Tannin-Mordant Coloration with Matcha (camelia sinensis) and Iron(II)-Lactate on Human Hair Tresses.

The aim of this work was to optimize our natural hair dyeing system which we described in our previous work and to compare with other dyeing systems. Therefore, we investigated concentration limits of matcha and mordant and compared this new dyeing method with commercial permanent systems on the market. Completely unpigmented hair tresses were dyed with matcha powder (camelia sinensis) and iron(II)-lactate. To investigate the wash fastness and concentration limits, the differently dyed hair tresses were spectrophotometrically measured. The comparison of the damage potential for which cysteic acid is an indicator was measured by NIR. The concentration of matcha and mordant are responsible for the intensity of the color results. The higher the matcha or the mordant concentration, the darker the color results of the dyed hair tresses. Hair damage of matcha mordant dyeing is comparable with results of commercial permanent hair coloration systems. Moreover, the results of wash fastness of matcha mordant dyed hair tresses is comparable and even better by tendency to permanent colored hair tresses.

Cholest-5-en-3ß-yl 3-(4-eth-oxy-phen-yl)prop-2-enoate.

In the asymmetric unit of the title compound, C(38)H(56)O(3), there are two symmetry-independent mol-ecules that differ in the rotation angle along the C-O bond between the 3-(4-eth-oxy-phen-yl)prop-2-enoate and cholest-5-en-3ß-yl groups by 169.3 (3)°. In both mol-ecules, steroid ring B adopts a half-chair conformation, rings A and C adopt a chair conformation and ring D exists in an envelope form. The two symmetry-independent mol-ecules pack in the crystal into separate layers parallel to (-102) with their long axis parallel to the [201] direction. Short inter-molecular C-H⋯O and C-H⋯π contacts are observed.

2-O-Monoalkyl isosorbide ethers with C8, C10, C12 and C14 chain lengths.

The title compounds, 6-(octyloxy)hexa-hydro-furo[3,2-b]furan-3-ol, C14H26O4, 6-(decyl-oxy)hexa-hydro-furo[3,2-b]furan-3-ol, C16H30O4, 6-(do-decyl-oxy)hexa-hydro-furo[3,2-b]furan-3-ol, C18H34O4, and 6-(tetra-decyl-oxy)hexa-hydro-furo[3,2-b]furan-3-ol, C20H38O4, consist of a polar headgroup (isosorbide) and a lipophilic alkyl chain linked via an ether bridge. Isosorbide is a biobased diol, containing two fused furan rings. One inter-molecular hydrogen bond connects the mol-ecules between the free endo hy-droxy group and the opposing ether oxygen of the V-shaped head group. Thus the mol-ecule layers inter-lock like in a herringbone pattern parallel to the bc plane.

Structural polymorphism of hydrated monoacylated maltose glycolipids.

The physico-chemical properties of three fully hydrated monoacyl maltoside glycolipids were investigated with Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and small-angle X-ray scattering (SAXS). The different synthesized maltoside glycoconjugates vary in the length and saturation of the fatty acid moiety, whereas the constant head group region contains a beta-linked maltose with a OC(2)-NH spacer. The compounds with saturated acyl chains showed a complex pattern of temperature-dependent behaviour, regarding the adopted three-dimensional aggregate structure of the molecules and the main phase transition from the gel to liquid crystalline phase of the acyl chains. A substitution of the saturated acyl chain with an unsaturated acyl chain led to a complete change of the structural preferences, from a high ordered stacking of the bilayers to an unilamellar arrangement of completely disordered and fluid membranes. The presence of the NH group in the spacer, compared to the compounds lacking the NH group allows the formation of a hydrogen bonding network, which influences the observed phase properties. The results of these studies of the hydrated monoacylated maltose glycolipids are discussed in relation to the thermotropic phase properties of the pure compounds in the absence of water.

Structural polymorphism of hydrated ether-linked dimyristyl maltoside and melibioside.

The structural polymorphism of two selected disaccharide glycolipids with a maltose (DMMA) and a melibiose (DMME) carbohydrate headgroup linked to dimyristyl alkyl chains were investigated by FTIR-spectroscopy, differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS) and film-balance measurements. The compounds displayed thermotropic multilamellar phases. In the gel phase, DMMA formed also a crystalline phase of orthorhombic symmetry, and DMME an interdigitated phase. The gel to liquid crystalline phase transition temperature T(c) of DMMA depended on the storage and hydration conditions, a precooled sample having a T(c) around 45 degrees C, and a freshly prepared sample around 33 degrees C. In contrast, the phase transition temperature for the gel to liquid crystalline phase of DMME was always found at 24 degrees C. Surface pressure isotherms of the lipids on water and buffer showed that DMMA covers only a small surface area (approximately 35A(2)) whereas DMME requires 50 A(2) of space on the surface. Films of DMMA can be compressed up to a maximum compressibility Pi(max) of 54 mN m(-1) whereas the tilted DMME forms less stable films with Pi(max) of 34 mN m(-1). These different structural characteristics reflect the different conformations of the disaccharide head groups. The presence of the alpha1-->4 linked maltose head group in DMMA and an alpha1-->6 linked melibiose head group in DMME induces geometrical structures ranging from a slightly wedge-shaped towards a more tilted structure, and as a consequence of Israelachvilis packing model, to the formation of different phases. In addition, the structural constraints of DMME allow the formation of a phase with interdigitated hydrocarbon chains.

Structural preferences of dioleoyl glycolipids with mono- and disaccharide head groups.

The structural preferences of 1,2-dioleoyl-sn-glycerol glycolipids with glucose, galactose, maltose, and cellobiose as sugar head group were investigated under near physiological conditions with Fourier-transform infrared spectroscopy (FT-IR) and synchrotron radiation small-angle X-ray scattering (SAXS). Whereas all glycolipids have a very high fluidity at temperatures above 0 degrees C, the mono- and disaccharide compounds differ considerably in their aggregate structures. The monosaccharide compounds adopt only inverted hexagonal (H(II)) structures in the temperature range 5-70 degrees C, while the disaccharide compounds adopt only multilamellar structures. Since these and similar glycolipids are frequently found in nature, these data should be of relevance for the function of their host cell membranes.

Comparison of the supramolecular structures of two glyco lipids with chiral and nonchiral methyl-branched alkyl chains from natural sources.

Two alkyl glycosides with the same type of disaccharide headgroups (melibiose) and different methyl-branched alkyl chains, short chiral [(2R,4R,6R,8R)-2,4,6,8-tetramethyldecyl, extracted from an animal source] and long nonchiral (3,7,11,15-tetramethylhexadecyl, from a plant source), were synthesized. The supramolecular aggregate structure formed in dilute solutions was investigated by small-angle neutron scattering and surface tension measurements. The lyotropic phase diagram was studied by differential scanning calorimetry and water penetration scans. The thermotropic phase behavior was investigated by polarizing microscopy. The compounds showed unusual phase behavior: (i) The liquid-crystalline polymorphism is reduced to only form smectic A phases in the pure state; the formation of lyotropic phases such as hexagonal or lamellar phases was not observed. (ii) The compound with the longer nonchiral alkyl chain is more soluble in water than the one with the shorter chiral chain, most likely because of the different flexibilities of the chains. (iii) For the long-chain compound, the formation of micelles is observed, whereas the short-chain compound forms large disklike/bilayer aggregates. The method of methylation of the chain controls the self-assembly and can explain different biological functions for either plants (variable temperature) or animals (constant temperature).

Synthesis and mesomorphic properties of glycosyl dialkyl- and diacyl-glycerols bearing saturated, unsaturated and methyl branched fatty acid and fatty alcohol chains. Part I. Synthesis.

Glycosyl dialkyl- and diacyl-glycerols bearing saturated, unsaturated or chiral methyl branched chains in the tail and disaccharide and trisaccharide carbohydrate headgroups were synthesised. Standard procedures were used for the preparation of the educts and the glyco lipids: trichloracetimidate procedure for the preparation of long-chained compounds, glycosylation using the beta-peracetate and boron trifluoride etherate was successful for the preparation of lipids with a medium-alkyl chain length. Preparation of the ester was afforded in a multi-step synthesis according to published procedures. Thus, several lipids were synthesised in a few synthetic steps in good yields. The introduction of unsaturated or methyl branched chains lead to liquid crystallinity at ambient temperature, because these compounds will be used as model compounds for biological systems. The biophysical properties of these compounds will be reported in a following paper.

Synthesis and mesomorphic properties of glycosyl dialkyl- and diacyl-glycerols bearing saturated, unsaturated and methyl branched fatty acid and fatty alcohol chains. Part II. Mesomorphic properties.

The biophysical properties of a series of glycosyl dialkyl- and diacyl-glycerols bearing unsaturated or chiral methyl branched chains in the tail, and di- and trisaccharide carbohydrate headgroups are described. Thermotropism was investigated by polarising microscopy, the lyotropism was investigated by small angle X-ray diffraction and by the contact preparation method, and the gel to liquid crystalline phase transition by FT-IR-spectroscopy. The compounds displayed thermotropic Smectic A (SmA), cubic and columnar phases, whereas in the lyotropic phase diagram lamellar, hexagonal and cubic phases are found. The introduction of unsaturated or methyl branched chains leads to liquid crystallinity at ambient temperature. The difference between the 1,3-oleyl-glycerol maltoside and the corresponding 1,2-oleoyl-glycerol maltoside is small.

Structures of micelles formed by synthetic alkyl glycosides with unsaturated alkyl chains.

Three new alkyl glycosides with similar molecular structures (oleyl and oleoyl alkyl chains and various head groups: disaccharide, trisaccharide and disaccharide with an additional amidoethoxy spacer) were synthesized and their supramolecular structure in aqueous solution was investigated. Small angle neutron scattering, surface tension measurement and the contact preparation method were applied to get molecular structure-property relationships. Although the chemical structures differ only in small details, their CMC values, lyotropic phase behaviour, surface area per surfactant molecule in the micelle and at the liquid-air interface, and the size and shape of the micelles are very different. We have found three different types of aggregates: spherical, cylindrical and polymer-like micelles in dilute solutions.

Crystal structure of cholest-5-en-3ß-yl 3-(2,4-dimeth-oxy-3-methyl-phen-yl)prop-2-enoate.

In the title compound, C39H58O4, the steroid rings A and C adopt a chair conformation, while ring B adopts a half-chair conformation, and ring D has an envelope conformation, with the methyl-substituted C atom as the flap. In the crystal, mol-ecules pack within layers parallel to (100), with their long axis parallel to the [101] direction. Adjacent layers are linked via C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming a three-dimensional framework.

Self-Organisation, Thermotropic and Lyotropic Properties of Glycolipids Related to their Biological Implications.

Glycolipids are amphiphilic molecules which bear an oligo- or polysaccharide as hydrophilic head group and hydrocarbon chains in varying numbers and lengths as hydrophobic part. They play an important role in life science as well as in material science. Their biological and physiological functions are quite diverse, ranging from mediators of cell-cell recognition processes, constituents of membrane domains or as membrane-forming units. Glycolipids form an exceptional class of liquid-crystal mesophases due to the fact that their self-organisation obeys more complex rules as compared to classical monophilic liquid-crystals. Like other amphiphiles, the supra-molecular structures formed by glycolipids are driven by their chemical structure; however, the details of this process are still hardly understood. Based on the synthesis of specific glycolipids with a clearly defined chemical structure, e.g., type and length of the sugar head group, acyl chain linkage, substitution pattern, hydrocarbon chain lengths and saturation, combined with a profound physico-chemical characterisation of the formed mesophases, the principles of the organisation in different aggregate structures of the glycolipids can be obtained. The importance of the observed and formed phases and their properties are discussed with respect to their biological and physiological relevance. The presented data describe briefly the strategies used for the synthesis of the used glycolipids. The main focus, however, lies on the thermotropic as well as lyotropic characterisation of the self-organised structures and formed phases based on physico-chemical and biophysical methods linked to their potential biological implications and relevance.

Antiferroelectric ordering of amphiphilic glycolipids in bent-core liquid crystals.

Lipids are the main constituents of biological cell membranes, and their liquid crystalline properties play a crucial role in cell functions. We have discovered that dodecyl-beta-D-glucopyranoside glycolipid layers can be electrically polarized in supramolecular structures of glycolipid and bent-core ("banana-shape") molecules. Interestingly the glycolipid molecules, known to be excellent chiral dopants, are not able to transfer their chirality to the bent-core layers. Our observations indicate that glycolipid molecules self-assemble into pairs of tilted and antiferroelectric double layers, sandwiched between layers of bent-core molecules. These systems may provide a basis for understanding "bioferroelectricity," which is important in biological cell membrane functions.

Mixed micelles formed by SDS and a bolaamphiphile with carbohydrate headgroups.

The formation of micelles in aqueous mixtures of a carbohydrate-based bolaamphiphile and sodium dodecyl sulfate (SDS) is investigated by surface tension and small-angle neutron scattering. The obtained values of critical micelle concentration (CMC) are analyzed within the framework of regular solution theory. Synergetic interactions between the bolaamphiphile and SDS are observed (parameter beta is negative; a minimum in the plot CMC vs composition). SANS data are collected for mixtures containing protonated and deuterated SDS. This gives us the possibility to conclude that mixed micelles with a homogeneous distribution of surfactant molecules within the micelle are formed. The shape of the micelles is found to be slightly oblate.

Sugar Amphiphiles as Revealing Dopants for Induced Chiral Nematic Lyotropic Liquid Crystals.

The existence of phase chirality in lyotropic liquid crystals still raises questions. The mechanisms behind the transfer of chirality throughout the long-range orientational order are not yet obvious. Guest/host systems with chiral dopants in achiral host phases offer the capability of systematic investigations. We demonstrate that the large amount of accessible sugar amphiphiles exhibits remarkable structure/property relations. Their helical twisting power HTP increases strongly with the number of sugar units of a dopant molecule. The spatial range of the chirality information reaching from a chirally doped micelle to adjacent aggregates is essential for the development of phase chirality. The induced twist of the lyotropic nematic host phase is highly sensitive to small changes of the sugar type (e.g., galacto- to glucopyranose). Depending on the nature of the host phase, either the alpha- or the beta-linkage of the sugar to the hydrophobic moiety of the sugar dopant results in larger HTP values. We propose that our amphiphilic sugar derivatives act like antennae to transfer chirality information. Their effectiveness as chiral dopants is due to a hydrophobic anchoring within the micelles and an extension of their chiral moiety far into the intermicellar region. The chirality transfer works especially well if the hydrophilic and chiral sugar moieties are oriented toward a neighboring micelle in the direction of the helix axis. Copyright 2001 Academic Press.