1
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Rheological characterization of the exopolysaccharide produced by Alteromonas macleodii Mo 169. Int J Biol Macromol 2023; 227:619-629. [PMID: 36539173 DOI: 10.1016/j.ijbiomac.2022.12.117] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 11/05/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022]
Abstract
Rheology modifiers are essential additives in numerous products in a variety of industries. Due to environmental awareness, consumer-oriented industries are interested in novel natural rheological agents that can replace synthetic chemicals. In this study, the chemical composition and rheological properties of a novel exopolysaccharide (EPS) produced by Alteromonas macleodii Mo 169 were investigated. It was mainly composed of uronic acids (50 mol%) and total carbohydrates were 17 % sulfated. The EPS viscosity increased with concentration, and a non-Newtonian shear thinning behavior was found for concentrations above 0.1 wt%. The elastic and viscous moduli indicated a weak gel-like structure above 0.4 wt%. It maintained its shear thinning behavior and viscoelastic properties in the presence of NaCl and CaCl2 for pH range 5-7 and temperatures up to 55 °C. Though the apparent viscosity decreased at pH 3 and 9 and temperatures above 65 °C, the shear thinning behavior was retained. The viscous and viscoelastic properties were recovered after heating (95 °C) and cooling (0 °C), indicating a good thermal stability and recoverability. After high shear force, the solution recovered original rheological properties within few seconds, demonstrating self-healing properties.
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2
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Ahmed J. Optimization of high-pressure-assisted xanthan gum dispersions for the maximization of rheological moduli: Application of time-pressure/ temperature superposition principle. Food Hydrocoll 2022. [DOI: 10.1016/j.foodhyd.2021.107080] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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3
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Dimopoulou M, Alba K, Sims IM, Kontogiorgos V. Structure and rheology of pectic polysaccharides from baobab fruit and leaves. Carbohydr Polym 2021; 273:118540. [PMID: 34560952 DOI: 10.1016/j.carbpol.2021.118540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 08/02/2021] [Accepted: 08/04/2021] [Indexed: 12/31/2022]
Abstract
Linkage patterns and relaxation dynamics of baobab (Adansonia digitata) polysaccharides have been investigated by means of linkage analysis and rheometry. The fruit polysaccharide was mostly xylogalacturonan, with co-extracted α-glucan. The leaf polysaccharide consists predominantly of two domains, one branched at O-4 of the →2)-Rhap-(1→ residues and another branched at O-3 of the →4)-GalpA-(1→ backbone to single GlcpA-(1→ residues. Master curves of viscoelasticity of fruit polysaccharides manifested strong pH-dependency. At pH below the dissociation constant of galacturonic acid, dispersions showed liquid-like behaviour. In contrast, at neutral pH, a weak gel network formation was observed that destabilised rapidly under the influence of flow fields. The present work identifies xylogalacturonans from baobab fruit as polysaccharides with unique rheological characteristics that may point to new directions in food and pharmaceutical formulation.
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Affiliation(s)
- Maria Dimopoulou
- School of Health and Life Sciences, Teesside University, Middlesbrough TS1 3BX, UK
| | - Katerina Alba
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane 4072, Queensland, Australia
| | - Ian M Sims
- The Ferrier Research Institute, Victoria University of Wellington, 69 Gracefield Road, Lower Hutt 5010, New Zealand
| | - Vassilis Kontogiorgos
- School of Agriculture and Food Sciences, The University of Queensland, Brisbane 4072, Queensland, Australia.
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4
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Rheological and Thickening Properties. Food Hydrocoll 2021. [DOI: 10.1007/978-981-16-0320-4_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5
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Moniri H, Farahmandfar R, Motamedzadegan A. Cress seed (
Lepidium sativum
) gum dried by vacuum, freeze, and microwave drying methods: Structural, rheological, emulsifying, and foaming properties. J FOOD PROCESS ENG 2020. [DOI: 10.1111/jfpe.13408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Hannaneh Moniri
- Department of Food Science and TechnologySari Agricultural Sciences and Natural Resources University Sari Iran
| | - Reza Farahmandfar
- Department of Food Science and TechnologySari Agricultural Sciences and Natural Resources University Sari Iran
| | - Ali Motamedzadegan
- Department of Food Science and TechnologySari Agricultural Sciences and Natural Resources University Sari Iran
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6
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Moniri H, Farahmandfar R, Motamedzadegan A. Investigation of hot air and foam-mat dried cress seed gum by FT-IR, zeta potential, steady shear viscosity, dynamic oscillatory behavior, and other physical properties. Food Sci Nutr 2020; 8:2143-2155. [PMID: 32328281 PMCID: PMC7174221 DOI: 10.1002/fsn3.1514] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 01/07/2020] [Accepted: 01/10/2020] [Indexed: 11/07/2022] Open
Abstract
The effects of different drying methods (hot air drying at 40, 60, and 80°C, and foam-mat drying) on the characteristics (FT-IR, zeta potential, conductivity, color, rheology, texture, and emulsifying) of extracted cress seed gum (CSG) have been investigated. The models described the rheological behavior of CSG with high R 2, but in general Herschel-Bulkley's model has higher values of R 2 and lower values of RMSE compared to the fitted models. The HD 80 has high amount of viscosity. This means that as the temperature rises, the gel network is getting stronger, and gums from the internal CSG sections have a stronger gel network. Results of strain sweep test demonstrated that storage ( G LVE ' ) and loss modulus ( G LVE ″ ) for all solutions except foam-mat drying in the linear area showed solid-like behavior. The parameters of strain sweep (Gf, τf, τy, G LVE ″ , G LVE ' , YLVE) increased with increasing temperatures. Frequency sweep test showed that storage ( G LVE ' ) was greater than loss modulus ( G LVE ″ ) and samples have a solid behavior but foam-mat drying exhibited liquid behavior. Increasing temperature has a direct impact on texture, so hardness and adhesion are increased consequently. Generally, CSG has good emulsifying and foaming characteristics, but no significant difference was observed.
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Affiliation(s)
- Hannaneh Moniri
- Department of Food Science and TechnologySari Agricultural Sciences and Natural Resources UniversitySariIran
| | - Reza Farahmandfar
- Department of Food Science and TechnologySari Agricultural Sciences and Natural Resources UniversitySariIran
| | - Ali Motamedzadegan
- Department of Food Science and TechnologySari Agricultural Sciences and Natural Resources UniversitySariIran
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7
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Brighenti M, Govindasamy-Lucey S, Jaeggi J, Johnson M, Lucey J. Behavior of stabilizers in acidified solutions and their effect on the textural, rheological, and sensory properties of cream cheese. J Dairy Sci 2020; 103:2065-2076. [DOI: 10.3168/jds.2019-17487] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 11/19/2019] [Indexed: 11/19/2022]
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8
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Farahmandfar R, Salahi MR, Asnaashari M. Flow behavior, thixotropy, and dynamic viscoelasticity of ethanolic purified basil ( Ocimum bacilicum L.) seed gum solutions during thermal treatment. Food Sci Nutr 2019; 7:1623-1633. [PMID: 31139375 PMCID: PMC6526669 DOI: 10.1002/fsn3.992] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/24/2018] [Accepted: 12/27/2018] [Indexed: 11/19/2022] Open
Abstract
During processing, foodstuffs may be treated at various thermal operations. Thus, this study investigated the functional properties and flow behavior at operation conditions to ensure safety and improve quality and stability at high temperatures and analyzed the ability of gum to be used in food formulation. The results showed that the purified basil seed gum (PBSG) solutions could beknown as non-Newtonian liquids with pseudoplastic behavior. Frequency sweep revealed the storage modulus (G') was higher than the loss modulus (G″) in the treatments. According to stress sweep, frequency sweep, complex viscosity (η *), and loss-tangent (tan δ) outcomes, mechanical spectra of PBSG were categorized as weak gels. Besides, concentration and temperature were effect on G' and G″. The results indicated that, in general, 1% PBSG-121°C had the maximum yield stress, consistency coefficient (k), extent of thixotropy, and the minimum values of flow behavior index. Also, 1% PBSG showed the highest G', G″, η *, yield stress values at the limit of the LVE range (τy), flow-point stress (τf), and corresponding modulus G f (G' = G″), and the lowest value of tan δ. Exhibiting distinctive rheological characteristics of PBSG makes it as a worthy hydrocolloid to use in food products, which use thermal processing.
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Affiliation(s)
- Reza Farahmandfar
- Department of Food Science & TechnologySari Agricultural Sciences & Natural Resources University (SANRU)SariIran
| | - Mohammad Reza Salahi
- Department of Food Science & TechnologyFerdowsi University of Mashhad (FUM)MashhadIran
| | - Maryam Asnaashari
- Department of Food Science & TechnologySari Agricultural Sciences & Natural Resources University (SANRU)SariIran
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9
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Alaeddini B, Koocheki A, Mohammadzadeh Milani J, Razavi SMA, Ghanbarzadeh B. Steady and dynamic shear rheological behavior of semi dilute Alyssum homolocarpum seed gum solutions: influence of concentration, temperature and heating-cooling rate. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2018; 98:2713-2720. [PMID: 29083478 DOI: 10.1002/jsfa.8765] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 10/24/2017] [Accepted: 10/24/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Alyssum homolocarpum seed gum (AHSG) solution exhibits high viscosity at low shear rates and has anionic features. However there is no information regarding the flow and dynamic properties of this gum in semi-dilute solutions. The present study aimed to investigate the dynamic and steady shear behavior of AHSG in the semi-dilute region. RESULTS The viscosity profile demonestrated a shear thinning behavior at all temperatures and concentrations. An increase in the AHSG concentration was acompanied by an increase in the pseudoplasticity degree, whereas, by increasing the temperature, the pseudoplasticity of AHSG decreased. At low gum concentration, solutions had more viscosity dependence on temperature. The mechanical spectra obtained from the frequency sweep experiment demonstrated viscoelastic properties for gum solutions. AHSG solutions showed typical weak gel-like behavior, revealing G' greater than G' within the experimental range of frequency (Hz), with slight frequency dependency. The influence of temperature on viscoelastic properties of AHSG solutions was studied during both heating (5-85 °C) and cooling (85-5 °C) processes. The complex viscosity of AHSG was greater compared to the apparent viscosity, indicating the disruption of AHSG network structure under continuous shear rates and deviation from the Cox-Merz rule. During the initial heating, the storage modulus showed a decreasing trend and, with a further increase in temperature, the magnitude of storage modulus increased. The influence of temperature on the storage modulus was considerable when a higher heating rate was applied. CONCLUSION AHSG can be applied as a thickening and stabilizing agents in food products that require good stability against temperature. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Behzad Alaeddini
- Department of Food Science and Technology, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Arash Koocheki
- Department of Food Science and Technology, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Jafar Mohammadzadeh Milani
- Department of Food Science and Technology, Sari Agricultural Sciences and Natural Resources University, Sari, Mazandaran, Iran
| | | | - Babak Ghanbarzadeh
- Department of Food Science and Technology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran
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10
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Chen L, Yang T, Song Y, Shu G, Chen H. Effect of xanthan-chitosan-xanthan double layer encapsulation on survival of Bifidobacterium BB01 in simulated gastrointestinal conditions, bile salt solution and yogurt. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2017.04.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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New studies on basil ( Ocimum bacilicum L.) seed gum: Part III – Steady and dynamic shear rheology. Food Hydrocoll 2017. [DOI: 10.1016/j.foodhyd.2015.12.020] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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12
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Liu S, Zhang H, Qiu X, Fang B, Lu Y, Zhai W, Wang L, Li K. Rheokinetic study of gel-breaking process of xanthan gum solution. J DISPER SCI TECHNOL 2017. [DOI: 10.1080/01932691.2017.1312433] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Shuang Liu
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Lab of Chemical Engineering Rheology, Research Center of Chemical Engineering, East China University of Science and Technology, Shanghai, China
| | - Hong Zhang
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Lab of Chemical Engineering Rheology, Research Center of Chemical Engineering, East China University of Science and Technology, Shanghai, China
| | - Xiaohui Qiu
- Langfang Filial of Research Institute of Petroleum Exploration and Development, Petro China, Langfang, China
| | - Bo Fang
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Lab of Chemical Engineering Rheology, Research Center of Chemical Engineering, East China University of Science and Technology, Shanghai, China
| | - Yongjun Lu
- Langfang Filial of Research Institute of Petroleum Exploration and Development, Petro China, Langfang, China
| | - Wen Zhai
- Langfang Filial of Research Institute of Petroleum Exploration and Development, Petro China, Langfang, China
| | - Liwei Wang
- Langfang Filial of Research Institute of Petroleum Exploration and Development, Petro China, Langfang, China
| | - Kejing Li
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Lab of Chemical Engineering Rheology, Research Center of Chemical Engineering, East China University of Science and Technology, Shanghai, China
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13
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Gillet S, Aguedo M, Petrut R, Olive G, Anastas P, Blecker C, Richel A. Structure impact of two galactomannan fractions on their viscosity properties in dilute solution, unperturbed state and gel state. Int J Biol Macromol 2017; 96:550-559. [DOI: 10.1016/j.ijbiomac.2016.12.057] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 12/19/2016] [Accepted: 12/21/2016] [Indexed: 11/29/2022]
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14
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de Morais Lima M, Carneiro LC, Bianchini D, Dias ARG, Zavareze EDR, Prentice C, Moreira ADS. Structural, Thermal, Physical, Mechanical, and Barrier Properties of Chitosan Films with the Addition of Xanthan Gum. J Food Sci 2017; 82:698-705. [DOI: 10.1111/1750-3841.13653] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 01/06/2017] [Accepted: 01/11/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Maria de Morais Lima
- Dept. of Agroindustrial Science and Technology; College of Agronomy Eliseu Maciel - Federal Univ. of Pelotas; Pelotas - RS Brazil
| | - Lucia Cesar Carneiro
- Dept. of Agroindustrial Science and Technology; College of Agronomy Eliseu Maciel - Federal Univ. of Pelotas; Pelotas - RS Brazil
| | - Daniela Bianchini
- Center of Chemical Sciences; Pharmaceutical and Food - Federal Univ. of Pelotas; Pelotas-RS Brazil
| | - Alvaro Renato Guerra Dias
- Dept. of Agroindustrial Science and Technology; College of Agronomy Eliseu Maciel - Federal Univ. of Pelotas; Pelotas - RS Brazil
| | - Elessandra da Rosa Zavareze
- Dept. of Agroindustrial Science and Technology; College of Agronomy Eliseu Maciel - Federal Univ. of Pelotas; Pelotas - RS Brazil
| | - Carlos Prentice
- School of Chemistry and Food; Federal Univ. of Rio Grande - FURG; Rio Grande - RS Brazil
| | - Angelita da Silveira Moreira
- Dept. of Agroindustrial Science and Technology; College of Agronomy Eliseu Maciel - Federal Univ. of Pelotas; Pelotas - RS Brazil
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15
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Ghoumrassi-Barr S, Aliouche D. A Rheological Study of Xanthan Polymer for Enhanced Oil Recovery. J MACROMOL SCI B 2016. [DOI: 10.1080/00222348.2016.1207544] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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16
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Causse B, Spadini L, Sarret G, Faure A, Travelet C, Madern D, Delolme C. Xanthan Exopolysaccharide: Cu(2+) Complexes Affected from the pH-Dependent Conformational State; Implications for Environmentally Relevant Biopolymers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:3477-3485. [PMID: 26824427 DOI: 10.1021/acs.est.5b03141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The conformational impact of environmental biopolymers on metal sorption was studied through Cu sorption on xanthan. The apparent Cu(2+) complexation constant (logK; Cu(2+) + L(-) ↔ CuL(+)) decreased from 2.9 ± 0.1 at pH 3.5 to 2.5 ± 0.1 at pH 5.5 (ionic strength I = 0.1). This behavior is in apparent contradiction with basic thermodynamics, as usually the higher the pH the more cations bind. Our combined titration, circular dichroism and dynamic light scattering study indicated that the change observed in Cu bond strength relates to a conformational change of the structure of xanthan, which generates more chelating sites at pH 3.5 than at pH 5.5. This hypothesis was validated by the fact that the Cu sorption constants on xanthan were always higher than those measured on a mixture of pyruvic and glucuronic acids (logK = 2.2), which are the two constitutive ligands present in the xanthan monomer. This study shows the role of the structural conformation of natural biopolymers in metal bond strength. This finding may help to better predict the fate of Cu and other metals in acidic environmental settings such as aquatic media affected by acid mine drainage, as well as peats and acidic soils, and to better define optimal conditions for bioremediation processes.
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Affiliation(s)
- Benjamin Causse
- LEHNA/ENTPE/UCB/CNRS UMR 5023, F-69518 Lyon, France
- ISTERRE/CNRS UMR 5275/Université Grenoble Alpes/IRD, F-38058 Grenoble, France
| | - Lorenzo Spadini
- ISTERRE/CNRS UMR 5275/Université Grenoble Alpes/IRD, F-38058 Grenoble, France
- LTHE/CNRS UMR 5564/Université Grenoble Alpes/IRD, F-38058 Grenoble, France
| | - Géraldine Sarret
- ISTERRE/CNRS UMR 5275/Université Grenoble Alpes/IRD, F-38058 Grenoble, France
| | - Adeline Faure
- ISTERRE/CNRS UMR 5275/Université Grenoble Alpes/IRD, F-38058 Grenoble, France
| | | | - Dominique Madern
- IBS/CNRS UMR 5075/Université Grenoble Alpes/CEA, F-38044 Grenoble, France
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17
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Zhang H, Fang B, Lu Y, Qiu X, Jin H, Liu Y, Wang L, Tian M, Li K. Rheological properties of water-soluble cross-linked xanthan gum. J DISPER SCI TECHNOL 2016. [DOI: 10.1080/01932691.2016.1169929] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Hong Zhang
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Lab of Chemical Engineering Rheology, Research Center of Chemical Engineering, East China University of Science and Technology, Shanghai, China
| | - Bo Fang
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Lab of Chemical Engineering Rheology, Research Center of Chemical Engineering, East China University of Science and Technology, Shanghai, China
| | - Yongjun Lu
- Langfang Filial of Research Institute of Petroleum Exploration and Development, Petro China, Langfang, China
| | - Xiaohui Qiu
- Langfang Filial of Research Institute of Petroleum Exploration and Development, Petro China, Langfang, China
| | - Hao Jin
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Lab of Chemical Engineering Rheology, Research Center of Chemical Engineering, East China University of Science and Technology, Shanghai, China
| | - Yuting Liu
- Langfang Filial of Research Institute of Petroleum Exploration and Development, Petro China, Langfang, China
| | - Liwei Wang
- Langfang Filial of Research Institute of Petroleum Exploration and Development, Petro China, Langfang, China
| | - Meng Tian
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Lab of Chemical Engineering Rheology, Research Center of Chemical Engineering, East China University of Science and Technology, Shanghai, China
| | - Kejing Li
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, Lab of Chemical Engineering Rheology, Research Center of Chemical Engineering, East China University of Science and Technology, Shanghai, China
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18
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Kamal MS, Sultan AS, Al-Mubaiyedh UA, Hussein IA. Review on Polymer Flooding: Rheology, Adsorption, Stability, and Field Applications of Various Polymer Systems. POLYM REV 2015. [DOI: 10.1080/15583724.2014.982821] [Citation(s) in RCA: 163] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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19
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Ahmad NH, Ahmed J, Hashim DM, Manap YA, Mustafa S. Oscillatory and steady shear rheology of gellan/dextran blends. JOURNAL OF FOOD SCIENCE AND TECHNOLOGY 2015; 52:2902-9. [PMID: 25892789 PMCID: PMC4397348 DOI: 10.1007/s13197-014-1330-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 03/06/2014] [Accepted: 03/14/2014] [Indexed: 10/25/2022]
Abstract
Oscillatory and steady shear rheology of gellan (G) and dextran (D) solution individually, and in blends (G/D ratio 1:1, 1:2, and 1:3 w/v) with a total hydrocolloid concentration of 3 % (w/v) were studied at 25 °C. Individually, 1.5 % dextran and 1.5 % gellan in solution exhibited Newtonian and non-Newtonian behavior, respectively. A blend of equal proportion of dextran and gellan (G/D = 1:1) exhibits a distinct gel point (G' = G″), and further addition of dextran in the blend (G/D = 1:2 and 1:3) resulted predominating liquid-like (G″ > G') behavior. A plot of G' vs G″ distinctly showed the gradual transition of the blend. Shear stress (τ)-shear rate ([Formula: see text]) data fitted well the Herschel-Bulkley model. The G/D blend exhibited shear thinning behavior with flow behavior index less than unity. The Cox-Merz rule did not fit well for the complex shear viscosity (η*) and apparent viscosity (η) of the blend.
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Affiliation(s)
- Nurul Hawa Ahmad
- />Halal Products Research Institute, Universiti Putra Malaysia, Putra Infoport, 43400 Serdang, Selangor Darul Ehsan Malaysia
| | - Jasim Ahmed
- />Food & Nutrition Program, Kuwait Institute for Scientific Research, P.O Box 24885, 13109 Safat, Kuwait
| | - Dzulkifly M. Hashim
- />Halal Products Research Institute, Universiti Putra Malaysia, Putra Infoport, 43400 Serdang, Selangor Darul Ehsan Malaysia
- />Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan Malaysia
| | - Yazid Abdul Manap
- />Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan Malaysia
| | - Shuhaimi Mustafa
- />Halal Products Research Institute, Universiti Putra Malaysia, Putra Infoport, 43400 Serdang, Selangor Darul Ehsan Malaysia
- />Bioprocessing and Biomanufacturing Research Centre, Faculty of Biotechnology and Biomolecular Science, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan Malaysia
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20
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Emam HE, Zahran M. Ag0 nanoparticles containing cotton fabric: Synthesis, characterization, color data and antibacterial action. Int J Biol Macromol 2015; 75:106-14. [DOI: 10.1016/j.ijbiomac.2014.12.050] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 12/15/2014] [Accepted: 12/19/2014] [Indexed: 11/15/2022]
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21
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Argin S, Kofinas P, Lo YM. The cell release kinetics and the swelling behavior of physically crosslinked xanthan–chitosan hydrogels in simulated gastrointestinal conditions. Food Hydrocoll 2014. [DOI: 10.1016/j.foodhyd.2014.02.018] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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22
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Sébastien G, Christophe B, Mario A, Pascal L, Michel P, Aurore R. Impact of purification and fractionation process on the chemical structure and physical properties of locust bean gum. Carbohydr Polym 2014; 108:159-68. [PMID: 24751260 DOI: 10.1016/j.carbpol.2014.02.092] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 02/24/2014] [Accepted: 02/28/2014] [Indexed: 11/29/2022]
Abstract
Crude locust bean gum (CLBG) was purified and fractionated into two parts: the first was obtained by solubilization in water at 25°C (GM25) and the second consisted in a further extraction at 80°C on the residual impoverished fraction (GM80). The complete structural characterization has shown that GM80 possessed relatively longer chain lengths than GM25, a slightly lower degree of galactose substitution and a somewhat sharper galactosyl distribution in substituted and unsubstituted regions. A physical behavior analysis was carried out on solubilization kinetics, viscosity, viscoelasticity and formation of associated gels with xanthan or carrageenan. The average structure of GM80 generated larger intra-chain, inter-chain and inter-molecular interactions, resulting in the appearance of a stronger network. Small structural differences therefore generated very different physical behaviors. This study thus allowed to establish, in a precise and complete manner, fractionation-purification-structure-function relationships of galactomannans extracted from carob.
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Affiliation(s)
- Gillet Sébastien
- University of Liège - Gembloux Agro-Bio Tech, Unit of Biological and Industrial Chemistry (CBI), 2, Passage des déportés, 5030 Gembloux, Belgium.
| | - Blecker Christophe
- University of Liège - Gembloux Agro-Bio Tech, Food Science and Formulation Department (SAF), 2, Passage des déportés, 5030 Gembloux, Belgium.
| | - Aguedo Mario
- University of Liège - Gembloux Agro-Bio Tech, Unit of Biological and Industrial Chemistry (CBI), 2, Passage des déportés, 5030 Gembloux, Belgium.
| | - Laurent Pascal
- University of Liège - Gembloux Agro-Bio Tech, Unit of Biological and Industrial Chemistry (CBI), 2, Passage des déportés, 5030 Gembloux, Belgium.
| | - Paquot Michel
- University of Liège - Gembloux Agro-Bio Tech, Unit of Biological and Industrial Chemistry (CBI), 2, Passage des déportés, 5030 Gembloux, Belgium.
| | - Richel Aurore
- University of Liège - Gembloux Agro-Bio Tech, Unit of Biological and Industrial Chemistry (CBI), 2, Passage des déportés, 5030 Gembloux, Belgium.
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23
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Formulation and in vitro evaluation of xanthan gum-based bilayered mucoadhesive buccal patches of zolmitriptan. Carbohydr Polym 2014; 101:1234-42. [DOI: 10.1016/j.carbpol.2013.10.072] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 10/14/2013] [Accepted: 10/21/2013] [Indexed: 11/24/2022]
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24
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Laneuville SI, Turgeon SL, Paquin P. Changes in the physical properties of xanthan gum induced by a dynamic high-pressure treatment. Carbohydr Polym 2013; 92:2327-36. [DOI: 10.1016/j.carbpol.2012.11.077] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 11/20/2012] [Accepted: 11/26/2012] [Indexed: 11/28/2022]
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25
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26
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Polymers for enhanced oil recovery: A paradigm for structure–property relationship in aqueous solution. Prog Polym Sci 2011. [DOI: 10.1016/j.progpolymsci.2011.05.006] [Citation(s) in RCA: 576] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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27
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Abu-Huwaij R, Obaidat RM, Sweidan K, Al-Hiari Y. Formulation and in vitro evaluation of xanthan gum or carbopol 934-based mucoadhesive patches, loaded with nicotine. AAPS PharmSciTech 2011; 12:21-7. [PMID: 21161460 PMCID: PMC3066338 DOI: 10.1208/s12249-010-9534-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Accepted: 10/22/2010] [Indexed: 11/30/2022] Open
Abstract
Bilayer nicotine mucoadhesive patches were prepared and evaluated to determine the feasibility of the formulation as a nicotine replacement product to aid in smoking cessation. Nicotine patches were prepared using xanthan gum or carbopol 934 as a mucoadhesive polymers and ethyl cellulose as a backing layer. The patches were evaluated for their thickness, weight and content uniformity, swelling behavior, drug-polymers interaction, adhesive properties, and drug release. The physicochemical interactions between nicotine and the polymers were investigated by Fourier transform infrared (FTIR) spectroscopy. Mucoadhesion was assessed using two-arm balance method, and the in vitro release was studied using the Franz cell. FTIR revealed that there was an acid base interaction between nicotine and carbopol as well as nicotine and xanthan. Interestingly, the mucoadhesion and in vitro release studies indicated that this interaction was strong between the drug and carbopol whereas it was weak between the drug and xanthan. Loading nicotine concentration to non-medicated patches showed a significant decrease in the mucoadhesion strength of carbopol patches and no significant effect on the mucoadhesion strength of xanthan patches. In vitro release studies of the xanthan patches showed a reasonable fast initial release profile followed by controlled drug release over a 10-h period.
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Affiliation(s)
| | - Rana M. Obaidat
- />Jordan University of Science and Technology, Irbid, Jordan
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28
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Wyatt NB, Liberatore MW. Rheology and viscosity scaling of the polyelectrolyte xanthan gum. J Appl Polym Sci 2009. [DOI: 10.1002/app.31093] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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29
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LO Y, ZIEGLER R, ARGIN-SOYSAL S, HSU C, WAGNER N. EFFECTS OF INTERMOLECULAR INTERACTIONS AND MOLECULAR ORIENTATION ON THE FLUX BEHAVIOR OF XANTHAN GUM SOLUTIONS DURING ULTRAFILTRATION. J FOOD PROCESS ENG 2009. [DOI: 10.1111/j.1745-4530.2007.00235.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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30
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Koga T, Tanaka F, Kaneda I, Winnik FM. Stress buildup under start-up shear flows in self-assembled transient networks of telechelic associating polymers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:8626-8638. [PMID: 19438184 DOI: 10.1021/la804227u] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The nonaffine transient network theory is used to study the time development of the shear and normal stresses under start-up shear flows in networks formed by self-assembled telechelic, hydrophobically modified water-soluble polymers. The initial slope, strain hardening, and overshoot of the shear stress are studied in detail in relation to the nonlinear tension-elongation curve of the elastically active chains in the network. The condition for the occurrence of strain hardening (upward deviation of the stress from the reference curve defined by the linear moduli) is found to be gamma > gammac(A), where gamma is the shear rate, gamma(c) is its critical value for strain hardening, and A is the amplitude of the nonlinear term in the tension of a chain. The critical shear rate gamma(c) is calculated as a function of A. It is approximately 6.3 (in the time unit of the reciprocal thermal dissociation rate) for a nonlinear chain with A = 10. The overshoot time t(max) when the stress reaches a maximum and the total deformation gamma(max) = gamma(t max) accumulated before the peak time are obtained in terms of the molecular parameters of the polymer chain. The maximum deformation gamma(max) turns out to depend weakly upon the shear rate gamma. The first and second normal stress differences are also studied on the basis of the exact numerical integration of the theoretical model by paying special attention to their overshoot, undershoot, and sign change as a function of the shear rate. These theoretical results are compared with recent rheological experiments of the solutions of telechelic hydrophobically modified poly(ethylene oxide)s carrying short branched alkyl chains (2-decyl-tetradecyl) at both ends.
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Affiliation(s)
- Tsuyoshi Koga
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto 615-8510, Japan
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31
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Zhang H, Nishinari K. Characterization of the conformation and comparison of shear and extensional properties of curdlan in DMSO. Food Hydrocoll 2009. [DOI: 10.1016/j.foodhyd.2008.11.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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32
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Xu C, Willför S, Holmlund P, Holmbom B. Rheological properties of water-soluble spruce O-acetyl galactoglucomannans. Carbohydr Polym 2009. [DOI: 10.1016/j.carbpol.2008.08.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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33
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34
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Xiao M, Frey MW. Rheological studies of the interactions in cellulose/ethylene diamine/salt systems. ACTA ACUST UNITED AC 2008. [DOI: 10.1002/polb.21564] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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35
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36
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Abstract
Seed galactomannans are vegetable, heterogeneous polysaccharides widely distributed in nature. Generally, they possess (1-->4)-linked D-mannopyranose (Man) main chains to which are attached (1-->6)-linked D-galactopyranosyl (Gal) units. The Man/Gal ratios differ from gum to gum, resulting in a change in structure, which, in turn, determines the various industrial applications of seed galactomannans. These materials are important in paper, textile, petroleum-drilling, pharmaceutics, food, cosmaceutics, and explosives industries. In this review, the biodiversified applicability of galactomannan gums is discussed, particularly with respect to structural aspects, properties, human consumption, and technical applications. Especially important is that the solution properties (rheological behaviour, viscosity, emulsifying tendency, etc.) of natural and chemically modified galactomannans can be tuned by interaction with other (carbohydrate-based) monomers or polymers.
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Affiliation(s)
- Manjoosha Srivastava
- Pharmacognosy Division, National Botanical Research Institute, Lucknow-226001, India
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37
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Physicochemical and rheological properties of a novel emulsifier, EPS-R, produced by the marine bacteriumHahella chejuensis. BIOTECHNOL BIOPROC E 2004. [DOI: 10.1007/bf02933066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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38
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Koenderink GH, Sacanna S, Aarts DGAL, Philipse AP. Rotational and translational diffusion of fluorocarbon tracer spheres in semidilute xanthan solutions. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2004; 69:021804. [PMID: 14995480 DOI: 10.1103/physreve.69.021804] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2003] [Indexed: 05/24/2023]
Abstract
We report an experimental study of rotational and translational diffusion and sedimentation of colloidal tracer spheres in semidilute solutions of the nonadsorbing semiflexible polymer xanthan. The tracers are optically anisotropic, permitting depolarized dynamic light scattering measurements without interference from the polymer background. The xanthan solutions behave rheologically like model semidilute polymeric solutions with long-lived entanglements. On the time scale of tracer motion the xanthan solutions are predominantly elastic. The generalized Stokes-Einstein relation describing the polymer solution as a continuous viscous fluid therefore severely overestimates the tracer hindrance. Instead, effective medium theory, describing the polymer solution as a homogeneous Brinkman fluid with a hydrodynamic screening length equal to the concentration-dependent static correlation length, is in excellent agreement with the tracer sedimentation and rotational diffusion coefficients. Rotational diffusion, however, is at the same time in good agreement with a simple model of a rotating sphere in a concentric spherical depletion cavity. Translational diffusion is faster than predicted for a Brinkman fluid, likely due to polymer depletion.
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Affiliation(s)
- Gijsberta H Koenderink
- Physics of Complex Systems, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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39
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Fang Y, Takahashi R, Nishinari K. Rheological characterization of schizophyllan aqueous solutions after denaturation-renaturation treatment. Biopolymers 2004; 74:302-15. [PMID: 15211499 DOI: 10.1002/bip.20081] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Schizophyllan (SPG) with a molecular weight of 2.6x10(6), designated SPG-1, is denatured and then renatured at a concentration of 1.8 wt % by alkalization-neutralization. The prepared denatured-renatured samples (DRSPG-1) are diluted to various concentrations and equilibrated for 10 days before rheological and intrinsic viscosity measurements. When concentration (C(p)) is above 0.75 wt %, DRSPG-1 aqueous systems have weak gel-type rheological properties. However, for 0.28 wt % <or= C(p) <or= 0.65 wt % and C(p) <or= 0.19 wt %, DRSPG-1 aqueous systems behave as power law fluids and Newtonian fluids, respectively, which are attributed to the moderate isotropy degree of DRSPG-1 chains. Furthermore, a critical overlap parameter of c*[eta] = 1.2 is determined for DRSPG-1 in aqueous solutions, which is close to that of 1 for intact SPG in water while far smaller than that of 4.3 for SPG in DMSO. This is considered to be due to the strong interactions of DRSPG-1 chains in water, further confirmed by the intrinsic viscosity measurements in which the DRSPG-1 aqueous solution shows an abnormally large value of Huggins constant. Regarding the structure of DRSPG-1 weak gels, multiruns of dynamic strain sweep measurements suggest that the dominant structures are aggregates formed by hydrogen-bonding associations of DRSPG-1 chains rather than the permanent three-dimensional network. In addition, the step-shear rate tests are performed to study the thixotropic properties of DRSPG-1 aqueous systems.
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Affiliation(s)
- Yapeng Fang
- Department of Food and Human Health Sciences, Graduate School of Human Life Science, Osaka City University, Sumiyoshi, Osaka, 558-8585, Japan
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40
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Associative and segregative interactions between gelatin and low-methoxy pectin: Part 1. Associative interactions in the absence of Ca2+. Food Hydrocoll 2003. [DOI: 10.1016/s0268-005x(03)00094-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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41
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Gilsenan P, Richardson R, Morris E. Associative and segregative interactions between gelatin and low-methoxy pectin. Part 3. Quantitative analysis of co-gel moduli. Food Hydrocoll 2003. [DOI: 10.1016/s0268-005x(03)00096-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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42
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Gorret N, Renard C, Famelart M, Maubois J, Doublier J. Rheological characterization of the EPS produced by P. acidi-propionici on milk microfiltrate. Carbohydr Polym 2003. [DOI: 10.1016/s0144-8617(02)00141-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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43
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Alonso-Mougán M, Meijide F, Jover A, Rodrı́guez-Núñez E, Vázquez-Tato J. Rheological behaviour of an amide pectin. J FOOD ENG 2002. [DOI: 10.1016/s0260-8774(02)00026-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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44
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45
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Ceulemans J, Vinckier I, Ludwig A. The use of xanthan gum in an ophthalmic liquid dosage form: rheological characterization of the interaction with mucin. J Pharm Sci 2002; 91:1117-27. [PMID: 11948550 DOI: 10.1002/jps.10106] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The development of an ocular dosage form containing xanthan gum and capable of interacting with mucin in the precorneal area is a challenge. The polymer concentration that can be applied is restricted because of the limited patient acceptability of highly viscous preparations. The precorneal mucin concentration is low and the high ionic strength of the lachrymal fluid forces xanthan gum in an ordered structure, less capable of interacting through heterotypic junctions. Intrinsic viscosity measurements and shear rheometry are used to investigate the effect of several factors (polymer concentration, additional boiling or sonication step to the preparation procedure) on the physicochemical properties of xanthan gum and the degree of interaction with a low (8%, w/v) and high (16.0%, w/v) concentrated mucin dispersion. Independent of the preparation procedure applied, a xanthan gum concentration of 1.0% (w/v) is required to obtain a measurable interaction with mucin. If an extra boiling or sonication step is added to the standard preparation procedure, the minimum mucin concentration necessary to achieve formation of heterotypic junctions is decreased. Only by sonication of the highly concentrated xanthan gum dispersion is the viscosity decreased to a level that is tolerable and comfortable to the patient. The findings of the present study clearly demonstrate that a significant interaction between a tolerable and comfortable ocular dosage form containing xanthan gum, and mucin 8% (w/v), is feasible after sonication of a highly concentrated polymer dispersion.
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Affiliation(s)
- Jens Ceulemans
- Department of Pharmaceutical Sciences, Laboratory of Pharmaceutical Technology and Biopharmacy, University of Antwerp (UIA), Universiteitsplein 1, B-2610 Antwerpen, Belgium
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46
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Abstract
The rheological properties of a moderately concentrated solution of xanthan gum in both the ordered and the disordered state have been studied. Oscillatory shear, steady shear flow, and extensional flow experiments have been performed at different temperatures, covering the order-disorder transition determined by differential scanning calorimetry (DSC). The principle of time/temperature superposition was applied to the xanthan solutions for the different types of flow. Although a master curve covering six decades of frequency could be obtained for the storage modulus over the entire investigated temperature range, less agreement was found for the other modulus. This indicates that the order-disorder transition reflects changes on the molecular scale and slight modification of the physical network structure. To the authors' knowledge, this is the first time that this transition has been observed using these different rheological techniques.
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Affiliation(s)
- E Pelletier
- North East Wales Institute, Centre for Water Soluble Polymers, PP 21, Plas Coch, Wrexham LL11 2AW, UK
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47
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Iseki T, Takahashi M, Hattori H, Hatakeyama T, Hatakeyama H. Viscoelastic properties of xanthan gum hydrogels annealed in the sol state. Food Hydrocoll 2001. [DOI: 10.1016/s0268-005x(01)00088-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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48
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Navarini L, Abatangelo A, Bertocchi C, Conti E, Bosco M, Picotti F. Isolation and characterization of the exopolysaccharide produced by Streptococcus thermophilus SFi20. Int J Biol Macromol 2001; 28:219-26. [PMID: 11251229 DOI: 10.1016/s0141-8130(01)00118-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This paper reports isolation, structural characterization and some physico-chemical properties in aqueous solution of the exopolysaccharide (EPS) produced by Streptococcus thermophilus strain SFi20. The yield of the purified EPS was found to be reproducible and close to the average value of 143 mg/l. The chemical structure, previously suggested, has been confirmed on the basis of NMR data. Viscometric, chiro-optical and rheological measurements have been carried out with the aim of characterizing the conformational state of the polysaccharide in aqueous solution. All the data reported indicate that the EPS does not undergo a cooperative conformational transition under the investigated experimental conditions. Furthermore, the viscosity data and the viscoelastic behaviour suggest that the polymer is rather flexible and adopts a random coil conformation in aqueous solution.
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Affiliation(s)
- L Navarini
- POLY-tech s.c.a.r.l., AREA Science Park, Padriciano 99, I-34012, Trieste, Italy.
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49
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Moreno J, Vargas MA, Madiedo JM, Muñoz J, Rivas J, Guerrero MG. Chemical and rheological properties of an extracellular polysaccharide produced by the cyanobacteriumAnabaena sp. ATCC 33047. Biotechnol Bioeng 2000. [DOI: 10.1002/(sici)1097-0290(20000205)67:3<283::aid-bit4>3.0.co;2-h] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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50
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Phenomenological theory describing the behaviour of non-freezing water in structure formation process of polysaccharide aqueous solutions. Carbohydr Polym 2000. [DOI: 10.1016/s0144-8617(99)00114-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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