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1

Preparation and Evaluation of Soft Gellan Gum Gel Containing Paracetamol  

PubMed Central

The objective of this study was to develop soft paracetamol gel using gellan gum as a gelling agent and sodium citrate as a source of cation. Different batches were prepared using three different concentrations of gellan gum (0.1, 0.3, and 0.5%), each with two different sodium citrate concentrations (0.3 and 0.5%). The consistency of the paracetamol gel was dependent on the concentration of gellan gum, sodium citrate and co-solute. The results of dissolution study of soft gel containing 0.3% gellan gum and 0.3% sodium citrate revealed that paracetamol was completely released in 30 min. Polyethylene glycol 400 worked as a solubilizer for paracetamol. All the gels possessed acceptable sensory characteristics when evaluated by human volunteers. Short term stability study carried out for four weeks at different temperatures revealed no considerable changes in performance characteristics of developed optimized formulation. PMID:20336205

Gohel, M. C.; Parikh, R. K.; Nagori, S. A.; Shah, S. N.; Dabhi, M. R.

2009-01-01

2

Rheology and microrheology of a microstructured fluid: The gellan gum case  

E-print Network

Rheology and microrheology of a microstructured fluid: The gellan gum case M. Caggionia) Department the effect of a constant applied shear during gelation of aqueous gellan gum with a monovalent salt. Shear modifies the gellan gum hydrogel microstructure and the bulk rheological properties of the system

Blair, Daniel

3

Sensory quality of low-sugar orange gels with gellan, xanthan and locust bean gums  

Microsoft Academic Search

Effects of reducing the sucrose content (from 55 to 30?°Brix in the final product) and of the use of gellan gum or a mixture of gellan, xanthan and locust bean gums (3:1:1) on the\\u000a mechanical characteristics (maximum rupture force and deformation at rupture) of orange gels prepared with 15%?w\\/w fruit pulp,\\u000a sucrose and different amounts of hydrocolloids (0.25, 0.4, 0.55

M. H. Damásio; E. Costell; Luis Durán

1997-01-01

4

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

5

Influence of fermentation hydrodynamics on gellan gum physico-chemical characteristics  

Microsoft Academic Search

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

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

1996-01-01

6

Gellan gum-g-N-vinyl-2-pyrrolidone: Synthesis, swelling, metal ion uptake and flocculation behavior.  

PubMed

The synthesis of graft copolymer (gellan gum-g-N-vinyl-2-pyrrolidone) is carried out in nitrogen atmosphere using potassium bromate and silver as redox system. The reaction conditions for maximum grafting have been optimized by varying the reaction variables, including the concentration of N-vinyl-2-pyrrolidone (12.0×10(--2) to 28×10(--2)moldm(-3)), potassium bromate (6×10(-3) to 22×10(-3)moldm(-3)), silver (2.4×10(-3)to 5.6×10(-3)moldm(-3)), sulphuric acid (2.0×10(-3) to 10×10(-3)moldm(-3)), gellan gum (0.6-1.4gdm(-3)) along with time duration (60 to 180min) and temperature (30-50°C).Water swelling capacity, metal ion sorption and flocculation studies of synthesized graft copolymer have been performed with respect to the parent polymer. The graft copolymer has been characterized by FTIR spectroscopy and thermogravimetric analysis. PMID:25450548

Verma, Shiv Kumar; Pandey, Vijay Shankar; Behari, Mithilesh Yadav Kunj

2015-01-01

7

Biological performance of cell-encapsulated methacrylated gellan gum-based hydrogels for nucleus pulposus regeneration.  

PubMed

Limitations of current treatments for intervertebral disc (IVD) degeneration have promoted interest in the development of tissue-engineering approaches. Injectable hydrogels loaded with cells can be used as a substitute material for the inner IVD part, the nucleus pulposus (NP), and provide an opportunity for minimally invasive treatment of IVD degeneration. The NP is populated by chondrocyte-like cells; therefore, chondrocytes and mesenchymal stem cells (MSCs), stimulated to differentiate along the chondrogenic lineage, could be used to promote NP regeneration. In this study, the in vitro and in vivo response of human bone marrow-derived MSCs and nasal chondrocytes (NCs) to modified gellan gum-based hydrogels was investigated. Both ionic- (iGG-MA) and photo-crosslinked (phGG-MA) methacrylated gellan gum hydrogels show no cytotoxicity in extraction assays with MSCs and NCs. Furthermore, the materials do not induce pro-inflammatory responses in endothelial cells. Moreover, MSCs and NCs can be encapsulated into the hydrogels and remain viable for at least 2 weeks, although apoptosis is observed in phGG-MA. Importantly, encapsulated MSCs and NCs show signs of in vivo chondrogenesis in a subcutaneous implantation of iGG-MA. Altogether, the data endorse the potential use of modified gellan gum-based hydrogel as a suitable material in NP tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd. PMID:25370800

Tsaryk, Roman; Silva-Correia, Joana; Oliveira, Joaquim Miguel; Unger, Ronald E; Landes, Constantin; Brochhausen, Christoph; Ghanaati, Shahram; Reis, Rui L; Kirkpatrick, C James

2014-11-01

8

Studies on graft copolymerization of gellan gum with N,N-dimethylacrylamide by the redox system.  

PubMed

The present paper reports the graft copolymerization of N,N-dimethylacrylamide onto gellan gumby free radical polymerization using potassium peroxymonosulphate/sarbose redox system in an inert atmosphere. The reaction conditions for maximum grafting have been optimized by varying the reaction variables, including the concentration of N,N-dimethylacrylamide(4.0×10(-2)-20×10(-2) mol dm(-3)), potassium peroxymonosulphate (0.6×10(-2)-1.4×10(-2)mol dm(-3)), sarbose (0.4×10(-3)-3.6×10(-3) mol dm(-3)), sulphuric acid (2.0×10(-3)-10×10(-3) mol dm(-3)), gellan gum (0.6-1.4 g dm(-3)) along with time duration (60-180 min) and temperature (25-45°C).Water-swelling capacity, metal ion sorption and flocculation studies of synthesized graft copolymer have been performed with respect to the parent polymer. The graft copolymer has been characterized by FTIR spectroscopy and thermogravimetric analysis. PMID:24984020

Pandey, Vijay Shankar; Verma, Shiv Kumar; Yadav, Mithilesh; Behari, Kunj

2014-09-01

9

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

Microsoft Academic Search

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

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

2011-01-01

10

Gellan gum based microparticles of metoclopromide hydrochloride for intranasal delivery: development and evaluation.  

PubMed

The purpose of this study was to develop nasal microparticles of metoclopromide employing gellan gum as a polymer by spray drying method. This method of microencapsulation is particularly less dependent on the solubility characteristics of the drug and polymer and is simple, reproducible, and easy to scale up. The microparticles were evaluated for characteristics like particle size, incorporation efficiency, swelling ability, zeta potential, mucoadhesion, thermal analysis, X-ray diffraction (XRD) study and in vitro drug release. The microparticles so prepared had irregular shape and smooth but distorted surface morphology. They were negatively charged. The particle size ranged from 9.38 to 10.67 microm. Differential scanning calorimetry (DSC) studies revealed that metoclopromide was molecularly dispersed inside the microparticles. The swelling was increased with increase in amount of polymer. The release of drug from microparticles was moderately sustained without lag time and attributed to formation of hydrogel; ionically cross linked hydrogel was hypothesized. The formulation was found to be non toxic to nasal tissue. These in vitro preliminary results show that spray dried microparticles based on gellan gum could be suitable nasal delivery system for the administration of metoclopromide. PMID:19336933

Mahajan, Hitendra Shaligram; Gattani, Surendra Ganeshlal

2009-04-01

11

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

12

Aceclofenac-loaded unsaturated esterified alginate/gellan gum microspheres: in vitro and in vivo assessment.  

PubMed

Aceclofenac-loaded alginate/gellan gum microspheres for prolonged aceclofenac release were prepared through maleic anhydride-induced unsaturated esterification. The drug entrapment efficiency of these microspheres was found 39.30 ± 1.28% to 98.46 ± 0.40% and their average particle sizes were 270-490 ?m. These microspheres were characterized by FTIR, DSC, P-XRD and SEM analysis. The in vitro dissolution indicated prolonged sustained release of aceclofenac over 6h, which also followed the Korsmeyer-Peppas model (R(2)=0.9571-0.9952). The microspheres prepared through 3% (w/v) maleic anhydride-induced esterification exhibited comparatively slower drug-release. Most of the microspheres were followed Fickian diffusion mechanism except the microspheres containing higher gellan gum content, which followed anomalous (non-Fickian) diffusion. The in vivo results showed sustained systemic absorption of aceclofenac in rabbits and excellent anti-inflammatory activity in carrageenan-induced rats after oral administration over prolonged period. PMID:23499517

Jana, Sougata; Das, Arindam; Nayak, Amit Kumar; Sen, Kalyan Kumar; Basu, Sanat Kumar

2013-06-01

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

High rate of N2 fixation by East Siberian cryophilic soil bacteria as determined by measuring acetylene reduction in nitrogen-poor medium solidified with gellan gum.  

PubMed

For evaluating N(2) fixation of diazotrophic bacteria, nitrogen-poor liquid media supplemented with at least 0.5% sugar and 0.2% agar are widely used for acetylene reduction assays. In such a soft gel medium, however, many N(2)-fixing soil bacteria generally show only trace acetylene reduction activity. Here, we report that use of a N(2) fixation medium solidified with gellan gum instead of agar promoted growth of some gellan-preferring soil bacteria. In a soft gel medium solidified with 0.3% gellan gum under appropriate culture conditions, bacterial microbiota from boreal forest bed soils and some free-living N(2)-fixing soil bacteria isolated from the microbiota exhibited 10- to 200-fold-higher acetylene reduction than those cultured in 0.2% agar medium. To determine the N(2) fixation-activating mechanism of gellan gum medium, qualitative differences in the colony-forming bacterial components from tested soil microbiota were investigated in plate cultures solidified with either agar or gellan gum for use with modified Winogradsky's medium. On 1.5% agar plates, apparently cryophilic bacterial microbiota showed strictly distinguishable microbiota according to the depth of soil in samples from an eastern Siberian Taiga forest bed. Some pure cultures of proteobacteria, such as Pseudomonas fluorescens and Burkholderia xenovorans, showed remarkable acetylene reduction. On plates solidified with 1.0% gellan gum, some soil bacteria, including Luteibacter sp., Janthinobacterium sp., Paenibacillus sp., and Arthrobacter sp., uniquely grew that had not grown in the presence of the same inoculants on agar plates. In contrast, Pseudomonas spp. and Burkholderia spp. were apparent only as minor colonies on the gellan gum plates. Moreover, only gellan gum plates allowed some bacteria, particularly those isolated from the shallow organic soil layer, to actively swarm. In consequence, gellan gum is a useful gel matrix to bring out growth potential capabilities of many soil diazotrophs and their consortia in communities of soil bacteria. PMID:19286791

Hara, Shintaro; Hashidoko, Yasuyuki; Desyatkin, Roman V; Hatano, Ryusuke; Tahara, Satoshi

2009-05-01

15

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

PubMed

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

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

2013-06-01

16

Preparation of polymer gel dosimeters based on less toxic monomers and gellan gum  

NASA Astrophysics Data System (ADS)

New polymer gel dosimeters consisting of 2-hydroxyethyl methacrylate (HEMA), triethylene glycol monoethyl ether monomethacrylate (TGMEMA), polyethylene glycol 400 dimethacrylate (9G), tetrakis (hydroxymethyl) phosphonium chloride as an antioxidant, and gellan gum as a gel matrix were prepared. They were optically analyzed by measuring absorbance to evaluate a dose response. The absorbance of the polymer gel dosimeters that were exposed to 60Co ?-rays increased with increasing dose. The dosimeters comprising HEMA and 9G showed a linear increase in absorbance in the dose range from 0 to 10 Gy. The dose response depended on the 9G concentration. For others comprising HEMA, 9G and TGMEMA, the absorbance of the polymer gel dosimeters drastically increased above a certain dose, and then leveled off up to 10 Gy. The optical variations in these polymer gel dosimeters were also induced by x-irradiation from Cyberknife radiotherapy equipment. Furthermore, the exposed region of the latter polymer gel dosimeter exhibited a thermo-responsive behavior.

Hiroki, A.; Sato, Y.; Nagasawa, N.; Ohta, A.; Seito, H.; Yamabayashi, H.; Yamamoto, T.; Taguchi, M.; Tamada, M.; Kojima, T.

2013-10-01

17

Gellan gum-based hydrogels for intervertebral disc tissue-engineering applications  

Microsoft Academic Search

Intervertebral disc (IVD) degeneration is a challenging clinical problem\\u000d\\u000a that urgently demands viable nucleus pulposus (NP) implant materials.\\u000d\\u000a The best suited biomaterial for NP regeneration has yet to be\\u000d\\u000a identified, but it is believed that biodegradable hydrogel-based\\u000d\\u000a materials are promising candidates. In this work, we have developed\\u000d\\u000a ionic-and photo-crosslinked methacrylated gellan gum (GG-MA) hydrogels\\u000d\\u000a to be used in acellular and

J. Silva-Correia; J. M. Oliveira; S. G. Caridade; J. T. Oliveira; R. A. Sousa; J. F. Mano; R. L. Reis

2011-01-01

18

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

PubMed

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. PMID:21069248

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

2011-02-01

19

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

20

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

21

Development of Gellan Gum-Based Microparticles\\/Hydrogel Matrices for Application in the Intervertebral Disc Regeneration  

Microsoft Academic Search

Low back pain is one of the most reported medical conditions associated\\u000d\\u000a to intervertebral disc (IVD) degeneration. Nucleus pulposus (NP) is\\u000d\\u000a often regarded as the structure where IVD degeneration begins. Gellan\\u000d\\u000a gum (GG)-based hydrogels for acellular and cellular tissue engineering\\u000d\\u000a strategies have been developed for finding applications as NP\\u000d\\u000a substitutes. The innovative strategy is based on the reinforcement of\\u000d\\u000a the

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

2011-01-01

22

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

23

Gellan gum biosynthesis in Sphingomonas paucimobilis ATCC 31461: Genes, enzymes and exopolysaccharide production engineering  

Microsoft Academic Search

  The commercial gelling agent, gellan, is an extracellular polysaccharide (EPS) produced by Sphingomonas paucimobilis ATCC 31461. In recent years, significant progress in understanding the relationship between gellan structure and properties\\u000a and elucidation of the biosynthesis and engineering of this recent product of biotechnology has been made. This review focuses\\u000a on recent advances in this field. Emphasis is given to identification

I Sá-Correia; A M Fialho; P Videira; L M Moreira; A R Marques; H Albano

2002-01-01

24

Injectable and photocross-linkable gels based on gellan gum methacrylate: A new tool for biomedical application.  

PubMed

In this work, a natural polysaccharide gellan gum (GG) has been modified with methacrylic groups (GG-MA) and combined with polyethylene glycol dimethacrylate (PEG-DMA) in order to create novel injectable hydrogels that can be easily delivered through a needle and photocross-linked in the injection site. A novel synthetic procedure for methacrylation of GG has been proposed to better control its derivatization. Different degrees of functionalization have been achieved and their effects on the solubility and mechanical properties of GG-MA were investigated. A good balance in terms of hydrophilicity and elasticity of the corresponding hydrogels was identified, although not suitable enough as injectable material for the treatment of damaged soft tissues. For this reason, several concentrations and different molecular weights of PEG-DMA were investigated to modulate the composition of GG-MA hydrogels and overcome their extreme fragility. Swelling abilities of the hydrogels in different media were studied as a key parameter able to affect the release profile of loaded therapeutic agents. Model molecules having different spherical hindrance (sulindac and vitamin B12) were then chosen to study how the hydrogels were able to modulate their diffusion profiles over time. Finally, the hydrogel's safety was evaluated trough an MTT cytotoxicity test on human fibroblasts. PMID:25450552

Pacelli, Settimio; Paolicelli, Patrizia; Dreesen, Inge; Kobayashi, Shuichiro; Vitalone, Annabella; Casadei, Maria Antonietta

2015-01-01

25

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

PubMed

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

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

2013-12-01

26

Gellan gum-hyaluronic acid spongy-like hydrogels and cells from adipose tissue synergize promoting neoskin vascularization.  

PubMed

Currently available substitutes for skin wound healing often result in the formation of nonfunctional neotissue. Thus, urgent care is still needed to promote an effective and complete regeneration. To meet this need, we proposed the assembling of a construct that takes advantage of cell-adhesive gellan gum-hyaluronic acid (GG-HA) spongy-like hydrogels and a powerful cell-machinery obtained from adipose tissue, human adipose stem cells (hASCs), and microvascular endothelial cells (hAMECs). In addition to a cell-adhesive character, GG-HA spongy-like hydrogels overpass limitations of traditional hydrogels, such as reduced physical stability and limited manipulation, due to improved microstructural arrangement characterized by pore wall thickening and increased mean pore size. The proposed constructs combining cellular mediators of the healing process within the spongy-like hydrogels that intend to recapitulate skin matrix aim to promote neoskin vascularization. Stable and off-the-shelf dried GG-HA polymeric networks, rapidly rehydrated at the time of cell seeding then depicting features of both sponges and hydrogels, enabled the natural cell entrapment/encapsulation and attachment supported by cell-polymer interactions. Upon transplantation into mice full-thickness excisional wounds, GG-HA spongy-like hydrogels absorbed the early inflammatory cell infiltrate and led to the formation of a dense granulation tissue. Consequently, spongy-like hydrogel degradation was observed, and progressive wound closure, re-epithelialization, and matrix remodelling was improved in relation to the control condition. More importantly, GG-HA spongy-like hydrogels promoted a superior neovascularization, which was enhanced in the presence of human hAMECs, also found in the formed neovessels. These observations highlight the successful integration of a valuable matrix and prevascularization cues to target angiogenesis/neovascularization in skin full-thickness excisional wounds. PMID:25361388

Cerqueira, Mariana Teixeira; da Silva, Lucília Pereira; Santos, Tírcia Carlos; Pirraco, Rogério Pedro; Correlo, Vítor Manuel; Reis, Rui Luís; Marques, Alexandra Pinto

2014-11-26

27

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

PubMed Central

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 phosphomannomutase (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 for glucose-1-phosphate (G1P); the catalytic efficiency was about 50-fold higher for G1P than it was for mannose-1-phosphate (M1P). The estimated apparent Km values for G1P and M1P were high, 0.33 and 1.27 mM, respectively. The pgmG gene allowed the recovery of alginate biosynthetic ability in a P. aeruginosa mutant with a defective algC gene. This result indicates that PgmG protein can convert mannose-6-phosphate into M1P in the initial steps of alginate biosynthesis and, together with other results, suggests that PgmG may convert glucose-6-phosphate into G1P in the gellan pathway. PMID:10788412

Videira, Paula A.; Cortes, Luísa L.; Fialho, Arsénio M.; Sá-Correia, Isabel

2000-01-01

28

Gum Arabic surface-modified magnetic nanoparticles for cancer therapy  

Microsoft Academic Search

The objective of this study is to investigate the influence of Gum Arabic-modified magnetic nanoparticles on cellular uptake. The ultimate goal is to develop a technique to promote the selective uptake of magnetic nanoparticles by cancer cells for cancer treatment. A novel use of magnetic fields and magnetic particles is to deliver therapeutic drugs at the desired time in the

U. Effiong; D. Williams; W. Otto; W. Anderson

2004-01-01

29

Preparation, characterization and in vitro digestibility of gellan and chitosan-gellan microgels.  

PubMed

Gellan microgels with potential application in delivery systems were obtained by physically cross-linked gellan gum. The microgels were produced by atomization followed by ionotropic gelation using CaCl2 (gellan/Ca) or KCl (gellan/K) as hardening agent and part of them were coated with chitosan in order to improve their resistance to gastric digestion. Size distribution, morphology and zeta potential of microgels were evaluated before and after in vitro digestion process. The long term stability was also evaluated. Spherical microparticles were obtained at gellan concentration above 0.6% w/w, showing average size among 70-120?m. Most of the coated and uncoated microgels showed stability in aqueous media, except the uncoated gellan/K microgel. The in vitro digestion evaluation showed that all particles maintained their size and shape after the gastric digestion step. However, the enteric digestion caused disintegration of microgels indicating their potential application for enteric delivery systems. The chitosan-coated microgels showed lower degree of fragmentation when compared to the uncoated microgels, indicating that the coating process enable a better control of microgels releasing properties during the enteric digestion. PMID:25498608

Vilela, Joice Aline Pires; Perrechil, Fabiana de Assis; Picone, Carolina Siqueira Franco; Sato, Ana Carla Kawazoe; Cunha, Rosiane Lopes da

2015-03-01

30

Gellan sulfate inhibits Plasmodium falciparum growth and invasion of red blood cells in vitro  

PubMed Central

Here, we assessed the sulfated derivative of the microbial polysaccharide gellan gum and derivatives of ? and ?-carrageenans for their ability to inhibit Plasmodium falciparum 3D7 and Dd2 growth and invasion of red blood cells in vitro. Growth inhibition was assessed by means of flow cytometry after a 96-h exposure to the inhibitors and invasion inhibition was assessed by counting ring parasites after a 20-h exposure to them. Gellan sulfate strongly inhibited invasion and modestly inhibited growth for both P. falciparum 3D7 and Dd2; both inhibitory effects exceeded those achieved with native gellan gum. The hydrolyzed ?-carrageenan and oversulfated ?-carrageenan were less inhibitory than their native forms. In vitro cytotoxicity and anticoagulation assays performed to determine the suitability of the modified polysaccharides for in vivo studies showed that our synthesized gellan sulfate had low cytotoxicity and anticoagulant activity. PMID:24740150

Recuenco, Frances Cagayat; Kobayashi, Kyousuke; Ishiwa, Akiko; Enomoto-Rogers, Yukiko; Fundador, Noreen Grace V.; Sugi, Tatsuki; Takemae, Hitoshi; Iwanaga, Tatsuya; Murakoshi, Fumi; Gong, Haiyan; Inomata, Atsuko; Horimoto, Taisuke; Iwata, Tadahisa; Kato, Kentaro

2014-01-01

31

21 CFR 172.665 - Gellan gum.  

Code of Federal Regulations, 2010 CFR

...P. elodea . (d) The additive meets the following specifications...locations.html. (e) The additive is used or intended for use in accordance with current good manufacturing practice as a stabilizer and...28) of this chapter. The additive may be used in foods...

2010-04-01

32

21 CFR 172.665 - Gellan gum.  

Code of Federal Regulations, 2011 CFR

...P. elodea . (d) The additive meets the following specifications...locations.html. (e) The additive is used or intended for use in accordance with current good manufacturing practice as a stabilizer and...28) of this chapter. The additive may be used in foods...

2011-04-01

33

21 CFR 172.665 - Gellan gum.  

Code of Federal Regulations, 2013 CFR

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

2013-04-01

34

Freeze–thaw stabilization of sweet potato starch gel by polysaccharide gums  

Microsoft Academic Search

Nine polysaccharide gums (sodium alginate, carboxymethyl cellulose, curdlan, gellan, guar gum, gum arabic, ?-carrageenan, locust bean, and xanthan) were compared for their stabilizing effects in sweet potato starch gel against repeated freeze–thawing (FT) treatments. The gums were added in starch gel at 0.3 or 0.6% (w\\/w, based on total gel weight), and total solid content in the gel was adjusted

M. H. Lee; M. H. Baek; D. S. Cha; H. J. Park; S. T. Lim

2002-01-01

35

Microwave assisted synthesis and characterization of acrylamide grafted gellan, application in drug delivery.  

PubMed

The synthesis of acrylamide-grafted-gellan gum was carried out by microwave-assisted free radical polymerization using cerric ammonium nitrate (CAN) as redox initiator. A series of graft copolymers, varying in amount of acrylamide, CAN and microwave irradiation time was prepared. The modified gum was extracted with 20% (v/v) methanol to remove the homopolymer formed during polymerization reaction. These graft copolymers were characterized by FTIR, (13)C NMR, CHN, SEM, rheological studies and DSC studies. Comparison of grafting parameters such as grafting efficiency, percentage grafting and percentage conversion were carried out among various series of graft copolymers and then correlating it with elemental analysis, DSC, viscosity results. The acute oral toxicity study of grated gum was evaluated as per OECD guideline. Tablets were prepared by incorporating antidiabetic drug metformin hydrochloride (MTF) in grafted gum along with excipients. In vitro studies were performed on prepared tablet formulations showing release up to 8 h. PMID:24751070

Vijan, Veena; Kaity, Santanu; Biswas, Soumen; Isaac, Jinu; Ghosh, Animesh

2012-09-01

36

Gum arabic-coated magnetic nanoparticles for potential application in simultaneous magnetic targeting and tumor imaging.  

PubMed

Magnetic iron oxide nanoparticles (MNP) coated with gum arabic (GA), a biocompatible phytochemical glycoprotein widely used in the food industry, were successfully synthesized and characterized. GA-coated MNP (GA-MNP) displayed a narrow hydrodynamic particle size distribution averaging about 100 nm; a GA content of 15.6% by dry weight; a saturation magnetization of 93.1 emu/g Fe; and a superparamagnetic behavior essential for most magnetic-mediated applications. The GA coating offers two major benefits: it both enhances colloidal stability and provides reactive functional groups suitable for coupling of bioactive compounds. In vitro results showed that GA-MNP possessed a superior stability upon storage in aqueous media when compared to commercial MNP products currently used in magnetic resonance imaging (MRI). In addition, significant cellular uptake of GA-MNP was evaluated in 9L glioma cells by electron spin resonance (ESR) spectroscopy, fluorescence microscopy, and MRI analyses. Based on these findings, it was hypothesized that GA-MNP might be utilized as a MRI-visible drug carrier in achieving both magnetic tumor targeting and intracellular drug delivery. Indeed, preliminary in vivo investigations validate this clinical potential. MRI visually confirmed the accumulation of GA-MNP at the tumor site following intravenous administration to rats harboring 9L glioma tumors under the application of an external magnetic field. ESR spectroscopy quantitatively revealed a 12-fold increase in GA-MNP accumulation in excised tumors when compared to contralateral normal brain. Overall, the results presented show promise that GA-MNP could potentially be employed to achieve simultaneous tumor imaging and targeted intra-tumoral drug delivery. PMID:19842043

Zhang, Lei; Yu, Faquan; Cole, Adam J; Chertok, Beata; David, Allan E; Wang, Jingkang; Yang, Victor C

2009-12-01

37

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

38

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

39

Gum biopsy  

MedlinePLUS

Biopsy - gingiva (gums) ... the mouth in the area of the abnormal gum tissue. You may also have an injection of numbing medicine. A small piece of gum tissue is removed and checked for problems in ...

40

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

PubMed Central

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

2012-01-01

41

Process optimization for fabrication of gellan based electrospun nanofibers.  

PubMed

In this investigation, the nanofiber formation ability of gellan, a FDA approved low cost natural polysaccharide, has been achieved for the first time using electrospinning technique. The gellan based ultrafine nanofibers were fabricated by using a blend mixture of gellan with another biodegradable polymer polyvinyl alcohol (PVA). The morphology of resulting gellan-PVA nanofibers was analyzed using field emission scanning electron microscopy (FESEM). The mass ratio of 50:50 for gellan:PVA was recorded as an optimum solution ratio to obtain uniform bead free nanofibers with an average diameter of 40 ± 15.8 nm. Data depicted that among different parameters evaluated, viscosity and the mass ratio of gellan:PVA were the key parameters that influence the nanofiber morphology and diameter. PMID:24815395

Vashisth, Priya; Pruthi, Parul A; Singh, Rajesh P; Pruthi, Vikas

2014-08-30

42

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

43

Gum Disease  

MedlinePLUS

... plaque can be tougher. Plus, some medical conditions (including diabetes and Down syndrome) and certain medicines increase ... more vulnerable to infection anywhere in the body, including your gums. Girls have a higher risk of ...

44

Nicotine Gum  

MedlinePLUS

... techniques. Nicotine gum is in a class of medications called smoking cessation aids. It works by providing nicotine to your body to decrease the withdrawal symptoms experienced when smoking is stopped ...

45

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

46

Exopolysaccharide of the gellan family: prospects and potential  

Microsoft Academic Search

The use of microbial polysaccharides in the food, pharmaceutical and chemical industries has increased steadily during the past decade. The biopolymer gellan is a more recent addition to the family of microbial polysaccharides that is gaining much importance due to its novel property of forming thermo-reversible gels when heated and cooled. It is produced and marketed by some companies of

R. M. Banik; B. Kanari; S. N. Upadhyay

2000-01-01

47

Tamarind seed polysaccharide-gellan mucoadhesive beads for controlled release of metformin HCl.  

PubMed

The paper describes the development, optimization and evaluation of tamarind seed polysaccharide (TSP)-blended gellan gum (GG) mucoadhesive beads containing metformin HCl through Ca(2+)-ion cross-linked ionic gelation for oral drug delivery. Effects of GG to TSP ratio and cross-linker (CaCl2) concentration on the drug encapsulation efficiency (DEE, %), and cumulative drug release after 10h (R10h, %) of TSP-GG mucoadhesive beads containing metformin HCl were optimized by 32 factorial design. The optimized mucoadhesive beads (F-O) showed DEE of 95.73 ± 4.02%, R10h of 61.22 ± 3.44% and mean diameter of 1.70 ± 0.24 mm.These beads were characterized by SEM and FTIR analyses. The in vitro drug release from these beads showed controlled-release (zero-order) pattern over a period of 10h.The optimized TSP-GG 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:24528714

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

2014-03-15

48

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

49

Physicochemical properties and biological activities of DEAE-derivatized Sphingomonas gellan.  

PubMed

Physicochemical characteristics and biological activities of Sphingomonas gellan (S-gellan) were investigated. The S-gellan weight fractions of Glc and GlcUA were 0.45 and 0.25, respectively, and the molar ratio of Glc:Rha:GlcUA was approximately 4:2:3. The S-gellan was chemically derivatized with diethylaminoethyl chloride-HCl (DEAE-HCl), and the resulting modified S-gellan contained both positive and negative charges. The elemental and IR analyses were conducted to confirm the successful incorporation of DEAE groups into S-gellan. A large increase in nitrogen fraction was observed from the derivatized S-gellan by elemental analysis. The IR absorption bands induced by C-H, C-N, and C-O-C stretching were noticeable at 2950, 1310-1380, and 1000-1150 cm(-1), respectively, resulting from the DEAE substitution. The characteristic CH3 and CH2 peaks originated from the DEAE group were detected in the 1H NMR spectrum of the derivatized S-gellan as well. The solubility of native S-gellan was improved almost twice from 40% to 75% after DEAE derivatization, while water holding capacity (WHC) drastically decreased from 10026% to 245%. Oil binding capacity (OBC) of S-gellan also significantly dropped from 1528% to 331% after the derivatization. The bile acid binding capacity of S-gellan was indirectly determined by measuring the holding capability of cholic acid inside the dialysis membrane (MWCO 12,000-14,000 Da). Once S-gellan was DEAE derivatized, there was substantial increase in the cholic acid retardation index (CRI). Up to 9 h of dialysis, the derivatized S-gellan released 29.3% less of cholic acid compared to the control group that did not contain S-gellan. From these results of the improved water solubility and stronger bile acid binding capacity, it would be suggested that the DEAE-derivatized S-gellan has more advantages than gellan itself for functional food applications. PMID:16076099

Yoo, Sang-Ho; Lee, Kyung Hee; Lee, Ji-Soo; Cha, Jaeho; Park, Cheon Seok; Lee, Hyeon Gyu

2005-08-10

50

Physicochemical characteristics of a thermostable gellan lyase from Geobacillus stearothermophilus 98.  

PubMed

A purified thermostable gellan lyase, produced by a thermophilic bacterium, Geobacillus stearothermophilus 98, was characterized in relation to its physicochemical properties. The gellan lyase was established to have a molecular weight of 216 kDa, defined by capillary gel electrophoresis. Amino acid analysis revealed high quantities of Lys, His, Ala, Val, Ile, Glx, and Pro residues. The circular dichroism revealed 45% beta-structure and practically lack of a-spiral domains. Kinetic studies showed high affinity of the enzyme to gellan as a substrate (Km = 0.21 microM). The thermal denaturation investigated by cicular dichroism showed a highly cooperative transition with a midpoint (Tm) at about 75 degrees C. A single product was identified after enzyme action on gellan. Large exothermic aggregation near Tm was observed by differential scanning calorimetry. Two types of gellan lyase crystals were reproducibly isolated. PMID:20469643

Derekova, Anna; Atanassova, Miroslava; Christova, Petya; Tchorbanov, Bojidar; Shosheva, Alexandra; Mandeva, Rossitsa; Rodríguez-Alonso, Patricia; Garabal, Jose I; Kambourova, Margarita

2010-01-01

51

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

52

Brain Functional Network for Chewing of Gum  

Microsoft Academic Search

\\u000a Recent studies showed that gum-chewing induced significant increases in cerebral blood flow and blood-oxygenation level in\\u000a the widespread brain regions. However, little is known about the underlying mechanism of chewing-induced regional interconnection\\u000a and interaction within the brain. In this study, we investigated the human brain functional network during chewing of gum\\u000a by using functional magnetic resonance imaging and complex network

Ming Ke; Hui Shen; Zongtan Zhou; Xiaolin Zhou; Dewen Hu; Xuhui Chen

53

Immune reactivities against gums.  

PubMed

Context • Different kinds of gums from various sources enjoy an extremely broad range of commercial and industrial use, from food and pharmaceuticals to printing and adhesives. Although generally recognized as safe by the US Food and Drug Administration (FDA), gums have a history of association with sensitive or allergic reactions. In addition, studies have shown that gums have a structural, molecular similarity to a number of common foods. A possibility exists for cross-reactivity. Objective • Due to the widespread use of gums in almost every aspect of modern life, the overall goal of the current investigation was to determine the degree of immune reactivity to various gum antigens in the sera of individuals representing the general population. Design • The study was a randomized, controlled trial. Participants • 288 sera purchased from a commercial source.Outcome Measures • The sera was screened for immunoglobulin G (IgG) and immunoglobulin E (IgE) antibodies against extracts of mastic gum, carrageenan, xantham gum, guar gum, gum tragacanth, locust bean gum, and ?-glucan, using indirect enzyme-linked immunosorbent assay (ELISA) testing. For each gum antigen, inhibition testing was performed on the 4 sera that showed the highest IgG and IgE immune reactivity against the different gums used in the study. Inhibition testing on these same sera for sesame albumin, lentil, corn, rice, pineapple, peanut, pea protein, shrimp, or kidney bean was used to determine the cross-reactivity of these foods with the gum.Results • Of the 288 samples, 4.2%-27% of the specimens showed a significant elevation in IgG antibodies against various gums. Only 4 of 288, or 1.4%, showed a simultaneous elevation of the IgG antibody against all 7 gum extracts. For the IgE antibody, 15.6%-29.1% of the specimens showed an elevation against the various gums. A significant percentage of the specimens, 12.8%, simultaneously produced IgE antibodies against all 7 tested extracts. Conclusions • Overall, the percentage of elevation in IgE antibodies against different gum extracts, with the exception of carrageenan, was much higher than for the IgG antibody. The results of the current study showed that a subgroup of healthy individuals who produced not only IgG but also IgE antibodies against various gums may suffer from hidden food immune reactivities and sensitivities. Further study is needed to examine the clinical importance of gums and cross-reactive food antibodies in symptomatic individuals. PMID:25599187

Vojdani, Aristo; Vojdani, Charlene

2015-01-01

54

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

55

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

56

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

57

Gum Disease and Men  

MedlinePLUS

... than men with healthy gums. Specifically, men with periodontal disease may be 49 percent more likely than women to develop kidney cancer, 54 percent ... Tuesday, September 23, 2014 American Academy of Periodontology ...

58

Gum Disease in Children  

MedlinePLUS

... types of gum disease in children. Types of periodontal diseases in children Chronic gingivitis is common in ... cause the teeth to become loose. Signs of periodontal disease Four basic signs will alert you to ...

59

21 CFR 582.7349 - Sterculia gum.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Sterculia gum. 582.7349 Section 582.7349 Food and Drugs...AS SAFE Stabilizers § 582.7349 Sterculia gum. (a) Product. Sterculia gum (karaya gum). (b) Conditions of use....

2011-04-01

60

21 CFR 582.7349 - Sterculia gum.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Sterculia gum. 582.7349 Section 582.7349 Food and Drugs...AS SAFE Stabilizers § 582.7349 Sterculia gum. (a) Product. Sterculia gum (karaya gum). (b) Conditions of use....

2014-04-01

61

21 CFR 582.7349 - Sterculia gum.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Sterculia gum. 582.7349 Section 582.7349 Food and Drugs...AS SAFE Stabilizers § 582.7349 Sterculia gum. (a) Product. Sterculia gum (karaya gum). (b) Conditions of use....

2012-04-01

62

21 CFR 582.7349 - Sterculia gum.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Sterculia gum. 582.7349 Section 582.7349 Food and Drugs...AS SAFE Stabilizers § 582.7349 Sterculia gum. (a) Product. Sterculia gum (karaya gum). (b) Conditions of use....

2013-04-01

63

21 CFR 582.7349 - Sterculia gum.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Sterculia gum. 582.7349 Section 582.7349 Food and Drugs...AS SAFE Stabilizers § 582.7349 Sterculia gum. (a) Product. Sterculia gum (karaya gum). (b) Conditions of use....

2010-04-01

64

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

65

Cetyl gellan copolymer micelles and hydrogels: in vitro and pharmacodynamic assessment for drug delivery.  

PubMed

In this study, gellan polymer was conferred amphiphilic character by conjugating alkyl carbon chain (C16) to its backbone via etherification reaction. The amphiphilic copolymer self-assembled into water and formed spherical micellar structures with a mean diameter of 832 nm. Copolymer micellization caused a considerable rise in solubility of simvastatin in water. Later on, the micelle-incorporated drug and pure drug were loaded into aluminium gellan hydrogel beads and characterized. Scanning electron microscopy revealed spherical shape of the beads. The drug entrapment efficiency of the beads (917-927 ?m) was found to be 90-94%. Higher dissolution efficiency and consequently, higher rate of drug dissolution was evident in phosphate buffer solution (pH 6.8) than in HCl solution (pH 1.2). The changes in drug release rate as a function of pH correlated with the swelling behaviour of beads. The release of drug was controlled by anomalous diffusion mechanism. Fourier transform infrared spectroscopy and X-ray diffraction analyses suggested compatibility of drug in the beads. The gellan beads, loaded with micellar drug, reduced 83.45% LDL-cholesterol level in rabbit model following 18 h of oral administration. Thus, the gellan beads containing micellar drug showed their potential in controlling drug release rate and improving pharmacodynamic activity. PMID:25316420

Kundu, Payel; Maiti, Sabyasachi

2015-01-01

66

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

67

The effect of added sucrose and corn syrup on the physical properties of gellan—gelatin mixed gels  

Microsoft Academic Search

Gellan—gelatin blends in the presence of high levels of co-solute (sucrose plus corn syrup) are thermally stable systems with increased gel strength. Dynamic oscillatory analysis (frequency, time—temperature and strain sweeps) demonstrated that the two polymeric components form gelled phases with diverse viscoelastic properties. Gellan continuous mixtures could be prepared easily since the polysaccharide is capable of forming a supporting matrix

Maria Papageorgiou; Stefan Kasapis

1995-01-01

68

21 CFR 582.7351 - Gum tragacanth.  

Code of Federal Regulations, 2012 CFR

...6 2012-04-01 2012-04-01 false Gum tragacanth. 582.7351 Section 582.7351...RECOGNIZED AS SAFE Stabilizers § 582.7351 Gum tragacanth. (a) Product. Tragacanth (gum tragacanth). (b) Conditions of use....

2012-04-01

69

21 CFR 582.7351 - Gum tragacanth.  

Code of Federal Regulations, 2013 CFR

...6 2013-04-01 2013-04-01 false Gum tragacanth. 582.7351 Section 582.7351...RECOGNIZED AS SAFE Stabilizers § 582.7351 Gum tragacanth. (a) Product. Tragacanth (gum tragacanth). (b) Conditions of use....

2013-04-01

70

21 CFR 582.7351 - Gum tragacanth.  

Code of Federal Regulations, 2010 CFR

...6 2010-04-01 2010-04-01 false Gum tragacanth. 582.7351 Section 582.7351...RECOGNIZED AS SAFE Stabilizers § 582.7351 Gum tragacanth. (a) Product. Tragacanth (gum tragacanth). (b) Conditions of use....

2010-04-01

71

21 CFR 582.7351 - Gum tragacanth.  

Code of Federal Regulations, 2014 CFR

...6 2014-04-01 2014-04-01 false Gum tragacanth. 582.7351 Section 582.7351...RECOGNIZED AS SAFE Stabilizers § 582.7351 Gum tragacanth. (a) Product. Tragacanth (gum tragacanth). (b) Conditions of use....

2014-04-01

72

21 CFR 582.7351 - Gum tragacanth.  

Code of Federal Regulations, 2011 CFR

...6 2011-04-01 2011-04-01 false Gum tragacanth. 582.7351 Section 582.7351...RECOGNIZED AS SAFE Stabilizers § 582.7351 Gum tragacanth. (a) Product. Tragacanth (gum tragacanth). (b) Conditions of use....

2011-04-01

73

Mind Your Mouth: Preventing Gum Disease  

MedlinePLUS

... can lead to gum disease—technically known as periodontal disease. The most common and mild type of ... and professional cleaning. Don’t smoke. Web sites: Periodontal (Gum) Disease NIH Senior Health: Gum Disease Taking ...

74

Tips for Removing Gum without Cutting Hair  

MedlinePLUS

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

75

Phase transition of locust bean gum-, tara gum- and guar gum-water systems  

Microsoft Academic Search

Phase transition behaviour of neutral galactomannans, i.e., locust bean gum (LBG), tara gum (Tara-G) and guar gum (GG)-water\\u000a systems is investigated. In this study, water content {Wc=(gram of water)\\/(gram of dry sample)} of these systems was varied from 0.2 to 3.6 g g-1. In the DSC heating curves, glass transition (Tg), cold crystallization (Tcc) and melting (Tm) were observed in

S. Naoi; T. Hatakeyama; H. Hatakeyama

2002-01-01

76

Magnesium binding by gum arabic, locust bean gum, and arabinogalactan  

Microsoft Academic Search

The ability of gum arabic (GA), locust bean gum (LBG), and arabinogalactan (ABO) to complex with magnesium was investigated. Uronic acid presence, total endogenous magnesium, free endogenous magnesium over a pH range 6–8, ability to complex added magnesium, and ability to bind endogenous magnesium after partial digestion were determined. Only GA contained uronic acid, and also contained the most magnesium

M. E. Kunkel; A. Seo; T. A. Minten

1997-01-01

77

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

78

Enzymatically-treated guar gums  

SciTech Connect

A method is described of recovering oil from an oil bearing formation by fracturing the step of inserting into the formation, at high pressure, an aqueous composition comprising guar gum in water. The guar gum is first coated and impregnated, while in the solid particulate state, with an aqueous solution of a hydrolytic enzyme.

Carter, W.H.; Srivastava, V.K.

1987-07-28

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

Bacterial exopolysaccharide based magnetic nanoparticles: a versatile nanotool for cancer cell imaging, targeted drug delivery and synergistic effect of drug and hyperthermia mediated cancer therapy.  

PubMed

Microbial exopolysaccharides (EPSs) are highly heterogeneous polymers produced by fungi and bacteria that have garnered considerable attention and have remarkable potential in various fields, including biomedical research. The necessity of biocompatible materials to coat and stabilize nanoparticles is highly recommended for successful application of the same in biomedical regime. In our study we have coated magnetic nanoparticles (MNPs) with two bacterial EPS-mauran (MR) and gellan gum (GG). The biocompatibility of EPS coated MNPs was enhanced and we have made it multifunctional by attaching targeting moiety, folate and with encapsulation of a potent anticancerous drug, 5FU. We have conjugated an imaging moiety along with nanocomposite to study the effective uptake of nanoparticles. It was also observed that the dye labeled folate targeted nanoparticles could effectively enter into cancer cells and the fate of nanoparticles was tracked with Lysotracker. The biocompatibility of EPS coated MNPs and synergistic effect of magnetic hyperthermia and drug for enhanced antiproliferation of cancer cells was also evaluated. More than 80% of cancer cells was killed within a period of 60 min when magnetic hyperthermia (MHT) was applied along with drug loaded EPS coated MNPs, thus signifying the combined effect of drug loaded MNPs and MHT. Our results suggests that MR and GG coated MNPs exhibited excellent biocompatibility with low cell cytotoxicity, high therapeutic potential, and superparamagnetic behavior that can be employed as prospective candidates for bacterial EPS based targeted drug delivery, cancer cell imaging and for MHT for killing cancer cells within short period of time. PMID:24749386

Sivakumar, Balasubramanian; Aswathy, Ravindran Girija; Sreejith, Raveendran; Nagaoka, Yutaka; Iwai, Seiki; Suzuki, Masashi; Fukuda, Takahiro; Hasumura, Takashi; Yoshida, Yasuhiko; Maekawa, Toru; Sakthikumar, Dasappan Nair

2014-06-01

81

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

82

'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.

Nichols, Kyle

83

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

84

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

85

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

86

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

87

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

88

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

89

GUM: A Portable Parallel Implementation of Haskell  

Microsoft Academic Search

GUM is a portable, parallel implementation of the Haskell functional language. Despite sustained research interest in parallel functional programming, GUM is one of the first such systems to be made publicly available.GUM is message-based, and portability is facilitated by using the PVM communications harness that is available on many multi-processors. As a result, GUM is available for both shared-memory (Sun

Philip W. Trinder; Kevin Hammond; James S. Mattson Jr.; A. S. Partridge; Simon L. Peyton Jones

1996-01-01

90

21 CFR 582.7339 - Guar gum.  

Code of Federal Regulations, 2013 CFR

...6 2013-04-01 2013-04-01 false Guar gum. 582.7339 Section 582.7339 Food and Drugs...RECOGNIZED AS SAFE Stabilizers § 582.7339 Guar gum. (a) Product. Guar gum. (b) Conditions of use. This substance...

2013-04-01

91

21 CFR 184.1339 - Guar gum.  

Code of Federal Regulations, 2011 CFR

... 3 2011-04-01 2011-04-01 false Guar gum. 184.1339 Section 184.1339 Food and Drugs...Specific Substances Affirmed as GRAS § 184.1339 Guar gum. (a) Guar gum is the natural substance obtained from the...

2011-04-01

92

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 Drugs...Specific Substances Affirmed as GRAS § 184.1339 Guar gum. (a) Guar gum is the natural substance obtained from the...

2010-04-01

93

21 CFR 582.7339 - Guar gum.  

Code of Federal Regulations, 2010 CFR

...6 2010-04-01 2010-04-01 false Guar gum. 582.7339 Section 582.7339 Food and Drugs...RECOGNIZED AS SAFE Stabilizers § 582.7339 Guar gum. (a) Product. Guar gum. (b) Conditions of use. This substance...

2010-04-01

94

21 CFR 582.7339 - Guar gum.  

Code of Federal Regulations, 2011 CFR

...6 2011-04-01 2011-04-01 false Guar gum. 582.7339 Section 582.7339 Food and Drugs...RECOGNIZED AS SAFE Stabilizers § 582.7339 Guar gum. (a) Product. Guar gum. (b) Conditions of use. This substance...

2011-04-01

95

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2010 CFR

...Drugs 3 2010-04-01 2009-04-01 true Gum tragacanth. 184.1351 Section 184.1351 Food...Specific Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several...

2010-04-01

96

21 CFR 573.1010 - Xanthan gum.  

Code of Federal Regulations, 2011 CFR

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

2011-04-01

97

21 CFR 573.1010 - Xanthan gum.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Xanthan gum. 573.1010 Section 573.1010 Food and Drugs... Food Additive Listing § 573.1010 Xanthan gum. The food additive xanthan gum may be safely used in animal feed as follows:...

2013-04-01

98

21 CFR 573.1010 - Xanthan gum.  

Code of Federal Regulations, 2014 CFR

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

2014-04-01

99

Periodontal (Gum) Disease Causes, Symptoms, and Treatments  

E-print Network

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

Bandettini, Peter A.

100

21 CFR 573.1010 - Xanthan gum.  

Code of Federal Regulations, 2012 CFR

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

2012-04-01

101

21 CFR 582.7339 - Guar gum.  

Code of Federal Regulations, 2012 CFR

...6 2012-04-01 2012-04-01 false Guar gum. 582.7339 Section 582.7339 Food and Drugs...RECOGNIZED AS SAFE Stabilizers § 582.7339 Guar gum. (a) Product. Guar gum. (b) Conditions of use. This substance...

2012-04-01

102

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2011 CFR

...Drugs 3 2011-04-01 2011-04-01 false Gum tragacanth. 184.1351 Section 184.1351 Food...Specific Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several...

2011-04-01

103

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2014 CFR

...Drugs 3 2014-04-01 2014-04-01 false Gum tragacanth. 184.1351 Section 184.1351 Food...Specific Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several...

2014-04-01

104

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2013 CFR

...Drugs 3 2013-04-01 2013-04-01 false Gum tragacanth. 184.1351 Section 184.1351 Food...Specific Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several...

2013-04-01

105

21 CFR 184.1339 - Guar gum.  

Code of Federal Regulations, 2014 CFR

... 3 2014-04-01 2014-04-01 false Guar gum. 184.1339 Section 184.1339 Food and Drugs...Specific Substances Affirmed as GRAS § 184.1339 Guar gum. (a) Guar gum is the natural substance obtained from the...

2014-04-01

106

21 CFR 582.7339 - Guar gum.  

Code of Federal Regulations, 2014 CFR

...6 2014-04-01 2014-04-01 false Guar gum. 582.7339 Section 582.7339 Food and Drugs...RECOGNIZED AS SAFE Stabilizers § 582.7339 Guar gum. (a) Product. Guar gum. (b) Conditions of use. This substance...

2014-04-01

107

21 CFR 184.1339 - Guar gum.  

Code of Federal Regulations, 2013 CFR

... 3 2013-04-01 2013-04-01 false Guar gum. 184.1339 Section 184.1339 Food and Drugs...Specific Substances Affirmed as GRAS § 184.1339 Guar gum. (a) Guar gum is the natural substance obtained from the...

2013-04-01

108

21 CFR 184.1351 - Gum tragacanth.  

Code of Federal Regulations, 2012 CFR

...Drugs 3 2012-04-01 2012-04-01 false Gum tragacanth. 184.1351 Section 184.1351 Food...Specific Substances Affirmed as GRAS § 184.1351 Gum tragacanth. (a) Gum tragacanth is the exudate from one of several...

2012-04-01

109

21 CFR 184.1339 - Guar gum.  

Code of Federal Regulations, 2012 CFR

... 3 2012-04-01 2012-04-01 false Guar gum. 184.1339 Section 184.1339 Food and Drugs...Specific Substances Affirmed as GRAS § 184.1339 Guar gum. (a) Guar gum is the natural substance obtained from the...

2012-04-01

110

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

111

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.

Hebrank, Mary R.

2013-01-01

112

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.

Center, Beacon L.

2009-10-13

113

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

114

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

115

7 CFR 160.7 - Gum spirits of turpentine.  

Code of Federal Regulations, 2011 CFR

...3 2011-01-01 2011-01-01 false Gum spirits of turpentine. 160.7 Section 160...STANDARDS FOR NAVAL STORES General § 160.7 Gum spirits of turpentine. The designation “gum spirits of turpentine” shall refer to...

2011-01-01

116

7 CFR 160.7 - Gum spirits of turpentine.  

Code of Federal Regulations, 2010 CFR

...3 2010-01-01 2010-01-01 false Gum spirits of turpentine. 160.7 Section 160...STANDARDS FOR NAVAL STORES General § 160.7 Gum spirits of turpentine. The designation “gum spirits of turpentine” shall refer to...

2010-01-01

117

7 CFR 160.7 - Gum spirits of turpentine.  

Code of Federal Regulations, 2013 CFR

...3 2013-01-01 2013-01-01 false Gum spirits of turpentine. 160.7 Section 160...STANDARDS FOR NAVAL STORES General § 160.7 Gum spirits of turpentine. The designation “gum spirits of turpentine” shall refer to...

2013-01-01

118

7 CFR 160.7 - Gum spirits of turpentine.  

Code of Federal Regulations, 2014 CFR

...3 2014-01-01 2014-01-01 false Gum spirits of turpentine. 160.7 Section 160...STANDARDS FOR NAVAL STORES General § 160.7 Gum spirits of turpentine. The designation “gum spirits of turpentine” shall refer to...

2014-01-01

119

7 CFR 160.7 - Gum spirits of turpentine.  

Code of Federal Regulations, 2012 CFR

...3 2012-01-01 2012-01-01 false Gum spirits of turpentine. 160.7 Section 160...STANDARDS FOR NAVAL STORES General § 160.7 Gum spirits of turpentine. The designation “gum spirits of turpentine” shall refer to...

2012-01-01

120

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.

121

Chronic effects of agar, guar gum, gum arabic, locust-bean gum, or tara gum in F344 rats and B6C3F1 mice.  

PubMed

Diets containing 25,000 (2.5%) or 50,000 ppm (5.0%) agar, guar gum, gum arabic, locust-bean gum or tara gum were fed to groups of 50 male and 50 female F344 rats and B6C3F1 mice for 103 wk. Separate groups of 50 rats and 50 mice of each sex served as controls for each study. There were no significant differences in survival between any of the dosed groups of rats or mice and their respective control groups. Depressions in body-weight gain greater than 10% for dosed groups relative to their respective control groups were observed for male (low dose only) and female mice fed diets containing agar, female mice fed diets containing guar gum (high dose only), male mice fed diets containing locust-bean gum (high dose only) and male and female mice fed diets containing tara gum (high dose only). Depressions in body-weight gain greater than 5% were observed for female rats fed diets containing agar, guar gum or gum arabic. There were no histopathological effects associated with the administration of the test materials. Under the conditions of these bioassays, none of the five polysaccharides was carcinogenic for F344 rats or B6C3F1 mice of either sex. PMID:6683227

Melnick, R L; Huff, J; Haseman, J K; Dieter, M P; Grieshaber, C K; Wyand, D S; Russfield, A B; Murthy, A S; Fleischman, R W; Lilja, H S

1983-06-01

122

FT-Raman spectroscopy of gums of technological significance  

NASA Astrophysics Data System (ADS)

The FT-Raman spectra of four technically important gums, namely, locust bean gum, karaya gum (five varieties), gum tragacanth (nine varieties) and gum ghatti (four varieties), are reported. Bands characteristic of each gum which can be used for their identification are identified and assigned to molecular species where possible. Because the gums contain similar chemical components, an integral part of the current study has been self-deconvolution of the Raman spectra. The spectra provide the first examples of a database for gums using a nondestructive analytical technique.

Edwards, H. G. M.; Falk, M. J.; Sibley, M. G.; Alvarez-Benedi, J.; Rull, F.

1998-07-01

123

Study of emulsions stabilized with Phaseolus vulgaris or Phaseolus coccineus with the addition of Arabic gum, locust bean gum and xanthan gum  

Microsoft Academic Search

The properties of o\\/w emulsions stabilized with 1%w\\/v common bean (Phaseolus vulgaris L.), V or scarlet runner bean (P. coccineus L.), Coc extracted by isoelectric precipitation or ultrafiltration, at pH 7.0 and 5.5, with the addition of Arabic gum, locust bean gum, xanthan gum and a mixture of xanthan gum–locust bean gum (0.1%w\\/v and 0.25%w\\/v) are studied. The stability of

Eleousa A. Makri; Georgios I. Doxastakis

2006-01-01

124

Guar gum, xanthan gum, and HPMC can define release mechanisms and sustain release of propranolol hydrochloride.  

PubMed

The objectives were to characterize propranolol hydrochloride-loaded matrix tablets using guar gum, xanthan gum, and hydroxypropylmethylcellulose (HPMC) as rate-retarding polymers. Tablets were prepared by wet granulation using these polymers alone and in combination, and physical properties of the granules and tablets were studied. Drug release was evaluated in simulated gastric and intestinal media. Rugged tablets with appropriate physical properties were obtained. Empirical and semi-empirical models were fit to release data to elucidate release mechanisms. Guar gum alone was unable to control drug release until a 1:3 drug/gum ratio, where the release pattern matched a Higuchi profile. Matrix tablets incorporating HPMC provided near zero-order release over 12 h and erosion was a contributing mechanism. Combinations of HPMC with guar or xanthan gum resulted in a Higuchi release profile, revealing the dominance of the high viscosity gel formed by HPMC. As the single rate-retarding polymer, xanthan gum retarded release over 24 h and the Higuchi model best fit the data. When mixed with guar gum, at 10% or 20% xanthan levels, xanthan gum was unable to control release. However, tablets containing 30% guar gum and 30% xanthan gum behaved as if xanthan gum was the sole rate-retarding gum and drug was released by Fickian diffusion. Release profiles from certain tablets match 12-h literature profiles and the 24-h profile of Inderal(®) LA. The results confirm that guar gum, xanthan gum, and HPMC can be used for the successful preparation of sustained release oral propranolol hydrochoride tablets. PMID:21174179

Mughal, Muhammad Akhlaq; Iqbal, Zafar; Neau, Steven Henry

2011-03-01

125

Problem Solving: Bubble Gum Contest  

NSDL National Science Digital Library

This professional development video clip presents students engaged in The Common Core Practice Standard #1âMake 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.

Boston, Wghb

2013-01-01

126

Nitrogen conversion factors for the proteinaceous content of gums permitted as food additives  

Microsoft Academic Search

Nitrogen conversion factors for gum arabic (Acacia Senegal (L.) Willd.), gum tragacanth (Asiatic Astragalus spp.), gum karaya (Sterculia spp.), guar gum (Cyamopsis spp.), locust bean (carob) gum (Ceratonia spp.), tara gum (Caesalpinia spp.), and xanthan gum (Xanthomonas campestris) have been calculated from data for the amino acid compositions of their proteinaceous components. The factors derived differ from the arbitrary values

D. M. W. Anderson

1986-01-01

127

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

PubMed

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

Johnson, Andrew J; Miles, Christopher

2008-05-01

128

Interstellar gas in the Gum Nebula  

NASA Technical Reports Server (NTRS)

A survey of the interstellar gas near the Gum Nebula by optical observation of 67 stars at Ca II, 42 stars at Na I, and 14 stars in the UV with the Copernicus satellite provided radial velocities and column densities for all resolved absorption components. Velocity dispersions for gas in the Gum Nebula are not significantly larger than in the general interstellar medium; the ionization structure is predominantly that of an H II region with moderately high ionization. Denser, more highly ionized clouds are concentrated toward the Gum Nebula; these clouds do not show the anomalously high ionization observed in the Vela remnant clouds.

Wallerstein, G.; Jenkins, E. B.; Silk, J.

1980-01-01

129

Viscoelastic properties of xanthan galactomannan mixtures: comparison of guar gum with locust bean gum  

Microsoft Academic Search

The rheological behaviour of xanthanguar gum systems has been investigated and compared to that of xanthanlocust bean gum mixtures using oscillatory shear and creep-recovery measurements. The total polysaccharide concentration was kept constant at 0.5% w\\/w, the xanthangalactomannan ratio ranged from 199 to 9010 and three ionic strengths were studied. As for xanthanlocust bean gum mixtures, strong synergistic phenomena were exhibited

Catherine Schorsch; Catherine Garnier; Jean-Louis Doublier

1997-01-01

130

Comparing Fractions: Bubble Gum Blowing Contest  

NSDL National Science Digital Library

In this interactive activity adapted from Anneberg Learner’s Teaching Math Grades 3–5, compare fractions on number lines to determine which class of students wins bubble-gum-blowing contests.

Foundation, Wgbh E.

2012-06-29

131

Soft-Tissue Grafts (for Receding Gums)  

MedlinePLUS

... types of soft-tissue grafts: Free gingival grafts Connective-tissue grafts Pedicle grafts In a free gingival graft, ... need to have the gums enlarged. In a connective-tissue graft, a flap is cut in the roof ...

132

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

133

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

134

Production of Recombinant Plant Gum With Tobacco Cell Culture in Bioreactor  

E-print Network

Production of Recombinant Plant Gum With Tobacco Cell Culture in Bioreactor and Gum.interscience.wiley.com). DOI: 10.1002/bit.20441 Abstract: Many plant gums, such as gum arabic, contain hydroxyproline-based gum, designated gum arabic-8 or (GA)8. (GA)8 encoded eight repeats of the consensus polypeptide

Kieliszewski, Marcia

135

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

136

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

137

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

138

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

139

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

140

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

141

Interstellar gas in the Gum Nebula  

SciTech Connect

We have surveyed the interstellar gas in and around the Gum Nebula by optically observing 67 stars at Ca II, 42 stars at Na I, and 14 stars in the ultraviolet with the Copernicus satellite. Velocity dispersions for gas in the Gum Nebula, excluding the region of Vela remnant filaments, are not significantly larger than in the general interstellar medium. The ionization structure is predominantly that of an H II region with moderately high ionization, i.e., strong Si III and S III, in clouds with Vertical BarV/sub LSR/Vertical Bar> or approx. =10 km s/sup -1/. Furthermore, we find an increase in fine-structure excitation with increasing component LSR velocity, suggestive of ram-pressure confinement for the intermediate-velocity clouds. These denser, more highly ionized clouds appear to be concentrated toward the inner Gum Nebula, where a somewhat higher velocity dispersion is found than in the outer regions. Clouds in the Gum Nebula do not show the anomalously high ionization seen in the Vela remnant clouds. The observational data are generally consistent with a model of the Gum Nebula as an H II region ionized by OB stars and stirred up by multiple stellar winds.

Wallerstein, G.; Silk, J.; Jenkins, E.B.

1980-09-15

142

75 FR 44251 - Wood Oils and Gums, and Streptomyces  

Federal Register 2010, 2011, 2012, 2013, 2014

...EPA-HQ-OPP-2010-0441; FRL-8829-8 Wood Oils and Gums, and Streptomyces Strain...tank mixes with chemical fungicides. The Wood Oils and Gums Registration Review Case no longer contains any other wood oils or gums with active ingredients...

2010-07-28

143

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

144

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

145

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

146

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

147

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

148

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...

149

Influence of xanthan gum and locust bean gum upon flow and thixotropic behaviour of food emulsions containing modified starch  

Microsoft Academic Search

Low oil content mayonnaises are food emulsions which exhibit shear thinning and thixotropic behaviour. They include generally modified starch in their formulation. In this work we study the effect of substituting part of this starch with other natural gums, such as xanthan gum or locust bean gum, upon the consistency and stability of the emulsions in relation to stirring. The

M. Dolz; M. J. Hernández; J. Delegido; M. C. Alfaro; J. Muñoz

2007-01-01

150

Nitrogen conversion factors for the proteinaceous content of gums permitted as food additives.  

PubMed

Nitrogen conversion factors for gum arabic (Acacia senegal (L.) Willd.), gum tragacanth (Asiatic Astragalus spp.), gum karaya (Sterculia spp.), guar gum (Cyamopsis spp.), locust bean (carob) gum (Ceratonia spp.), tara gum (Caesalpinia spp.), and xanthan gum (Xanthomonas campestris) have been calculated from data for the amino acid compositions of their proteinaceous components. The factors derived differ from the arbitrary values (5.7 or 6.25) at present specified by international regulatory authorities for some emulsifiers, stabilizers and thickeners. PMID:3743832

Anderson, D M

1986-01-01

151

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

152

How and why do South Asians attend GUM clinics? Evidence from contrasting GUM clinics across England  

Microsoft Academic Search

BackgroundImproving access to sexual healthcare is a priority in the UK, especially for ethnic minorities. Though South Asians in the UK report low levels of sexual ill health, few data exist regarding their use of genitourinary medicine (GUM) services.ObjectivesTo describe reasons for attendance at GUM clinics among individuals of South Asian origin relative to patients of other ethnicities.Methods4600 new attendees

Jyoti Dhar; Catherine A Griffiths; Jackie A Cassell; Lorna Sutcliffe; Gary M Brook; Catherine H Mercer

2010-01-01

153

Pressure cell assisted solution characterization of polysaccharides. 2. Locust bean gum and tara gum.  

PubMed

Following the work carried out on guar gum in our first paper of a series, the "pressure cell" solubilization method was applied to two other less highly substituted galactomannans: locust bean gum (LBG) and tara gum. True molecular solution of the polymers was achieved using appropriate temperature, time, and pressure regimes. The technique of capillary viscometry was used to determine the intrinsic viscosity [eta] of the "pressure cell" treated and untreated samples. Molecular weight (M(w)) and radius of gyration (R(g)) were determined by light scattering. The data obtained for LBG and tara gum were compared statistically with reliable data found for guar gum in the literature. The variation in [eta] with M(w) followed the Mark-Houwink-Sakurada relationship, giving the exponent alpha = 0.74 +/- 0.01 for galactomannans consistent with random coil behavior. The characteristic ratio, C(infinity), and the chain persistence length, L(p), were both calculated for LBG and tara gum using the Burchard-Stockmayer-Fixman (BSF) method which is appropriate for flexible to semiflexible chains. A general value of 9 < C(infinity) < 16 and 3 < L(p) < 5 nm can now be estimated with statistical confidence for all galactomannans. According to our statistical analysis, the chain persistence length was found to be insensitive to the degree of galactose substitution. PMID:12099820

Picout, David R; Ross-Murphy, Simon B; Jumel, Kornelia; Harding, Stephen E

2002-01-01

154

Xanthan gum: production, recovery, and properties  

Microsoft Academic Search

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

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

2000-01-01

155

Teaching Measurement and Uncertainty the GUM Way  

NASA Astrophysics Data System (ADS)

This paper describes a course aimed at developing understanding of measurement and uncertainty in the introductory physics laboratory. The course materials, in the form of a student workbook, are based on the probabilistic framework for measurement as recommended by the International Organization for Standardization in their publication Guide to the Expression of Uncertainty in Measurement (GUM).

Buffler, Andy; Allie, Saalih; Lubben, Fred

2008-12-01

156

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 gum on cortisol, testosterone, and progesterone concentrations measured in saliva samples collected

Schultheiss, Oliver C.

157

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.The Journal of Antibiotics advance online publication, 20 August 2014; doi:10.1038/ja.2014.114. PMID:25138141

Kora, Aruna Jyothi; Sashidhar, Rao Beedu

2014-08-20

158

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. 454...EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GUM AND WOOD CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Gum Rosin and Turpentine Subcategory §...

2014-07-01

159

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. 454...EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GUM AND WOOD CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Gum Rosin and Turpentine Subcategory §...

2012-07-01

160

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

Federal Register 2010, 2011, 2012, 2013, 2014

...A-433-811, A-570-985] Xanthan Gum From Austria and the People's Republic...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

161

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. 454...CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GUM AND WOOD CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Gum Rosin and Turpentine Subcategory §...

2011-07-01

162

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. 454...EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GUM AND WOOD CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Gum Rosin and Turpentine Subcategory §...

2013-07-01

163

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. 454...CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GUM AND WOOD CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Gum Rosin and Turpentine Subcategory §...

2010-07-01

164

Linear Mixed Models: Gum and Beyond  

NASA Astrophysics Data System (ADS)

In Annex H.5, the Guide to the Evaluation of Uncertainty in Measurement (GUM) [1] recognizes the necessity to analyze certain types of experiments by applying random effects ANOVA models. These belong to the more general family of linear mixed models that we focus on in the current paper. Extending the short introduction provided by the GUM, our aim is to show that the more general, linear mixed models cover a wider range of situations occurring in practice and can be beneficial when employed in data analysis of long-term repeated experiments. Namely, we point out their potential as an aid in establishing an uncertainty budget and as means for gaining more insight into the measurement process. We also comment on computational issues and to make the explanations less abstract, we illustrate all the concepts with the help of a measurement campaign conducted in order to challenge the uncertainty budget in calibration of accelerometers.

Arendacká, Barbora; Täubner, Angelika; Eichstädt, Sascha; Bruns, Thomas; Elster, Clemens

2014-04-01

165

Biodegradation of Xanthan Gum by Bacillus sp  

PubMed Central

Strains tentatively identified as Bacillus sp. were isolated from sewage sludge and soil and shown to elaborate extracellular enzymes that degrade the extracellular polysaccharide (xanthan gum, polysaccharide B-1459) of Xanthomonas campestris NRRL B-1459. Enzyme production by one strain was greatly enhanced when the strain was incubated in a mixed culture. Products of degradation were identified as d-glucuronic acid, d-mannose, pyruvylated mannose, 6-O-acetyl d-mannose, and a (1?4)-linked glucan. These products correlate with the known structure of the gum. The complexity of the product mixture indicated that the xanthanase was a mixture of carbohydrases. The xanthanase complexes were similar to one another in temperature stability, pH and temperature optima, degree of substrate degradation, and enzymolysis products. Differences in pH stability, salt tolerance, recoverability, and yields of enzyme were observed. PMID:16346068

Cadmus, Martin C.; Jackson, Linda K.; Burton, Kermit A.; Plattner, Ronald D.; Slodki, Morey E.

1982-01-01

166

Plasma nicotine levels after cigarette smoking and chewing nicotine gum  

Microsoft Academic Search

Plasma nicotine levels were measured over seven hours of smoking cigarettes (1-2 mg nicotine) in a single subject under standardised conditions, and were compared with the levels obtained from chewing-gum containing either 2 mg or 4 mg nicotine. Levels comparable to those resulting from smoking were not obtained with the 2-mg gum, but peak levels on the 4-mg gum averaged

M A Russell; C Feyerabend; P V Cole

1976-01-01

167

Bioavailability of two formulations of acetylsalicylic acid gums.  

PubMed

Bioavailability studies have been performed with ten healthy volunteers on different dosage forms of acetylsalicylic acid (ASA) in order to assess the bioavailability of two different ASA gums compared with commercial ASA tablets. The results of this study show that ASA is more readily absorbed and eliminated after administration of gum formulations than after administration of tablets, but the bioavailability obtained from the gums was lower than that observed from the tablets. PMID:1438512

Bousquet, E; Tirendi, S; Bonina, F P; Montenegro, L; Bianchi, A; Ciampini, N

1992-08-01

168

Extraction, purification and physicochemical characterization of fenugreek gum  

Microsoft Academic Search

Fenugreek gum was extracted from defatted, deactivated fenugreek seeds (produced in Canada) at 10°C for 2h to give a yield of 22% with only 2.36% protein contaminates. Further purification of fenugreek gum was achieved by treating the gum solution with pronase to reduce the protein contaminates to 0.57%. High performance size exclusion chromatography showed that the enzyme treatment did not

Y Brummer; W Cui; Q Wang

2003-01-01

169

Flavor release measurement from gum model system.  

PubMed

Flavor release from a mint-flavored chewing gum model system was measured by atmospheric pressure chemical ionization mass spectroscopy (APCI-MS) and sensory time-intensity (TI). A data analysis method for handling the individual curves from both methods is presented. The APCI-MS data are ratio-scaled using the signal from acetone in the breath of subjects. Next, APCI-MS and sensory TI curves are smoothed by low-pass filtering. Principal component analysis of the individual curves is used to display graphically the product differentiation by APCI-MS or TI signals. It is shown that differences in gum composition can be measured by both instrumental and sensory techniques, providing comparable information. The peppermint oil level (0.5-2% w/w) in the gum influenced both the retronasal concentration and the perceived peppermint flavor. The sweeteners' (sorbitol or xylitol) effect is less apparent. Sensory adaptation and sensitivity differences of human perception versus APCI-MS detection might explain the divergence between the two dynamic measurement methods. PMID:15612805

Ovejero-López, Isabel; Haahr, Anne-Mette; van den Berg, Frans; Bredie, Wender L P

2004-12-29

170

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

171

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

172

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

173

A chewing gum containing 7.5% sodium hexametaphosphate inhibits stain deposition compared with a placebo chewing gum.  

PubMed

The 2-period, randomized, double-blind, placebo-controlled, crossover study compared the stain-prevention and stain-removal benefit of a chewing gum containing 7.5% sodium hexametaphosphate (measured by digital image analysis) with a placebo chewing gum. The results of this study support that sodium hexametaphosphate delivered from a chewing gum prevents dental stain formation and facilitates stain removal, which leads to a perceptible whitening benefit. The long-term clinical benefits of sodium hexametaphosphate delivered from chewing gum have not been reported in the literature. PMID:15645861

Biesbrock, Aaron R; Walters, Patricia; Bartizek, Robert D

2004-04-01

174

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

175

Phase separation in dextran\\/locust bean gum mixtures  

Microsoft Academic Search

Dextran\\/locust bean gum (LBG) mixtures have been prepared and investigated with respect to their phase separation behaviour. These systems exhibited phase separation at 20 °C, the upper phase, itself biphasic, being enriched with locust bean gum but also containing dextran, whereas the lower phase contained only dextran. This lower phase was a liquid. The upper phase, which did not flow,

Catherine Garnier; Catherine Schorsch; Jean-Louis Doublier

1995-01-01

176

THE GUM, BAYESIAN INFERENCE AND FORWARD AND INVERSE UNCERTAINTY EVALUATION  

Microsoft Academic Search

Uncertainty evaluation is a key element of metrology. In an effort towards bringing uniformity to the evaluation of measurement uncertainty, the Guide to the Expression of Uncertainty in Measurement (GUM, (1)) was developed. The GUM can be regarded as a two-step process, i) the assignment of distributions to input quantities, and ii) the propagation of these distributions to an output

Alistair Forbes; João Sousa

177

Plasma nicotine levels after cigarette smoking and chewing nicotine gum.  

PubMed Central

Plasma nicotine levels were measured over seven hours of smoking cigarettes (1-2 mg nicotine) in a single subject under standardised conditions, and were compared with the levels obtained from chewing-gum containing either 2 mg or 4 mg nicotine. Levels comparable to those resulting from smoking were not obtained with the 2-mg gum, but peak levels on the 4-mg gum averaged 40-1 ng/ml from the third gum onwards compared with 49-2ng/ml after cigarettes. Nicotine was absorbed much more slowly from the gum than from cigarettes. It took 15-30 minutes for the 4-mg gum to raise the plasma nicotine by an average of 11-9 ng/ml compared with an average increase of 27-8 ng/ml within two minutes of completing each cigarette. In a sample of 15 smokers attending a withdrawal clinic the average plasma nicotine concentration while taking 2-mg nicotine chewing-gum was only 10-8 ng/ml compared with 30-4 ng/ml two minutes after smoking a cigarette. Although plasma nicotine levels equivalent to those following cigarette smoking may be obtained by chewing at least 10 pieces of 4-mg nicotine gum daily, the slower rate of absorption may limit its therapeutic value as a substitute for cigarette smoking. PMID:1268547

Russell, M A; Feyerabend, C; Cole, P V

1976-01-01

178

Impact of welan gum on tricalcium aluminate-gypsum hydration  

SciTech Connect

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

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

2012-02-15

179

Gum and deposit formation from jet turbine and diesel fuels  

SciTech Connect

The present paper describes measurements of rates of oxidation and soluble gum formation in both pure hydrocarbons and in mixed hydrocarbon fuels. Some patterns which appear can be explained on the basis of what is known about co-oxidation of hydrocarbon mixtures. The oxidations were conducted in an oil bath at 130/sup 0/C. Gum formation is closely associated with oxidation. The compounds that copolymerize with oxygen to produce polyperoxides require the least amount of oxygen to yield a mg of gum; among other pure hydrocarbons and fuels, the rates of gum formation and oxygen absorption decrease together. The most useful approach to understanding and reducing gum and deposit formation will come through understanding the effects of condensed aromatic and heterocyclic compounds on the oxidation rates of fuels. 4 figures. 4 tables.

Mayo, F.R.; Lan, B.Y.

1983-09-01

180

Gum arabic as a cause of occupational allergy.  

PubMed

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

181

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

182

Seed gum of Stryphnodendron barbatiman (Barbatimao)  

SciTech Connect

Stryphnodendron barbatiman (barbatimao) is a native tree that is found throughout the {open_quotes}Cerrados,{close_quotes} a region of Central Brazil. Plant seeds, on water extraction, furnished 28 g% galactomannan (dry-weight basis), the monosaccharide composition of which (galactose to mannose ratio, 1.0:1.5) fits in the legume heteromannan group. This seed gum, after Sevag deproteinization, still retained 6 g% of associated protein and had a molecular weight of about 1.8 MD on gel filtration. A high intrinsic viscosity (1300 cP) was observed for the polysaccharide sample obtained after reflux of the crushed seeds in 80% aqueous methanol.

Reicher, F.; Leitner, S.C.S.; Fontana, J.D.; Correa, J.B.C.; Sierakowski, M.R. [UFPR, Curitiba (Brazil)

1991-12-31

183

An investigation into the temperature dependence of the rheological synergy between xanthan gum and locust bean gum mixtures  

Microsoft Academic Search

The interaction between xanthan gum (XG) and locust bean gum (LBG) in water has been investigated using texture analysis, thermorheological analysis and high sensitivity differential scanning calorimetry. For the batches of XG and LBG used in the present study and at a total polymer concentration of 1% w\\/v, texture analysis indicated that the greatest synergy occurred at approximately 10% w\\/w

Duncan Q. M. Craig; Amanda Kee; Slobodanka Tamburic; David Barnes

1997-01-01

184

Detection of adulteration of locust bean gum with guar gum by capillary electrophoresis and polarized light microscopy.  

PubMed

Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH3CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH2PO4-20.6 mM Na2B4O7 buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives. PMID:10793850

Flurer, C L; Crowe, J B; Wolnik, K A

2000-01-01

185

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 0.100mol of NaOH, 0.05mol of SMCA, 80% of methanol:water ratio (as % methanol) and liquor:gum ratio (v/w) of 10:1 at 75°C for 60min using 0.03mol (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

186

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

187

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

188

Production of xanthan gum from a chemically defined medium introduction  

SciTech Connect

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

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

1983-02-22

189

What do GUM physicians think should be taught in a modern undergraduate GUM module? A qualitative inquiry.  

PubMed

Traditional undergraduate Genitourinary Medicine (GUM) teaching in the UK concentrated on the management of individual sexually transmitted infections. There is significant variation, however, in the GUM teaching provided by different medical schools today. I undertook a qualitative interview study to gather views of GUM and other sexual health clinicians regarding what should be taught within a modern undergraduate GUM module. Nine GUM Clinicians and two Sexual and Reproductive Health (SRH) clinicians participated in the study; all were directly involved in undergraduate teaching. Semi-structured interviews were conducted with study participants by a single interviewer, focusing on three key topics: their individual opinion regarding important learning outcomes (LOs) for a modern model GUM curriculum, their preferred teaching methods and the total recommended teaching time required. Interviews were audio-recorded with consent and professionally transcribed. Data were analysed by the content analysis method. Interviewees frequently stressed skill and attitudinal LOs, even above knowledge. Recommended important skills included sexual history taking, HIV risk assessment and testing, and male and female genital examination. Recommended attitudinal LOs were developing an open and non-judgemental approach to sexual health issues and understanding sexual well-being to be an important component of general health. Respondents were keen for a mixture of teaching methods, but generally agreed that clinic attendance and experiential learning were beneficial. They preferred that GUM teaching should be delivered in the latter years of the undergraduate curriculum. PMID:25427405

Fernando, I

2014-11-26

190

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

PubMed Central

Background Extrinsic staining of teeth may result from the deposition of a variety of pigments into or onto the tooth surface, which originate mainly from diet or from tobacco use. More recently, clinical studies have demonstrated the efficacy of some chewing gums in removing extrinsic tooth staining. The aim of this study was to assess the effectiveness of two nicotine medicated chewing gums (A and B) on stain removal in an in vitro experiment, when compared with a confectionary whitening chewing gum (C) and human saliva (D). Methods Bovine incisors were stained by alternating air exposure and immersion in a broth containing natural pigments such as coffee, tea and oral microorganisms for 10 days. Stained enamel samples were exposed to saliva alone or to the test chewing gums under conditions simulating human mastication. The coloration change of the enamel samples was measured using a spectrophotometer. Measurements were obtained for each specimen (average of three absorbances) using the L*a*b scale: lightness (L*), red-green (a) and yellow-blue (b). Results Medicated chewing gums (A and B) removed a greater amount of visible extrinsic stain, while the confectionary chewing gum with a whitening claim (C) had a milder whitening effect as evaluated by quantitative and qualitative assessment. Conclusion The tested Nicotine Replacement Therapy (NRT) chewing gums were more effective in the removal of the extrinsic tooth stain. This visible improvement in tooth whitening appearance could strengthen the smokers' motivation to quit smoking. PMID:18694488

Moore, Michael; Hasler-Nguyen, Nathalie; Saroea, Geoffrey

2008-01-01

191

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

192

Rectal absorption and mucosal irritation of rectal gels containing buprenorphine hydrochloride prepared with water-soluble dietary fibers, xanthan gum and locust bean gum  

Microsoft Academic Search

Rectal gels prepared with water-soluble dietary fibers, xanthan gum and locust bean gum, were evaluated as a vehicle for the rectal administration of buprenorphine hydrochloride (BN-HCI) in rabbits. The maximum plasma concentration of buprenorphine (BN) gradually decreased with increase in the gum concentration. The values of the mean residence time (MRT0–2) increased in proportion to increasing gum concentration. The absorption

Kazunori Watanabe; Shigeru Yakou; Kozo Takayama; Koichi Isowa; Tsuneji Nagai

1996-01-01

193

Randomised controlled trial of nicotine chewing-gum  

Microsoft Academic Search

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

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

1982-01-01

194

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

Microsoft Academic Search

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

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

1998-01-01

195

GUM Analysis for TIMS and SIMS Isotopic Ratios in Graphite  

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.

Heasler, Patrick G.; Gerlach, David C.; Cliff, John B.; Petersen, Steven L.

2007-04-01

196

Preformulation studies on grewia gum as a formulation excipient  

Microsoft Academic Search

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

Elijah I. NepBarbara; Barbara R. Conway

197

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

198

Probing the star formation history in the Gum Nebula  

Microsoft Academic Search

We propose UBVRI photometry using CTIO\\/0.9m for the survey of low mass pre-main sequence (PMS) stars around 11 cometary globules (CGs) in the Gum nebula. The Gum nebula is an excellent site to study the influences of high mass (HM) stars on their environment by both terminating and triggering low mass star formation (LMSF). The nebula contains evidence of very

Jinyoung Serena Kim; Frederick M. Walter; Scott J. Wolk

2001-01-01

199

Optimization study of xanthan gum production using response surface methodology  

Microsoft Academic Search

The cultural conditions for xanthan gum production by Xanthomonas campestris were investigated and optimized by response surface methodology, to maximize cell and xanthan production in batch experiments using a synthetic broth (Luria-Bertani plus glucose, LBG) without pH control. The individual and interactive effects of three independent variables (agitation rate (100–600rpm), temperature (25–35°C), time of cultivation (24–72h)) on xanthan gum and

S. K. Psomas; M. Liakopoulou-Kyriakides; D. A. Kyriakidis

2007-01-01

200

Modification of the electrokinetic properties of reversible electrophoresis gels for the separation and preparation of DNA  

Microsoft Academic Search

The effect of adding linear polymers to a novel reversible electrophoretic media was measured. Reversible gels are formed\\u000a using the polyanionic carbohydrate polymer, gellan gum. Gellan gum forms strong stable gels in the presence of divalent cations\\u000a or diamines. The gels are reversible (return to solution) by changing the ionic environment or pH. Gellan gum is an anionic\\u000a polymer, and

Kenneth D. Cole; Carlos M. Tellez; Richard B. Nguyen

1999-01-01

201

The origin of the Gum nebula  

NASA Technical Reports Server (NTRS)

Obsrvations and theoretical investigations of the Gum nebula (GN) since about 1971 are reviewed. Direct observations of the GN, the Vela X supernova remnant (SNR), the Vela pulsar, and other stars in or near the GN are discussed with those of related phenomena such as the radio loops and known SNRs; the emphasis is on studies of the interstellar absorption lines, the evidence for hot gas in the GN, and the extended diffuse emission. The four basic models proposed for the GN are considered: a fossil Stromgren sphere, an old SNR, an H II region, or a superbubble. The GN physical parameters predicted by each model are listed in a table and compared. A minimum explanation which attributes the 36 x 36-deg filamentary structure and the 125-pc radius structure to the action of the stellar winds from Zeta Pup and Gamma-2 Vel (and perhaps the effect of a Vel X supernova explosion 20,000 years ago) is found most appropriate, at least until the questions of the net expansion rate of the GN (about 20 km/sec or about zero?) and the existence of the diffuse emission beyond the filamentary structure are resolved by observations.

Bruhweiler, F. C.; Kafatos, M.; Brandt, J. C.

1983-01-01

202

Evaluation of Release Retarding Property of Gum Damar and Gum Copal in Combination with Hydroxypropyl Methylcellulose  

PubMed Central

The formulations consisting of a hydrophilic and hydrophobic material were investigated for effect on drug-release pattern from the matrices. Gum damar and gum copal being water-insoluble were used to study the efficiency of combined matrices to sustain the release of drug. Hydroxypropyl methylcellulose K100M and diclofenac sodium were used as the hydrophilic material and model drug, respectively. The influence of concentration of hydroxypropyl methylcellulose on drug release pattern of hydrophobic material was determined. The optimum ratio of drug: polymer was found to be 1:1. The hydrophobic:hydrophilic polymer ratio of 75:25 was found to have a similar release pattern as that of marketed formulation. At this ratio, the initial burst-release that occurred in individual hydrophobic matrices was lowered to a great extent. The release of drug was found to follow Higuchi's equation as the concentration of hydrophobic material was increased. The formulations were compared with marketed formulation Voveran SR, and a correlation was drawn accordingly. PMID:23440630

Fulbandhe, V. M.; Jobanputra, C. R.; Wadher, K. J.; Umekar, M. J.; Bhoyar, G. S.

2012-01-01

203

Investigations on interpolymer complexes of cationic guar gum and xanthan gum for formulation of bioadhesive films  

PubMed Central

The present study was aimed at evaluating the possible use of inter polymer complexed (IPC) films of xanthan gum (XG) and cationic guar gum (CGG) for formulating domperidone bioadhesive films. Formation of bonds between –COO¯ groups of XG and –N+(CH3)3 groups of CGG was evident in the FTIR spectra of IPC films. Bioadhesive strength of the films was evaluated employing texture analyser. Water uptake studies indicated swelling to be a function of XG concentration in the interpolymer complexes. The bioadhesive films were found to possess neutral pH. In vitro drug release studies and residence time studies indicated that the film comprising CGG:XG (80:20) released 98% of domperidone in 8 h and exhibited a residence time of approximately 8 h. Enhanced bioavailability of domperidone was observed from bioadhesive films as compared to orally administered conventional tablets. Overall, the findings suggest that IPC films of XG and CGG, exhibiting desired bioadhesive strength and enhanced bioavailability of domperidone, can be prepared. PMID:21589796

Singh, M.; Tiwary, A.K.; Kaur, G.

2010-01-01

204

Nicotine chewing gum as a substitute for smoking.  

PubMed Central

The capacity of nicotine-containing chewing gum to produce plasma nicotine levels comparable to heavy cigarette smoking was tested in 21 subjects. On a fixed schedule of one piece of gum (4 mg nicotine) per hour, the average peak plasma nicotine concentration was 175-7 nmol/l (28-5 ng/ml) compared to 189-3 nmol/l (30-7 ng/ml) obtained from normal ad libitum smoking. Unpleasant side effects were common and in some cases plasma nicotine concentrations were two and even three times as high as with smoking; The chewing gum provided some satisfaction to all but four subjects, but its degree was not related to the concentration of plasma nicotine it produced, neither was there an inverse relation between the plasma nicotine concentration while taking the gum and the subjective sense of missing cigarettesmthis suggests that the capacity of the gum to act as a substitute for smoking is not necessarily related to its capacity to provide nicotine. Flexible dosage dictated by individual needs would probably lower the incidence of side effects and might secure closer approximation to smoking concentrations of plasma nicotine. PMID:322818

Russell, M A; Sutton, S R; Feyerabend, C; Cole, P V; Saloojee, Y

1977-01-01

205

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

206

Effect of Sorbitol, Xylitol, and Xylitol\\/Sorbitol Chewing Gums on Dental Plaque  

Microsoft Academic Search

The effect of sorbitol (SOR), xylitol (XYL), and the mixture XYL\\/SOR in chewing gums on dental plaque was studied in three groups of 7 adults (mean age 22.5 years). A fourth group of habitual users of sucrose-containing gums was used as a control. The study involved a 2-week, no-gum period followed by the use of the polyol gums for 2

E. Söderling; K. K. Mäkinen; C.-Y. Chen; W. Loesche; P.-L. Mäkinen

1989-01-01

207

Chewing-Gum Flavor Affects Measures of Global Complexity of Multichannel EEG  

Microsoft Academic Search

Global complexity of spontaneous brain electric activity was studied before and after chewing gum without flavor and with 2 different flavors. One-minute, 19-channel, eyes-closed electroencephalograms (EEG) were recorded from 20 healthy males before and after using 3 types of chewing gum: regular gum containing sugar and aromatic additives, gum containing 200 mg theanine (a constituent of Japanese green tea), and

T. Yagyu; J. Wackermann; T. Kinoshita; T. Hirota; K. Kochi; I. Kondakor; T. Koenig; D. Lehmann

1997-01-01

208

Nutritional Benefits of Crematogaster mimosae Ants and Acacia drepanolobium Gum for Patas  

E-print Network

Nutritional Benefits of Crematogaster mimosae Ants and Acacia drepanolobium Gum for Patas Monkeys (Erythrocebus patas) are midsized primates that feed extensively on the gum of Acacia drepanolobium and the ants their feeding behavior on ants and gum with that of closely related, sympatric vervets (Chlorocebus pygeryth

209

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

E-print Network

Compared effects of the viscosity of three guar gums on plasma blood glu- cose, insulin) which simulated human food. Six per- cent guar gum of low (G6), medium (G3) or high (Gl) viscosity, the blood glucose responses were similar for all diets. The addition of guar gums to the diets de- creased

Paris-Sud XI, Université de

210

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

E-print Network

Gum arabic glycoprotein contains glycomodules of both extensin and arabinogalactan Abstract Gum arabic glycoprotein (GAGP) is a large molecular weight, hydroxyproline-rich arabinogalactan-protein (AGP) component of gum arabic. GAGP has a simple, highly biased amino acid composition indicating

Kieliszewski, Marcia

211

Variable resistance to Quambalaria pitereka in spotted gum reveal opportunities for disease screening  

E-print Network

Variable resistance to Quambalaria pitereka in spotted gum reveal opportunities for disease the development of spotted gum (Corymbia citriodora subsp. citriodora, C. citriodora subsp. variegata, C. henryi of plantations using spotted gum and Cor- ymbia hybrids. The aim of this study was to determine whether

212

Effects of food gums on viscosities of starch suspensions during pasting  

Microsoft Academic Search

Pasting curves of starches in gum (hydrocolloid) solutions at low concentrations (starch 3.6%, gum 0.4%) were produced with a Brookfield viscometer. Gums produced a variety of effects on viscosities of starches during starch pasting (increase or decrease greatly or slightly or no effect). A viscosity increase before the normal starch pasting temperature was detected for normal maize starch in the

Xiaohong Shi; James N. BeMiller

2002-01-01

213

Spread and development of quambalaria shoot blight in spotted gum plantations  

E-print Network

Spread and development of quambalaria shoot blight in spotted gum plantations G. S. Peggab* , H-grown spotted gum (Corymbia citriodora subsp. citriodora, C. citriodora subsp. variegata, C. henryi and C. maculata) in south-east Queensland, Australia. The results showed that native spotted gums are a primary

214

Nanodisturbances in deformed Gum Metal Mikhail Yu. Gutkin a,*, Toshitaka Ishizaki b  

E-print Network

Nanodisturbances in deformed Gum Metal Mikhail Yu. Gutkin a,*, Toshitaka Ishizaki b , Shigeru experiments have been performed to characterize defect structures in deformed Gum Metal, a special titanium structures in deformed Gum Metal. A theoretical model is suggested describing nanodisturbances as nano- scale

Ovid'ko Ilya A.

215

Dislocation mobility in gum metal -titanium alloy studied via in situ transmission electron microscopy  

E-print Network

Dislocation mobility in gum metal -titanium alloy studied via in situ transmission electron in a transmission electron microscope were carried out on a "Gum Metal" titanium alloy. Conventional dislocation Gum Metals, has been developed.1 These multifunctional alloys are shown to possess "super

Paris-Sud XI, Université de

216

Potential gains through selecting for resistance in spotted gum to Quambalaria pitereka  

E-print Network

Potential gains through selecting for resistance in spotted gum to Quambalaria pitereka G. S. Pegg in mature trees. A spotted gum clonal trial provided the opportunity to investigate the impact eastern Australia and this has seen the rapid expansion of spotted gum plantations in Queensland

217

SPECIES RICHNESS AND ABUNDANCE OF BIRDS IN MT LOFTY RANGES GUM WOODLAND HABITAT: YEAR 2001 SURVEY  

E-print Network

SPECIES RICHNESS AND ABUNDANCE OF BIRDS IN MT LOFTY RANGES GUM WOODLAND HABITAT: YEAR 2001 SURVEY sites in 48 patches of gum woodland from early September 2001 to early January 2002 . Each patch and the year 2000 gum woodland surveys. Its purpose is to place basic processing of the records in the public

Queensland, University of

218

Xylitol Chewing Gums and Caries Rates: A 40-month Cohort Study  

Microsoft Academic Search

Dental caries is a pandemic infectious disease which can affect the quality of life and consumes considerable health care resources. The chewing of xylitol, sorbitol, and even sugar gum has been suggested to reduce caries rates. No clinical study has simultaneously investigated the effectiveness of these gums when compared with a group receiving no chewing gum. A 40-month double-blind cohort

K. K. Makinen; C. A. Bennett; P. P. Hujoel; P. J. Isokangas; K. P. Isotupa; H. R. Pape; PL Makinen

1995-01-01

219

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

220

Evaluation of the Safety of Tara Gum as a Food Ingredient: A Review of the Literature  

Microsoft Academic Search

Tara gum is a potential replacement for locust bean gum for use as a formulation aid, stabilizer, and thickener for food applications. In addition to biochemical and digestibility data, studies assessing the toxicity of tara gum are reviewed. The latter includes three 90-day feeding studies, two in rats and one in dogs; two 2-year feeding studies in rats and one

Joseph F. Borzelleca; Bert N. Ladu; Frederic R. Senti; John L. Egle

1993-01-01

221

76 FR 44811 - Carboxymethyl Guar Gum Sodium Salt and Carboxymethyl-Hydroxypropyl Guar; Exemption From the...  

Federal Register 2010, 2011, 2012, 2013, 2014

...FRL-8880-5] Carboxymethyl Guar Gum Sodium Salt and Carboxymethyl- Hydroxypropyl Guar...residues of carboxymethyl guar gum sodium salt (CAS Reg. No. 39346-76-4) and carboxymethyl-hydroxypropyl...residues of carboxymethyl guar gum sodium salt and carboxymethyl- hydroxypropyl...

2011-07-27

222

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

223

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

224

Gum ghatti-chitosan polyelectrolyte nanoparticles: preparation and characterization.  

PubMed

The objective of the present study was to optimize the interaction between gum ghatti and chitosan to prepare polyelectrolyte nanoparticles using ofloxacin as the model drug. The effect of varying the concentration of gum ghatti, chitosan, Pluronic F-127, and ofloxacin on particle size and entrapment efficiency was studied using central composite experimental design. The optimized calculated parameters were concentrations of gum ghatti (0.12% w/v), chitosan (0.22% w/v), Pluronic F-127 (0.05% w/v), ofloxacin (0.1% w/v), which provided polyelectrolyte nanoparticles of size 121.6 nm and 94.49% entrapment. On screening for antibacterial activity, it was observed that polyelectrolyte nanoparticles had antibacterial activity comparable to the aqueous solution. Further, it was observed that polyelectrolyte nanoparticles released the drug by diffusion through the matrix following Higuchi's square-root kinetics. PMID:23924761

Shelly; Ahuja, Munish; Kumar, Ashok

2013-10-01

225

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

226

Effect of arabic gum and xanthan gum on the stability of pesticide in water emulsion.  

PubMed

The effect of arabic gum (AG) and xanthan gum (XG) on the physicochemical properties of 2% pesticide avermyctin in water emulsions was systematically investigated by measuring creaming stability, droplet size, zeta potential, and rheology. Addition of AG and XG had significant influence on the physicochemical properties of emulsions. Emulsions showed high stability throughout the storage time in the AG concentration range of 0-0.14%. In contrast, addition of XG induced the apparent creaming of emulsion as the XG concentration increased from 0.011 to 0.15%, which might be well explained by the depletion flocculation of droplets. The droplet diameter increased progressively with increasing AG concentration; however, it sharply grew initially with XG concentration and reached a maximum, followed by a gradual decrease. Zeta potential increased gradually as AG concentration was lower than 0.081%, followed by a slight decrease, whereas it reduced dramatically as XG concentration increased from 0.011 to 0.040% and then remained almost unchanged. In the AG concentration range of 0-0.14%, the emulsion exhibited typical Newtonian flow behavior and the viscosity decreased a little. The XG emulsion exhibited Newtonian flow behavior at low XG concentrations (?0.019%), whereas, non-Newtonian flow behavior was displayed at relatively high XG concentrations (>0.019%), wherein viscosity value and yield value increased gradually as XG concentration increased. In addition, the curves of shear stress versus shear rate for XG emulsion and solution were well fitted by a power law model and the Herschel-Bulkley model; the Herschel-Bulkley model fitted much better. The present study would provide useful information for the reasonable application of AG and XG in making stable pesticide emulsion. PMID:21226518

Zhang, Xiaoguang; Liu, Jiexiang

2011-02-23

227

Differentiation of carbohydrate gums and mixtures using fourier transform infrared spectroscopy and chemometrics.  

PubMed

Guar gum, a nonionic galactomannan, is used as an economical thickener and stabilizer in the food industry and is often combined with xanthan, locust bean gum (LBG), or carboxymethylcellulose (CMC) to promote synergistic changes in viscosity or gelling behavior via intermolecular interactions; however, the adulteration of LBG with guar gum is a well-known industrial problem. The ability to identify the purity of gums and concentrations of individual gums in mixtures would be advantageous for quality control in the food industry. Fourier transform infrared spectroscopy (FTIR) methods are rapid and require minimum sample preparation. The objectives of this study were to evaluate the ability of FTIR techniques to (1) differentiate LBG with a variety of mannose/galactose (M/G) ratios, (2) differentiate guar, LBG, tara, and fenugreek gums, (3) differentiate pure guar gum from guar gum mixed with LBG, xanthan gum, or CMC, (4) quantify LBG, xanthan gum, and CMC in guar gum, and (5) quantify guar gum in LBG. Two FTIR methods were used: diffuse reflectance (DRIFT) on powdered gum samples added to KBr at 5%, w/w, and attenuated total reflectance (ATR) on 1%, w/w, gum solutions. Spectra were collected and then analyzed by multivariate statistical procedures (chemometrics). The DRIFT method provided better discrimination and quantitative results than the ATR method. Canonical variate analysis (CVA) of DRIFT spectra (1200-700 cm(-1)) was able to classify LBG with various M/G ratios, pure galactomannans, and pure versus mixtures of gums with 100% accuracy. Quantification of an individual gum in gum mixtures (0.5-15%, w/w) was possible using partial least-squares (PLS) analysis of DRIFT spectra with R2 > 0.93 and using this approach for quantifying guar gum added to LBG resulted in an R2 > 0.99, RMSEC = 0.29, and RMSEP = 3.31. Therefore, the DRIFT FTIR method could be a useful analytical tool for quality control of select gums and gum mixtures used in the food industry. PMID:15826025

Prado, Belén M; Kim, Sol; Ozen, Banu F; Mauer, Lisa J

2005-04-20

228

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 (800MPa). 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

229

Gum and deposit formation from jet turbine and diesel fuels  

SciTech Connect

The rates of oxidation and soluble gum formation in both pure hydrocarbons and mixed hydrocarbon fuels are investigated. A rate equation in terms of rate constants for initiation, propagation, and termination is discussed. A theory based on the coupling of fuels and their primary oxidation products to form products of higher molecular weight is presented.

Mayo, F.R.; Lan, B.Y.

1983-01-01

230

Method for inhibiting gum formation in liquid hydrocarbon mediums  

SciTech Connect

This patent describes a method of inhibiting the formation of gum and sediment in a liquid hydrocarbonaceous medium. It comprises: adding to the medium an inhibiting amount of an alkyl 1,2-dihydroquinoline or polymerized alkyl 1,2-dihydroquinoline.

Reid, D.K.

1990-07-17

231

Improved emulsification performance of corn fiber gum following maturation treatment  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

232

PHENOLIC ACIDS, LIPIDS AND PROTEINS IN CORN FIBER GUM  

Technology Transfer Automated Retrieval System (TEKTRAN)

An arabinoxylan (hemicellulose B), termed "Corn fiber gum" (CFG), is obtained by the alkaline extraction of corn kernel pericarp and/or endosperm fractions of corn fiber (1). Two classes of phytochemicals, hydroxycinnamic acids (p-coumaric and ferulic) and lipids were released, when CFG was hydroly...

233

Investigation of Transport Properties of a New Biomaterials - GUM Mangosteen  

NASA Astrophysics Data System (ADS)

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

Pradhan, Sourav S.; Sarkar, A.

2006-06-01

234

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 ...

235

The effect of chewing gum's flavor on salivary flow rate and pH  

PubMed Central

Background: Chewing sugar-free gums is a convenient way to increase salivary flow. Salivary flow increases in response to both gustatory (taste) and mechanical (chewing) stimuli, and chewing gum can provide both of these stimuli. The aim of this study was to compare the effect of five different flavors of sugar-free chewing gum on the salivary flow rate (SFR) and pH. Materials and Methods: Fifteen dental students volunteered at the same time on six consecutive days, to collect one minute unstimulated saliva. After five minutes, while some volunteers continued to collect only unstimulated saliva, the others asked to start chewing one of the five flavored gums randomly. The flavors were spearmint, cinnamon, watermelon, strawberry, and apple. The whole saliva was collected over time periods of 0 – 1, 1 – 3, and 3 – 6 minutes, and the SFR and pH were also measured. The data were subjected to pair t-test, repeated-measures analysis of variance, and Duncan tests. Results: Compared to the unstimulated rate, all five different flavored gums significantly increased the SFR within six minutes. Although the flow rate peaked during the first minute of stimulation with all five products, it reduced gradually, but still remained above the unstimulated saliva, after six minutes. In the first minute, the strawberry-flavored gums showed the highest weight, yet, it only induced a significantly higher SFR compared to the cinnamon-flavored gums. During one to three minutes, strawberry and apple-flavored gums showed significantly higher SFR, respectively, compared to cinnamon-flavored gums. There were no significant differences in the flow rates elicited by each flavored gum through the three-to-six minute interval, although the spearmint-flavored gums induced slightly higher SFR. Only the spearmint and cinnamon-flavored gum significantly increased the salivary pH. Conclusion: Gum flavor can affect the SFR and special flavors may be advised for different individuals according to their oral conditions. PMID:23372599

Karami-Nogourani, Maryam; Kowsari-Isfahan, Raha; Hosseini-Beheshti, Mozhgan

2011-01-01

236

Property of cellular silicone from high-vinyl silicone gums as a function of porosity (referenced to SE54 gum). [Density, porosity, deflection, compression set  

SciTech Connect

We have established the load-deflection properties of cushions from the high methylvinylsiloxane (MVS) content gums, L97KVB-0.7, MN97KVB-0.7, and L60VB-0.7, as a function of cushion porosity. These properties are referenced to the properties of cushions from General Electric's (GE) SE54 gum which has considerably less MVS. The higher MVS gums produce considerably stiffer cushions. We have also evaluated the confined compression set of these various porosity cushions. There is no pattern for set as a function of porosity. Set is reduced at the higher MVS contents. We have established the densities of the cured solid elastomers (3219) from the four silicone gums. We have also calculated a linear relationship between porosity of the cushions and the wt % of urea temporary filler in the molding compound for the 97-type gums and L60 gum. L97KVB-0.7 and MN97KVB gums produce cushions with similar but not exactly the same load-deflections and sets, and are alike in their correlations of porosity with urea loading. L60VB-0.7 produces a softer cushion and probably has less set than the 97-type gums at 0.7% MVS. 13 figures, 36 tables.

Cady, W.E.; Jessop, E.S.; McKinley, B.M.

1982-08-20

237

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

Microsoft Academic Search

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

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

2004-01-01

238

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

PubMed

Xanthan gum is a complex exopolysaccharide produced by the plant-pathogenic bacterium Xanthomonas campestris pv. campestris. It consists of D-glucosyl, D-mannosyl, and D-glucuronyl acid residues in a molar ratio of 2:2:1 and variable proportions of O-acetyl and pyruvyl residues. Because of its physical properties, it is widely used as a thickener or viscosifier in both food and non-food industries. Xanthan gum is also used as a stabilizer for a wide variety of suspensions, emulsions, and foams. This article outlines aspects of the biochemical assembly and genetic loci involved in its biosynthesis, including the synthesis of the sugar nucleotide substrates, the building and decoration of the pentasaccharide subunit, and the polymerization and secretion of the polymer. An overview of the applications and industrial production of xanthan is also covered. PMID:9763683

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

1998-08-01

239

Locust bean gum: Exploring its potential for biopharmaceutical applications.  

PubMed

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

2012-07-01

240

Chewing gum and lozenges as delivery systems for noscapine.  

PubMed

Chewing gum and lozenges were evaluated as delivery systems for noscapine with the aim of developing improved antitussive preparations. The formulations studied were prepared with both the water-soluble hydrochloride salt of noscapine and with the poorly soluble embonate salt and noscapine free base. The release characteristics of the preparations were evaluated both in vitro and in vivo, and their taste properties examined. Only the formulations containing noscapine base were without any appreciable taste. Chewing gum containing this compound showed, however, a low level of drug release both in vitro and in vivo and is therefore not a suitable dosage form. Only a lozenge formulation containing noscapine base fulfilled the requirements of taste acceptability and adequate release properties. PMID:1781914

Jensen, L N; Christrup, L L; Menger, N; Bundgaard, H

1991-01-01

241

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

242

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

243

Use of hydrophilic natural gums in formulation of sustained-release matrix tablets of tramadol hydrochloride  

Microsoft Academic Search

The objective of this work was to develop matrix sustained-release tablets of highly water-soluble tramadol HCl using natural\\u000a gums (xanthan [X gum] and guar [G gum]) as cost-effective, nontoxic, easily available, and suitable hydrophilic matrix systems\\u000a compared with the extensively investigated hydrophilic matrices (ie, hydroxypropyl methylcellulose [HPMC]\\/carboxymethyl cellulose\\u000a [CMC] with respect to in vitro drug release rate) and hydration rate

Jaleh Varshosaz; Naser Tavakoli; Fatemeh Kheirolahi

2006-01-01

244

Evaluation of the flow properties of xanthan gum solution  

SciTech Connect

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

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

1981-02-01

245

Rheological characterisation of ?-carrageenan\\/locust bean gum mixtures  

Microsoft Academic Search

The rheological behaviour of the binary system of ?-carrageenan and locust bean gum (LBG) has been characterised using both compression and shear measurements. Slip effects caused by syneresis of the ?-carrageenan during dynamic shear measurements were eliminated through the use of pre-formed gels glued between parallel plates. The improved measurement system yielded very high G? values of the order 10,000–30,000Pa

Y Chen; M.-L Liao; D. V Boger; D. E Dunstan

2001-01-01

246

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

247

Ipomoea turpethum seeds: a potential source of commercial gum  

Microsoft Academic Search

A non-ionic water-soluble galactomannan, having a galactose and mannose in 1:2 molar ratio was isolated from endosperm of the seeds. Seed gum has a branched structure consisting of a linear chain of ? (1?4) linked mannopyranosyl units with d-galactose side chains attached through ? (1?6) linkage to the main chain, a fundamental structural pattern found in other seed galactomannans like

Vandana Singh; Vasundhara Srivastava; Meenakshi Pandey; Rupali Sethi; Rashmi Sanghi

2003-01-01

248

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

249

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

250

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

SciTech Connect

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

Schneider, J.W.

1986-06-01

251

Pharmacognostic studies of gums collected from aprocot trees growing in Armenia and perspectives of their use.  

PubMed

Plant polysaccharides are widely used in the food and confectionary industries, as an emulsifier, flavour encapsulator, and thickening agent. The apricot tree has a gum that oozes out in the spring and it seems to be a lot like gum Arabic. Gums collected from apricot trees growing in Armenia (RA) are considered as exudates of ecological significance. Besides, in food industry it can entirely replace the more expensive gum Arabic as well as its synthetic derivatives. Periodically organized resource potential studies in the regions of RA gives the opportunity to have an exact notion of biological and utilized resources of gums as a natural exudates of cultivated apricot trees of the country. The study was conducted on gums collected from the apricot trees of Armavir region (Armavir, Edjmiatsin, Baghramyan) that were purified by general physical methods without any chemical or enzymatic influence. According to obtained results--from one apricot tree was collected 54.15+/- 4.41 g/m(2), the biological resource of apricot gum was 45 ton. We also determined the quantities of Mg, K and Ca in apricot gum by atomic--absorptive method (Mg - 18 mg/kg; Ca - 5.8 mg/kg; K - 15.7 mg/kg). The study results also revealed that addition of gummi armeniaca increases the yeast biomass up to 55%. According to above mentioned and the great resources of raw material of apricot tree gum it can be approved its usage in the food industry in Armenia. PMID:19996509

Chichoyan, N

2009-11-01

252

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

253

Process for the selective hydrogenation of gasolines comprising both gum-generating compounds and undesirable sulfur compounds  

SciTech Connect

Unsaturated gasolines of both high mercaptan or hydrogen sulfide content and high gum-generator content are hydrogenated first over a palladium catalyst and then over a nickel catalyst. Resultant unsaturated gasolines are sweet and have low gum generator content.

Cosyns, J.; Derrien, M.

1980-06-17

254

Combined Use of Nicotine Patch and Gum in Smoking Cessation: A Placebo-Controlled Clinical Trial  

Microsoft Academic Search

Background. Smoking is considered as an addiction to nicotine for most subjects consuming 10 cigarettes or more per day. Hence, nicotine replacement therapy by way of gum, patch, or spray has been advocated. The rationale of this study is to evaluate the possible beneficial effects of adding nicotine gum to the routine of subjects using the nicotine patch. The effect

M. Kornitzer; M. Boutsen; M. Dramaix; J. Thijs; G. Gustavsson

1995-01-01

255

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

256

Effectiveness of nicotine patch and nicotine gum as individual versus combined treatments for tobacco withdrawal symptoms  

Microsoft Academic Search

Nicotine gum and transdermal nicotine have been shown to relieve withdrawal and double success rates over placebo in trials of smoking cessation. This study tested whether combining the two methods would relieve withdrawal more effectively compared to either treatment alone. Twenty-eight smokers served as their own controls in each of four conditions: active gum + active patch (double active), active

K. O. Fagerström; N. G. Schneider; E. Lunell

1993-01-01

257

Genome Sequence of Xanthomonas campestris JX, an Industrially Productive Strain for Xanthan Gum  

PubMed Central

Xanthomonas campestris JX, a soil bacterium, is an industrially productive strain for xanthan gum. Here we present a 5.0-Mb assembly of its genome sequence. We have annotated 12 coding sequences (CDSs) responsible for xanthan gum biosynthesis, 346 CDSs encoding carbohydrate metabolism, and 69 CDSs related to virulence, defense, and plant disease. PMID:22887662

Tao, Fei; Wang, Xia; Ma, Cuiqing; Yang, Chunyu; Tang, Hongzhi; Gai, Zhonghui

2012-01-01

258

Preliminary study of Anacardium occidentale gum as binder in formulation of paracetamol tablets  

Microsoft Academic Search

An attempt was made to investigate the binding efficacy of cashew nut tree gum in tablet formulation in comparison with standard binders such as acacia and polyvinyl pyrrolidone (PVP K-30). The paracetamol granules were prepared with different concentration of the gum as binder by wet granulation method. The granules were evaluated and found to be satisfactory for preparing compressed tablets.

K. Gowthamarajan; G. Kanaka Phani Kumar; Narayan Babulal Gaikwad; B. Suresh

2011-01-01

259

Interactions of native and acetylated pea starch with yellow mustard mucilage, locust bean gum and gelatin  

Microsoft Academic Search

The interactions of yellow mustard mucilage, locust bean gum and gelatin with native and acetylated pea starch were studied by a Brabender viscograph, a Bohlin rheometer and differential scanning calorimetry (DSC). In the presence of mustard mucilage or locust bean gum, the onset temperature of the viscogram shifted to lower temperatures, whereas the final viscosities of the pastes increased markedly

Hua Liu; N. A. Michael Eskin

1998-01-01

260

Twenty-four week maintenance treatment of cigarette smoking with nicotine gum, clonidine and naltrexone  

Microsoft Academic Search

This research study investigated the effect of nicotine gum, clonidine, and naltrexone, in the maintenance treatment of cigarette smoking. In a double blind study, 171 nicotine-dependent male subjects who met DSM-IV criteria for nicotine dependence and smoking 10 cigarettes or more per day, were allocated randomly to three equal groups of 57. Subjects received nicotine gum, clonidine, or naltrexone over

Jamshid Ahmadi; Hamid Ashkani; Mojtaba Ahmadi; Nahid Ahmadi

2003-01-01

261

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

262

Effect of nicotine chewing gum on smoking behaviour and as an aid to cigarette withdrawal.  

PubMed Central

In a double-blind, placebo-controlled, crossover trial the effect of 2-mg nicotine chewing gum was studied in 43 smokers when they were smoking as inclined and when they were trying to stop smoking. Although 70% of the smokers stopped smoking during treatment, only 23% were still abstinent after one year. The effect of the nicotine, though significant, was small compared with the overall reduction in smoking. When the subjects were smoking as inclined cigarette consumption was reduced by an average of 37% on the nicotine gum compared with 31% on placebo gum, while avergage carboxyhaemoglobin (COHb) levels were reduced by 26% and 15% on the active and placebo gums respectively. When subjects tried to stop smoking there was a further considerable reduction in cigarette consumption, but no longer any difference between the two gums. Nevertheless, average COHb was still lower on the active gum. Plasma nicotine levels on the nicotine gum averaged only 10-7 ng/ml compared with 27-4 ng/ml after smoking. Better results could be expected with 4-mg nicotine gums. PMID:779926

Russell, M A; Wilson, C; Feyerabend, C; Cole, P V

1976-01-01

263

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

Microsoft Academic Search

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

N. Garti; Y. Slavin; A. Aserin

1999-01-01

264

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...

265

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...

266

GUM: a portable parallel implementation of Haskell K Hammond JS Mattson Jr \\Lambda AS Partridge y SL Peyton Jones  

E-print Network

GUM: a portable parallel implementation of Haskell K Hammond JS Mattson Jr \\Lambda AS Partridge y,mattson,ap,simonpj,trinderg@dcs.glasgow.ac.uk September 4, 1995 Abstract GUM is a portable, parallel implementation of the Haskell functional language which has been publicly released with version 0.26 of the Glasgow Haskell Compiler (GHC). GUM is message

Jones, Simon Peyton

267

GUM: a portable parallel implementation of Haskell K Hammond JS Mattson Jr AS Partridge y SL Peyton Jones  

E-print Network

GUM: a portable parallel implementation of Haskell K Hammond JS Mattson Jr AS Partridge y SL Peyton,mattson,ap,simonpj,trinderg@dcs.glasgow.ac.uk September 4, 1995 Abstract GUM is a portable, parallel implementation of the Haskell functional language which has been publicly released with version 0.26 of the Glasgow Haskell Compiler (GHC). GUM is message

Trinder, Phil

268

GUM: a portable parallel implementation of Haskell PW Trinder K Hammond JS Mattson Jr \\Lambda AS Partridge y  

E-print Network

GUM: a portable parallel implementation of Haskell PW Trinder K Hammond JS Mattson Jr \\Lambda,kh,simonpjg@dcs.glasgow.ac.uk Abstract GUM is a portable, parallel implementation of the Haskell functional language. Despite sustained research interest in parallel functional programming, GUM is one of the first such systems to be made

Jones, Simon Peyton

269

Biosorption of nickel and total chromium from aqueous solution by gum kondagogu ( Cochlospermum gossypium): A carbohydrate biopolymer  

Microsoft Academic Search

Gum kondagogu (Cochlospermum gossypium), an exudates tree gum from India was explored for its potential to decontaminate toxic metal ions in aqueous solution. The toxic metal ions nickel and total chromium biosorption capacity of the gum kondagogu were studied in the batch experimental mode. The optimum conditions of biosorption were determined by investigating pH, contact time, and initial metal ion

V. T. P. Vinod; R. B. Sashidhar; B. Sreedhar

2010-01-01

270

76 FR 20666 - Streptomyces Strain K61, and Wood Oils and Gums; Registration Review Final Decisions; Notice of...  

Federal Register 2010, 2011, 2012, 2013, 2014

...FRL-8867-3] Streptomyces Strain K61, and Wood Oils and Gums; Registration Review Final...305-5614, gross.anna@epa.gov. Wood Oils and Gums.......... EPA-HQ-OPP-2009-0258...borne damping off and early root rot. 2. Wood Oils and Gums (3150). The Wood...

2011-04-13

271

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.

Team, University C.

2007-12-12

272

Gum and deposit formation from jet-turbine and diesel fuels at 130C  

SciTech Connect

The ultimate objective of this work is to devise an accelerated test to compare rates of soluble gum and deposit formation from jet-turbine and diesel fuels in storage and of hard deposits in engines. This paper describes rates of oxygen absorption and gum formation in air at 130 C. For a single fuel or hydrocarbon, the rate of gum formation is closely proportional to the oxygen absorbed, even when this rate varies with purification and additives. In general, pure hydrocarbons absorb oxygen much faster than the fuels, but the fuels and 2-ethylnaphthalene give more gum for the oxygen absorbed than the other pure hydrocarbons. Gum has two main sources; one appears to be associated with the chain termination mechanism in oxidation, the other coupling of fuel molecules in the absence of oxygen. Other possibilities are discussed.

Mayo, F.R.; Lan, Bosco Y.

1986-01-01

273

Gum and deposit formation in diesel fuels. Final report, 1984-1988  

SciTech Connect

The authors examined two aspects of the stability of diesel fuels in storage: the formation of sediments in suspension, which subsequently clog filters, and the formation of soluble gum, which passes the filters but then forms hard deposits on hot engine parts. Research on fuel stability at SRI during the last 6 years has shown that soluble gum appears first on storage, and then part of it grows into sediment. If the oxidation mixture is agitated gently, the precipitating gum grows on the surface gum, and no loose sediment is formed. Three mechanisms of gum formation were distinguished: (1) a process intimately associated with chain propagation and termination during oxidation, (2) a coupling of fuel molecules by decomposing peroxides in the absence of oxygen, and (3) a condensation of naphthols and aldehydes from the oxidation of alkylnaphthalenes. The polymeric oxidation products from a JP-8 fuel are shown to be largely responsible for deposits in the Jet Fuel Thermal Oxidation Tester (JFTOT).

Mayo, F.R.; Mill, T.

1988-05-15

274

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

PubMed

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

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

2014-10-01

275

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

NASA Astrophysics Data System (ADS)

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

Singh, Baljit; Sharma, Vikrant

2013-11-01

276

Sulfation of Aegle marmelos gum: synthesis, physico-chemical and functional characterization.  

PubMed

The present investigation was aimed at optimizing the conditions for preparing sulfated derivative of gum obtained from partially ripe fruits of Aegle marmelos. Elemental analysis, FTIR-ATR and NMR studies confirmed successful sulfation. The ratio of chlorosulfonic acid to pyridine exerted maximum influence on the degree of substitution followed by reaction temperature and reaction time. The sulfated derivative showed higher swelling in both acidic and alkaline pH as compared to unmodified gum. It also possessed higher negative zeta potential, higher viscosity, work of shear, firmness, consistency, cohesiveness and index of viscosity as compared to both unmodified gum as well as sodium alginate. Sulfated derivative was superior to unmodified gum and sodium alginate in terms of antimicrobial and anticoagulant activity. The sulfated sample appears to be a potential substitute over the unmodified gum sample and sodium alginate for modulating physicochemical properties of food and drug release dosage forms. PMID:23399204

Jindal, Manish; Rana, Vikas; Kumar, Vineet; Singh, Ram S; Kennedy, John F; Tiwary, Ashok K

2013-02-15

277

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

278

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

279

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

280

Young stars of low mass in the Gum nebula  

NASA Technical Reports Server (NTRS)

Observations are presented for four recently formed stars in the vicinity of the Gum nebula which are heavily obscured by surrounding dust and are associated with small reflection nebulae. HH46 is the only currently active star of the sample, and it is found to have a spectral type in the range of late G-early K, with superimposed emission lines of H-alpha, Ca II, Fe I, Fe II, and weak He I at near zero velocities. It is suggested that the observed scenario of low-mass stars in an older massive star environment may be analogous to the circumstances surrounding the birth of the sun.

Graham, J. A.; Heyer, Mark H.

1989-01-01

281

Young stars of low mass in the Gum nebula  

SciTech Connect

Observations are presented for four recently formed stars in the vicinity of the Gum nebula which are heavily obscured by surrounding dust and are associated with small reflection nebulae. HH46 is the only currently active star of the sample, and it is found to have a spectral type in the range of late G-early K, with superimposed emission lines of H-alpha, Ca II, Fe I, Fe II, and weak He I at near zero velocities. It is suggested that the observed scenario of low-mass stars in an older massive star environment may be analogous to the circumstances surrounding the birth of the sun. 53 refs.

Graham, J.A.; Heyer, M.H. (Carnegie Institution of Washington, Washington, DC (USA))

1989-06-01

282

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.

283

Gum and deposit formation from jet turbine and diesel fuels  

SciTech Connect

The objective of this work is to determine the chemistry of deposit formation in hot parts of jet turbine and diesel engines and, thus, to predict and prevent deposit formation. Previous work in the field has been extensive, but a real understanding of deposit formation has been elusive. Work at SRI started on the basis that deposit formation from fuels must take place stepwise and is associated with autoxidation and the hydroperoxide produced. More recent work showed that in the absence of dissolved oxygen, higher temperatures are required for deposit formation. A recent report indicated that gum and deposit formation proceed mainly through oxidation products of the parent hydrocarbon, coupling of these products to dimeric, trimeric and higher condensation products (partly or wholly by radicals from hydroperoxides) and precipitation of insoluble products. The authors know of no information on how these first precipitates are converted to the ultimate, very insoluble, carbonaceous materials that cause engine problems. The present paper describes measurements of rates of oxidation and soluble gum formation in both pure hydrocarbons and mixed hydrocarbon fuels. Some patterns appear that can be largely explained on the basis of what is known about co-oxidations of hydrocarbon mixtures.

Mayo, F.R.; Lan, B.Y.

1983-09-01

284

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

285

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

286

[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

287

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

288

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

289

Guar gum coupled microscale ZVI for in situ treatment of CAHs: continuous-flow column study.  

PubMed

A column study was performed under in situ conditions to evaluate to which extend the inactivation of the microscale zerovalent iron (mZVI) by guar gum occurs under continuous flow conditions. Five aquifer containing columns were set up under different conditions. Efficient removal of trichloroethene was observed for the column amended by mZVI. Stabilization of the mZVI with guar gum led to slightly reduced activity. More reduced reactivity was observed in the poisoned column containing guar gum stabilized mZVI. This confirms that soil microorganisms can degrade guar gum and that subsequent removal of the oligosaccharides by the groundwater flow (flushing effect) can reactivate the mZVI. After more than six months of continuous operation the columns were dismantled. DNA-based qPCR analysis revealed that mZVI does not significantly affect the bacterial community, while guar gum stabilized mZVI particles can even induce bacterial growth. Overall, this study suggests that the temporarily decreased mZVI reactivity due to guar gum, has a rather limited impact on the performance of in situ reactive zones. The presence of guar gum slightly reduced the reactivity of iron, but also slowed down the iron corrosion rate which prolongs the life time of reactive zone. PMID:24333711

Velimirovic, Milica; Simons, Queenie; Bastiaens, Leen

2014-01-30

290

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

291

Native and structurally modified gum arabic: Exploring the effect of the gum's microstructure in obtaining electroactive nanoparticles.  

PubMed

Electroactive nanoparticles combining gum arabic (GA) and polyaniline (PANI) were prepared by chemical synthesis. The gum consists of highly branched anionic polysaccharides with some protein content. GA was structurally modified by Smith controlled degradation, in order to reduce its degree of branching (GAD), aiming the elucidation of the relationship between the structure and the properties of complex polysaccharides. The modification was studied by SEC, GC-MS, (13)C NMR and colorimetric methods. GAD has lower molecular mass, lower degree of branching and lower uronic acid content. Besides it is enriched in galactose and protein when compared with GA. The obtained composites (GA-PANI and GAD-PANI) were thoroughly characterized. Although the use of both polysaccharides (GA and GAD) produced highly stable electroactive nanoparticles, the best combination of properties was achieved for GA-PANI. The sample GAD was not able to prevent the occurrence of crosslinking between PANI chains, possibly due to its lower microstructural complexity which diminishes the occurrence of hydrogen bonds between the polymers. PMID:25563942

Cornelsen, Patricia A; Quintanilha, Ronaldo C; Vidotti, Marcio; Gorin, Philip A J; Simas-Tosin, Fernanda F; Riegel-Vidotti, Izabel C

2015-03-30

292

Effect of xanthan gum and guar gum on in situ gelling ophthalmic drug delivery system based on poloxamer-407.  

PubMed

The aim of this investigation was to develop a novel in situ gelling formulation based on poloxamer-407 (PM) for the sustained release of an ophthalmic drug. In an attempt to reduce the concentration of PM without compromising the in situ gelling capability and also to increase the drug release time, xanthan gum (XG) and guar gum (GG) were added into PM to develop different formulations. At concentrations of 18% and above, the PM was able to undergo sol-gel transition below body temperature. It was found that XG and GG at a weight ratio of 3:7 were able to convert PM solution into gel below body temperature at PM concentrations below 18%. Both the in vitro and in vivo studies indicated that the PM with an XG-GG combination had a better ability to retain the drug than PM itself. The results indicated that the developed in situ gelling formulations containing PM with XG-GG may be a better alternative than a conventional eye drop. PMID:23988556

Bhowmik, Manas; Kumari, Puja; Sarkar, Gunjan; Bain, Mrinal Kanti; Bhowmick, Biplab; Mollick, Md Masud Rahaman; Mondal, Dibyendu; Maity, Dipanwita; Rana, Dipak; Bhattacharjee, Debashis; Chattopadhyay, Dipankar

2013-11-01

293

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

294

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.

Stern, David

295

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

296

Application and Characterization of Gum from Bombax buonopozense Calyxesas an Excipient in Tablet Formulation  

PubMed Central

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

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

2012-01-01

297

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

298

Ethephon-Induced Gummosis in Sour Cherry (Prunus cerasus L.) : II. Flow Characteristics of Gum Solutions.  

PubMed

Flow of sour cherry (Prunus cerasus L. cv. Montmorency) gum solutions through a glass capillary was Newtonian for pressure gradients from 0 to 1.8 megapascals per meter, and hydraulic conductance was inversely proportional to solution viscosity in this range. However, flow became plastic at pressure gradients above 1.8 megapascals per meter, resulting in a decrease in solution viscosity. The magnitude of this effect diminished as gum concentration increased. Flow of water, a solution of the component sugar monomers of sour cherry gum, and sucrose solutions remained Newtonian over the entire pressure gradient range examined (0-4 megapascals per meter). Plastic flow of gum solutions in the vessels of intact sour cherry shoots is possible under pressure gradients induced by transpiration when high resistance to flow occurs over short distances. PMID:16662533

Olien, W C; Bukovac, M J

1982-08-01

299

Comparison of nicotine chewing-gum and psychological treatments for dependent smokers.  

PubMed Central

The results of using nicotine chewing-gum to treat dependent smokers attending a withdrawal clinic were compared with the results of psychological treatment. At one-year follow-up 26 (38%) out of 69 people who received nicotine gum were abstinent compared with seven (14%) out of 49 who received psychological treatment (p < 0.01). Abstinence was confirmed by the measurement of carboxyhaemoglobin concentrations or expired air carbon monoxide. Blood nicotine concentrations when patients used the gum averaged half the smoking values, and side effects were few. Addiction occurred in only two subjects. Thus nicotine chewing-gum is a useful aid to giving up smoking and is probably acceptable even for people with cardiovascular disease. PMID:7427329

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

1980-01-01

300

Scatter broadening of pulsars in the direction of the Gum nebula  

E-print Network

We have measured the scatter broadening of pulsars in the direction of the Gum nebula. For the first time, our observations show clear variations of scattering properties across the Gum nebula. The IRAS-Vela shell is shown to be a high scattering region. Our revised estimations of distances to these pulsars are consistently less by a factor of 2--3, which has very important consequences for the deduced values of radio luminosity and transverse velocity of pulsars.

Ramachandran, D M R

2001-01-01

301

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

302

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

SciTech Connect

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

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

1987-07-01

303

Scatter broadening of pulsars in the direction of the Gum nebula  

E-print Network

We have measured the scatter broadening of pulsars in the direction of the Gum nebula. For the first time, our observations show clear variations of scattering properties across the Gum nebula. The IRAS-Vela shell is shown to be a high scattering region. Our revised estimations of distances to these pulsars are consistently less by a factor of 2--3, which has very important consequences for the deduced values of radio luminosity and transverse velocity of pulsars.

D. Mitra; R. Ramachandran

2001-05-04

304

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

305

Rheological study of xanthan and locust bean gum interaction in dilute solution  

Microsoft Academic Search

An oscillatory capillary rheometer was used to investigate visco-elastic properties of xanthan and locust bean gum (LBG) blends in dilute solution. Gums were evaluated for intrinsic viscosity and the elastic component. Molecular conformation of the complex of xanthan–LBG was assessed by the power law and the Huggins equations. A 60% xanthan–40% LBG blend exhibited the strongest attraction between xanthan and

J. Higiro; T. J. Herald; S. Alavi

2006-01-01

306

Rheological study of xanthan and locust bean gum interaction in dilute solution: Effect of salt  

Microsoft Academic Search

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 complex was assessed by the power-law and Huggins equations. Addition of any of the three salts reduced

J. Higiro; T. J. Herald; S. Alavi; S. Bean

2007-01-01

307

Rheology and microstructure of Ca and Na K-carrageenan and locust bean gum gels  

Microsoft Academic Search

The viscoelastic and microstructural influences of 0.1-0.6% locust bean gum on 0.5 or 1.0% ?-carrageenan gels, in different ionic environments, have been studied using small deformation oscillatory measurements and transmission electron microscopy (TEM). The results from the Theological measurements showed synergistic effects in the storage modulus, G', as locust bean gum, of two different mannose to galactose ratios (3 and

Leif Lundin; Anne-Marie Hermansson

1997-01-01

308

Effect of xanthan and locust bean gums on the gelling properties of myofibrillar protein  

Microsoft Academic Search

Protein-hydrocolloids interactions play an important role on textural and mechanical properties of foods. The objective of this work was to evaluate the effect of xanthan and locust bean gums on the gelling ability of myofibrillar proteins at different levels of calcium addition. Surimi was supplemented with xanthan (X) and locust bean (LB) gums at different X\\/LB ratios: 0.00\\/1.00, 0.25\\/0.75, 0.50\\/0.50,

J. A. Ram??rez; M. Barrera; O. G. Morales; M. Vázquez

2002-01-01

309

Rheological characterization of experimental dairy creams formulated with locust bean gum (LBG) and ?-carrageenan combinations  

Microsoft Academic Search

The influence of the locust bean gum (LBG)–?-carrageenan stabilizer combination on the rheology of dairy creams was analyzed. A central composite factorial design was used to choose the LBG–?-carrageenan ratio, the weight fraction of each gum ranging from 0 to 0.1g per 100g cream. Cross’ rheological model was closely fitted to describe the flow curves of the samples and Cross

M. M. Camacho; N. Martínez-Navarrete; A. Chiralt

2005-01-01

310

Microstructure of acid–induced skim milk–locust bean gum–xanthan gels  

Microsoft Academic Search

The microstructure of acid skim milk gels (14% w\\/w milk protein low heat powder) with or without addition of locust bean gum (LBG), xanthan gum (XG) and LBG\\/XG blends was determined by transmission electron microscopy (TEM), phase-contrast light microscopy (PCLM) and scanning electron microscopy (SEM). Three polysaccharide concentrations (0.001%, 0.02% and 0.1%, w\\/w) were used for binary mixtures. In the

C. Sanchez; R. Zuniga-Lopez; C. Schmitt; S. Despond; J. Hardy

2000-01-01

311

In vitro evaluation of Moringa oleifera gum for colon-specific drug delivery  

PubMed Central

Background: Moringa gum obtained from stem of the plant Moringa oleifera Lam. belonging to family Moringaceae. Number of naturally occurring polysaccharides obtained from plant (guar gum, inulin), animal (chitosan, chondrotin sulphate), algal (alginates) or microbial (dextran) origin. Objective: The present study was evaluated Moringa oleifera gum as a carrier for colon specific drug delivery using in vitro drug release studies. Materials and Methods: Six formulations of curcumin were prepared using varying concentration of Moringa oleifera gum containing 50 mg curcumin by wet granulation method. Tablets were subjected for evaluation by studying the parameter like hardness, friability, drug content uniformity and in vitro drug release study. Hardness was found to be in the range of 5.5 to 7.3 kg/cm2, the percentage friability was in the range of 0.60 to 0.89%, and tablet showed 98.99% to 99.89% of the labeled amount of curcumin indicating uniformity in drug content. Results and Discussion: In vitro drug release study was performed using simulated stomach, intestinal and colonic fluid. The susceptibility of Moringa gum to colonic bacteria was also assessed using drug release study with rat caecal contents. 30% Moringa gum containing formulation (F-3) was shown better drug released that is 90.46%, at the end of 24 h of dissolution study in the presence of rat caecal contents in comparison to 40% Moringa gum containing formulation (F-4) that was 78.03%. Conclusion: The results illustrate the usefulness of Moringa olefera gum as a potential carrier for colon-specific drug delivery. PMID:23071960

Singhal, Anil Kumar; Jarald, Edwin E; Showkat, Ahmad; Daud, Anwar

2012-01-01

312

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

313

The development of immunoassays to identify and quantify species source of gum arabic.  

PubMed

Gum arabic from Acacia senegal is commonly used as an additive in foodstuffs. Adulteration of gum arabic by other gums is a potential problem for reasons of safety and quality. This study aimed to develop and evaluate the use of enzyme-linked immunosorbent assays (ELISAs) for the detection of potential adulterants of gum arabic. Indirect competitive ELISAs (IC-ELISAs) were developed using the monoclonal antibodies SY CC7 (A. senegal), SY HH3 (Acacia seyal), and SY J1A1 (Combretum erythrophyllum). All IC-ELISAs had a working range of 0.005-10 mg/mL. The antibodies used were tested using the IC-ELISAs for cross-reactivity with other Acacia species and other gums. The antibodies were very specific for their respective antigens. Significant cross-reactivity was found for SY CC7 (between A. senegal and A. melliferae) and SY J1A1 (between C. erythrophyllum and A. seyal). The IC-ELISA was adapted further to test confectionery samples for the presence of gum arabic, which was successful, although recovery rates were reduced. Both IC- and plate trapped antigen ELISA (PTA-ELISA) formats were able to distinguish an adulterated sample of gum arabic when blended with either A. seyal or C. erythrophyllum. The PTA-ELISA was more sensitive for A. seyal than the IC-ELISA, but both were equally sensitive for C. erythrophyllum. The results suggest that the antibodies SY CC7, SY HH3, and SY J1A1 could be used in combination with each other for the detection of potential adulterants of A. senegal and the detection of gum arabic in foodstuffs. PMID:15612759

Ireland, H Elyse; Clutterbuck, Andy; Cloquet, Jean-Phillipe; Thurston, Milo I; Williams, Peter A; Cronk, Quentin C; Dewey, F Molly; Williams, John H H

2004-12-29

314

Gum and deposit formation from jet-turbine and diesel fuels at 100 C  

SciTech Connect

Rates of oxidation and gum formation for six hydrocarbons, three jet-turbine fuels and three diesel fuels have been measured at 100 C in the presence of t-Bu2O2 tert-butyl-peroxide as initiator. Four of six fuels oxidize faster at 100 C than in previous work at 130 C with initiator. Four any single substrate, the amount of gum produced for the oxygen absorbed is similar at 100 and 130 C even with large changes in rates and t-Bu2O2 concentrations. Thus, one mechanism of gum formation is intimately associated with oxidation. The effects of t-Bu2O2 concentration on the rates of oxygen absorption and gum formation show that gum formation is associated with chain termination by two peroxy radicals. In general, the pure hydrocarbons have long kinetic chains and give good yields of hydroperoxides. The fuels give short kinetic chains and produce little hydroperoxide but but much more gum formation is the coupling of substrates by peroxides in the absence of oxygen. The mechanism, condensation of oxidation products from alkylnaphthalenes, is also proposed.

Mayo, F.R.; Lan, B.Y.

1987-01-01

315

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

316

Guar gum as potential film coating material for colon-specific delivery of fluorouracil.  

PubMed

The potential of guar gum as a film coating material for colon-specific delivery of 5-fluorouracil is evaluated in this study. The guar gum-based multi-unit pellet system is prepared by coating guar gum and pH-sensitive polymer Eudragit FS30D sequentially around drug-loaded non-pareil cores in a fluid-bed coater. The outer Eudragit FS coating protects the system against gastrointestinal environment and dissolves rapidly in distal small intestine, where a lumen pH of over 7 triggers the dissolution of the enteric polymer. The inner guar gum coating works as a time-controlled retardant and offers additional protection of the pellets until it is degraded by microbial enzymes at the proximal colon. In vitro results indicate that guar gum is a feasible coating material to achieve timed and enzyme-triggered fluorouracil release. Pharmacokinetic study in beagle dogs shows delayed absorption of about 5 h and limited absorption fraction as a result of guar gum and Eudragit FS coating. PMID:18667456

Ji, C M; Xu, H N; Wu, W

2009-01-01

317

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

318

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

319

Efficacy of baking soda-containing chewing gum in removing natural tooth stain.  

PubMed

A 14-week, double-blind, randomized clinical trial was conducted with 126 healthy volunteers to compare the efficacy of twice-daily use of 3 baking soda-containing chewing gums in removing natural tooth stain when used in conjunction with a program of regular oral hygiene. All 3 chewing gums significantly reduced extrinsic stain (P < .0001) and improved the whitened appearance of teeth (P < .0001) at both the 2-week interim and the final 4-week evaluations. ARM & HAMMER DENTAL CARE The Baking Soda Gum (AHDC) reduced dental stain by 70.8%, compared to reductions of 71.9% and 65.3%, after use of 2 experimental gum formulations. Whitened appearance improved by 1.73 shade tabs using AHDC gum, and up to 2.49 shade tabs with the experimental formulations. These results suggest that the use of baking soda-containing gum after meals, in conjunction with good oral hygiene, can improve both extrinsic dental staining and the whitened appearance of teeth. PMID:11913307

Mankodi, S M; Conforti, N; Berkowitz, H

2001-07-01

320

Effects of a Baking Soda Gum on extrinsic dental stain: results of a longitudinal 4-week assessment.  

PubMed

An evaluation of the effects of ARM & HAMMER DENTAL CARE The Baking Soda Gum (AHDC) on extrinsic dental stain was made in 48 subjects presenting with measurable extrinsic stain. The subjects were randomized to use either the baking soda gum or a non-baking soda placebo gum for 20 minutes twice daily after lunch and dinner while brushing once daily. The procedure of limited brushing was chosen to simulate the level of hygiene normally practiced by participants entering a clinical study. After 4 weeks, the reduction in measurable extrinsic stain in the baking soda gum group was statistically significant (P = .0044) relative to baseline. Statistical analysis of the placebo gum group revealed no significant change in extrinsic stain from baseline. The magnitude of the unadjusted longitudinal reduction in extrinsic stain in the baking soda gum group was 29.7% at 4 weeks. PMID:11913306

Soparkar, P; Newman, M B

2001-07-01

321

Composition and physicochemical properties of locust bean gum extracted from whole seeds by acid or water dehulling pre-treatment  

Microsoft Academic Search

The purpose of this study was to extract locust bean gum (LBG) from whole seeds by two different dehulling pre-treatments. The first process consisted in separating the endosperm (gum) from the hull and the germ after seeds’ pre-treatment with boiling water. The second one used acidic pre-treatment. Then the composition and the physicochemical characteristics of the isolated gum were studied

Patrick Aubin Dakia; Christophe Blecker; Christelle Robert; Bernard Wathelet; Michel Paquot

2008-01-01

322

Steady shear flow properties of wild sage ( Salvia macrosiphon) seed gum as a function of concentration and temperature  

Microsoft Academic Search

The steady shear flow properties of dispersions of a new potential hydrocolloid, sage seed gum (SSG), were determined as a function of concentration (0.5–2% w\\/w), and temperature (20–50°C). SSG dispersions exhibited strong shear-thinning behavior at all conditions tested, which was even more pronounced than commercial hydrocolloids like xanthan, guar gum and locust bean gum. Different time-independent rheological models were used

Seyed M. A. Razavi; Hesam Taheri; Lida A. Quinchia

2011-01-01

323

A Study of the Cometary Globules in the GUM Nebula  

NASA Astrophysics Data System (ADS)

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

Sridharan, T. K.

1994-09-01

324

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

325

Jumping mechanisms in gum treehopper insects (Hemiptera, Eurymelinae).  

PubMed

Jumping in a species of Australian gum treehopper was analysed from high-speed images. Pauroeurymela amplicincta adults and nymphs lived together in groups that were tended by ants, but only adults jumped. The winged adults with a body mass of 23 mg and a body length of 7 mm had some morphological characteristics intermediate between those of their close relatives the leafhoppers (Cicadellidae) and the treehoppers (Membracidae). They, like leafhoppers, lacked the prominent prothoracic helmets of membracid treehoppers, and their large hind coxae were linked by press studs (poppers), that are present in leafhoppers but not treehoppers. The hindlegs were only 30-40% longer than the other legs and 67% of body length. They are thus of similar proportion to the hindlegs of treehoppers but much shorter than those of most leafhoppers. Jumping was propelled by the hindlegs, which moved in the same plane as each other beneath and almost parallel to the longitudinal axis of the body. A jump was preceded by full levation of the coxo-trochanteral joints of the hindlegs. In its best jumps, the rapid depression of these joints then accelerated the insect in 1.4 ms to a take-off velocity of 3.8 m s(-1) so that it experienced a force of almost 280 g. In 22% of jumps, the wings opened before take-off but did not flap until the gum treehopper was airborne, when the body rotated little in any plane. The energy expended was 170 ?J, the power output was 122 mW and the force exerted was 64 mN. Such jumps are predicted to propel the insect forwards 1450 mm (200 times body length) and to a height of 430 mm if there is no effect of wind resistance. The power output per mass of jumping muscle far exceeded the maximum active contractile limit of muscle and indicates that a catapult-like action must be used. This eurymelid therefore out-performs both leafhoppers and treehoppers in i ts faster acceleration and in its higher take-off velocity. PMID:23619401

Burrows, Malcolm

2013-07-15

326

Sustained-release from layered matrix system comprising chitosan and xanthan gum.  

PubMed

Sustained-release tablets of propranolol HCl were prepared by direct compression using chitosan and xanthan gum as matrix materials. The effective prolongation of drug release in acidic environment was achieved for matrix containing chitosan together with xanthan gum which prolonged the drug release more extensive than that containing single polymer. Increasing lactose into matrix could adjust the drug release characteristic by enhancing the drug released. Component containing chitosan and xanthan gum at ratio 1:1 and lactose 75% w/w was selected for preparing the layered matrix by tabletting. Increasing the amount of matrix in barrier or in middle layer resulted in prolongation of drug release. From the investigation of drug release from one planar surface, the lag time for drug release through barrier layer was apparently longer as the amount of barrier was enhanced. Least square fitting the experimental dissolution data to the mathematical expressions (power law, first order, Higuchi's and zero order) was performed to study the drug release mechanism. Layering with polymeric matrix could prolong the drug release and could shift the release pattern approach to zero order. The drug release from chitosan-xanthan gum three-layer tablet was pH dependent due to the difference in charge density in different environmental pH. FT-IR and DSC studies exhibited the charge interaction between of NH3+ of chitosan molecule and COO- of acetate or pyruvate groups of xanthan gum molecule. The SEM images revealed the formation of the loose membranous but porous film that was due to the gel layer formed by the polymer relaxation upon absorption of dissolution medium. The decreased rate of polymer dissolution resulting from the decreased rate of solvent penetration was accompanied by a decrease in drug diffusion due to ionic interaction between chitosan and xanthan gum. This was suggested that the utilization of chitosan and xanthan gum could give rise to layered matrix tablet exhibiting sustained drug release. PMID:17613024

Phaechamud, Thawatchai; Ritthidej, Garnpimol C

2007-06-01

327

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

328

Smoking Cessation during Alcohol Treatment: A Randomized Trial of Combination Nicotine Patch plus Nicotine Gum  

PubMed Central

Aims The primary aim was to compare the efficacy of smoking cessation treatment using the combination of active nicotine patch plus active nicotine gum versus therapy consisting of active nicotine patch plus placebo gum in a sample of alcohol dependent tobacco smokers in an early phase of outpatient alcohol treatment. A secondary aim was to determine whether or not there were any carryover effects of combination nicotine replacement on drinking outcomes. Design Small scale randomized double-blind placebo controlled clinical trial with one-year smoking and drinking outcome assessment. Setting Two outpatient substance abuse clinics provided a treatment platform of behavioral alcohol and smoking treatment delivered in three months of weekly sessions followed by three monthly booster sessions. Participants Participants were 96 men and women with a diagnosis of alcohol abuse or dependence and smoking 15 or more cigarettes per day. Intervention All participants received open-label transdermal nicotine patch and were randomized to receive either 2 mg nicotine gum or placebo gum under double blind conditions. Findings Analysis of 1-year follow-up data revealed that patients receiving nicotine patch plus active gum had better smoking outcomes than those receiving patch plus placebo gum on measures of time to smoking relapse and prolonged abstinence at 12 months. Alcohol outcomes were not significantly different across medication conditions. Conclusions Results of this study were consistent with results of larger trials of smokers without alcohol problems showing that combination therapy (nicotine patch plus gum) is more effective than monotherapy (nicotine patch) for smoking cessation. PMID:19549054

Cooney, Ned L.; Cooney, Judith L.; Perry, Bridget L.; Carbone, Michael; Cohen, Emily H.; Steinberg, Howard R.; Pilkey, David T.; Sevarino, Kevin; Oncken, Cheryl A.; Litt, Mark D.

2009-01-01

329

The environs of the HII region Gum31  

E-print Network

We analyze the distribution of the interstellar matter in the environs of the \\hii region Gum 31, excited by the open cluster NGC 3324, located in the complex Carina region, with the aim of investigating the action of the massive stars on the surrounding neutral material. We use 21cm-line data, radio continuum images at 0.843, 2.4 and 4.9 GHz, $^{12}${\\bf CO(1-0)} observations, and IRAS and MSX infrared data. Adopting a distance of 3 kpc for the \\hii\\ region and the ionizing cluster, we have derived an electron density of 33$\\pm$3 cm$^{-3}$ and an ionized mass of (3.3$\\pm$1.1)$\\times10^3$ M$_{\\odot}$ based on the radio continuum data at 4.9 GHz. The \\hi 21-cm line images revealed an \\hi shell surrounding the H {\\sc ii} region. The \\hi structure is 10.0$\\pm$1.7 pc in radius, has a neutral mass of 1500$\\pm$500 M$_{\\odot}$, and is expanding at 11 km s$^{-1}$. The associated molecular gas amounts to (1.5$\\pm$0.5)$\\times10^5$ M$_{\\odot}$, being its volume density of about 500 cm^{-3}. This molecular material proba...

Cappa, C; Amorin, R; Vasquez, J

2007-01-01

330

Synthesis of carboxylated locust bean gum hydrogels by ionizing radiation  

NASA Astrophysics Data System (ADS)

In the present study, a locust bean gum (LBG) was carboxylated by a technique known as TEMPO mediated oxidation. Characterization of the carboxylated LBG (CLBG) was performed by spectroscopic and chromatographic techniques. The CLBG was then irradiated with gamma rays utilizing a 60Co gamma-ray source at the dose rates of 30 Gy/h and 300 Gy/h up to 10 kGy in very concentrated solutions called as "paste-like" and in the presence of acetylene. Sol-gel analysis was carried out in order to determine the polymer-to-gel conversion ratios. It was found that the swelling capacity of the hydrogels prepared in the presence of acetylene increased with dose from 19,000% to 34,000%. The gelation percentage was observed to increase rapidly up to 5.0 kGy, which then continued to increase at a slower rate. Despite low gelation, the crosslink density of the CLBG hydrogels prepared in the paste-like state was observed to be high.

Hayrabolulu, Hande; ?en, Murat; Çelik, Gökçe; Kavakl?, P?nar Akka?

2014-01-01

331

Stability of acidic egg white protein emulsions containing xanthan gum.  

PubMed

The influence of xanthan gum concentration on the physicochemical stability of model oil-in-water emulsions prepared with egg white protein at pH 3.8 and containing 150 mM NaCl was investigated by following droplet aggregate formation, rheological changes, and serum separation with storage time. Egg white emulsions were more strongly flocculated and exhibited higher stability against creaming than those of yolk, irrespective of the presence or absence of xanthan. Depletion effects, originating from the presence in the continuous phase of the emulsions of nonadsorbing xanthan molecules, intensified droplet-droplet flocculation effects and resulted in large droplet flocs. At relatively low xanthan contents, the emulsions exhibited higher stability against creaming compared to the respective control emulsions probably due to the formation of a continuous droplet aggregate network structure. At higher xanthan contents, less extensive droplet interactions, due to slowly evolving microstructure of phase-separated xanthan-rich and xanthan-depleted regions, resulted in emulsions exhibiting increased stability against creaming. The role of interactions between protein molecules adsorbed on neighboring droplets in these changes and their effect on emulsion aging are discussed. PMID:17177555

Drakos, Antonios; Kiosseoglou, Vassilis

2006-12-27

332

Antiglycating potential of gum arabic capped-silver nanoparticles.  

PubMed

Advanced glycation end products are major contributors to the pathology of diabetes, Alzheimer's disease, and atherosclerosis; accordingly, identification of antiglycation compounds is attracting considerable interest. In the present study, the inhibitory effect of gum arabic capped-silver nanoparticles on advanced glycation end products formation was monitored by several biophysical techniques. Silver nanoparticles were characterized by ultraviolet-visible, high-resolution transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Bovine serum albumin and methylglyoxal mixtures incubated with increasing concentrations of silver nanoparticles showed significant reductions in advanced glycation end product formation that were confirmed by ultraviolet-visible, fluorescence spectrometry, and high-performance liquid chromatography techniques. High-performance liquid chromatography showed decreased adduct formation of glycated protein in the presence of silver nanoparticles. The structural changes induced by silver nanoparticles were further confirmed by circular dichroism and Fourier transform infrared spectroscopy. Strong inhibition of advanced glycation end product formation was observed in the presence of elevated silver nanoparticles. The results of this study suggest that silver nanoparticles are a potent antiglycating agent. PMID:25080376

Ashraf, Jalaluddin M; Ansari, Mohammad Azam; Choi, Inho; Khan, Haris M; Alzohairy, Mohammad A

2014-09-01

333

An evaluation of sodium bicarbonate chewing gum as a supplement to toothbrushing for removal of dental plaque from children's teeth.  

PubMed

The purpose of this human clinical study was to determine whether a commercial chewing gum containing 5% sodium bicarbonate (ARM & HAMMER DENTAL CARE The Baking Soda Gum [AHDC]) was effective in removing dental plaque when used as a supplement to regular toothbrushing by children. Healthy children (N = 28, average age = 11 years) were randomly distributed into 2 groups. One group was instructed to chew 2 tablets of AHDC chewing gum for 20 minutes 2 times each day (after lunch and dinner) in addition to their normal toothbrushing regimen. The other group used a sugarless mint tablet twice daily during the same period in addition to toothbrushing. After 1 week of using their assigned product, all participants were again examined for oral health and plaque. After a 1-week washout period, subjects were crossed over to the opposite group. Among the 21 participants completing the study, the AHDC chewing gum significantly (P < .0001) reduced plaque by 15% after 1 week compared to the mint tablet control, as measured by the Modified Quigley-Hein Plaque Index. When longitudinally compared to the baseline plaque scores, the gum resulted in a significant (P < .01) 10% reduction of plaque on the teeth. Subanalysis of the data showed that the AHDC chewing gum was particularly effective on the lingual surfaces and the posterior teeth and least effective on the facial surfaces of the anterior teeth, which do not readily come into direct contact with the gum during mastication. The bicarbonate gum demonstrated significant plaque reduction in all other areas of the mouth, even on tooth surfaces not directly contacted during chewing. Compliance with the chewing gum regimen was excellent, and oral health exams did not indicate any adverse events among children using either the chewing gum or mint tablets. In this study, regular use of AHDC chewing gum was safe and effective in removing dental plaque and served as a significant complement to the daily toothbrushing regimen of children. PMID:11913309

Kleber, C J; Davidson, K R; Rhoades, M L

2001-07-01

334

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

PubMed Central

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

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

2007-01-01

335

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

336

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

PubMed

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

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

2014-11-01

337

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

NASA Astrophysics Data System (ADS)

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

Elster, Clemens

2014-08-01

338

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

339

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

340

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

341

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

342

Influence of locust bean gum\\/?-carrageenan mixtures on whipping and mechanical properties and stability of dairy creams  

Microsoft Academic Search

The influence of locust bean gum (LBG)–?-carrageenan mixtures on whipping properties and rheological properties of whipped dairy cream was analysed as a function of the gum concentration. Whipping properties (time and overrun) and mechanical properties (creep compliance and extrusion tests) were studied on whipped cream immediately after whipping and after 24h refrigeration (5°C). The stabiliser mixtures in the studied concentration

M. M Camacho; N Mart??nez-Navarrete; A Chiralt

1998-01-01

343

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 and people with gastric ulcers or a history of heart disease. Treatment (acupuncture, nicotine gum

Paris-Sud XI, Université de

344

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

345

Theory of the nonplanar splitting of screw dislocations in Gum Metal S. V. Bobylev,1 T. Ishizaki,2 S. Kuramoto,2 and I. A. Ovid'ko1  

E-print Network

Theory of the nonplanar splitting of screw dislocations in Gum Metal S. V. Bobylev,1 T. Ishizaki,2 nonplanar splitting of perfect dislocations into partials in a newly discovered group of alloys called Gum experimental data on suppression of dislocation slip in Gum Metal reported in the literature. DOI: 10.1103/Phys

Ovid'ko Ilya A.

346

Text for MLR Year 2002 GUM Survey Basic Issue B.doc 22/07/08 1 SPECIES RICHNESS AND ABUNDANCE OF BIRDS IN  

E-print Network

Text for MLR Year 2002 GUM Survey Basic Issue B.doc 22/07/08 1 SPECIES RICHNESS AND ABUNDANCE OF BIRDS IN MT LOFTY RANGES GUM WOODLAND HABITAT: YEAR 2002 SURVEY Basic Issue B 29-03-2008 M. L patches of gum woodland in the spring and summer of 2002-2003. Each patch contained one or more 2-ha sites

Queensland, University of

347

Discovery of X-ray emission associated with the Gum Nebula  

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

348

Oxidation and gum formation in diesel fuels. Interim technical report, May-December 1985  

SciTech Connect

This Report describes experiments on oxidation and gum formation from n-dodecane, tetralin, and several diesel fuels at 43, 60, and 100 C, with and without added initiators, t-butyl peroxide and 2,2'azobis(2-methylpropionitrile) (ABN). Experiments on gum determination and a manuscript for publication, Gum and Deposit Formation from Jet Turbine and Diesel Fuels at 100 C, are included. One objective of work on this Contract is to relate oxidations of diesel fuels at 100 and 130 C, where experiments can be performed in hours or days, to standard tests for fuel stability at ambient temperatures and 43.3 C (110 F), which require many weeks. A second objective is to devise a fast test for fuel stability.

Mayo, F.R.

1985-12-20

349

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

SciTech Connect

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

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

1982-08-01

350

Effect of dry heating with ionic gums on physicochemical properties of starch.  

PubMed

Corn starch, potato starch, pea starch were impregnated with ionic gums (sodium alginate, CMC, and xanthan, 1% based on starch solids) and heat-treated in a dry state for 0, 2, or 4 h at 130°C. Effects of the dry heating on paste viscosity (RVA), microstructure and thermal properties were examined. Dry heat treatment with ionic gums reduced the pasting temperature of the three starches. Heating with xanthan increased the paste viscosity of corn and potato starch. With heat treatment, the paste viscosity of all the starch-sodium alginate mixtures decreased. Heating with CMC increased the paste viscosity of potato starch, but decreased that of corn and pea starch. After dry-heating, To, Tp and Tc of potato starch with ionic gums decreased significantly. SEM of potato starch with CMC showed that the gel structure got compacter after drying-heating. Heat treatment obviously improved the functional properties of the three starches. PMID:23194543

Sun, Qingjie; Si, Fumei; Xiong, Liu; Chu, Lijun

2013-02-15

351

Development and characterization of guar gum nanoparticles for oral immunization against tuberculosis.  

PubMed

Abstract The main aim of this study was to develop an effective carrier system containing Ag85A-loaded guar gum nanoparticles for oral vaccination against tuberculosis. Nanoparticles were prepared by Nanoprecipitation method. The developed particles with mean diameter 895.5?±?14.73?nm and high antigen entrapment seem to be optimum for oral vaccine delivery. The acid protection assay, Peyer's patch uptake study and in-vitro antigen study confirmed that the developed formulations can protect the antigen from harsh gastric environment and can safely deliver the antigen to the intestinal region. In vivo studies data indicated that the developed nanocarriers can induce a strong mucosal as well as systemic immune response. Therefore, the experimental evidence suggests that guar-gum nanoparticle findings indicated that the guar gum nanoparticles can be utilized for safe and effective vaccine delivery via oral route. PMID:24611942

Kaur, Mandeep; Malik, Basant; Garg, Tarun; Rath, Goutam; Goyal, Amit K

2014-03-10

352

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

353

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.

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

2014-01-01

354

Standard test method for existent gum in fuels by jet evaporation  

SciTech Connect

This method covers determination of the existent gum in motor gasoline and aircraft fuels at the time of test. Provisions are made for the determination of the unwashed gum content of motor gasoline. Summary of method: a measured quantity of fuel is evaporated under controlled conditions of temperature and flow of air or steam. For aviation gasoline and aircraft turbine fuel, the resulting residue is weighed and reported as milligrams per 100 mL. For motor gasoline, the residue is weighed before and after extracting with n-heptane and the results reported as milligrams per 100 mL.

Not Available

1980-01-01

355

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

356

Caffeinated chewing gum increases repeated sprint performance and augments increases in testosterone in competitive cyclists  

Microsoft Academic Search

This investigation reports the effects of caffeinated chewing gum on fatigue and hormone response during repeated sprint performance\\u000a with competitive cyclists. Nine male cyclists (mean ± SD, age 24 ± 7 years, VO2max 62.5 ± 5.4 mL kg?1 min?1) completed four high-intensity experimental sessions, consisting of four sets of 30 s sprints (5 sprints each set). Caffeine\\u000a (240 mg) or placebo was administered via chewing gum following the second set of each

Carl D. PatonTimothy; Timothy Lowe; Athena Irvine

2010-01-01

357

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

358

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

Microsoft Academic Search

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

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

1997-01-01

359

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

360

The environs of the HII region Gum31  

E-print Network

We analyze the distribution of the interstellar matter in the environs of the \\hii region Gum 31, excited by the open cluster NGC 3324, located in the complex Carina region, with the aim of investigating the action of the massive stars on the surrounding neutral material. We use 21cm-line data, radio continuum images at 0.843, 2.4 and 4.9 GHz, $^{12}${\\bf CO(1-0)} observations, and IRAS and MSX infrared data. Adopting a distance of 3 kpc for the \\hii\\ region and the ionizing cluster, we have derived an electron density of 33$\\pm$3 cm$^{-3}$ and an ionized mass of (3.3$\\pm$1.1)$\\times10^3$ M$_{\\odot}$ based on the radio continuum data at 4.9 GHz. The \\hi 21-cm line images revealed an \\hi shell surrounding the H {\\sc ii} region. The \\hi structure is 10.0$\\pm$1.7 pc in radius, has a neutral mass of 1500$\\pm$500 M$_{\\odot}$, and is expanding at 11 km s$^{-1}$. The associated molecular gas amounts to (1.5$\\pm$0.5)$\\times10^5$ M$_{\\odot}$, being its volume density of about 500 cm^{-3}. This molecular material probably represents the remains of the cloud where the young open cluster NGC 3324 was born. The distributions of the ionized and molecular material, along with that of the emission in the MSX band A suggest that a photodissociation region has developed at the interface between the ionized and molecular gas. We conclude that either the massive stars in the open cluster have weak stellar winds or the stellar winds have blown during a very short period of time to create an interstellar bubble in an interstellar medium as dense as observed. IRAS, MSX, and 2MASS point sources projected onto the molecular envelope are compatible with protostellar candidates, showing the presence star forming regions. The expansion of the \\hii region has triggered stellar formation in the molecular shell.

C. Cappa; V. S. Niemela; R. Amorin; J. Vasquez; ;

2007-07-13

361

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

362

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

363

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

364

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

365

Effect of nicotine chewing gum as an adjunct to general practitioner's advice against smoking  

Microsoft Academic Search

This study was designed to see whether the offer and prescription of nicotine chewing gum would enhance the efficacy of general practitioners' advice to stop smoking. A sample of 1938 cigarette smokers who attended the surgeries of 34 general practitioners in six group practices were assigned by week of attendance (in a balanced design) to one of three groups: (a)

M A Russell; R Merriman; J Stapleton; W Taylor

1983-01-01

366

Reduction of the viscosity of solutions viscosified with xanthan gum polymers  

SciTech Connect

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

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

1991-10-08

367

The effect of depolymerised guar gum on the stability of skim milk  

Microsoft Academic Search

We studied the interactions between casein micelles and (depolymerised) guar gum, degraded by heating its aqueous solutions at low pH. The guar samples were characterised by a combination of size-exclusion chromatography and light scattering, which yielded the distribution of molar mass and corresponding radius of gyration. The relation between molar mass and radius of gyration showed that guar can be

R. Tuinier; E. ten Grotenhuis; C. G. de Kruif

2000-01-01

368

Assessment of Albizia zygia gum as a binding agent in tablet formulations  

Microsoft Academic Search

Albizia gum has been evaluated as a binding agent in ta- blet formulations in comparison with gelatin BP. Com- pressional properties were analyzed using density mea- surements and the compression equations of Heckel and Kawakita as assessment parameters, while the mechanical properties of the tablets were assessed using the crushing strength and friability of the tablets. Drug release proper- ties

OLUWATOYIN A. ODEKU

2005-01-01

369

Interchain association of locust bean gum in sucrose solutions: An interpretation based on thixotropic behavior  

Microsoft Academic Search

The thixotropic behavior of locust bean gum (LBG) in sucrose solutions after freezing and thawing was investigated using a transient rheological approach. The thixotropy is attributed to the forced association of LBG chains during freezing. The effects of shear rate, shearing temperature, sucrose concentration, and number of freeze–thaw cycles on the transient viscosity profile were studied. A second-order kinetic equation

Ching-Feng Mao; Jia-Chin Chen

2006-01-01

370

Water Sorption and Water Vapour Permeability Properties of Polysaccharide (Locust Bean Gum) Based Edible Films  

Microsoft Academic Search

Water sorption data of edible films containing locust bean gum (LBG) and polyethylene glycol (PEG) 200 as plasticizer determined at different water activities showed that equilibrium water content increases sharply aboveaw =0.65. The effects of the amount and molecular weight of PEG on water vapour transfer properties of these edible films were also examined. Generally, permeance and permeability values of

Meltem Aydinli; Mehmet Tutas

2000-01-01

371

Effect of deacetylation on the synergistic interaction of acetan with locust bean gum or konjac mannan  

Microsoft Academic Search

It has been discovered that deacetylation of the bacterial polysaccharide acetan promotes synergistic interactions with either locust bean gum (LBG) or konjac mannan (KM). Acetan is similar in structure to xanthan, and adopts a similar 5-fold conformation in the solid state. Like xanthan, it shows a thermally reversible order (helix)-disorder (coil) transition in solution. Both polymers have a cellulosic backbone

Cordelia Ojinnaka; Geoffrey J. Brownsey; Edwin R. Morris; Victor J. Morris

1997-01-01

372

Phase equilibria and mechanical properties of gel-like water–gelatin–locust bean gum systems  

Microsoft Academic Search

The establishment of phase equilibrium in aqueous gelatin–locust bean gum (LBG) systems in the process of cooling from 313 to 291 K in specific conditions, passes ahead of the gelation process. This allows the suggestion that macrostructure and mechanical properties of the system can be predicted on the basis of knowledge of its phase diagram, obtained for the liquid gelatin–LBG

M. M Alves; Yu. A Antonov; M. P Gonçalves

2000-01-01

373

NMR water mobility in xanthan and locust bean gum mixtures: possible explanation of microbial response  

Microsoft Academic Search

Molecular and structural mobility of xanthan and locust bean gum mixtures (with and without mannitol) were studied in relation to microbial stability. Molecular mobility was measured by solid state 1H and 2H NMR and by 2H high resolution NMR while differential scanning calorimetry and dynamic mechanical analysis were used to investigate structural mobility. The NMR mobile signal was found to

E. Vittadini; L. C. Dickinson; P. Chinachoti

2002-01-01

374

Thermodynamic incompatibility and microstructure of milk protein\\/locust bean gum\\/sucrose systems  

Microsoft Academic Search

Phase equilibria of milk protein\\/locust bean gum systems in high levels of sucrose were investigated to understand the behaviour of these components in diary products and also to look at the particular effect of sucrose. Two milk protein systems were investigated, skimmed milk (SMP) and native phosphocaseinate (PCN). The main advantage of using this latter sample is that it is

C. Schorsch; M. G. Jones; I. T. Norton

1999-01-01

375

Modified Alternan: A Novel Microbial Gum with Potential as a Low-Viscosity Bulking Agent  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alternan is a microbial gum produced by rare strains of the GRAS lactic acid bacterium, Leuconostoc mesenteroides. The unique alternating alpha-(1,6) and alpha-(1,3) linkage pattern of this glucan imparts high solubility and resistance to most digestive enzymes. Previously, we invented a bioconver...

376

Konjac glucomannan\\/xanthan gum enzyme sensitive binary mixtures for colonic drug delivery  

Microsoft Academic Search

The polysaccharide konjac glucomannan (KGM) is degraded in the colon but not the small intestine, which makes it potentially useful as an excipient for colonic drug delivery. With xanthan gum (XG) KGM forms thermoreversible gels with hitherto unexplored biodegradation properties. In this work, rheological measurements of KGM and KGM\\/XG systems incubated with and without Aspergillus niger ?-mannanase (used to mimic

Felipe Alvarez-Manceñido; Mariana Landin; Ramón Martínez-Pacheco

2008-01-01

377

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

378

Locust bean gum (LBG) as a gelling agent for plant tissue culture media  

Microsoft Academic Search

Locust bean gum (LBG) is a natural hydrocolloid extracted from the seeds of carob tree (Ceratonia siliqua L.). This work describes the successful use of LBG as a gelling agent in combination with agar for shoot multiplication and rooting of carob tree and Iberian rose shoots. Its presence did not affect the multiplication rate of both species. The rooting frequency

S. Gonçalves; A. Romano

2005-01-01

379

An Evaluation of the Reproductive and Developmental Effects of Tara Gum in Rats  

Microsoft Academic Search

In a multigeneration reproduction study, tara gum or ?-cellulose was administered to male and female Charles River CD rats as a dietary admixture at levels of 5% (50,000 ppm) through 3 successive generations. All matings consisted of 10 males and 20 females per group. All litters were maintained until they were at least 21 days old (end of lactation). Fertility

Joseph F. Borzelleca; John L. Egle

1993-01-01

380

The Effect of Mg 2+ and Tara Gum Concentrations on the Rheological Properties of WPI Solutions  

Microsoft Academic Search

Cold-set gels of whey protein isolate (WPI) and of WPI plus polysaccharide were produced. The cold gelation was induced through the addition of magnesium chloride whose cation is an alternative to the most common cations used in this kind of gelation. The polysaccharide used was tara gum (TG) which is a galactomannan with many applications in the food industry. The

M. Vázquez da Silva; J. M. P. Q. Delgado

2009-01-01

381

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

382

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...

383

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 ...

384

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...

385

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...

386

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

387

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 ...

388

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

389

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

390

"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

391

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

Microsoft Academic Search

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

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

2007-01-01

392

Properties of Delonix regia seed gum as a novel tablet binder.  

PubMed

The mechanical and disintegration properties of paracetamol tablets formulated using Delonix regia seed gum (DRSG) as a binder have been studied in this work. Acacia BP (ACG) and tragacanth BP (TRG) were used as official gum standards. The mechanical properties, i.e. tensile strength (TS) and brittle fracture index (BFI), showed that with an increase in concentration of the gum binder, the tensile strength increased while the BFI was reduced. The crushing strength - friability/disintegration time ratio used to analyze the disintegration properties gave a rank order: tablets containing DRSG > tablets containing ACG > tablets containing TRG at 1%, w/w binder concentration while for higher binder concentrations, the rank order is: tablets containing ACG > tablets containing TRG > tablets containing DRSG. The results suggest that while Delonix regia seed gum may be useful as a binder, its use at a low concentration will improve the balance between the binding and disintegration properties of tablets when a faster disintegration is desired, while its use at a high concentration could serve the desire for a modified or sustained release tablet formulation. PMID:19702177

Adetogun, Gbadegesin E; Alebiowu, Gbenga

2009-01-01

393

Oil-entrapped sterculia gum-alginate buoyant systems of aceclofenac: development and in vitro evaluation.  

PubMed

The current investigation deals with the development and optimization of oil-entrapped sterculia gum-alginate buoyant beads containing aceclofenac by ionotropic emulsion-gelation technique using 3(2) factorial design. The effect of polymer to drug ratio and sodium alginate to sterculia gum ratio on the drug entrapment efficiency (%), and cumulative drug release after 7 h (%) was optimized. The optimized oil-entrapped sterculia gum-alginate buoyant beads containing aceclofenac (F-O) showed drug entrapment efficiency of 90.92±2.34%, cumulative drug release of 41.65±3.97% after 7 h in simulated gastric fluid (pH 1.2), and well buoyancy over 8 h in simulated gastric fluid (pH 1.2) with 5.20 min buoyant lag-time. The in vitro drug release from these buoyant beads followed Korsmeyer-Peppas model (R(2)=0.9866-0.9995) with anomalous (non-Fickian) diffusion drug release mechanism. These new sterculia gum-alginate buoyant beads containing aceclofenac were also characterized using SEM, FTIR, and P-XRD analysis. PMID:23334180

Guru, Pravat Ranjan; Nayak, Amit Kumar; Sahu, Rajendra Kumar

2013-04-01

394

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

395

Mechanisms of deformation in gum metal TNTZ-O and TNTZ titanium alloys: A comparative study on the oxygen influence  

E-print Network

Mechanisms of deformation in gum metal TNTZ-O and TNTZ titanium alloys: A comparative study) and gum metal Ti­23Nb­0.7Ta­2Zr­1.2O (TNTZ-O) alloys were synthesized by cold crucible levitation melting-type Ti-based alloys, the multifunctional Ti­23Nb­0.7Ta­2Zr­1.2O alloy composition (mol.%), called "gum

Boyer, Edmond

396

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

SciTech Connect

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

Pinches, A.; Pallent, L.J.

1986-10-01

397

Application of Uncertainty in Measurement (GUM) to Isotope Mass Spectrometry: Introduction, Implemention, and Examples  

NASA Astrophysics Data System (ADS)

As the measured value and its unit are integral parts of a measurement, so is a statement of the associated measurement uncertainty. The importance of providing an uncertainty that can reasonably be attributed to the measured value is often underrated. An assessment of uncertainty provides confidence in the value of the measurement, judgement on significance of differences between measurement results, information regarding the capability of the measurement procedure, and quality assurance. The limitations of the classical error analysis were seen as a hindrance to communication of scientific and technical measurement results, initiating the development of the Guide to the Expression of Uncertainty in Measurement (GUM) in the late 1970s. Just as the use of the International System of Units brings coherence to measurements, the International Organization for Standardization Guide to the Expression of Uncertainty in Measurement recommends a standardized way of expressing uncertainty in all kinds of measurements. Consequently, GUM has been adopted by most of the national metrology institutes in the world. A short introduction to GUM and the logical steps leading to its development will be presented, as well as a comparison between classical error analysis and GUM. Examples related to mass spectrometry for isotopic and elemental analysis will be discussed. The merits of GUM - transparency of the uncertainty evaluation, the treatment of uncertainties in a consistent logical way, and the presentation of an uncertainty budget resulting in a feedback to the analyst (i.e. identifies the dominant components of uncertainty and allows better understanding and improvement of the measurement process) - will be emphasised.

Buerger, S.; Essex, R. M.; Mathew, K. J.; Thomas, R. B.

2008-12-01

398

Synthesis, characterization and evaluation of the antioxidant potential of vanadium encapsulated guar gum nanoparticles.  

PubMed

The present study investigated the antioxidant potential of guar gum macroparticles (GGMs), vanadium oxide sulphate (VS) encapsulated guar gum macroparticles (GVMs), guar gum nanoparticles (GGNs), VS encapsulated guar gum nanoparticles (GVNs) and VS. GGNs and GVNs prepared by nanoprecipitation were characterized by SEM (scanning electron microscopy), TEM (transmission electron microscopy) and particle size analysis to confirm the nanostructure of the particles. Particle size analysis revealed that GVNs possess a size of 239 nm, about 148 nm larger than that of GGNs. TEM imaging and EDAX data also confirmed the formation of fine spherical nanoparticles with vanadium incorporation. In addition the larger size of GVNs also confirmed the vanadium incorporation. MTT assay showed that concentrations up to 100 nM of GVNs for 24 h exposure did not induce significant toxicity when VS was toxic (16%) at 100 nM. Various in vitro antioxidant assays (total reducing power, total antioxidant capacity, DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), hydroxyl radical and superoxide anion radical scavenging assays) revealed significantly high antioxidant potential of GVNs compared to GGNs, VS, GGMs and GVMs. The IC50 of GVNs was 23.21 ± 2.1 ?g mL(-1), 33.0 ± 2.93 ?g mL(-1), 21 ± 1.98 ?g mL(-1) and 22.79 ± 2.12 ?g mL(-1) for DPPH, ABTS, hydroxyl, superoxide anion scavenging activity assays respectively. The cell line based assay also proved that the GVN was more effective in reactive oxygen species (ROS) scavenging than VS against tertiary butyl hydrogen peroxide (TBHP) induced oxidative stress in H9c2 cell lines. The overall results indicated that vanadium in combination with nano guar gum exhibits significantly high antioxidant potential. PMID:24463743

Soumya, R S; Reshmi, R; Jomon, S; Antu, K A; Riya, M P; Raghu, K G

2014-03-01

399

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

400

Natural Giesekus fluids: shear and extensional behaviour of food gum solutions in the semi-dilute regime  

E-print Network

of the Trouton ratio. Higher concentration guar solutions, in the entangled regime, yielded different Giesekus fluid parameters for extension to those for simple shear. The extensional data for all concentrations of both gums collapsed to a common functional form...

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

2014-09-16

401

Influence of chemical extraction conditions on the physicochemical and functional properties of polysaccharide gum from durian (Durio zibethinus) seed.  

PubMed

Durian seed is an agricultural biomass waste of durian fruit. It can be a natural plant source of non-starch polysaccharide gum with potential functional properties. The main goal of the present study was to investigate the effect of chemical extraction variables (i.e., the decolouring time, soaking temperature and soaking time) on the physicochemical properties of durian seed gum. The physicochemical and functional properties of chemically-extracted durian seed gum were assessed by determining the particle size and distribution, solubility and the water- and oil-holding capacity (WHC and OHC). The present work revealed that the soaking time should be considered as the most critical extraction variable affecting the physicochemical properties of crude durian seed gum. PMID:22643356

Mirhosseini, Hamed; Amid, Bahareh Tabatabaee

2012-01-01

402

Comparative evaluation of the binding properties of two species of Khaya gum polymer in a paracetamol tablet formulation.  

PubMed

A study was made of the comparative effects of polymers obtained from two species of khaya tree - Khaya senegalensis and Khaya grandifoliola - as binding agents in a paracetamol tablet formulation. The mechanical properties of the tablets were assessed using the tensile strength (T), brittle fracture index (BFI) and friability (F) of the tablets while the drug release properties of the tablets were assessed using disintegration and dissolution times. The tensile strength, disintegration and the dissolution times of tablets increased with the increase in binder concentration while F and BFI decreased. K. senegalensis gum produced tablets with stronger mechanical properties with less tendency to laminate, and longer disintegration and dissolution times than K. grandifoliola gum. The results suggest that the polymer gum from K. senegalensis will be more appropriate as a binding agent than the gum from K. grandifoliola when higher mechanical strength and slower release profiles of tablets are desired. PMID:18720239

Adenuga, Yedunni A; Odeku, Oluwatoyin A; Adegboye, Temidayo A; Itiola, Oludele A

2008-01-01

403

The Effect of Natural Tree Gum and Environmental Condition on the Degradation of a Typical Automotive Clear Coat  

Microsoft Academic Search

In this work the effects of natural gum and its simulated compound (Arabic gum) on an acrylic based clear coat applied on\\u000a different basecoats were studied. The experiments were conducted at various aging processes to simulate the real outdoor conditions\\u000a by the aid of different analytical techniques including optical microscopy, scanning electron microscopy, ATR-FTIR spectroscopy,\\u000a DMTA and micro hardness measurements,

B. Ramezanzadeh; M. Mohseni; H. Yari

2010-01-01

404

The analysis of crude and purified locust bean gum: A comparison of samples from different carob tree populations in Tunisia  

Microsoft Academic Search

The crude and purified locust bean gum (LBG) from seven areas of the north and centre of Tunisia (Bouarada, Bargou, Kessra, Haffouz, Borj Toumi, Ben Arous and INRGREF) were analyzed for moisture, ash, protein, acid-insoluble matter and mannose\\/galactose ratio. The purified samples exhibited higher mannose\\/galactose ratios and lower amounts of ash, protein and acid-insoluble matter than the crude gum. The

N. Bouzouita; A. Khaldi; S. Zgoulli; L. Chebil; R. Chekki; M. M. Chaabouni; P. Thonart

2007-01-01

405

A comparative study on the compositions of crude and refined locust bean gum: In relation to rheological properties  

Microsoft Academic Search

In this study the composition of higher quality refined locust bean gum (rLBG) was compared with lower quality crude locust bean gum (cLBG) samples to understand the differences in functionality. M\\/G ratio has a great bearing on the viscosity and gelling properties of the material. The values obtained for M\\/G ratio of cLBG and rLBG samples range from 3.1 to

M. Samil Kök

2007-01-01

406

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

Microsoft Academic Search

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

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

2004-01-01

407

Gum chewing inhibits the sensory processing and the propagation of stress-related information in a brain network.  

PubMed

Stress is prevalent in human life and threatens both physical and mental health; stress coping is thus of adaptive value for individual's survival and well-being. Although there has been extensive research on how the neural and physiological systems respond to stressful stimulation, relatively little is known about how the brain dynamically copes with stress evoked by this stimulation. Here we investigated how stress is relieved by a popular coping behavior, namely, gum chewing. In an fMRI study, we used loud noise as an acute stressor and asked participants to rate their feeling of stress in gum-chewing and no-chewing conditions. The participants generally felt more stressful when hearing noise, but less so when they were simultaneously chewing gum. The bilateral superior temporal sulcus (STS) and the left anterior insula (AI) were activated by noise, and their activations showed a positive correlation with the self-reported feeling of stress. Critically, gum chewing significantly reduced the noise-induced activation in these areas. Psychophysiological interaction (PPI) analysis showed that the functional connectivity between the left AI and the dorsal anterior cingulate cortex (dACC) was increased by noise to a lesser extent when the participants were chewing gum than when not chewing gum. Dynamic causality modeling (DCM) demonstrated that gum chewing inhibited the connectivity from the STS to the left AI. These findings demonstrate that gum chewing relieves stress by attenuating the sensory processing of external stressor and by inhibiting the propagation of stress-related information in the brain stress network. PMID:23573184

Yu, Hongbo; Chen, Xi; Liu, Jinting; Zhou, Xiaolin

2013-01-01

408

Guar gum in rainbow trout ( Oncorhynchus mykiss) feed: The influence of quality and dose on stabilisation of faecal solids  

Microsoft Academic Search

In a dose–response study to identify optimal binder inclusion parameters, a control diet and five diets incorporating binder (0.2, 0.3 and 0.4% of a mid-viscosity guar gum (MV) and 0.2%, and 0.3% of a high-viscosity guar gum (HV)) were fed to triplicate groups of rainbow trout at a ration of 1.2% BW d?1. Feed conversion, growth, and with one exception,

Alexander Brinker

2007-01-01

409

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

410

Gum and deposit formation from jet turbine and diesel fuels at 100/sup 0/C  

SciTech Connect

Rates of oxidation and gum formation for six hydrocarbons, three jet turbine fuels and three diesel fuels have been measured at 100/sup 0/C in the presence of t-Bu/sub 2/O/sub 2/ as initiator. Four of the six fuels oxidize faster at 100/sup 0/C than in previous work at 130/sup 0/C without initiator. For any single substrate, the amount of gum produced for the oxygen absorbed is similar at 100 and 130/sup 0/C, even with large changes in rates and t-Bu/sub 2/O/sub 2/ concentrations. In general, the pure hydrocarbons have long kinetic chains and give good yields of hydroperoxides.

Mayo, F.R.; Lan, B.Y.

1987-02-01

411

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

412

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

413

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

414

Long-term Use of Nicotine Chewing Gum and Mercury Exposure from Dental Amalgam Fillings  

Microsoft Academic Search

In experimental studies, chewing gum has been shown to increase the release rate of mercury vapor from dental amalgam fillings. The aim of the present study was to investigate the influence of long-term frequent chewing on mercury levels in plasma and urine. Mercury levels in plasma (P-Hg) and urine (U-Hg), and urinary cotinine were examined in 18 subjects who regularly

G. Sällsten; J. Thorén; L. BarregÅrd; A. Schütz; G. Skarping

1996-01-01

415

Leaf Respiration of Snow Gum in the Light and Dark. Interactions between Temperature and Irradiance  

Microsoft Academic Search

We investigated the effect of temperature and irradiance on leaf respiration (R, non-photorespiratory mitochondrial CO2 release) of snow gum (Eucalyptus pauciflora Sieb. ex Spreng). Seedlings were hydroponically grown under constant 20°C, controlled- environment conditions. Measurements of R (using the Laisk method) and photosynthesis (at 37 Pa CO2) were made at several irradiances (0-2,000 mmol photons m22 s21) and temperatures (6°C-30°C).

Owen K. Atkin; John R. Evans; Marilyn C. Ball; Hans Lambers; Thijs L. Pons

2000-01-01

416

Effects of nicotine gum on repeated administration of the stroop test  

Microsoft Academic Search

Using a double-blind procedure, 24 non-smoking subjects chewed either 2 mg nicorette® gum or a placebo for 20 min, before completing a Stroop test on three occasions. Colour-word reading and simple colour naming times were consistent across repeats, and were unaffected by nicotine. However, the time taken to name the colour of incongruous colour word stimuli declined across trials. This

Stephen C. Provost; Ros Woodward

1991-01-01

417

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

418

Matrix properties of a new plant gum in controlled drug delivery  

Microsoft Academic Search

A new plant gum, Okra (extracted from the pods ofHibiscus esculentus), has been evaluated as a controlled-release agent in modified release matrices, in comparison with sodium car-boxymethyl\\u000a cellulose (NaCMC) and hydroxypropylmethyl cellulose (HPMC), using Paracetamol as a model drug. Tablets were produced by direct\\u000a compression and thein-vitro drug release was assessed in conditions mimicking the gastro intestinal system, for 6

V. D. Kalu; M. A. Odeniyi; K. T. Jaiyeoba

2007-01-01

419

CONTROL OF PIERCE'S DISEASE THROUGH DEGRADATION OF XANTHAN GUM Project Leader  

Microsoft Academic Search

Acinetobacter johnsonii GX123, a Xylella gum-degrading endophyte was co-inoculated with Xylella fastidiosa strain Texas in oleander plants to determine its efficacy as a biocontrol agent in preliminary experiments. Symptoms appeared in both plants inoculated with X. fastidiosa alone and plants co-inoculated with the endophyte. However, symptoms were more severe and appeared earlier in plants inoculated with X. fastidiosa than in

Donald A. Cooksey; Neal L. Schiller; Rosina Bianco; Seung-Don Lee; Korsi Dumenyo

420

Microstructure and flow behaviour of liquid water-gelatin-locust bean gum systems  

Microsoft Academic Search

Liquid water-gelatin-locust bean gum (LBG) systems, in the conditions of lowest compatibility (near the isoelectric pH of the protein), were explored using confocal laser scanning microscopy and viscometry. Confocal microscopy observation proved to be a more sensitive method to assess the phase state of the systems than the usual centrifugation or viscometric ones. It showed that in fact the system

M. M. Alves; C. Garnier; J. Lefebvre; M. P. Gonçalves

2001-01-01

421

Interactions between locust bean gum and cellulose characterized by 13C n.m.r. spectroscopy  

Microsoft Academic Search

Molecular interactions between locust bean gum (LBG) and cellulose crystallite surfaces appear to involve most mannosyl residues of the mannan backbone, not just the small proportion contained in long segments which lack galactosyl residues. This conclusion is based on: (1) relative strengths of13C n.m.r. signals at 102.2 ppm in the cross-polarization (CP) spectrum and 101.3 ppm in the single-pulse excitation

Roger H. Newman; Jacqueline A. Hemmingson

1998-01-01

422

Binding of mineral elements to locust bean gum influences availability in vitro  

Microsoft Academic Search

Experiments were conducted to evaluate the extent to which element binding of locust bean gum (LBG) affects the availability\\u000a of calcium, iron, and zinc in the gut. Infant formula was supplemented with increasing amounts of LBG and subjected to an\\u000a intraluminal digestion procedure. Element binding was measured by eliminating the complexes by twofold centrifugation. Availability\\u000a of the elements was determined

Douwina Bosscher; Harry Robberecht; Rudy Van Cauwenbergh; Micheline Van Caillie-Bertrand; Hendrik Deelstra

2001-01-01

423

A solid state NMR study of locust bean gum galactomannan and Konjac glucomannan gels  

Microsoft Academic Search

This paper describes a 13C solid state NMR study of hydrated powders and gels of locust bean gum galactomannan-LBG and Konjac glucomannan-KGM. Changes in relative spectral intensities, cross-polarization dynamics (TCH, T1?H) and relaxation times (T1C, T1H, T2H) show that hydration (0–90%) of LBG powders increases the 108Hz frequency molecular motions, probably reflecting the enhanced motion of non-aggregating segments and chain

M. C. Vieira; A. M. Gil

2005-01-01

424

On the incompatibility of alkaline gelatin and locust bean gum in aqueous solution  

Microsoft Academic Search

The compatibility of gelatin with ‘high temperature’ and ‘low temperature’ fractions of locust bean gum (LBG) (LBGLTF and LBGHTF) as well as with whole LBG (LBGt) at pH=5, ionic strength (?)=0.002 \\/NaCl\\/ and 313K was studied. In the above conditions mannose\\/galactose ratio (MGR) of LBG molecules is an important factor controlling their compatibility with gelatin and the water distribution between

M. M. Alves; Yu. A. Antonov; M. P. Gonçalves

1999-01-01

425

Cascade analysis of mixed gels of xanthan and locust bean gum  

Microsoft Academic Search

The gel properties of xanthan (XG)–locust bean gum (LBG) mixtures were investigated. The concentration and temperature dependence of gel modulus, as well as the composition dependence of critical gelling concentration, were analyzed using a cascade model. The number of cross-linking sites per molecule for XG and LBG, fXG and fLBG, is determined by fitting experimental data to the model. The values

Ching-Feng Mao; Syang-Peng Rwei

2006-01-01

426

Immobilized growing lactic acid bacteria with ? -carrageenan — locust bean gum gel  

Microsoft Academic Search

Summary A cell entrapment process using ?-carrageenan — locust bean gum gel is presented. Streptococcus thermophilus, Lactobacillus bulgaricus and S. lactis were immobilized in small gel beads (0.5–1.0 mm and 1.0–2.0 mm diameter) and fermentations in bench bioreactors were conducted. Viability of entrapped cells, lactose utilization, lactic acid production and cell release rates were measured during fermentation. The procedure was

Pascal Audet; Céline Paquin; Christophe Lacroix

1988-01-01

427

Structure and rheology of the ?-carrageenan\\/locust bean gum gels  

Microsoft Academic Search

The structure and interaction of ?-carrageenan and locust bean gum (LBG) has been studied using rheology, cryo-SEM, conductivity and syneresis characterization. The rheological behaviour of the binary system has been characterized using both compression and shear measurements. Elimination of slip in the shear measurements yields G? values of the order 10,000–30,000Pa for a 1% ?-carrageenan gel in 0–0.2M added KCl.

D. E Dunstan; Y Chen; M.-L Liao; R Salvatore; D. V Boger; M Prica

2001-01-01

428

Effect of ?-carrageenan addition to dairy emulsions containing sodium caseinate and locust bean gum  

Microsoft Academic Search

Sodium caseinate-stabilized emulsions containing locust bean gum (LBG) were formulated to resemble soft-serve ice cream mixes, in order to study the effect of ?-carrageenan on the inhibition of phase separation in such systems. These emulsions behaved very different than skim milk powder (SMP)-stabilized emulsions, at similar protein concentration. Fat globule creaming was observed, due to depletion flocculation between sodium caseinate-coated

C. Vega; D. G. Dalgleish; H. D. Goff

2005-01-01

429

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

Microsoft Academic Search

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

Leif Lundin; Anne-Marie Hermansson

1995-01-01

430

Dilute solution properties of guar and locust bean gum in sucrose solutions  

Microsoft Academic Search

The dilute solution properties of guar, native and purified locust bean gum (LBG) in sucrose solutions (0–40% w\\/w) have been assessed. The intrinsic viscosity of LBG is artificially high due to a contribution from polymer\\/polymer associations. For both galactomannans, the addition of sucrose was shown to initially decrease the intrinsic viscosity, possibly due to either a reduction in solvent quality

Paul H Richardson; Juliette Willmer; Tim J Foster

1998-01-01

431

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

E-print Network

using the sessile drop method with a Kruss Drop Shape Analyser 100 device. Values 228 reported are the mean from at least ten measurements. 229 230 Filament measurements were obtained using automatic image treatment in the Cambridge Trimaster 231... of cake batters generated by planetary 598 mixing: Comparison between untreated and heat-treated wheat flours. Journal of Food 599 Engineering, 104, 592-602. 600 Miquelim, J. N., & Lannes, S. C. D. S. (2009). Egg albumin and guar gum influence on foam...

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

2014-03-06

432

Influence of locust bean gum on the rheological behaviour and microstructure of K-?-carrageenan  

Microsoft Academic Search

Mixtures of ?-carrageenan-locust bean gum (LBG) were analysed by transmission electron microscopy and dynamic viscoelastic measurements. The effect of two different mannose:galactose (M:G) ratios of LBG on the rheology and microstructure of ?-carrageenan in KCl was studied. The rheological differences observed in the mixed gel as LBGs were added were found to be dependent on M:G ratio, salt concentration and

Leif Lundin; Anne-Marie Hermansson

1995-01-01

433

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.

T.S., Priyanka

2014-01-01

434

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

435

Release properties on gelatin-gum arabic microcapsules containing camphor oil with added polystyrene  

Microsoft Academic Search

In this study, gelatin blended with arabic gum microcapsules containing camphor oil with added polystyrene were fabricated by a compound coacervation method. The parameters of oil\\/wall volume ratio, emulsification stirring speed, concentration of cross-linking agent, treated time and oil release properties were investigated. In order to improve the constant release effect of camphor oil, oil-soluble polystyrene (PS) was used as

Chih-Pong Chang; Ting-Kai Leung; Shang-Ming Lin; Che-Chang Hsu

2006-01-01

436

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

437

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

438

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

PubMed

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

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

2015-03-01

439

Synthesis and antioxidant properties of gum arabic-stabilized selenium nanoparticles.  

PubMed

Selenium nanoparticles (SeNPs) were prepared by using gum arabic (GA) as the stabilizer in a facile synthetic approach. The size, morphology, stability and antioxidant activity in vitro of the gum arabic-selenium nanocomposites (GA-SeNPs) were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier-transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) and ultraviolet-visible spectrophotometry (UV-vis). SeNPs (particle size of ?34.9 nm) can be stabilized in gum arabic aqueous solutions for approximately 30 days. FTIR results show that SeNPs were combined to the hydroxyl groups of GA. In the present work, the alkali-hydrolyzed GA (AHGA) was also prepared and its efficiency in stabilizing SeNPs was compared with GA. It was concluded that the branched structure of GA was a significant factor for the functionality. The hydroxyl radical scavenging ability and DPPH scavenging ability of GA-SeNPs were higher than those of AHGA-SeNPs and could reach 85.3±2.6%, 85.3±1.9% at a concentration of 4 mg/ml, respectively. PMID:24418338

Kong, Huiling; Yang, Jixin; Zhang, Yifeng; Fang, Yapeng; Nishinari, Katsuyoshi; Phillips, Glyn O

2014-04-01

440

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

441

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

442

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

443

A study of the neutral hydrogen in direction to the GUM nebula  

NASA Astrophysics Data System (ADS)

This paper presents 44 gray-scale maps at constant velocity of the distribution of H I in the direction of the Gum nebula. It is shown that there is no H I shell with a size comparable to the 36 deg diameter optical nebulosities and that there is a thick H I shell, about 7 deg in radius, shifted from the center of the optical nebula by more than 10 deg. The observations are consistent with a model in which the Gum nebula is the remnant of a supernova explosion that occurred about 2.6 million yr ago. The presence of two new H I bubbles associated with SWR 12 and 14, plus a possible one around WR 13, are disclosed from analysis of the H I gas distribution around the four WR star located beyond the Gum nebula. These H I bubbles have characteristics similar to those previously observed. Three shell-like objects probably related to OB stars and H II regions are also described.

Dubner, G.; Giacani, E.; Cappa de Nicolau, C.; Reynoso, E.

1992-12-01

444

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

445

A multifunctional magnetic nanocarrier bearing fluorescent dye for targeted drug delivery by enhanced two-photon triggered release  

Microsoft Academic Search

We report a novel nanoformulation for targeted drug delivery which utilizes nanophotonics through the fusion of nanotechnology with biomedical application. The approach involves an energy-transferring magnetic nanoscopic co-assembly fabricated of rhodamine B (RDB) fluorescent dye grafted gum arabic modified Fe3O4 magnetic nanoparticle and photosensitive linker by which dexamethasone drug is conjugated to the magnetic nano-assembly. The advantage offered by this

Shashwat S. Banerjee; Dong-Hwang Chen

2009-01-01

446

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

447

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

448

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

449

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

450

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

451

Evaluation of the binder effects of the gum mucilages of Cissus populnea and Acassia senegal on the mechanical properties of paracetamol tablets  

Microsoft Academic Search

A comparative study has been carried out to investigate the binder effects of the gums of Cissus populnea and Accasia senegal on the mechanical properties of paracetamol tablets. Tablet mechanical properties evaluated include the packing fraction (Pf), the tensile strength (T) and the brittle fracture tendency (BFI). Varying concentrations of the gum mucilage ranging from 1 - 15% (w\\/v) was

F. E. Eichie

2007-01-01

452

The addition of locust bean gum but not water delayed the gastric emptying rate of a nutrient semisolid meal in healthy subjects  

Microsoft Academic Search

BACKGROUND: Most of the previous studies regarding the effects of gel-forming fibres have considered the gastric emptying of liquid or solid meals after the addition of pectin or guar gum. The influence of locust bean gum, on gastric emptying of nutrient semisolid meals in humans has been less well studied, despite its common occurrence in foods. Using a standardised ultrasound

Gassan Darwiche; Ola Björgell; Lars-olof Almér

2003-01-01

453

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

454

Microwave assisted synthesis of guar gum grafted sodium acrylate/cloisite superabsorbent nanocomposites: reaction parameters and swelling characteristics.  

PubMed

In this study, superabsorbent nanocomposites of guar gum grafted sodium acrylate have been synthesized via both microwave and conventional techniques. The reaction parameters of both techniques were optimized and the microwave assisted method was proved to have higher grafting yield with lesser time of reaction as compared to the conventional method. X-ray diffraction and scanning electron microscopy analyses revealed that cloisite was exfoliated and uniformly dispersed in guar gum grafted sodium acrylate matrix. The results show that introducing cloisite into the guar gum grafted sodium acrylate network improved the swelling capability and the swelling rate of the superabsorbent nanocomposite was found to be enhanced at an optimal loading of 10% cloisite. The nanocomposites showed high water absorbency within a wide pH range. Preliminary studies on crystal violet dye removal showed promising results. PMID:24530336

Likhitha, M; Sailaja, R R N; Priyambika, V S; Ravibabu, M V

2014-04-01

455

GUM 48d: AN EVOLVED H II REGION WITH ONGOING STAR FORMATION  

SciTech Connect

High-mass star formation and the evolution of H II regions have a substantial impact on the morphology and star formation history of molecular clouds. The H II region Gum 48d, located in the Centaurus Arm at a distance of 3.5 kpc, is an old, well evolved H II region whose ionizing stars have moved off the main sequence. As such, it represents a phase in the evolution of H II regions that is less well studied than the earlier, more energetic, main-sequence phase. In this paper, we use multiwavelength archive data from a variety of sources to perform a detailed study of this interesting region. Morphologically, Gum 48d displays a ring-like faint H II region associated with diffuse emission from the associated photodissociation region, and is formed from part of a large, massive molecular cloud complex. There is extensive ongoing star formation in the region, at scales ranging from low to high mass, which is consistent with triggered star formation scenarios. We investigate the dynamical history and evolution of this region, and conclude that the original H II region was once larger and more energetic than the faint region currently seen. The proposed history of this molecular cloud complex is one of multiple, linked generations of star formation, over a period of 10 Myr. Gum 48d differs significantly in morphology and star formation from the other H II regions in the molecular cloud; these differences are likely the result of the advanced age of the region, and its different evolutionary status.

Karr, J. L.; Ohashi, N. [Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan (China); Manoj, P. [Department of Physics and Astronomy, University of Rochester, NY (United States)

2009-05-20

456

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

457

Effect of Encapsulating Nitrate in Sesame Gum on In vitro Rumen Fermentation Parameters.  

PubMed

Encapsulation is a method used to protect material from certain undesirable environments, for controlled release at a more favorable time and place. Animal productivity would be enhanced if feed additives are delivered to be utilized at their site of action, bypassing the rumen where they are likely to be degraded by microbial action. A novel method of encapsulation with sesame gum was used to coat nitrate, a known enteric methane mitigating agent, and tested for the effect on methane reduction and other in vitro fermentation parameters using rumen fluid from cannulated Hanwoo steers. Orchard grass was used as basal diet for fermentation. The treatments were matrix (1.1 g sesame gum+0.4 g sesame oil cake) only, encapsulated nitrate (matrix+nitrate [21 mM]), free nitrate (21 mM), and a control that contained no additive. Analyses of fermentation parameters were done at 0, 3, 6, 9, 12, 24, and 48 h time periods. In comparison to control, both free and encapsulated nitrate produced significantly reduced (p<0.01) methane (76% less) and also the total volatile fatty acids were reduced. A significantly higher (p<0.01) concentration of ammonia nitrogen was obtained with the encapsulated nitrate treatment (44%) compared to the free form (28%) and matrix only (20%) (p = 0.014). This might suggest slow release of encapsulated nitrate so that it is fully reduced to ammonia. Thus, this pioneering study found a significant reduction in methane production following the use of sesame gum encapsulated nitrate that shows the potential of a controlled release system in enhancing sustainability of ruminant production while reducing/eliminating the risk of nitrite toxicity. PMID:25358317

Mamvura, Chiedza Isabel; Cho, Sangbuem; Mbiriri, David Tinotenda; Lee, Hong-Gu; Choi, Nag-Jin

2014-11-01

458

5-fluorouracil loaded guar gum microspheres for colon delivery: preparation, characterization and in vitro release.  

PubMed

The present investigation is aimed to develop a new formulation containing chemically crosslinked guar gum microspheres loaded with 5-fluorouracil for targeting colorectal cancer. The emulsification polymerization method involving the dispersion of aqueous phase of guar gum in castor oil was used to prepare spherical microspheres. Various processing parameters were studied in order to optimize the formulation. Particle size and surface morphology of the microspheres were determined using optical microscopy and scanning electron microscopy. The in vitro drug release studies performed in simulated gastric fluid (SGF) for 2 h followed by intestinal fluid for 3 h, revealed the retention of the drug inside the microspheres from which only (15.27 +/- 0.56) % of the drug was released in 5 h. In vitro release rate studies were also carried out in simulated colonic fluid (SCF) in the presence of rat caecal contents, which showed improved drug release. The drug release from the formulation was found to be (41.6 +/- 3.5) % with 2% (w/v) caecal matter in 24 h as compared to control study where (25.2 +/- 3.5) % of drug was released. The drug release from the formulation with 2% and 4% rat caecal contents medium after 2 days of enzyme induction was found to be (56.3 +/- 4.1) % and (78.9 +/- 2.8) % in 24 h respectively. Similarly, (61.3 +/- 5.4) % and (90.2 +/- 2.9) % drug was released respectively with 2% and 4% rat caecal matter after 4 days of enzyme induction and (72.1 +/- 2.9) % and (90.2 +/- 3.2) % after 6 days of enzyme induction. In this way, 5-fluorouracil loaded guar gum microspheres have shown promising results in the management of colorectal cancer, warranting thorough in vivo study for scale up technology. PMID:21351727

Kaushik, Dinesh; Sardana, Satish; Mishra, D N

2009-11-01

459

Effect of Sugar-Free Gum in Addition to Tooth Brushing on Dental Plaque and Interdental Debris  

PubMed Central

Background: Chewing-gum may serve as an effective oral hygiene device when brushing may not be possible. The aim of the present study was to evaluate the effect of chewing sugar-free gum twice a day after meals in addition to tooth brushing on dental plaque and interdental debris. Methods Twenty four (12 males and 12 females aged 20-21 years) healthy third-year dental students participated in the study. It was a prospective single blind and non-randomized before and after study. The control group followed tooth brushing habit twice a day plus water rinsing after meals at noon and night for 10 days. The study group followed tooth brushing habit twice a day plus chewing one pellet of sugar-free gum after meals at noon and night for 30 minutes for 3 weeks. Personal hygiene performance index (PHP-M) was used to assess the dental plaque and self-designed interdental debris index for interdental debris. ANOVA, Tukey and ‘t’ tests were used for data analysis. The level of significance was fixed at ? = 0.05. Results: The baseline percentages of cumulative plaque and interdental debris were 63.12% and 76.44%, respectively. There was no significant difference in the plaque scores following either water rinsing (61.73%) or gum chewing (59.44%) after meals, but a statistically significant reduction of 14.18% in interdental debris was observed among those who chewed the gum (P < 0.05). Conclusion: After meal, gum chewing in addition to daily tooth brushing reduced interdental debris, but had no effect on established buccal and lingual dental plaques. PMID:22013459

Kakodkar, Pradnya; Mulay, Soniya

2010-01-01

460

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

461

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

462

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

463

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

464

Potential of guar gum microspheres for target specific drug release to colon.  

PubMed

Various approaches for colon targeted drug delivery have been studied over the last decade including, pro-drugs, timed-released systems, coating of pH-dependant polymer and the use of polysaccharides. In the present work, a novel formulation consisting of cross-linked microspheres of guar gum has been investigated for colon-targeted delivery of metronidazole. An emulsification method involving the dispersion of aqueous solution of guar gum in castor oil was used to prepare spherical microspheres. Process parameters were analyzed in order to optimize the formulation. Shape and surface morphology of the microspheres were examined using scanning electron microscopy. Placebo microspheres exhibited a smooth surface while the incorporation of drug imparted a slight roughness to the surface texture. Particle size of the microspheres was determined using laser diffraction particle size analyzer. The in vitro drug release studies were performed in simulated gastric fluid for 2 h and intestinal fluid for 3 h, which revealed that the drug was retained comfortably inside the microspheres and that only 15.27+/-0.56% of the drug was released in 5 h. In vitro release rate studies were also carried out in simulated colonic fluid (SCF) in the presence of rat cecal contents, which showed improved drug release. Moreover, to induce the enzymes that specifically act on guar gum, the rats were treated with 1 ml of 1% w/v dispersion of guar gum for 2, 4 and 6 days and release rate studies were repeated in SCF in the presence of 2 and 4% w/v of cecal matter. A marked improvement in the drug release was observed in presence of cecal matter obtained after induction when compared to those without induction. In vitro release studies exhibited 31.23+/-1.49% drug release in 24 h in dissolution medium without rat cecal matter. However, the incorporation of 4% w/v cecal matter obtained after 6 days of enzymes induction increased the drug release to 96.24+/-4.77%. PMID:15621668

Chourasia, M K; Jain, S K

2004-01-01

465

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

PubMed

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

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

2012-10-01

466

Randomized controlled trial to evaluate tooth stain reduction with nicotine replacement gum during a smoking cessation program  

PubMed Central

Background In addition to its general and periodontal health effects smoking causes tooth staining. Smoking cessation support interventions with an added stain removal or tooth whitening effect may increase motivation to quit smoking. Oral health professionals are well placed to provide smoking cessation advice and support to patients. The objective of the present study was to evaluate the effect of Nicorette® Freshmint Gum used in a smoking cessation programme administered in a dental setting, on extrinsic stain and tooth shade among smokers. Methods An evaluator-blinded, randomized, 12-week parallel-group controlled trial was conducted among 200 daily smokers motivated to quit smoking. Participants were randomised to use either the Nicorette® Freshmint Gum or Nicorette® Microtab (tablet). Tooth staining and shade were rated using the modified Lobene Stain Index and the Vita® Shade Guide at baseline, weeks 2, 6 and 12. To maintain consistency with other whitening studies, the primary end-point was the mean change in stain index between baseline and week 6. Secondary variables included changes in stain measurements and tooth shade at the other time points the number of gums or tablets used per day and throughout the trial period; and the number of cigarettes smoked per day. Treatments were compared using analysis of covariance (ANCOVA), using treatment and nicotine dependence as factors and the corresponding baseline measurement as a covariate. Each comparison (modified intention-to-treat) was tested at the 0.05 level, two-sided. Within-treatment changes from baseline were compared using a paired t-test. Results At week 6, the gum-group experienced a reduction in mean stain scores whilst the tablet-group experienced an increase with mean changes of -0.14 and +0.12 respectively, (p?=?0.005, ANCOVA). The change in mean tooth shade scores was statistically significantly greater in the gum-group than in the tablet group at 2 (p?=?0.015), 6 (p?=?0.011) and 12 weeks (p?=?0.003) with greater lightening in the gum-group at each examination period. Conclusion These results support the efficacy of the tested nicotine replacement gum in stain reduction and shade lightening. These findings may help dentists to motivate those wishing to quit smoking using a nicotine replacement gum. Trial registration NCT01440985 PMID:22695211

2012-01-01

467

Effect of urinary pH and nicotine excretion rate on plasma nicotine during cigarette smoking and chewing nicotine gum  

PubMed Central

1 Plasma nicotine levels produced by chewing nicotine gum were compared with those obtained by cigarette smoking under conditions of controlled urinary pH. 2 Although absorption was slower, plasma levels comparable to cigarette smoking were built up on 4 mg (but not 2 mg) nicotine gum. 3 Urinary excretion of nicotine was influenced markedly by pH and the rate of urine flow. 4 Plasma nicotine was higher under alkaline compared to acidic conditions (P < 0.001) but the rate of urinary nicotine excretion appeared to have little effect on the plasma level.

Feyerabend, C.; Russell, M. A. H.

1978-01-01

468

New intrinsic mechanism on gum-like superelasticity of multifunctional alloys  

NASA Astrophysics Data System (ADS)

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.

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

2013-07-01

469

Atomization of coal water mixtures: evaluation of fuel nozzles and a cellulose gum simulant  

SciTech Connect

An experimental evaluation of four air-assist fuel nozzles has been conducted to determine atomization levels of coal-water mixture (CWM) fuels at operating conditions simulating a high pressure combustor. Two of the nozzles were commercial units marketed for use in atmospheric burners, while two nozzles were specially designed for CWM operation in a high pressure combustor. Sprays from all four injectors were characterized in tests performed over a range of liquid and air flowrates. Most of the tests were performed using a cellulose-gum water solution prepared to match the viscosity and drip characteristics of an available CWM. Atomization data acquired from a limited test series using the CWM were found to be properly represented by the gum solution data. High levels of atomization (SMD 10 micron) were achieved by two of the nozzles - one commercial unit and one special unit - at an assist airflow level corresponding to a nozzle air-fuel ratio between 0.6 to 0.8. 4 references, 13 figures, 3 tables.

Rosfjord, T.J.

1984-11-01

470

Discovering young stars in the Gum 31 region with infrared observations  

E-print Network

Context. The Gum 31 bubble containing the stellar cluster NGC 3324 is a poorly-studied young region close to the Carina Nebula. Aims. We are aiming to characterise the young stellar and protostellar population in and around Gum 31 and to investigate the star-formation process in this region. Methods. We identify candidate young stellar objects from Spitzer, WISE, and Herschel data. Combining these, we analyse the spectral energy distributions of the candidate young stellar objects. With density and temperature maps obtained from Herschel data and comparisons to a 'collect and collapse' scenario for the region we are able to further constrain the characteristics of the region as a whole. Results. 661 candidate young stellar objects are found from WISE data, 91 protostar candidates are detected through Herschel observations in a 1.0 deg x 1.1 deg area. Most of these objects are found in small clusters or are well aligned with the H II bubble. We also identify the sources of Herbig-Haro jets. The infrared morpho...

Ohlendorf, Henrike; Gaczkowski, Benjamin; Ratzka, Thorsten; Ngoumou, Judith; Roccatagliata, Veronica; Grellmann, Rebekka

2013-01-01

471

Gum 48d: an evolved HII region with ongoing star formation  

E-print Network

High mass star formation and the evolution of HII regions have a substantial impact on the morphology and star formation history of molecular clouds. The HII region Gum 48d, located in the Centaurus Arm at a distance of 3.5 kpc, is an old, well evolved HII region whose ionizing stars have moved off the main sequence. As such, it represents a phase in the evolution of HII regions that is less well studied than the earlier, more energetic, main sequence phase. In this paper we use multi-wavelength archive data from a variety of sources to perform a detailed study of this interesting region. Morphologically, Gum 48d displays a ring-like faint HII region associated with diffuse emission from the associated PDR, and is formed from part of a large, massive molecular cloud complex. There is extensive ongoing star formation in the region, at scales ranging from low to high mass, which is consistent with triggered star formation scenarios. We investigate the dynamical history and evolution of this region, and conclude...

Karr, J L; Ohashi, N

2009-01-01

472

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

473

Ultrasound-assisted formation of the canthaxanthin emulsions stabilized by arabic and xanthan gums.  

PubMed

There is interest in incorporating canthaxanthin (CTX) into food emulsions due to its high potential health benefits. The used CTX in this study was produced by the bacterium of Dietzia natronolimnaea HS-1. Then, the influence of main emulsion components (gum arabic (GA), xanthan gum (XG) and coconut oil (CO)) on the surface-weighted mean diameter (D32), polydispersity index (PDI), specific surface area (SSA) of droplets and density of the emulsions containing CTX was optimized using response surface methodology (RSM). Polynomial equations between the responses and independent variables were derived. The linear effect of GA had a significant (p<0.0001) term in all reduced models. The optimal formulation for emulsions was composed of GA content of 9.85% (w/w), XG content of 0.13% (w/w) and CO concentration of 3.50% (w/w). This optimum formulation yielded D32 of 0.752 ?m, PDI of 1.533, SSA of 9.995 m(2)/ml and density of 1.0357 g/cm(3). PMID:23688450

Gharibzahedi, Seyed Mohammad Taghi; Razavi, Seyed Hadi; Mousavi, Seyed Mohammad

2013-07-01

474

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

475

Interactions between fluorinated cationic guar gum and surfactants in the dilute and semi-dilute solutions.  

PubMed

The interactions between the fluorinated cationic guar gum (FCGG) and ionic surfactants including cetyl trimethyl ammonium bromide (CTAB) and sodium lauryl sulfate (SDS) were studied by light scattering, fluorescence spectroscopy, UV-spectrophotometer, (19)F NMR and dynamic rheometer, respectively. The FCGG is prepared with cationic guar gum, isophorone diisocyanate and 2,2,3,4,4,4-hexafluoro-1-butanol. The results show that, with the addition of the surfactants, the stretching degree of the FCGG chains is increased in the FCGG/CTAB solutions, while the dramatical shrinking of FCGG chain, the phase separation and the re-stretched macromolecules appear successively because of the electricity neutralization reaction in the FCGG/SDS system. The mixed hydrophobic domains in all solutions will be reinforced and then dismantled. The solution elasticity shows up the maximum value accordingly. The surfactants can be embedded in the micro-domains and then hinder the fluorinated segmental motions. The interactions between FCGG and SDS are much stronger than those between FCGG and CTAB. PMID:24274554

Wang, Chen; Li, Xiaorui; Li, Peizhi; Niu, Yuhua

2014-01-01

476

Utility of in situ sodium alginate/karaya gum gels to facilitate gastric retention in rodents.  

PubMed

Target validation or demonstration of efficacy requires adequate in vivo exposure of tool molecules to determine their activity in order to validate the model or show the potential usefulness of the pharmacophore. Early discovery work is often carried out with compounds which possess undesirable PK properties in small rodents where the discovery formulation scientist is often forced to dose 2-4 times per day. Gastric retentive formulations in small rodents (rats/mice) could enable increased duration of exposure for compounds with narrow absorption windows or increased residence time for compounds with targets located in the GI tract. The aim of this work is to establish an easily administered gastric retentive gel for rodents in situ using a mixture of sodium alginate and karaya gum. Feasibility studies were conducted in Sprague-Dawley rats using barium sulfate as a radio-opaque tracer. The results show that gastric retention of barium was achieved for rats dosed with the gel formulation relative to a barium suspension. The gastric residence time of the gel varied from 1h to >8h (n=3). The data suggest that sodium alginate/karaya gum gels may be a useful tool to achieve gastric retention in rodent studies. PMID:22692076

Foster, Kimberly A; Morgen, Mike; Murri, Brice; Yates, Ian; Fancher, R Marcus; Ehrmann, Jon; Gudmundsson, Olafur S; Hageman, Michael J

2012-09-15

477

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

PubMed

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

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

2007-03-01

478

Allergic contact dermatitis caused by gum rosin and wood rosin in Tako-no-Suidashi ointment.  

PubMed

Tako-no-Suidashi ointment (TSO) is an old Japanese over-the-counter drug, used for the drainage of infectious pustular disease, such as furuncles, carbuncles and infectious atheroma, although whether it works well or not is unknown. The ingredients of the TSO compound commonly include rapeseed oil, gum rosin, wood rosin, Japanese wax, paraffin, petrolatum, copper sulfate, Peru balsam, acetic acid, salicylic acid and trace amounts of Guinea green B. We report a case of contact dermatitis in a 38-year-old Japanese woman caused by TSO. The patient presented to our hospital with pruritic erythema on her left cheek. In order to remove a subcutaneous tumor, she had applied TSO 4 days prior to presentation. Clinical examination showed a well-demarcated exudative erythematous macule with yellowish crusts and scales on her left cheek. Patch testing showed a positive reaction to TSO (++), gum rosin (++) and wood rosin (++) at 72 h. As TSO includes highly allergenic material, caution should be made in applying this topical therapy. PMID:21592201

Tsuruta, Daisuke; Sowa, Junko; Tsuruta, Kyoko; Ishii, Masamitsu; Kobayashi, Hiromi

2011-10-01

479

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

PubMed

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

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

2014-11-01

480

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