Surfactants from sucrose

Occlusion is a condition that could affect drug transport from niosomes and through the stratum corneum. Such an effect was reported for saturated estradiol niosomal formulations composed of polyoxyethylene alkyl ether surfactants and sucrose ester surfactants with cholesterol and dicetyl phosphate, for which occlusion enhanced the drug human stratum corneum transport [43]. 

In reaction with benzaldehyde or its dimethyl acetal, or benzylidene dibromide, sucrose undergoes conversion into its 4,6-acetal in moderate yield (28-35%).160,161 The transacetalation reaction of dialkyl acetals prepared from unsaturated or aromatic aldehydes can take place under very mild acidic conditions. For example, sucrose-derived monomers or surfactants (variously substituted 4,6-(9-methylidenesucroses) have been prepared146,162 and 4,6-monoacetals incorporating masked aromas or fragrances derived from p-citral or a- or p-ionone were prepared directly from sucrose in high yields.163,164 These latter molecules, whose unsaturated carbonyl system is very susceptible to oxidation, are thus temporarily protected and are readily released under very mild conditions (Scheme 13). 

E. Fanton, C. Fayet, and I. Gelas, Long-chain acetals derived from sucrose as a new class of surfactants, Carbohydr. Res., 298 (1997) 85-92. 

Henkel makes alkyl polyglycoside surfactants from alcohols derived from coconut and palm oils, and glucose derived from cornstarch.277 The preparation can be done with /3-D-glucosidase.278 Sucrose monoesters of long-chain fatty acids can also be made enzymatically.279 A variety of biosurfactants are produced by various organisms that can be grown in culture.280... 

CMK-2 [114] is an ordered mesoporous carbon obtained from sucrose as a source of carbon and SBA-1 silica as template [Fig. 34b)]. Electron diffraction showed that this carbon is composed of c s iirtercoimected with two different types of pores (meso- and micropores). CMK-3 [115] is an ordered mesoporous carbon that was synthesized using SBA-15 mesoporous silica as template and sucrose as carbon source. The structure of CMK-3 was the faithful replica of the mesoporous silica template, as revealed by XRD and TEM. This carbon had a hi BET surface area (1500 n g % and a pore size around 4.5 nm. The systematic control of pore wall thickness of hexagonal mesoporous silica templates (by varying the ratio of surfactants CwTAB and CmEOg, Fig. 35) afforded a close control of the... 

We heard about some new sucrose ester surfactants from Dr. Parker of Tate Lyle, and the stage of the developments of older esters from Mr. Kosaka of the Ryoto group and from Mr. Bobichon from Rhdne-Poulenc. 

The disappearance of sucrose ester surfactants from river water samples was studied by measuring the consequent increase in surface tension. This showed 100% primary biodegradation within 2 days [70,71]. An advantage of sugar fatty acid esters is their ready anaerobic biodegradation. Complete primary biodegradation within 2 days was also observed under anaerobic conditions [70]. 

An easy and sensitive method to measure protein denaturation is to use enzymes as the proteinaceous substrate for the test product. An irritant surfactant incubated with the enzyme will lead to a loss of the enzymatic activity of the protein proportional to the level of irritancy of the surface agent. The better known enzyme inhibition test is using sac-charase as the enzyme, measuring by polarimetry the amount of glucose formed from sucrose in the presence and the absence of the detergent [13]. 

Sucrose and other materials may be separated from sucrose ester surfactants by taking up the mixture in hot methyl ethyl ketone, in which sucrose is insoluble. Acidification and cooling of the solution will cause the sucrose ester to precipitate, while any fatty acid remains soluble (28). Another method calls for washing the mixture with acidic water of high ionic strength. The sucrose esters remain insoluble, while other components of the reaction mixture are dissolved (29,30). 

Two groups of sucrose derivatives of herbicidal acids have been reported. The herbicidal properties of the sucrose esters of (2,4-dichlorophenoxy)-acetic acid and other analogs differed somewhat from the salts of the free herbicide acids. This could be accounted for as being due to differences in solubility and penetration, since it is unlikely, by analogy to the fatty acid esters, that the sucrose esters would remain intact in the plant. 0 The second set of sucrose esters were water-soluble sirups, having surfactant properties, prepared from reaction products of hydroxyethyl ethers of sucrose or diglycidyl ethers of poly(oxyetbylene glycol) with (2,4,5-tri-chlorophenoxy) acetic acid or other herbicidal acids. 1... 

The use of surfactants in the food industry has been known for centuries. Naturally occurring surfactants such as lecithin from egg yolk or soybean and various proteins from milk are used for the preparation of many food products, such as mayonnaise, salad creams, dressing, and desserts. Polar lipids such as monoglycerides have been introduced as emulsifiers for food products. More recently, synthetic surfactants such as sorbitan esters (Spans) and their ethoxylates (Tweens), sucrose esters, have been used in food emulsions. It should be mentioned that the structures of many food emulsions is complex, and in... 

In a detersive system containing a dilute surfactant solution and a substrate bearing a solid polar soil, the first effect is adsorption of surfactant at the soil-bath interface. This adsorption is equivalent to the formation of a thin layer of relatively concentrated surfactant solution at the interface, which is continuously renewable and can penetrate the soil phase. Osmotic flow of water and the extrusion of myelin forms follows the penetration, with ultimate formation of an equilibrium phase. This equilibrium phase may be microemulsion rather than liquid crystalline, but in any event it is fluid and flushable from the substrate surface. This phase change effect explains the detersive behavior of sucrose fatty esters in admixture with alkylarenesulfonates (117). 

The sugars sucrose, fructose and glucose have also been found to affect bubble coalescence. On addition to water these sugars raise the surface tension and are desorbed from the air-water interface. Thus their effect on bubble coalescence equally cannot be described in terms of surfactant-like behaviour and certainly no charge effects are involved. Hence, even if an "explanation" could be found within the confines of the primitive model of electrolytes, that explanation could not accommodate this observation. The reduction in bubble coalescence achieved with increasing concentration is shown in Fig. 3.7. 

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