References of "Razafindralambo, Hary"
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See detailAdvances in Physical Chemistry Tools for Probiotic Characterization
Razafindralambo, Hary ULiege

in Razafindralambo, Hary (Ed.) Trends in Probiotic Applications (2018)

Probiotics are microorganisms that have existed for many centuries. However, they are being recognized, only nowadays, as beneficial microorganisms for human, animal and plant species by a wide population ... [more ▼]

Probiotics are microorganisms that have existed for many centuries. However, they are being recognized, only nowadays, as beneficial microorganisms for human, animal and plant species by a wide population community. Both scientists and industries are trying to discover further while better understanding their roles, behaviors, mechanisms and functionalities for generating high-quality profitable products. Several strategies are available for the probiotic investigation in terms of identification, quality, quantity, and mechanism of action. Most of them are based on biological, biochemical and/or physiological methods. Nevertheless, physical chemical approaches appear very attractive, but less exploited for characterizing and controlling microorganism qualities and performances. This chapter is intended to fill the gap by overviewing the advances in physical chemical methods for probiotic characteriza-tion. Its content deals successively with spectroscopy, microscopy, surface analysis, and calorimetry techniques applied to probiotic-based products. [less ▲]

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See detailProbiotics from Food and Non-Food Sources
Rabetafika, Holy; Razafindralambo, Aurélie; Razafindralambo, Hary ULiege

in Razafindralambo, Hary (Ed.) Trends in Probiotic Applications (2018)

Nowadays, there is a growing interest in probiotics owing to their high potential therapeutic and preventive health effects. These beneficial microorganisms are natural, relatively safe, and can be ... [more ▼]

Nowadays, there is a growing interest in probiotics owing to their high potential therapeutic and preventive health effects. These beneficial microorganisms are natural, relatively safe, and can be incorporated in food and non-food products. Although a large variety of probiotics have already been discovered, well-identified, and approved, it is always important to update, classify, and determine all their potential sources, currently available. In this chapter, we attempt to report all existing probiotic strains from both food and non-food sources, as well as their positive effects on health. Microorganisms unrecognized yet as probiotics while having potential health benefits are also listed. Probiotics from food sources may contain various species that are found in fermented foods, including dairy products, fruit, vegetables, fish, and meat. Probiotics also occur in non-food products, especially in the human and animal microbiota, air environment, soil and sea. [less ▲]

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See detailTRENDS in PROBIOTIC APPLICATIONS
Razafindralambo, Hary ULiege

Book published by Studium Press LLC (2018)

This book proposes current and relevant information on the potentiality and opportunity that probiotics offer as natural, safe, and cost-effective solutions to improve human life, and solve the most ... [more ▼]

This book proposes current and relevant information on the potentiality and opportunity that probiotics offer as natural, safe, and cost-effective solutions to improve human life, and solve the most devastator diseases of the 21st century. As existing microorganisms since many centuries, we are only trying to discover and better understand their roles, behaviors, mechanisms, and functionalities, which are beneficial for human, animal and plant species. Their use will undoubtedly be multiple and inevitable in the future through the extension of in vitro and in vivo tests, as well as clinical trials. Even though a large number of books have been written and published on probiotics and their potential functionalities in different aspects and specific areas, only a few ones collect and provide both thorough and pertinent information on the real possibilities of their use as natural solutions for food and non-food applications throughout the World. The present contribution aims at filling the gap in this context. Three main parts are included: (1) An overview of the international regulation and technological aspects of probiotic-containing product categories, the strain efficiency and safety assessments, and the principal probiotic strains and their metabolites; (2) An update and classification of the natural probiotic sources and their main health benefits, and the advances in physical chemistry tools for probiotic characterization; (3) A review of uncommon while prominent selected probiotic applications in food and non-food areas. The chapters result from the contribution of Authors from four continents, including Europe (IT, BE, SP), America (US), Asia (MY, PK), and Africa (BJ, CI, BF), who have expertise in their specific fields. The book targets all interested people searching new, natural, efficient, and sustainable solutions for food quality and health care. These concern various professionals, from food technologists and industrial microbiologists to health and nutrition practitioners, through government regulatory agents. [less ▲]

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See detailPhysico-chemical Approach for Characterising Probiotics: example of High Concentrated Multistrain-Based Formulation
Razafindralambo, Hary ULiege; Delvigne, Frank ULiege; Blecker, Christophe ULiege

Poster (2017, October 09)

Probiotics are receiving today unprecedented growing interests in Europe, Asia, and in the rest of the world. Their applications are not only limited to food and health sectors, but cover also agriculture ... [more ▼]

Probiotics are receiving today unprecedented growing interests in Europe, Asia, and in the rest of the world. Their applications are not only limited to food and health sectors, but cover also agriculture and aquaculture areas. The quality of probiotic products depends on many factors such as, the properties of each individual strain and its proportion in mixed products, the viable probiotic dose, and other selective ingredients like prebiotics and protectant agents incorporated into the formulation. Several strategies are employed for ensuring high product qualities, which can be controlled by different methods and techniques. To date, the physico-chemical approach for characterizing and controlling probiotic qualities and performances appears very attractive, but less exploited. It particularly consists in characterizing probiotic products in terms of thermal, surface and colloidal properties, which could be correlated to probiotic viability and functionalities. In this communication, we report the efficiency of such an approach when applied to a high concentrated multistrain-based formulation which has been shown a metabolic variability impacting on the inflammatory response, depending on the production site. [less ▲]

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See detailFrom Theory to Practice of Dynamic and Equilibrium Interfacial and Colloidal Properties
Razafindralambo, Hary ULiege

Scientific conference (2017)

Interfaces are the boundary limits of at least two immiscible phases that include gas, liquid and solid, and are characterized by the interfacial free energy. Understanding their fundamental property ... [more ▼]

Interfaces are the boundary limits of at least two immiscible phases that include gas, liquid and solid, and are characterized by the interfacial free energy. Understanding their fundamental property modifications in deep manner is of great importance, regarding to scientific and application viewpoints. That allows us to control the formation and stabilization of colloidal systems, which consist in producing homogeneous dispersions from, at least, two initially immiscible phases. In this communication, the dynamic and equilibrium aspects of fluid and solid surfaces were theoretically reminded, and some applications related to surface-active biocompounds with short chain derivatives (hydrosolubles) by dynamic adsorption (Gibbs approach), and with long chain derivatives (liposolubles) through the spreading and compressed monolayer (Langmuir approach) were shown, respectively. A few examples of the most relevant relationships between fundamental properties and colloidal formation and stability consequences were presented. [less ▲]

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See detailP-301 High Concentration Multistrain Probiotic Produced at Different Manufacturing Sites: Comparative Analysis.
Lombardi, Francesca; La Torre, Cristina; Giusti, Ilaria et al

in Inflammatory Bowel Diseases (2017), 23

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See detailNutrition-Based therapeutic approaches for solving autistic digestive troubles
Razafindralambo, Hary ULiege; Rabetafika, H.; Razafindralambo, A.

in Adv Food Technol Nutr Sci Open J (2016), 2(3), 88-95

Diagnosing and treating additional health problems in autistic children or adults, beyond their own autism troubles, is always a challenge under first of parent responsibility. This paper reports on the ... [more ▼]

Diagnosing and treating additional health problems in autistic children or adults, beyond their own autism troubles, is always a challenge under first of parent responsibility. This paper reports on the success of nutrition-based therapeutic approaches for improving the health and solving digestive troubles of a communicating-impaired and initially overweight patient. Symptoms include frequent burping, and diagnoses revealed hiatal hernia and stomach ulcers. Two different diet plans have been successively applied over one year. Each half-year diet impact has been home-monitored by measuring the body-mass data and index. Details on nutrition, supplement and drug intakes, as well as any observations were daily recorded. The first halfyear diet was based on gastroesophageal reflux preventing recommendations, whereas the 2nd diet plan was elaborated from the metabolic typing and gluten intolerance information. Normal body mass index (BMI) values (20-25) were reached during the 1st phase, which was marked by an increase in the intake of food supplement and a reduction in the frequency of drug intakes, especially from the 4th month. After one-year of nutrition-based therapy, the patient health has been generally improved, and the hiatal hernia and ulcer problems have disappeared. A database containing all information recorded throughout the diet plans was created. During the patient body-mass loss, the muscle part increased whereas the fat part dropped. Such fat mass loss observed over the 1st 4 months was possibly correlated to the intake frequency diminution of proton pump inhibitor, acting against the gastric acid secretion. During last 6-months of strict nutrition therapy, the body mass remained stable. [less ▲]

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See detailFundamental property and functional aptitude relationships in emulsion and foam applications of amphiphilic compounds
Razafindralambo, Hary ULiege

Conference (2013, April 11)

Amphiphilic compounds are issued of a combination of two opposite entities, covalently assemblied within a single structure. By the diversity of the origin, class, number of monomer and substitute, size ... [more ▼]

Amphiphilic compounds are issued of a combination of two opposite entities, covalently assemblied within a single structure. By the diversity of the origin, class, number of monomer and substitute, size, linker or spacer, stereochemistry of the molecular entities, their chemical structure may be very different but also close each other. However, they may fulfill the same role in reducing surface and interfacial free energy in dynamic or static ways, ensuring especially the formation of dispersed systems like emulsion and foam. If the relationships between the structural variable and fundamental properties are strictly chemical residue dependent, those between fundamental and functional aptitudes are not necessarily. In this case, general and universal rules may exist, whatever the kind of amphiphilic compounds. In order to achieve a rational design for any expected functionality, we attempt to find out some predictive and conception rules from a lot of screening data of fundamental and functional properties. In this communication, some correlations between fundamental data related to surface and interfacial properties, measured by molecule adsorption or spreading under dynamic or static mode, in compression or dilation of adsorbed or spread film, and emulsifying and foaming performances of various bio-based surfactants will be presented. [less ▲]

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See detailPhoton correlation spectroscopy for molecular self-assembly investigations
Razafindralambo, Hary ULiege

Conference (2013, April 11)

The molecular self-assembly performance is among the most important functionalities of amphiphilic compounds in colloidal system areas. This aptitude is required in numerous applications, depending on ... [more ▼]

The molecular self-assembly performance is among the most important functionalities of amphiphilic compounds in colloidal system areas. This aptitude is required in numerous applications, depending on solubilization, hydrotropy, rheology, separation, loading and delivery, encountered in biological and industrial processes. The main physicochemical parameter predicting the capacity of amphiphiles to self-assembly in bulk liquid, aqueous (normal micelles) or non-aqueous phase (reverse micelles), is the pair critical micelle concentration (CMC) and temperature (CMT). A variety of methods based on surface tension, spectral changes, and electrical conductivity are commonly used for determining the value of CMC. The choice usually depends on the ionic or non-ionic nature of the amphiphilic compounds. In this communication, a standard Photon Correlation Spectroscopy (PCS), also known Light Scattering-based technique for CMC determination will be theoretically and practically described in details. Its particular interest for measuring the performance of non-ionic and very high hydrophobic tail, mono or disubstituted carbohydrate-based compounds, from C16 alkyl chain, will be demonstrated. Such a method is advantageous regarding the time, amount, and resolution required, but also for additional information on micelle size, aggregate number, and stability it may provide, compared to surface tension and electrical conductivity-based measurements. [less ▲]

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See detailAmphiphilic structure-surface property relationships of monosaccharide-based surfactants
Razafindralambo, Hary ULiege; Nicks, Francois ULiege; Richard, Gaetan ULiege et al

Poster (2013, April 08)

A set of monosaccharide-based renewable surfactants has been prepared, structurally checked, and systematically screened for different activities and functionalities. These compounds vary in the polar ... [more ▼]

A set of monosaccharide-based renewable surfactants has been prepared, structurally checked, and systematically screened for different activities and functionalities. These compounds vary in the polar head group, linker, and hydrophobic tail. Beyond the goal to find out the most potential valuable surfactants for each measurement, relationships between chemical structure, basic properties, and functionalities have been examined by comparing compounds differing in a single structural variable. In this paper, we show and explain the impact of the anomeric alpha or bêta, neutral or acid sugar derivatives, equatorial or axial position of hydroxyl group, alkyl chain substitute attachment position, number, and length on surface properties of sugar-based surfactants. [less ▲]

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See detail(Bio)-amphiphilic compounds as biohybrid materials: the case of peptidolipids and glycolipids
Razafindralambo, Hary ULiege

Conference (2013, March)

(Bio)-hybrid compounds are constituted by at least two distinct classes of component covalently linked within the same structure. Amphiphilic compounds of peptide- and oligosaccharide-lipid groups are ... [more ▼]

(Bio)-hybrid compounds are constituted by at least two distinct classes of component covalently linked within the same structure. Amphiphilic compounds of peptide- and oligosaccharide-lipid groups are among representatives bio-hybrid molecules with increasing interests since each of them contains two entities belonging to important categories of biological molecules like proteins, carbohydrates, and lipids. The strength of such compounds is by far their possibility to exhibit multifunctional properties and activities, specifically developed by each of these three biomolecule classes. In addition, their intermediate size with regard to small and large molecular structures may present certain undeniably advantages, for instance, a lower diffusivity and a greater solubility in aqueous solution compared to small and polymeric surfactants, respectively. In this paper, the case of peptide and carbohydrate-based surfactants containing a linear series of alkyl fats will be presented and discussed regarding to interfacial properties, colloidal stabilities, and biological activities with the perspective of getting more efficient hybrid compounds by rational design approaches. [less ▲]

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See detailInvestigation of Structure-Fundamental/Functional Property Relationships of (Bio)-surfactants for a Rational Design of their Preparation and Use in Food and Non-food applications
Razafindralambo, Hary ULiege

Conference (2012, May 01)

(Bio)-surfactants are among the most versatile compounds in our planet, either in nature or in biological systems, as well as in manufactured products. Increasing knowledge on the relationships between ... [more ▼]

(Bio)-surfactants are among the most versatile compounds in our planet, either in nature or in biological systems, as well as in manufactured products. Increasing knowledge on the relationships between their structure, fundamental properties, and functionalities in simple, and thereafter in more complicated models, are therefore the key factor on their rational preparation and use for any applications. In the present communication, the effect of different structural entities of (bio)surfactants, especially Carbohydrate-based amphiphilic compounds, including monomeric, oligomeric, and polymeric surfactants, on their interfacial properties at short time (under dynamic conditions) and long time (at the equibrium), and the impact of such fundamental properties through physico-chemical parameters on the formation and stability of colloidal systems (micelles, foams, emulsions) will be presented. Some perspectives in their applications will be discussed. [less ▲]

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See detailAdsorption kinetics of total proteose peptone fractions at the air-water and n-dodecane-water interface
Karamoko, Gaoussou ULiege; Razafindralambo, Hary ULiege; Danthine, Sabine ULiege et al

Poster (2012, March 26)

Surface properties of whey proteins are essential in applications requiring oil emulsification in an aqueous phase, or foam structure formation [1]. The adsorption at interfaces constitutes then an ... [more ▼]

Surface properties of whey proteins are essential in applications requiring oil emulsification in an aqueous phase, or foam structure formation [1]. The adsorption at interfaces constitutes then an approach of the physico-chemical mechanisms of foaming and emulsifying properties. Proteose-peptone is the minor fraction of whey's protein, thermoresistant and acid-soluble protein fraction extracted from milk [2], and known for its interesting surface properties [3]. In this study, the TPP fractions were extracted from skimmed milk UHT (milk TPP) and whey protein concentrate (WPC TPP). Their adsorption kinetics at the air-water and n-dodecane-water interfaces was investigated by the drop volume tensiometer method. Protein solutions of 1% (w/v) were <br />characterized under dynamic condition at various pH (4.0; native pH 4.67- 4.70 and 7.0). Milk TPP showed the lowest values as well as a faster reduction in surface tension at both considered interfaces. Therefore, TPP were found to e effective as surfactants. These results let us to presage good emulsifying and foaming properties of milk TPP compared to WPC TPP. The considerable influence of pH and extraction source on proteose-peptone's interfacial property have been highlighted. [less ▲]

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See detailImpact of the alkyl chain carbon atom number of uronic acid-derivative surfactants on interfacial and colloidal systems
Razafindralambo, Hary ULiege; Richard, Gaetan ULiege; Laurent, Pascal ULiege et al

Poster (2012, March 26)

Uronic acid-derivative surfactants represent today an attractive group of Carbohydrate-based amphiphilic compounds for both fundamental and practical reasons [1,2]. In the continuity of our screening of ... [more ▼]

Uronic acid-derivative surfactants represent today an attractive group of Carbohydrate-based amphiphilic compounds for both fundamental and practical reasons [1,2]. In the continuity of our screening of their basic properties, and the approach in establishing relationships between their structure and properties [3,4], the impact of the alkyl chain carbon atom number on interfacial and colloidal systems has been systematically investigated. In this communication, the effect of odd-even number of carbon atom from C11 to C18, and the particular behavior of long chain derivatives on interfacial properties, as well as their impact on the formation and stability of colloidal systems, are presented. Experimental approaches have been conducted by investigating their properties and behaviors at gas-liquid and liquid-liquid under dynamic, equilibrium, and oscillatory interfacial conditions. Results are completed by and discussed with single molecule models established by theoretical approaches. [1] Razafindralambo, H.;Blecker, C.; Paquot, M., Screening of Basic Properties of Amphiphilic Molecular Structures for Colloidal System Formation and Stability. In Amphiphiles: Molecular Assembly and Applications, American Chemical Society: 2011; Vol. 1070, pp 53-66. [2] Laurent, P.; Razafindralambo, H.; Wathelet, B.; Blecker, C.; Wathelet, J.; Paquot, M., Synthesis and Surface-Active Properties of Uronic Amide Derivatives, Surfactants from Renewable Organic Raw Materials. J. Surfactants Deterg. 2011, 14, 51-63. [3] Razafindralambo, H.; Richel, A.; Wathelet, B.; Blecker, C.; Wathelet, J.; Brasseur, R.; Lins, L.; Miñones, J.; Paquot, M., Monolayer properties of uronic acid bicatenary derivatives at the air-water interface: effect of hydroxyl group stereochemistry evidenced by experimental and computational approaches. Physical chemistry chemical physics: PCCP 2011, 13 15291-15298. [4] Razafindralambo, H.; Blecker, C.; Mezdour, S.; Deroanne, C.; Crowet, J.; Brasseur,R.; Lins, L.; Paquot, M., Impacts of the Carbonyl Group Location of Ester Bond on Interfacial Properties of Sugar-Based Surfactants: Experimental and Computational Evidences. The journal of physical chemistry. B 2009, 113, 8872-8877. [less ▲]

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See detailRelationships between structure-interfacial-functional properties: The rheology at interfaces from small to polymeric carbohydrate-based surfactants
Razafindralambo, Hary ULiege

Conference (2012, March 25)

Amphiphilc molecules are one of the most important compounds in our planet owing to their fundamental role as catalysts of interfacial free energy in nature, biological systems, and manufacturated ... [more ▼]

Amphiphilc molecules are one of the most important compounds in our planet owing to their fundamental role as catalysts of interfacial free energy in nature, biological systems, and manufacturated products [1]. Their chemical structure and configuration, which governs their properties and activities, may be classified in small, intermediate, and large sizes. To better understand the effect of such a parameter, the behaviors of various carbohydrate-based surfactants, from small to polymeric molecular structures at the air-water interface, and in bulk liquid for their ability to form and stabilize related colloidal systems like micelles and foams have been investigated. In particular, rheological properties including elasticity and viscosity components at the air-water interface have been determined by oscillatiory mode under different oscillation frequency and surfactant concentration conditions using a pending drop tensiometer system. Their micellar and foaming properties have been characterized and evaluated in terms of CMC-micelle size and formation-stability, respectively. Reference: [1] Razafindralambo, H.; Blecker, C.; Paquot, M., Screening of Basic Properties of Amphiphilic Molecular Structures for Colloidal System Formation and Stability. In Amphiphiles: Molecular Assembly and Applications, Ed. R. Nagarajan, American Chemical Society: 2011;. Vol. 1070, pp 53-66. [less ▲]

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See detailCarbohydrate-based surfactants: structure-activity relationships
Razafindralambo, Hary ULiege; Blecker, Christophe ULiege; Paquot, Michel ULiege

in Nawaz, Zeeshan; Naveed, Shahid (Eds.) Advances in Chemical Engineering (2012)

The aim of the present contribution is: (1) to review CBS in terms of structural classification based on their molecular size (mono-, oligo-, polymeric surfactants), geometry (standard, bipolar or ... [more ▼]

The aim of the present contribution is: (1) to review CBS in terms of structural classification based on their molecular size (mono-, oligo-, polymeric surfactants), geometry (standard, bipolar or bolaform, and gemini surfactants), and the nature of the polar headgroup (charged or not, cyclic or not), the apolar tail (number and length of alkyl chain), and the linker (amide, ester, ...) and/or the spacer; (2) to present systematically results on structure- activity relationships of uronic acid derivatives (UADs), a particular class of carbohydrate-based surfactants. These concern the impact of each structural entity including the polar headgroup (stereochemistry), apolar tail (chain length, number, and unsaturation), and linkage/spacer, on the performance of UADs to change surface properties, and possibly, to form and stabilize colloidal systems. [less ▲]

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See detailLiquid Crystalline Phases Induced by the Hydroxyl Group Stereochemistry of Amphiphilic Carbohydrate Bicatenary Derivatives
Razafindralambo, Hary ULiege; Richel, Aurore ULiege; Paquot, Michel ULiege et al

in Journal of Physical Chemistry B (2012), 116(13), 3998-4005

Liquid-crystals (LC) may exist in different phases depending upon the orientational and positional orders of molecules in the material. Here, we demonstrate that the class of LC state induced by ... [more ▼]

Liquid-crystals (LC) may exist in different phases depending upon the orientational and positional orders of molecules in the material. Here, we demonstrate that the class of LC state induced by amphiphilic carbohydrate bicatenary derivatives is strictly a hydroxyl group stereochemistry-dependent. This statement results from the experimental and theoretical investigations of surface film (2D) and bulk solid (3D) thermal behavior of synthetic stereoisomers n-tetradecyl (-D-n-tetradecyl) galacto- and gluco-pyranosiduronate, with an axial (GalA-C14/14) or equatorial (GlcA-C14/14) hydroxyl group at the fourth carbon, respectively. Surface pressure-area isotherms (283 K to 310 K), differential scanning calorimetry thermograms (223 K to 573 K), and polarized optical textures (298-363 K) reveal that GlcA-C14/14 organizes as a smectic LC-like phase (positional or lateral order) whereas the analogous stereoisomeric GalA-C14/14 behaves as a nematic LC-like phase (orientational order). Thermodynamic investigations and molecular dynamics models computed under similar temperature conditions provide consistent data with physical properties resulting from experimental approaches. [less ▲]

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See detailBINDING INTERACTIONS OF URONIC ACID DERIVATIVES TO LIPID VESICLES INVESTIGATED BY ISOTHERMAL TITRATION CALORIMETRY
Razafindralambo, Hary ULiege; Laurent, Pascal ULiege; Wathelet, Jean-Paul ULiege et al

Poster (2011, November 12)

Uronic acid derivatives (UAD) constitute a particular class of carbohydrate-based small compounds, which are receiving growing interests today for many reasons. Beyond their excellent environmental ... [more ▼]

Uronic acid derivatives (UAD) constitute a particular class of carbohydrate-based small compounds, which are receiving growing interests today for many reasons. Beyond their excellent environmental compatibility, their potentiality mainly arises from the large abundance of their precursors from renewable resources, and the quasi-unlimited availability of their molecular structure and geometry [1]. Such a structural diversity allows them to be a typical compound class for the structure-activity relationship investigation using simplest models. This approach is very important for predicting their functionalities and activities. Among others, searching specific and potent biological activities against target molecules, cells, and micro-organisms is a big challenge today. In this context, binding interactions of three UAD having different hydrophobic residues (allyl, benzyl, and cyclohexyl) to 1-palmitoyl-2-oleyl-sn-glycerol-3-phosphatidylcholine (POPC) vesicles have been investigated using Isothermal Titration Calorimetry (ITC) technique [2]. The binding affinity (Ka) to the membrane model at 25°C has been determined and compared for the three compounds. Based on thermograms resulting from UAD aqueous solution titration experiments, with and without POPC vesicles, it clearly appears that both derivatives with a cyclic residue interact stronger with the lipid membrane model than their linear derivative counter-part, which exhibits almost no interaction. Moreover, the derivative compound with a cyclohexyl residue saturates faster POPC vesicles than that with a benzyl residue. We conclude that: (a) UAD having a cyclic hydrophobic residue, either saturated or unsaturated, bind more easily to the lipid membrane model than a linear one ending with a double bond; (b) the greater the number of hydrogen in the UAD residue chemical structure (saturated bonds), the stronger their binding affinity to POPC vesicles, suggesting the importance of H-bonding to such a lipid membrane model. The Ka mean value of the best tested UAD, i.e. with a cyclohexyl residue, is about 5.103 M-1. [1] Razafindralambo, H.; Blecker, C; and M. Paquot., Screening of basic properties of amphiphilic molecular the structures for colloidal system formation and stability: the case of carbohydrate-based surfactants in: Amphiphiles: Molecular Assembly and Applilcations, ed. R. Nagarajan, ACS, Washignton, 2011, (In press). [2] Razafindralambo, H.; Dufour, S.; Paquot, M.; Deleu, M., Thermodynamic studies of the binding interactions of surfactin analogues to lipid vesicles: application of isothermal titration calorimetry. J. Therm. Anal. Calorim., 2009, 9 (3), 817-821. Acknowledgment: This work was supported by Belgian Walloon Region with DG06 research project of excellence (TECHNOSE). [less ▲]

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See detailScreening of Basic Properties of Amphiphilic Molecular Structures for Colloidal System Formation and Stability. The Case of Carbohydrate-Based Surfactants
Razafindralambo, Hary ULiege; Blecker, Christophe ULiege; Paquot, Michel ULiege

in In Amphiphiles: Molecular Assembly and Applications; Nagarajan, R. (2011)

Colloidal systems are bubbles, droplets, or/and particles dispersed in a continuous media, which are encountered in nature, biological system, and manufactured products. As site of interfaces between at ... [more ▼]

Colloidal systems are bubbles, droplets, or/and particles dispersed in a continuous media, which are encountered in nature, biological system, and manufactured products. As site of interfaces between at least two bulk phases, their formation and stability need the presence of amphiphilic molecules. Carbohydrate-based surfactants (CBS) take part of these groups of compound having numerous attractive features: an abundance of precursor raw material sources, an excellent environmental compatibility, and a possible quasi-unlimited design of their molecular structure and geometry by different preparation routes. Numerous properties and activities including the aptitude to form and stabilize colloidal systems are therefore expected from a wide range of CBS compounds. Screening of their interfacial behaviors, which govern their functionalities in colloidal system properties, are then relevant in fundamental and practical point of view. In this chapter, interfacial properties of uronic acid-based surfactants are presented as examples of screening approaches. Experimental measurements of both dynamic and equilibrium properties at air-liquid and liquid-liquid interfaces, as well as a computational approach are reported. [less ▲]

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See detailScreening of Basic Properties of Amphiphilic Molecular Structures for Colloidal System Formation and Stability: The Case of Carbohydrate-Based Surfactants
Razafindralambo, Hary ULiege; Blecker, Christophe ULiege; Paquot, Michel ULiege

in Nagarajan, Ramananthan (Ed.) Amphiphiles: Molecular Assembly and Applications (2011, September 19)

Colloidal systems are bubbles, droplets, or/and particles dispersed in a continuous media, which are encountered in nature, biological system, and manufactured products. As site of interfaces between at ... [more ▼]

Colloidal systems are bubbles, droplets, or/and particles dispersed in a continuous media, which are encountered in nature, biological system, and manufactured products. As site of interfaces between at least two bulk phases, their formation and stability need the presence of amphiphilic molecules. Carbohydrate-based surfactants (CBS) take part of these groups of compound having numerous attractive features: an abundance of precursor raw material sources, an excellent environmental compatibility, and a possible quasi-unlimited design of their molecular structure and geometry by different preparation routes. Numerous properties and activities including the aptitude to form and stabilize colloidal systems are therefore expected from a wide range of CBS compounds. Screening of their interfacial behaviors, which govern their functionalities in colloidal system properties, are then relevant in fundamental and practical point of view. In this chapter, interfacial properties of uronic acid-based surfactants are presented as examples of screening approaches. Experimental measurements of both dynamic and equilibrium properties at air-liquid and liquid-liquid interfaces, as well as a computational approach are reported. [less ▲]

Detailed reference viewed: 81 (34 ULiège)