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Golbek TW, Otto SC, Roeters SJ, Weidner T, Johnson CP, Baio JE. Direct Evidence That Mutations within Dysferlin's C2A Domain Inhibit Lipid Clustering. J Phys Chem B 2021; 125:148-157. [PMID: 33355462 DOI: 10.1021/acs.jpcb.0c07143] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mechanical stress on sarcolemma can create small tears in the muscle cell membrane. Within the sarcolemma resides the multidomain dysferlin protein. Mutations in this protein render it unable to repair the sarcolemma and have been linked to muscular dystrophy. A key step in dysferlin-regulated repair is the binding of the C2A domain to the lipid membrane upon increased intracellular calcium. Mutations mapped to this domain cause loss of binding ability of the C2A domain. There is a crucial need to understand the geometry of dysferlin C2A at a membrane interface as well as cell membrane lipid reorientation when compared to that of a mutant. Here, we describe a comparison between the wild-type dysferlin C2A and a mutation to the conserved aspartic acids in the domain binding loops. To identify both the geometry and the cell membrane lipid reorientation, we applied sum frequency generation (SFG) vibrational spectroscopy and coupled it with simulated SFG spectra to observe and quantify the interaction with a model cell membrane composed of phosphotidylserine and phosphotidylcholine. Observed changes in surface pressure demonstrate that calcium-bridged electrostatic interactions govern the initial interaction of the C2A domains docking with a lipid membrane. SFG spectra taken from the amide-I region for the wild type and variant contain features near 1642, 1663, and 1675 cm-1 related to the C2A domain β-sandwich secondary structure, indicating that the domain binds in a specific orientation. Mapping simulated SFG spectra to the experimentally collected spectra indicated that both wild-type and variant domains have nearly the same orientation to the membrane surface. However, examining the ordering of the lipids that make up a model membrane using SFG, we find that the wild type clusters the lipids as seen by the increase in the ratio of the CD3 and CD2 symmetric intensities by 170% for the wild type and by 120% for the variant. This study highlights the capabilities of SFG to probe with great detail biological mutations in proteins at cell membrane interfaces.
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Affiliation(s)
| | - Shauna C Otto
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon 97331, United States
| | - Steven J Roeters
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
| | - Colin P Johnson
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon 97331, United States
| | - Joe E Baio
- School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon 97331, United States
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2
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Románszki L, Hianik T, Keresztes Z. Plasmin determination based on enzymatic digestion of a β-casein layer at the air/water interface. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2020.125786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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3
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Koepf E, Richert M, Braunschweig B, Schroeder R, Brezesinski G, Friess W. Impact of formulation pH on physicochemical protein characteristics at the liquid-air interface. Int J Pharm 2018; 541:234-245. [DOI: 10.1016/j.ijpharm.2018.02.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 02/05/2018] [Accepted: 02/06/2018] [Indexed: 12/31/2022]
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4
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Notorious but not understood: How liquid-air interfacial stress triggers protein aggregation. Int J Pharm 2018; 537:202-212. [DOI: 10.1016/j.ijpharm.2017.12.043] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/21/2017] [Accepted: 12/22/2017] [Indexed: 11/23/2022]
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5
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The film tells the story: Physical-chemical characteristics of IgG at the liquid-air interface. Eur J Pharm Biopharm 2017; 119:396-407. [DOI: 10.1016/j.ejpb.2017.07.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 05/15/2017] [Accepted: 07/13/2017] [Indexed: 01/06/2023]
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6
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Morales R, Martínez KD, Pizones Ruiz-Henestrosa VM, Pilosof AMR. Modification of foaming properties of soy protein isolate by high ultrasound intensity: Particle size effect. ULTRASONICS SONOCHEMISTRY 2015; 26:48-55. [PMID: 25619451 DOI: 10.1016/j.ultsonch.2015.01.011] [Citation(s) in RCA: 136] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 11/10/2014] [Accepted: 01/09/2015] [Indexed: 05/13/2023]
Abstract
The effect of high intensity ultrasound (HIUS) may produce structural modifications on proteins through a friendly environmental process. Thus, it can be possible to obtain aggregates with a determined particle size, and altering a defined functional property at the same time. The objective of this work was to explore the impact of HIUS on the functionality of a denatured soy protein isolate (SPI) on foaming and interfacial properties. SPI solutions at pH 6.9 were treated with HIUS for 20 min, in an ultrasonic processor at room temperature, at 75, 80 and 85°C. The operating conditions were: 20 kHz, 4.27 ± 0.71 W and 20% of amplitude. It was determined the size of the protein particles, before and after the HIUS treatment, by dynamic light scattering. It was also analyzed the interfacial behavior of the different systems as well as their foaming properties, by applying the whipping method. The HIUS treatment and HIUS with temperature improved the foaming capacity by alteration of particle size whereas stability was not modified significantly. The temperature of HIUS treatment (80 and 85°C) showed a synergistic effect on foaming capacity. It was found that the reduction of particle size was related to the increase of foaming capacity of SPI. On the other hand, the invariable elasticity of the interfacial films could explain the stability of foams over time.
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Affiliation(s)
- Rocío Morales
- Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Karina D Martínez
- Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina.
| | - Víctor M Pizones Ruiz-Henestrosa
- Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Ana M R Pilosof
- Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina
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7
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Protein conformational transitions at the liquid-gas interface as studied by dilational surface rheology. Adv Colloid Interface Sci 2014; 206:222-38. [PMID: 24238394 DOI: 10.1016/j.cis.2013.10.024] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Revised: 10/21/2013] [Accepted: 10/21/2013] [Indexed: 11/21/2022]
Abstract
Experimental results on the dynamic dilational surface elasticity of protein solutions are analyzed and compared. Short reviews of the protein behavior at the liquid-gas interface and the dilational surface rheology precede the main sections of this work. The kinetic dependencies of the surface elasticity differ strongly for the solutions of globular and non-globular proteins. In the latter case these dependencies are similar to those for solutions of non-ionic amphiphilic polymers and have local maxima corresponding to the formation of the distal region of the surface layer (type I). In the former case the dynamic surface elasticity is much higher (>60 mN/m) and the kinetic dependencies are monotonical and similar to the data for aqueous dispersions of solid nanoparticles (type II). The addition of strong denaturants to solutions of bovine serum albumin and β-lactoglobulin results in an abrupt transition from the type II to type I dependencies if the denaturant concentration exceeds a certain critical value. These results give a strong argument in favor of the preservation of the protein globular structure in the course of adsorption without any denaturants. The addition of cationic surfactants also can lead to the non-monotonical kinetic dependencies of the dynamic surface elasticity indicating destruction of the protein tertiary and secondary structures. The addition of anionic surfactants gives similar results only for the protein solutions of high ionic strength. The influence of cationic surfactants on the local maxima of the kinetic dependencies of the dynamic surface elasticity for solutions of a non-globular protein (β-casein) differs from the influence of anionic surfactants due to the heterogeneity of the charge distribution along the protein chain. In this case one can use small admixtures of ionic surfactants as probes of the adsorption mechanism. The effect of polyelectrolytes on the kinetic dependencies of the dynamic surface elasticity of protein solutions is weaker than the effect of conventional surfactants but exceeds the error limits.
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8
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Dan A, Wüstneck R, Krägel J, Aksenenko EV, Fainerman VB, Miller R. Interfacial adsorption and rheological behavior of β-casein at the water/hexane interface at different pH. Food Hydrocoll 2014. [DOI: 10.1016/j.foodhyd.2012.10.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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9
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Tamm F, Sauer G, Scampicchio M, Drusch S. Pendant drop tensiometry for the evaluation of the foaming properties of milk-derived proteins. Food Hydrocoll 2012. [DOI: 10.1016/j.foodhyd.2011.10.013] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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10
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Surface dilatational behavior of β-casein at the solution/air interface at different pH values. Colloids Surf A Physicochem Eng Asp 2012. [DOI: 10.1016/j.colsurfa.2012.03.050] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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11
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β-Casein–phospholipid monolayers as model systems to understand lipid–protein interactions in the milk fat globule membrane. Int Dairy J 2012. [DOI: 10.1016/j.idairyj.2011.08.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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12
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Ma H, Forssell P, Partanen R, Buchert J, Boer H. Charge modifications to improve the emulsifying properties of whey protein isolate. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:13246-13253. [PMID: 22060038 DOI: 10.1021/jf203240e] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Whey protein isolate was modified by ethylene diamine in order to shift its isoelectric point to an alkaline pH. The extent of the modification was studied using SDS-PAGE and MALDI-TOF mass spectrometry. The modified whey proteins were used as an emulsifier to stabilize oil-in-water emulsions at acidic and neutral pH ranges, and their emulsifying properties were compared with that of the unmodified whey proteins and with the previously studied ethylene diamine modified sodium caseinate. The emulsifying activity of the modified whey proteins was similar to that of the unmodified ones, but the stability of an emulsion at pH 5 was significantly improved after the modification. Charge and coverage of droplet surface and the displacement of the interfacial proteins by surfactant Tween 20 were further studied as a function of pH. As compared with the unmodified whey proteins, the modified ones were proven to cover the interface more efficiently with extensive surface charge at pH 5, although the interfacial layer was less resistant to the surfactant displacement.
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Affiliation(s)
- Hairan Ma
- VTT Technical Research Centre of Finland, PO Box 1000, FI-02044 VTT, Finland
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13
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Minones Conde M, Conde O, Trillo JM, Minones J. Interactions in Monolayers: A Study of the Behavior of Poly(methyl methacrylate)–Lysozyme Mixed Films from Surface Pressure–Area and Ellipsometric Measurements. J Phys Chem B 2011; 115:8667-78. [DOI: 10.1021/jp109111k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Minones Conde
- Department of Physical Chemistry, Faculty of Pharmacy and ‡Department of Optometry, School of Optics and Optometry, University of Santiago de Compostela, Campus Sur., 15706-Santiago de Compostela, Spain
| | - O. Conde
- Department of Physical Chemistry, Faculty of Pharmacy and ‡Department of Optometry, School of Optics and Optometry, University of Santiago de Compostela, Campus Sur., 15706-Santiago de Compostela, Spain
| | - J. M. Trillo
- Department of Physical Chemistry, Faculty of Pharmacy and ‡Department of Optometry, School of Optics and Optometry, University of Santiago de Compostela, Campus Sur., 15706-Santiago de Compostela, Spain
| | - J. Minones
- Department of Physical Chemistry, Faculty of Pharmacy and ‡Department of Optometry, School of Optics and Optometry, University of Santiago de Compostela, Campus Sur., 15706-Santiago de Compostela, Spain
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14
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Development of the magnetic beads for dye ligand affinity chromatography and application to magnetically stabilized fluidized bed system. Process Biochem 2010. [DOI: 10.1016/j.procbio.2009.12.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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16
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Messina PV, Ruso JM, Prieto G, Fernández-Leyes MD, Schulz PC, Sarmiento F. Ca2+- and Mg2+-induced molecular interactions in a dehydrocholic acid/didodecyldimethylammonium bromide mixed monolayer. Colloid Polym Sci 2010. [DOI: 10.1007/s00396-009-2170-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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17
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Abascal DM, Gracia-Fadrique J. Surface tension and foam stability of commercial calcium and sodium caseinates. Food Hydrocoll 2009. [DOI: 10.1016/j.foodhyd.2009.02.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Caro AL, Rodríguez Niño MR, Rodríguez Patino JM. Dynamics of penetration of dipalmitoyl-phosphatidyl-choline (DPPC) monolayers by β-casein. Colloids Surf A Physicochem Eng Asp 2009. [DOI: 10.1016/j.colsurfa.2009.03.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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19
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Rodríguez Niño MR, Lucero A, Rodríguez Patino JM. Relaxation phenomena in phospholipid monolayers at the air–water interface. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2008.02.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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20
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21
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Cicuta P. Compression and shear surface rheology in spread layers of β-casein and β-lactoglobulin. J Colloid Interface Sci 2007; 308:93-9. [PMID: 17234202 DOI: 10.1016/j.jcis.2006.12.056] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Revised: 12/04/2006] [Accepted: 12/08/2006] [Indexed: 11/30/2022]
Abstract
We investigate the surface viscoelasticity of beta-lactoglobulin and beta-casein spread surface monolayers using a recently discovered method. Step compressions are performed, and the surface pressure is measured as a function of time. This is a common experiment for surface monolayers. However in our experiments the pressure is recorded by two perpendicular sensors, parallel and perpendicular to the compression direction. This enables us to clearly measure the time relaxation of both the compression and shear moduli, at the same time, in a single experiment, and with a standard apparatus. beta-Lactoglobulin and beta-casein monolayers are interesting because of their importance in food science and because they exhibit universally slow dynamical behavior that is still not fully understood. Our results confirm that the compressional modulus dominates the total viscoelastic response in both proteins. Indeed for beta-casein we confirm that the shear modulus is always negligible, i.e., the layer is in a fluid state. In beta-lactoglobulin a finite shear modulus emerges above a critical concentration. We emphasize that in Langmuir trough dynamic experiments the surface pressure should be measured in both the compression and the perpendicular directions.
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Affiliation(s)
- Pietro Cicuta
- Cavendish Laboratory and Nanoscience Center, J.J. Thomson Avenue, Cambridge CB3 0HE, UK.
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22
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Phospholipids and hydrolysates from a sunflower protein isolate adsorbed films at the air–water interface. Food Hydrocoll 2007. [DOI: 10.1016/j.foodhyd.2006.03.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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23
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Modifications of the charges at the N-terminus of bovine β-casein: Consequences on its structure and its micellisation. Food Hydrocoll 2007. [DOI: 10.1016/j.foodhyd.2006.03.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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24
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Vernoux N, Granjon T, Marcillat O, Besson F, Vial C. Interfacial behavior of cytoplasmic and mitochondrial creatine kinase oligomeric states. Biopolymers 2006; 81:270-81. [PMID: 16283667 DOI: 10.1002/bip.20412] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Adsorption to the air/water interface of isoenzymes of creatine kinase was investigated using surface pressure-area isotherms and Brewster angle microscopy (BAM) observations. Octameric mitochondrial creatine kinase (mtCK) exhibits a significant affinity for the air/water interface. Whatever the mode of formation of the interfacial film, i.e., injection of the protein in the subphase or spreading onto the buffer surface, the final arrangement and conformation adopted by mtCK molecules lead to a similar result. In contrast, the dimeric isoenzymes mtCK and cytosolic MMCK do not induce any surface pressure variation. However, when the subphase contains 0.3M NaCl, both isoenzymes adsorb to the interface. When treated with 0.8 or 3M GdnHCl, muscle creatine kinase (MMCK) becomes surface active and occupies a greater surface than mtCK. This result contrasts with previous observations, often derived from monomeric proteins, that their surface activity is increased upon unfolding. It underlines the possible influence exerted by the protein oligomeric state on its interfacial activity. At a subphase pH of 8.8, which corresponds to the pI of octameric mtCK, the profiles of the isotherms obtained with dimeric and octameric states and the resistance to compression of the protein monolayers are significantly affected when compared to those recorded at pH 7.4. These data suggest that the octamer is more hydrophobic than the dimer and may contribute to explaining why octamers bind to the inner mitochondrial membrane while dimers do not.
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Affiliation(s)
- Nathalie Vernoux
- UMR CNRS 5013, Biomembranes et enzymes associés, Université Claude Bernard Lyon I, 43, boulevard du 11 Novembre 1918, 69622 Villeurbanne cedex, France
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25
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Fernández MC, Sánchez CC, Rodríguez Niño MR, Rodríguez Patino JM. The Effect of Monoglycerides on Structural and Topographical Characteristics of Adsorbed β-Casein Films at the Air−Water Interface. Biomacromolecules 2006; 7:507-14. [PMID: 16471923 DOI: 10.1021/bm050733h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effect of monoglycerides (monopalmitin and monoolein) on the structural and topographical characteristics of beta-casein adsorbed film at the air-water interface has been analyzed by means of surface pressure (pi)-area (A) isotherms and Brewster angle microscopy (BAM). At surface pressures lower than that for the beta-casein collapse (pi(c)(beta-casein)), attractive interactions between beta-casein and monoglycerides were observed. At higher surface pressures, the collapsed beta-casein is partially displaced from the interface by monoglycerides. However, beta-casein displacement by monoglycerides is not quantitative at the monoglyceride concentrations studied in this work. From the results derived from these experiments, we have concluded that interactions, miscibility, and displacement of proteins by monoglycerides in adsorbed mixed monolayers at the air-water interface depend on the particular protein-monoglyceride system, the interactions between film-forming components being higher for adsorbed than for spread films. The adsorbed films are more segregated than spread films, and both collapsed protein domains and monoglyceride domains in adsorbed films are smaller than for spread films.
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Affiliation(s)
- Marta Cejudo Fernández
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/. Prof. García González 1, 41012-Seville, Spain
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26
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Castellani O, Belhomme C, David-Briand E, Guérin-Dubiard C, Anton M. Oil-in-water emulsion properties and interfacial characteristics of hen egg yolk phosvitin. Food Hydrocoll 2006. [DOI: 10.1016/j.foodhyd.2005.02.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Baeza R, Pilosof AMR, Sanchez CC, Rodríguez Patino JM. Adsorption and rheological properties of biopolymers at the air-water interface. AIChE J 2006. [DOI: 10.1002/aic.10855] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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28
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Pérez OE, Sánchez CC, Rodríguez Patino JM, Pilosof AMR. Thermodynamic and Dynamic Characteristics of Hydroxypropylmethylcellulose Adsorbed Films at the Air−Water Interface. Biomacromolecules 2005; 7:388-93. [PMID: 16398540 DOI: 10.1021/bm050757o] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Surface pressure isotherms and structural and surface dilatational properties of three hydroxypropylmethycelluloses (HPMCs, called E4M, E50LV, and F4M) adsorbed films at the air-water interface were determined. In this work we present evidence that HPMC molecules are able to diffuse and saturate the air-water interface at very low concentrations in the bulk phase. As bulk concentration increased, structural changes at a molecular level occurred at the interface. These changes corresponded to transition from an expanded structure (structure I) to a condensed one (structure II). When the surface concentration of HPMC was high enough, the collapse of the monolayer was observed. The three HPMCs formed very elastic films at the air-water interface, even at low surface pressures. E4M showed features that make it unique. For instance it showed the highest surface activity, mainly at low bulk concentrations (<10(-4) wt %). The differences observed in surface activity may be attributed to differences in the hydroxypropyl molar substitution and molecular weight of HPMC. All three HPMCs formed films of similar viscoelasticity and elastic dilatational modulus, which can be accounted for by their similar degree of methyl substitution.
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Affiliation(s)
- Oscar E Pérez
- Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria (1428), Buenos Aires, Argentina
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Conde JM, Rodríguez Patino JM, Trillo JM. Structural Characteristics of Hydrolysates of Proteins from Extracted Sunflower Flour at the Air−Water Interface. Biomacromolecules 2005; 6:3137-45. [PMID: 16283738 DOI: 10.1021/bm050469s] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The structural and topographical characteristics of a sunflower protein isolate (SPI) and its hydrolysates at different degrees of hydrolysis (DH = 5.62%, 23.5%, and 46.3%) spread at the air-water interface at pH 7 and 20 degrees C were determined from pi-A isotherms coupled with Brewster angle microscopy (BAM). The structural characteristics of SP hydrolysate spread monolayers depend on the degree of hydrolysis. We observed a significant shift of the pi-A(APPARENT) isotherms toward lower molecular areas as the degree of hydrolysis (DH) increased. This phenomenon was attributed to spreading of the protein at the interface, especially at DH 46.3%. A change in the monolayer structure was observed at a surface pressure of 12-15 mN/m. At a microscopic level, the heterogeneous monolayer structures visualized near the monolayer collapse and during the monolayer expansion proved the existence of large regions of protein aggregates. Reflectivity increased with surface pressure and was a maximum at the monolayer collapse. The monolayer thickness decreased as the degree of hydrolysis increased. These phenomena explain the poor functional properties for the formation and stabilization of a dispersion (emulsion or foam) of protein hydrolysates at high degrees of hydrolysis.
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Affiliation(s)
- José Miñones Conde
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/. Prof. García González, 1, 41012-Sevilla
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Abstract
Casein is well known as a good protein emulsifier and beta-casein is the major component of casein and commercial sodium caseinate. Dye affinity adsorption is increasingly used for protein separation. beta-Casein adsorption onto Reactive Red 120 attached magnetic poly(2-hydroxyethyl methacrylate) (m-PHEMA) beads was investigated in this work. m-PHEMA beads (80-120 microm in diameter) were produced by dispersion polymerization. The dichlorotriazine dye Reactive Red 120 was attached covalently as a ligand. The dye attached beads, having a swelling ratio of 55% (w/w) and carrying different amounts of Reactive Red 120 (9.2 micromol . g(-1)-39.8 micromol . g(-1)), were used in beta-casein adsorption studies. The effects of the initial concentration, pH, ionic strength and temperature on the adsorption efficiency of dye attached beads were studied in a batch reactor. The non-specific adsorption on the m-PHEMA beads was 1.4 mg . g(-1). Reactive Red 120 attachment significantly increased the beta-casein adsorption up to 37.3 mg . g(-1). More than 95.4% of the adsorbed beta-casein was desorbed in 1 h in a desorption medium containing 1.0 M KSCN at pH 8.0. We concluded that Reactive Red 120 attached m-PHEMA beads can be applied for beta-casein adsorption without significant losses in the adsorption capacities.
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Affiliation(s)
- Sinan Akgöl
- Department of Chemistry, Biochemistry Division, Adnan Menderes University, Aydin, Turkey.
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31
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Sánchez CC, Rodríguez Niño MR, Caro AL, Rodríguez Patino JM. Biopolymers and emulsifiers at the air–water interface. Implications in food colloid formulations. J FOOD ENG 2005. [DOI: 10.1016/j.jfoodeng.2004.05.065] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Maldonado-Valderrama J, Gálvez-Ruiz MJ, Martín-Rodríguez A, Cabrerizo-Vílchez MA. Adsorbed and spread beta-casein monolayers at oil-water interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:6093-6095. [PMID: 15248688 DOI: 10.1021/la0498307] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A previous study (Langmuir 2003, 19, 8436) used a Langmuir type pendant drop film balance to form beta-casein monolayers at the air-water interface. The present paper reports the application of that technique to the formation of protein monolayers at liquid interfaces. This technique allows a direct comparison between spread and adsorbed beta-casein interfacial behaviors that is presented in terms of their pi-A isotherms and static elasticity moduli. Pi-A isotherms of adsorbed and spread protein have been compared and found to be fairly similar in shape, stability, and also hysteresis phenomena. Examination of the elasticity moduli of both layers shows a similar analogy although slight differences arise and are interpreted in terms of the protein unfolding extent attained by both procedures at the oil interface.
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Affiliation(s)
- Julia Maldonado-Valderrama
- Biocolloids and Fluid Physics Group, Department of Applied Physics, University of Granada, E-18071 Granada, Spain
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Gonçalves da Silva AM, Romão RS, Lucero Caro A, Rodríguez Patino JM. Memory effects on the interfacial characteristics of dioctadecyldimethylammonium bromide monolayers at the air–water interface. J Colloid Interface Sci 2004; 270:417-25. [PMID: 14697709 DOI: 10.1016/j.jcis.2003.11.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The structural and dynamic characteristics of dioctadecyldimethylammonium bromide (DODAB) monolayers on a pure water subphase were investigated by surface film balance, Brewster angle microscopy, and relaxation in area and surface pressure at constant surface pressure and area, respectively. The first compression-expansion cycle of the monolayer is not reversible and the second pi-A compression isotherm deviates to larger molecular areas relative to the first one. At a microscopic level this hysteresis may be assigned to an irreversible hydration of the ammonium groups of DODAB. The morphology and reflectivity of DODAB monolayers during compression and expansion on the monolayer depend on the monolayer history. Bright domains randomly dispersed were observed during compression before collapse. Surprisingly, this random distribution of domains changes into a fractal-like structure during the monolayer expansion in a narrow range of surface pressures. This morphology does not form when the monolayer is previously compressed above the collapse surface pressure. 2D foam-like structure is often observed when the film is expanded at maximum area. Relaxation phenomena in DODAB monolayers are attributed to monolayer reorganization and nucleation of liquid-condensed domains from the liquid-expanded phase. These time-dependent processes are irreversible.
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Rodríguez Patino JM, Molina Ortiz SE, Carrera Sánchez C, Rodríguez Niño MR, Añón MC. Dynamic properties of soy globulin adsorbed films at the air-water interface. J Colloid Interface Sci 2003; 268:50-7. [PMID: 14611771 DOI: 10.1016/s0021-9797(03)00642-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper we present surface dilatational properties of soy globulins (beta-conglycinin, glycinin, and reduced glycinin with 10 mM of dithiothreitol (DTT)) adsorbed onto the air-water interface, as a function of adsorption time. The experiments were performed at constant temperature (20 degrees C), pH (8.0), and ionic strength (0.05 M). The surface rheological parameters were measured as a function of protein concentration (ranging from 1 to 1x10(-3)% wt/wt). We found that the surface dilatational modulus, E, increases, and the phase angle, phi, decreases with time, theta, which may be associated with protein adsorption. These phenomena have been related to protein adsorption, unfolding, and/or protein-protein interactions (at long-term adsorption) as a function of protein concentration in solution. From a rheological point of view, the surface viscoelastic characteristics of soy globulin films adsorbed at the air-water interface are practically elastic. The main conclusion is that the dilatational properties of the adsorbed films depend on the molecular structure of the protein.
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Affiliation(s)
- Juan M Rodríguez Patino
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, c. Prof. García González, s/núm. 41012, Sevilla, Spain.
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Douillard R, Daoud M, Aguié-Béghin V. Polymer thermodynamics of adsorbed protein layers. Curr Opin Colloid Interface Sci 2003. [DOI: 10.1016/s1359-0294(03)00097-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Structural characterization and surface activity of spread and adsorbed soy globulin films at equilibrium. Colloids Surf B Biointerfaces 2003. [DOI: 10.1016/s0927-7765(03)00146-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Rodríguez Patino JM, Molina Ortiz SE, Sánchez CC, Rodríguez Niño MR, Añon MC. Behavior of Soy Globulin Films at the Air−Water Interface. Structural and Dilatational Properties of Spread Films. Ind Eng Chem Res 2003. [DOI: 10.1021/ie030140s] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Juan M. Rodríguez Patino
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, c/. Prof. García González, s/núm. 41012 Sevilla, Spain, and Centro de Investigación y Desarrollo en Criotecnología de Alimentos (CIDCA), Facultad de Ciencias Exactas, Universidad Nacional de la Plata, Calle 47 y 116, 1900 La Plata, Argentina
| | - Sara E. Molina Ortiz
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, c/. Prof. García González, s/núm. 41012 Sevilla, Spain, and Centro de Investigación y Desarrollo en Criotecnología de Alimentos (CIDCA), Facultad de Ciencias Exactas, Universidad Nacional de la Plata, Calle 47 y 116, 1900 La Plata, Argentina
| | - Cecilio Carrera Sánchez
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, c/. Prof. García González, s/núm. 41012 Sevilla, Spain, and Centro de Investigación y Desarrollo en Criotecnología de Alimentos (CIDCA), Facultad de Ciencias Exactas, Universidad Nacional de la Plata, Calle 47 y 116, 1900 La Plata, Argentina
| | - Ma. Rosario Rodríguez Niño
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, c/. Prof. García González, s/núm. 41012 Sevilla, Spain, and Centro de Investigación y Desarrollo en Criotecnología de Alimentos (CIDCA), Facultad de Ciencias Exactas, Universidad Nacional de la Plata, Calle 47 y 116, 1900 La Plata, Argentina
| | - Ma. Cristina Añon
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, c/. Prof. García González, s/núm. 41012 Sevilla, Spain, and Centro de Investigación y Desarrollo en Criotecnología de Alimentos (CIDCA), Facultad de Ciencias Exactas, Universidad Nacional de la Plata, Calle 47 y 116, 1900 La Plata, Argentina
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39
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Adsorption kinetics of BSA at air–sugar solution interfaces as affected by sugar type and concentration. Food Res Int 2003. [DOI: 10.1016/s0963-9969(03)00004-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Rodríguez Patino JM, Rodríguez Niño MR, Sánchez CC. Relaxation Phenomena in Whey Protein Isolate and Monoglyceride Mixed Films at the Air−Water Interface. Ind Eng Chem Res 2002. [DOI: 10.1021/ie010868d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Juan M. Rodríguez Patino
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/Prof. García González, s/núm, 41012 Seville, Spain
| | - Ma. Rosario Rodríguez Niño
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/Prof. García González, s/núm, 41012 Seville, Spain
| | - Cecilio Carrera Sánchez
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/Prof. García González, s/núm, 41012 Seville, Spain
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Rodríguez Patino JM, Rodríguez Niño MR, Sánchez CC. Static and Dynamic Properties of a Whey Protein Isolate and Monoglyceride Mixed Films at the Air−Water Interface. Ind Eng Chem Res 2002. [DOI: 10.1021/ie010882q] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Juan M. Rodríguez Patino
- Departamento de Ingeniería Química, Facultad de Química. Universidad de Sevilla, C/Prof. García González, s/núm. 41012-Seville. Spain
| | - M. Rosario Rodríguez Niño
- Departamento de Ingeniería Química, Facultad de Química. Universidad de Sevilla, C/Prof. García González, s/núm. 41012-Seville. Spain
| | - Cecilio Carrera Sánchez
- Departamento de Ingeniería Química, Facultad de Química. Universidad de Sevilla, C/Prof. García González, s/núm. 41012-Seville. Spain
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Rodríguez Niño MR, Rodríguez Patino JM. Effect of the Aqueous Phase Composition on the Adsorption of Bovine Serum Albumin to the Air−Water Interface. Ind Eng Chem Res 2002. [DOI: 10.1021/ie010770z] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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43
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Structural and Dynamic Properties of Milk Proteins Spread at the Air–Water Interface. J Colloid Interface Sci 2001. [DOI: 10.1006/jcis.2001.7756] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Rodríguez Patino JM, Rodríguez Niño MR, Carrera Sánchez C, Cejudo Fernández M. The Effect of pH on Monoglyceride-Caseinate Mixed Monolayers at the Air-Water Interface. J Colloid Interface Sci 2001; 240:113-126. [PMID: 11446793 DOI: 10.1006/jcis.2001.7567] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The surface pressure (pi) area (A) isotherms and Brewster angle microscopy (BAM) of monoglyceride-caseinate mixed films spread on buffered water at pH 5 and 7 and at 20 degrees C were determined as a function of the mass fraction (X) of monoglyceride (monopalmitin or monoolein) in the mixture. The structural characteristics, miscibility, and morphology of monoglyceride-caseinate mixed films are very dependent on surface pressure and monolayer composition. The monolayer structure was more expanded as the pH and the monoglyceride concentration in the mixture were increased. From the concentration and surface pressure dependence on excess area, free energy, and collapse pressure, it was deduced that, at a macroscopic level, monoglyceride (either monopalmitin or monoolein) and caseinate form a practically immiscible monolayer at the air-water interface. The BAM images and the evolution with the surface pressure of the relative reflectivity of BAM images give complementary information on the interactions and structural characteristics of monoglyceride-caseinate mixed monolayers, which at a microscopic level corroborated in part the conclusions derived from the pi-A isotherm at a macroscopic level. Over the overall range of existence of the mixed film the monolayer presents some heterogeneity due to the fact that domains of monoglyceride (especially of monopalmitin) and spots of collapsed caseinate residues are present during the monolayer compression-expansion cycle, giving relative intensity peaks with high relative film thickness. At higher pi, after the caseinate collapse, characteristic squeezing-out phenomenon was observed. At the monoglyceride monolayer collapse the mixed film is practically dominated by the presence of monoglyceride. The prevalence of monoglyceride in the interface increases with the amount of monoglyceride in the mixture and at higher pi. However, some degree of interactions exists between monoglyceride and caseinate in the mixed film and these interactions are more pronounced as the monolayer is compressed at the highest surface pressures. Copyright 2001 Academic Press.
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Affiliation(s)
- Juan M. Rodríguez Patino
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, c/Profesor García González, s/núm., Seville, 41012, Spain
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Rodríguez Patino JM, Rodríguez Niño MR, Carrera Sánchez C, Navarro García JM, Rodríguez Mateo GR, Cejudo Fernández M. The effect of temperature on food emulsifiers at fluid–fluid interfaces. Colloids Surf B Biointerfaces 2001; 21:87-99. [PMID: 11377938 DOI: 10.1016/s0927-7765(01)00187-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Heat-induced interfacial aggregation of a whey protein isolate (WPI) with a high content of beta-lactoglobulin (>92%), previously adsorbed at the oil-water interface, was studied by means of interfacial dynamic characteristics performed in an automatic drop tensiometer. Protein concentration in aqueous bulk phase ranging between 1x10(-1) and 1x10(-5) % wt/wt was studied as a variable. The experiments were carried out at temperatures ranging from 20-80 degrees C with different thermal regimes. During the heating period, competition exists between the effect of temperature on the film fluidity and the increase in mechanical properties associated with the interfacial gelation process. Interfacial crystallisation of food polar lipids (monopalmitin, monoolein, and monolaurin) previously adsorbed at the oil-water interface, was studied by interfacial dynamic characteristics (interfacial tension and surface dilational properties). The temperature, ranging between 40 and 2 degrees C, and the lipid concentration in aqueous oil phase, ranging between 1x10(-2) and 1x10(-4) % wt/wt, were studied as variables. Significant changes in interfacial dynamic characteristics associated with interfacial lipid crystallisation were observed as a function of lipid concentration in the bulk phase. Interfacial crystallisation of food polar lipids (monopalmitin, monoolein, and monolaurin) at the air-water interface, was studied by pi-A isotherms performed in a Langmuir trough coupled with Brewster angle microscopy (BAM). A condensation in monoglyceride monolayers towards lower molecular area was observed as the temperature decreased. This effect was attributed to lipid crystallisation at lower temperatures. BAM images corroborated the effect of temperature on the monolayer structure, as a function of the monoglyceride type.
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Affiliation(s)
- J M. Rodríguez Patino
- Departamento de Ingeniería Químíca, Universidad de Sevilla, C/. Professor García González, s/Núm, 41012-Sevilla, Sevilla, Spain
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46
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Cicuta P, Hopkinson I. Studies of a weak polyampholyte at the air–buffer interface: The effect of varyingpH and ionic strength. J Chem Phys 2001. [DOI: 10.1063/1.1365401] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Dickinson E. Milk protein interfacial layers and the relationship to emulsion stability and rheology. Colloids Surf B Biointerfaces 2001; 20:197-210. [PMID: 11172975 DOI: 10.1016/s0927-7765(00)00204-6] [Citation(s) in RCA: 395] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The properties of milk protein-stabilised, oil-in-water emulsions are determined by the structure and surface rheology of the adsorbed layer at the oil-water interface. Analysis of the segment density profiles normal to the surface show differences in the structure between adsorbed layers of disordered casein and globular whey protein. Systematic studies of stability and rheology of model oil-in-water emulsion systems made with milk proteins as sole emulsifiers give insight into the relation between adsorbed layer properties and bulk emulsion stability. Of particular importance are effects of pH, temperature, calcium ions and protein content. Colloidal interactions between adsorbed layers on different surfaces can be inferred from an analysis of dynamic collisions of protein-coated emulsion droplets in shear flow using the colloidal particle scattering technique. The role of competitive adsorption on emulsion properties can be derived from experiments on systems containing mixtures of milk proteins and small-molecule surfactants. Shear-induced destabilisation is especially influenced by the presence of fat crystals in the emulsion droplets. Aggregated gel network properties are dependent on the balance of weak and strong interparticle interactions. In heat-set whey protein emulsion gels, the rheological behaviour is especially sensitive to surfactant type and concentration. Rearrangements of transient caseinate-based emulsion gels can have a profound influence on the quiesent stability behaviour. Computer simulation provides a general link between particle interactions, microstructure and rheological properties.
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Affiliation(s)
- E Dickinson
- Procter Department of Food Science, University of Leeds, LS2 9JT, Leeds, UK
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48
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Abstract
Adapting a hard hexagon model to describing protein adsorption, we show by using Monte Carlo simulations that the ordering of adsorbed proteins may strongly depend on the relative location of the hydrophilic and hydrophobic patches on their surface. Specifically, proteins may form dimers, trimers, small rings, and zig-zag or straight chains or islands consisting of such fragments.
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Affiliation(s)
- V P Zhdanov
- Department of Applied Physics, Chalmers University of Technology, Göteborg, Sweden.
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49
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Rodrı́guez Patino JM, Rodrı́guez Niño M. Interfacial characteristics of food emulsifiers (proteins and lipids) at the air-water interface. Colloids Surf B Biointerfaces 1999. [DOI: 10.1016/s0927-7757(99)00012-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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50
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Rodrı́guez Patino J, Sánchez C, Rodrı́guez Niño M. Structural and morphological characteristics of β-casein monolayers at the air–water interface. Food Hydrocoll 1999. [DOI: 10.1016/s0268-005x(99)00025-9] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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