Yeast proteins may reversibly aggregate like amphiphilic molecules

Marine polysaccharides are part of the huge seaweeds resources and present many applications for several industries. In order to widen their potential as additives or bioactive compounds, some structural modifications have been studied. Among them, simple hydrophobization reactions have been developed in order to yield to grafted polysaccharides bearing acyl-, aryl-, alkyl-, and alkenyl-groups or fatty acid chains. The resulting polymers are able to present modified physicochemical and/or biological properties of interest in the current pharmaceutical, cosmetics, or food fields. This review covers the chemical structures of the main marine polysaccharides, and then focuses on their structural modifications, and especially on hydrophobization reactions mainly esterification, acylation, alkylation, amidation, or even cross-linking reaction on native hydroxyl-, amine, or carboxylic acid functions. Finally, the question of the necessary requirement for more sustainable processes around these structural modulations of marine polysaccharides is addressed, considering the development of greener technologies applied to traditional polysaccharides.

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Luminescent Supramolecular Nano- or Microstructures Formed in Aqueous Media by Amphiphile-Noble Metal Complexes

Journal of Nanomaterials ◽

10.1155/2020/5395048 ◽

2020 ◽

Vol 2020 ◽

pp. 1-24 ◽

Cited By ~ 1

Author(s):

Carmen Cretu ◽

Loredana Maiuolo ◽

Domenico Lombardo ◽

Elisabeta I. Szerb ◽

Pietro Calandra

Keyword(s):

Noble Metal ◽

Smart Materials ◽

Self Assembly ◽

Noble Metals ◽

Photophysical Properties ◽

Aqueous Media ◽

Molecular Architecture ◽

Stimuli Responsive ◽

Panoramic View ◽

Amphiphilic Molecules

The involvement of metal ions within the self-assembly spontaneously occurring in surfactant-based systems gives additional and interesting features. The electronic states of the metal, together with the bonds that can be established with the organic amphiphilic counterpart, are the factors triggering new photophysical properties. Moreover, the availability of stimuli-responsive supramolecular amphiphile assemblies, able to disassemble in a back-process, provides reversible switching particularly useful in novel approaches and applications giving rise to truly smart materials. In particular, small amphiphiles with an inner distribution, within their molecular architecture, of various polar and apolar functional groups, can give a wide variety of interactions and therefore enriched self-assemblies. If it is joined with the opportune presence and localization of noble metals, whose chemical and photophysical properties are undiscussed, then very interesting materials can be obtained. In this minireview, the basic concepts on self-assembly of small amphiphilic molecules with noble metals are shown with particular reference to the photophysical properties aiming at furnishing to the reader a panoramic view of these exciting problematics. In this respect, the following will be shown: (i) the principles of self-assembly of amphiphiles that involve noble metals, (ii) examples of amphiphiles and amphiphile-noble metal systems as representatives of systems with enhanced photophysical properties, and (iii) final comments and perspectives with some examples of modern applications.

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Benchmarking a self-consistent field theory for small amphiphilic molecules

Soft Matter ◽

10.1039/c2sm26352a ◽

2012 ◽

Vol 8 (38) ◽

pp. 9877 ◽

Cited By ~ 10

Author(s):

Russell B. Thompson ◽

T. Jebb ◽

Y. Wen

Keyword(s):

Field Theory ◽

Amphiphilic Molecules ◽

Consistent Field ◽

Self Consistent ◽

Self Consistent Field ◽

Self Consistent Field Theory

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Localization of transmembrane multiblock amphiphilic molecules in phase-separated vesicles

Faraday Discussions ◽

10.1039/c8fd00022k ◽

2018 ◽

Vol 209 ◽

pp. 315-328 ◽

Cited By ~ 1

Author(s):

Kazushi Kinbara ◽

Kaori Umetsu ◽

Hiroki Sonobe ◽

Takahiro Muraoka ◽

Naofumi Shimokawa ◽

...

Keyword(s):

Amphiphilic Molecules

Multiblock-amphiphiles preferentially distribute in the Ld phase and encourage delocalization of cholesterol in both the Ld and Lo phases.

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Distribution of Some Selected Surface Active Agents (SAAs) in the Aquatic and Global Environment with Their Toxic Impact: A Comprehensive Review

Journal of Ravishankar University (Part-B) ◽

10.52228/jrub.2020-33-1-6 ◽

2020 ◽

Vol 33 (1) ◽

pp. 31-46

Author(s):

Ramsingh Kurrey ◽

Anushree Saha ◽

Manas Kanti Deb

Keyword(s):

Surface Waters ◽

Anaerobic Degradation ◽

River Waters ◽

Toxic Impact ◽

Amphiphilic Molecules ◽

Surface Active Agents ◽

Soils And Sediments ◽

Surface Active ◽

Soil Sediments ◽

Dispersing Agents

Surface active agents (SAAs) are a class of compounds, which find various applications in different fields of human activities. Surfactants are generally amphiphilic molecules, which are strongly adsorbed at interfaces between the phases. Surfactants windily used as detergency, emulsion, stabilizing and dispersing agents have led to the discharge of highly contaminated wastewaters in aquatic environment. Once reached in the various compartments of the environment such as rivers, lakes, soils, and sediments, surfactants can undergo aerobic or anaerobic degradation. Concentrations of surfactants in wastewaters, river waters, and sewage waters can range milligrams in maximum cases, while it reaches several grams in sludge, soil and sediments in environments. The environmental facts of SAAs and concentration in surface waters, soils or sediments are reviewed in details. This review provides information on levels of surface-active agents in various environmental samples including soil, sediments, sewage wastewater, river wastewater and aerosols.

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Various Self-Assembly Behaviors of Amphiphilic Molecules in Ionic Liquids

Ionic Liquids - Current State of the Art ◽

10.5772/59095 ◽

2015 ◽

Author(s):

Bin Dong ◽

Yanan Gao

Keyword(s):

Ionic Liquids ◽

Self Assembly ◽

Amphiphilic Molecules

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Specific Binding of Large Aggregates of Amphiphilic Molecules to the Respective Antibodies

Langmuir ◽

10.1021/la700414z ◽

2007 ◽

Vol 23 (16) ◽

pp. 8485-8490 ◽

Cited By ~ 24

Author(s):

Alexei Nabok ◽

Anna Tsargorodskaya ◽

Alan Holloway ◽

Nikolay F. Starodub ◽

Anna Demchenko

Keyword(s):

Specific Binding ◽

Amphiphilic Molecules

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Modelling the dynamics of a minimal protocell container

International Journal of Astrobiology ◽

10.1017/s1473550405002478 ◽

2005 ◽

Vol 4 (1) ◽

pp. 81-91 ◽

Cited By ~ 1

Author(s):

Martin Nilsson Jacobi ◽

Steen Rasmussen ◽

Kolbjørn Tunstrøm

Keyword(s):

Self Assembly ◽

Large Scale ◽

Lattice Gas ◽

Three Dimensional ◽

Initial Distribution ◽

Energy Potential ◽

Time Dynamics ◽

Amphiphilic Molecules ◽

Head Groups ◽

Simplifying Assumptions

This paper is a discussion on how reaction kinetics and three-dimensional (3D) lattice simulations can be used to elucidate the dynamical properties of micelles as a possible minimal protocell container. We start with a general discussion on the role of molecular self-assembly in prebiotic and contemporary biological systems. A simple reaction kinetic model of a micellation process of amphiphilic molecules in water is then presented and solved analytically. Amphiphilic molecules are polymers with hydrophobic (water-fearing), e.g. hydrocarbon tail groups, and hydrophilic (water-loving) head groups, e.g. fatty acids. By making a few simplifying assumptions an analytical expression for the size distribution of the resulting micelles can be derived. The main part of the paper presents and discusses a lattice gas technique for a more detailed 3D simulation of molecular self-assembly of amphiphilic polymers in aqueous environments. Water molecules, hydrocarbon tail groups and hydrophilic head groups are explicitly represented on a three-dimensional discrete lattice. Molecules move on the lattice proportional to their continuous momentum. Collision rules preserve momentum and kinetic energy. Potential energy from molecular interactions are also included explicitly. The non-trivial thermodynamics of large-scale and long-time dynamics are studied. In this paper we specifically demonstrate how, from a random initial distribution, micelles are formed and grow until they destabilize and can divide. Eventually a steady state of growing and dividing micelles is formed. Towards the end of the paper we discuss the relevance of the presented results to the design of a minimal artificial protocell.

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