu (Cochlospermum gossypium).  

PubMed

An environmentally benign method for the synthesis of noble metal nanoparticles has been reported using aqueous solution of gum kondagogu (Cochlospermum gossypium). Both the synthesis, as well as stabilization of colloidal Ag, Au and Pt nanoparticles has been accomplished in an aqueous medium containing gum kondagogu. The colloidal suspensions so obtained were found to be highly stable for prolonged period, without undergoing any oxidation. SEM-EDXA, UV-vis spectroscopy, XRD, FTIR and TEM techniques were used to characterize the Ag, Au and Pt nanoparticles. FTIR analysis indicates that -OH groups present in the gum matrix were responsible for the reduction of metal cations into nanoparticles. UV-vis studies showed a distinct surface plasmon resonance at 412 and 525 nm due to the formation of Au and Ag nanoparticles, respectively, within the gum network. XRD studies indicated that the nanoparticles were crystalline in nature with face centered cubic geometry. The noble metal nanoparticles prepared in the present study appears to be homogeneous with the particle size ranging between 2 and 10 nm, as evidenced by TEM analysis. The Ag and Au nanoparticles formed were in the average size range of 5.5±2.5 nm and 7.8±2.3 nm; while Pt nanoparticles were in the size range of 2.4±0.7 nm, which were considerably smaller than Ag and Au nanoparticles. The present approach exemplifies a totally green synthesis using the plant derived natural product (gum kondagogu) for the production of noble metal nanoparticles and the process can also be extended to the synthesis of other metal oxide nanoparticles. PMID:21185161

Vinod, V T P; Saravanan, P; Sreedhar, B; Devi, D Keerthi; Sashidhar, R B

2011-04-01

443

Chewing gums has stimulatory effects on bowel function in patients undergoing cesarean section: A randomized controlled trial  

PubMed Central

The aim of study was to investigate the effect of postoperative gum chewing on the recovery of bowel function after cesarean section. Total 100 women delivered by lower uterine segment section cesarean under local anesthesia (spinal). Eligible patients were randomly allocated into two groups: a gum-chewing group (n=50) or a control group (n= 50). The gum-chewing group participants who received one stick of sugarless gum for one hours, three times daily immediately after recovery from anesthesia and the control group had the usual postoperative care until being discharged. All women were followed up regularly until discharge from hospital, and recorded the times to the first bowel sounds of normal intestinal sounds, the time to the first passage of flatus, the time to the first feeling of hunger, and the time to the first defecation. The operative data, postoperative tolerance of gum chewing, and postoperative complications were documented. There was no statistically significant difference between the two groups in terms of demographic characteristics such as age, body mass index, parity, duration of surgery, number of miscarriages and curettages, time to the first feeding, the amount of serum intake, and type of cesarean section. The mean average postoperative interval of the first bowel sounds (21.9 versus 26.1 hours, p= 0.016), the first feeling of hunger (11.8 versus 14.5 hours, p= 0.050), the first passage of flatus (24.8 versus 30.0 hours, P=0.002), the first defecation (30.6 versus 38.4 hours, P= 0.0001) was significantly shorter compared to the control group. PMID:23198943

Ledari, Farideh Mohsenzadeh; Barat, Shanaz; Delavar, Mouloud Agajani

2012-01-01

444

Bleeding Gums  

MedlinePLUS

... use . Home Symptom Checkup Injury Checkup Disease Checkup Women's Checkup Pregnancy Checkup Baby Checkup Mens Checkup Stephen J. Schueler, M.D. About Stephen J. Schueler, MD How it Works Testimonials FAQ for Consumers FAQ for Physicians News Advertising Terms of Use Contact Us Site Map How ...

445

Gums - swollen  

MedlinePLUS

... by a virus or fungus Malnutrition Poorly fitting dentures or other dental appliances Pregnancy Sensitivity to toothpaste ... was the last time you had a professional cleaning? Have there been any changes to your diet? ...

446

Ideal tensile and shear strength of a gum metal approximant: Ab initio density functional calculations  

NASA Astrophysics Data System (ADS)

The ideal tensile and shear strengths of binary ?-phase Ti3Nb alloys have been investigated using ab initio density functional calculations. The binary alloy is considered as an approximant to the multifunctional Ti-Nb-Ta-Zr-O alloy known as “gum metal,” which displays high strength, low elastic modulus, high yield strain, and very good ductility. This alloy has been reported to deform elastically until the stress approaches the ideal tensile strength. Our calculations have been performed for an optimized chemical decoration of the body-centered cubic (bcc) structure of the ? phase. Previous work has demonstrated that this model yields elastic constants in very good agreement with those measured for gum metal specimens and leads to a reasonably accurate description of the martensitic transformations between the bcc ?, the orthorhombic ?'' and the hexagonal ? phases [Lazar , Phys. Rev. BPLRBAQ0556-280510.1103/PhysRevB.84.054202 84, 054202 (2011)]. The simulations of the response to tensile and shear loading have been performed for large supercells which account also for the different orientations of the -Nb-Nb- chains characteristic for the ?-phase structure relative to the direction of the applied load. The energy-strain and stress-strain curves are found to be very different from those reported for all bcc metals. Under uniaxial <100> loading we find an ideal tensile strength of 2.4 GPa, the upper limit to the tensile stress arising from a shear instability of the structure. Under uniaxial <110> load we calculate an ideal tensile strength of 2.2 or 2.8 GPa, depending on the orientation of the -Nb-Nb- chains relative to the loading direction. For a realistic multidomain structure the ideal strength is expected to correspond to the average of these values. An ideal strength of 2.6 GPa under <110> loading is roughly the same as under <100> load, despite a considerable anisotropy of the tensile moduli. For {211}<111> shear we calculate an ideal shear strength of 1.6 GPa, again as an average over different possible shearing directions relative to the Nb-Nb bonds. For the {110}<110> shear system we find a lower strength of 0.9 GPa. The structures reached at the stress maximum under <100> uniaxial tension and {211}<111> shear are identical, and since the maximal shear stress is much lower than the tensile stress, the alloy will fail by shear even under strictly uniaxial tension. The values of the ideal tensile and shear strengths are significantly low, even in comparison with those calculated for bcc V and Nb with very small shear moduli and approach the values reported for gum metal alloys.

Nagasako, Naoyuki; Asahi, Ryoji; Hafner, Jürgen

2012-01-01

447

Functions of gum arabic and soybean soluble polysaccharide in cooked rice as a texture modifier.  

PubMed

The textural properties of cooked rice were investigated in the presence and the absence of gum arabic (GA) and soybean soluble polysaccharide (SSPS). SSPS was more effective in increasing the hardness and in decreasing the stickiness of the rice grains than GA. For both polysaccharides, the increase in hardness was more apparent in the whole body than at the periphery, whereas the decrease in stickiness was more apparent at the periphery than in the whole body. SSPS was more effective in retarding the gelatinization of rice starch and in lowering the elastic characters of the glutinous layer (the materials leached out of the rice grains during cooking) along with a decrease in the amount of amylopectin leached. The textural hardness of cooked rice was determined by the degree of starch gelatinization, whereas the textural stickiness was related to the rheological characters of the glutinous layer and the leaching profile of the starch components. PMID:20057116

Ishihara, Sayaka; Nakauma, Makoto; Funami, Takahiro; Nakaura, Yoshiko; Inouchi, Naoyoshi; Nishinari, Katsuyoshi

2010-01-01

448

Preparation and properties of organic-inorganic composite superabsorbent based on xanthan gum and loess.  

PubMed

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

Feng, Enke; Ma, Guofu; Wu, Yajuan; Wang, Haiping; Lei, Ziqiang

2014-10-13

449

Tests for mutagenic effects of ammoniated glycyrrhizin, butylated hydroxytoluene, and gum arabic in roden germ cells  

SciTech Connect

Ammoniated glycyrrhizin, butylated hydroxytoluene, and gum Arabic are generally recognized as safe (GRAS) substances that are used primarily as additives in foods. These substances were incorporated into rodent diets and fed to male rats and mice for 10 and 8 wk, respectively. The treated male mice and rats were then tested for dominant lethal effects. The mice were also tested for induced heritable translocation. Results of the rat studies indicated a statistically significant dominant lethal effect of each of the compounds tested; however, the biological significance of this response is not known. Results of the mouse dominant lethal and heritable translocation studies, on the other hand, indicated no adverse effects of the compounds tested.

Sheu, C.W.; Cain, K.T.; Rushbrook, C.J.; Jorgenson, T.A.; Generoso, W.M.

1986-01-01

450

Effect of ionic crosslink on the release of metronidazole from partially carboxymethylated guar gum tablet.  

PubMed

Partially carboxymethylated guar gum (PCMGG) was crosslinked in situ by Ca(2+) ions during wet massing step of tablet preparation. The resulting tablets were evaluated for the effect of the extent of crosslinking on drug release and matrix swelling. Increase in the concentration of Ca(2+) ions increased the viscosity of gel layer and reduced the water penetration velocity into the matrix with subsequent decrease in swelling of the tablets and drug release. Beyond a certain concentration of Ca(2+) ions, the viscosity of the gel layer decreased and the drug release rate increased primarily due to erosion of the matrix. The mechanism of drug release appeared to be non-Fickian or anomalous transport. The release data also best fitted in zero order equation. The model drug, metronidazole, was compatible with the matrix materials as evident from instrumental analyses. Such formulation may provide flexibility in achieving the desired drug release rate from crosslinked matrix tablets. PMID:24721097

Singh, Rakesh; Maity, Siddhartha; Sa, Biswanath

2014-06-15

451

Polyelectrolytic aqueous guar gum for adsorptive separation of soluble Pb(II) from contaminated water.  

PubMed

The article introduces the concept of homophase adsorption of soluble Pb(II) from contaminated water using aqueous guar gum (GG). The process appears to be extremely handy since it avoids hectic sample preparation and adsorbent recovery stages. The results show that, addition of only 1000 ppm GG removes 56.72% of the contaminated Pb(II) within 150 min at 303 K. The best working pH has been found to be at 4.5. At this point GG molecules show greatest balance between negative zeta potential and high molecular size. Mechanistically, the adsorption follows Langmuir model since on formation of a monolayer, the positive Pb(II) prevent subsequent adsorption through strong electrostatic repulsion. The adsorption kinetics follows pseudo second order model. Both kinetics and thermodynamics of the process complies with the conventional hetero facial adsorption models despite huge procedural differences. PMID:24906750

Pal, Abhijit; Nasim, Tanbir; Giri, Arindam; Bandyopadhyay, Abhijit

2014-09-22

452

Semi-dilute galactomannan solutions: observations on viscosity scaling behavior of guar gum.  

PubMed

Based on experimental work involving evaluation of viscosity enhancement of aqueous solutions by high molecular weight guar gum, we have observed that the shear viscosity scaling exponent b for semi-dilute solutions, ?sp ~ (c[?])(b), is sensitive to molecular weight, being approximately 4.7 for native samples and decreasing progressively as Mw is lowered. The critical overlap parameter demarcating the dilute and semi-dilute regimes also depends on the molecular weight as (c[?])* ~Mw(-0.82). Consequently, viscosity-concentration plots fail to achieve overlap using only specific viscosity and overlap concentration as reducing variables, a commonly accepted empiricism for random-coil polysaccharides. To bridge the gap, we propose to account for water solubility, its temperature dependence and the resulting chain flexibility as additional factors to fully describe the solution behavior of these highly-important raw materials. PMID:25347591

Pollard, Michael A; Fischer, Peter

2014-11-19

453

Preparation and characterization of guar gum hydrogels as carrier materials for controlled protein drug delivery.  

PubMed

Hydrogels were prepared from guar gum (GG) via esterification with 1,2,3,4-butanetetracarboxylic dianhydride (BTCA). Detailed spectroscopic analysis using FTIR and solid-state NMR revealed that an increase in the BTCA feed amount in the preparation mixture led to an increased degree of crosslinking, which affected the swelling behavior and rheological properties of the hydrogels. The hydrogels exhibited enzyme degradability, and after incubation with ?-mannanase and ?-galactosidase, 30-57% of the hydrogels were degraded. In addition, the hydrogels adsorbed bovine serum albumin and hen egg white lysozyme thorough electrostatic and hydrophobic interactions. The protein-adsorbed GG hydrogels exhibited a slow and steady release of the proteins over a 24h period in buffer solutions after a fast release of proteins in the first hour. As such, GG hydrogels are expected to be efficient drug delivery carriers for protein-based drugs. PMID:25037422

Kono, Hiroyuki; Otaka, Fumihiro; Ozaki, Masato

2014-10-13

454

In situ generation of silver nanoparticles within crosslinked 3D guar gum networks for catalytic reduction.  

PubMed

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

Zheng, Yian; Zhu, Yongfeng; Tian, Guangyan; Wang, Aiqin

2015-02-01

455

Semi-dilute galactomannan solutions: observations on viscosity scaling behavior of guar gum  

NASA Astrophysics Data System (ADS)

Based on experimental work involving evaluation of viscosity enhancement of aqueous solutions by high molecular weight guar gum, we have observed that the shear viscosity scaling exponent b for semi-dilute solutions, ?sp ˜ (c[?])b, is sensitive to molecular weight, being approximately 4.7 for native samples and decreasing progressively as Mw is lowered. The critical overlap parameter demarcating the dilute and semi-dilute regimes also depends on the molecular weight as {{?ft(c[? ]\\right)}*} ˜ Mw-0.82 . Consequently, viscosity–concentration plots fail to achieve overlap using only specific viscosity and overlap concentration as reducing variables, a commonly accepted empiricism for random-coil polysaccharides. To bridge the gap, we propose to account for water solubility, its temperature dependence and the resulting chain flexibility as additional factors to fully describe the solution behavior of these highly-important raw materials.

Pollard, Michael A.; Fischer, Peter

2014-11-01

456

Uniquely different PVA-xanthan gum irradiated membranes as transdermal diltiazem delivery device.  

PubMed

This paper reports interesting differences between physical and mechanical properties of various membranes prepared from high and low molecular weight poly (vinyl alcohol) (PVA) and xanthan gum (XG) blends irradiated under low dose electron beam. The membranes were designed for sustained delivery of diltiazem hydrochloride through skin. Electron beam irradiation produced crosslinks and turned PVA into crystalline phase from its amorphous organization in the unirradiated state. PVA crystals were fibrillar at low XG content (1 wt.%) when the molecular weight was high while similar orientation at higher XG content (5 wt.%) when the molecular weight was low. Low molecular weight PVA-XG membranes showed equivalent physical properties under dry condition but wet-mechanical properties were superior for high molecular weight PVA-XG hybrids. Both of them showed slow and sustained diltiazem release but the later induced slightly slower release despite low drug encapsulation efficiency due to its better wet mechanical strength. PMID:23618267

Bhunia, Tridib; Giri, Arindam; Nasim, Tanbir; Chattopadhyay, Dipankar; Bandyopadhyay, Abhijit

2013-06-01

457

Electrochemical biosensor for catechol using agarose-guar gum entrapped tyrosinase.  

PubMed

An electrochemical biosensor using tyrosinase was constructed for the determination of catechol. The enzyme was extracted from a plant source Amorphophallus companulatus and entrapped in agarose-guar gum composite biopolymer matrix. Catechol was determined by direct reduction of biocatalytically liberated quinone species at -0.1 V versus Ag/AgCl (3M KCl). The response was found to be linear and concentration dependent in the range of 6 x 10(-5) to 8 x 10(-4)M with a lower detection limit of 6 microM. It has reusability up to 20 cycles and a shelf life of more than 2 months when stored at 4 degrees C. PMID:17113674

Tembe, Sanket; Inamdar, Shaukat; Haram, Santosh; Karve, Meena; D'Souza, S F

2007-01-30

458

Biodistribution of maltose and gum arabic hybrid gold nanoparticles after intravenous injection in juvenile swine.  

PubMed

This article describes several experiments performed to test our hypothesis that the agent used to coat/stabilize gold nanoparticles (AuNPs) will act to direct the AuNPs to specific tissues within the body and that changing the coating will change the target organ. Samples were also collected for pathological examination. Gum arabic- (GA) and maltose- (MALT) stabilized AuNPs were administered intravenously to juvenile swine, and blood, tissue, and urine samples were collected for gold analysis. Our results indicate that differences do exist between the two NP constructs tested, with 50% or greater of the total gold dose being found in the liver or lung for the GA- and MALT-stabilized AuNPs, respectively. These findings indicate that the functional unit used to coat/stabilize the AuNPs has an important role in determining the tissue distribution profile for individual AuNP constructs. PMID:19480048

Fent, Genevieve M; Casteel, Stan W; Kim, Dae Young; Kannan, Raghuraman; Katti, Kavita; Chanda, Nripen; Katti, Kattesh

2009-06-01

459

Phase separation induced molecular fractionation of gum arabic--sugar beet pectin systems.  

PubMed

This paper investigates the phase separation and phase separation-induced fractionation of gum arabic (GA)/sugar beet pectin (SBP) mixed solutions. A phase diagram, including cloud and binodal curves, was established by visual observation and phase composition analysis. The deviation of the binodal curve from the cloud curve was a result of phase separation-induced fractionation of polydisperse GA and SBP molecules. Fractionation of GA increased the content of arabinogalactan-protein complex (AGP) from ca. 13% to 27%. The fractionated GA (FGA) showed improved emulsifying functionality, whereas the fractionated SBP (FSBP) had a reduced emulsifying functionality. The changes in emulsifying efficiency can be explained by interfacial adsorption behaviors at the oil-water interface as indicated by interfacial tension measurements. PMID:23987401

Mao, Peng; Zhao, Meng; Zhang, Fan; Fang, Yapeng; Phillips, Glyn O; Nishinari, Katsuyoshi; Jiang, Fatang

2013-10-15

460

Effect of okra gum on the pasting, thermal, and viscous properties of rice and sorghum starches.  

PubMed

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 C