Sugar ester

Polyoxyethylene sorbitan monoesters (examples in Table 8.22) are used to stabilize o/w emulsions. 

They are obtained, among other methods, by transesterification of fatty acid methyl esters (14 0, 16 0, 18 0 and/or 18 1, double bond position 9) with sucrose and lactose. The resultant mono- and diesters are odorless and tasteless. Depending on their structure, they cover an HLBrange of 7-13, and are used in stabilization of o/w emulsions, or in stabilization of some instant dehydrated and powdered foods. 

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Anthralin [1143-38-0] is acetylated using acetyl chloride in toluene and a pyridine catalyst to furnish 1,8-dihydroxy-lO-acetylanthrone [3022-61-5], an intermediate in the preparation of medications used in treating skin disorders, such as warts, psoriasis, and acne (38). Sugar esters can be similarly prepared from acetyl chloride under anhydrous conditions (39). 

FIGURE 7.13 Several sugar esters important in metabolism. 

Fig. 2.43 Compounds 166-169, quinine relatives from Cinchona. Compound 170, a generalized sugar ester from Lycopersicon pennellii...

Glatter, O. et al.. Sugar-ester nonionic microemnlsion Structural characterization, J. Colloid Interface Sci, 241, 215, 2001. 

Anhydro-D-glucose resulted, as mentioned, from the hydrolytic removal of a halogen atom at C6. Similar hydrolytic scission of sugar esters of carboxylic acids takes place without dehydration and with the liberation of the normal sugar. Thus, saponification of 6-benzoyl- or... 

J. C. Colbert, Sugar Esters Preparation and Application, Noyes Data Corporation, New Jersey, 1974, p. 30. 

Polyoxyethylene sorbitan trioleate (Tween 85) sugar ester (DK-F-110) tetraoxyethylene monodecyl ether (C10E4) polyoxyethylene-p-f-octyl phenol (Triton X-100) pentaethylene glycol dodecyl ether... 

Naoe et al. [239] used the sugar ester DK-F-110, a mixture of sucrose esters of fatty acids, as a nonionic surfactant along with isopropyl alcohol and hexane in a reverse micellar system to extract cytochrome C. This surfactant has a critical micellar concentration of 0.5 g/1 and HLB of 11. Aqueous phase pH was found to have a major role in the forward extraction and optimum extraction was achieved at pH 8.0. However, for optimum back extraction, addition of isopropyl alcohol at 20 vol.% was found to be very essential. Further, the esterification reaction rate of Rhizopus delemar lipase was found to be maximum in DK-F-110 systems and also higher than those obtained in AOT and lecithin-RMs at a water concentration of 0.25 mol l h... 

The rate of phase separation after extraction in AOT-RMs is slow [167]. Keeping this in view, there is a need to study in detail the phase separation kinetics of this reverse micellar system in order to evolve means to enhance the phase separation rate. This is a very important aspect as far as industrial adaptability of RME is concerned, since the slower separation rate may become a bottleneck as in the case of ATPE. One possible approach to enhance phase separation is the application of external fields such as electric, acoustic, and microwave to reverse micellar systems. These are shown to enhance the phase separation rate in the case of ATPE [346-348]. Employing reverse micellar systems which phase separate quickly without the need for any external effort could also be a plausible solution. Some examples of such systems are DTDPA-RMs [237], sugar esters DK-F-110 RMs [239], and NaDEHP-RMs [167,243]. 

Broccoli florets and leafy cruciferous vegetables will be the major source of sugar esters and of conjugated sinapic acid (10 mg/100 g). Tomato and tomato products are likely to be the major source of glucosides at up to 13 mg/100 g in total, and possibly the second richest source of conjugate p-coumaric acid (3 mg/100 g). 

In the reaction of ammonia with l,3,4,5-tetra-0-benzoyl-/3-n-fructopyranose, a significant proportion of benzoic acid was formed, indicating that the ammonolysis of the sugar ester occurred to a certain extent through acyloxy-group rupture. As neither the formation of imidazole nor of pyrazine derivatives (see Section VI,3, p. 124) re-... 

Fehling s solution is reduced at an elevated temperature by all sugar esters including esters of bioses and trioses. 

Pyridine and hydroxylamine separately exert only a weak influence on the highnitrated sugar esters of nitric acid, whereas when they are used together they bring about somewhat violent chemical reaction, as demonstrated by Hayward and Purves [21a],... 

J. B. Lee and T. J. Nolan, Sugar esters. IV. The preparation of chloro esters under essentially neutral conditions, Can. J Chem. 44 1331 (1966). 

It appears that the initial lack of interest in sulfonic esters of carbohydrates can be attributed to the fact that sugar chemists were so accustomed to thinking of sugar esters in terms of carboxylic esters (particularly, acetates and benzoates) that they overlooked an earlier... 

Cinnamic esters are also found as sugar esters, or as esters of a variety of other organic acids. For example, sinapoyl esters represent a class of UV-absorbing compounds in the family of the Brassicaceae. Examples include sinapoyl malate (1.19) present in leaves, and sinapoyl choline (1.20) present in roots (Ruegger and Chappie, 2001). 

Zhao Z, Egashira Y, Sanada H. 2003a. Digestion and absorption of ferulic acid sugar esters in rat gastrointestinal tract. J Agric Food Chem 51 5534-5539. 

Nakajima, T., et al. 1990. Indomethacin sustained-release suppositories containing sugar ester in polyethylene glycol base. Chem Pharm Bull 38 1680. 

L. Bobichon, A sugar ester process and its application in calf feeding and human food additives, in J.L. Hickson (Ed.), Sucrochemistry, ACS Symposium Series, Vol. 41, ACS, Washington, DC, 1977, pp. 115-120. 

G. Garofalakis, B. S. Murray, and D. B. Sarney, Surface activity and critical aggregation concentration of pure sugar esters with different sugar headgroups, J. Colloid Interface Sci., 229 (2000) 391-398. 

M. H. Ali, P. M. Collins, and W. G. Overend, Titanium-mediated methylene transfer reactions on sugar esters, lactones and uloses, Carbohydr. Res., 205 (1990) 428 434. 

K. Bock and C. Pedersen, Reaction of sugar esters with hydrogen fluoride. 13. Preparation of l,6-anhydro-/S-D-gulopyranose derivatives, Acta Chem. Scand., Ser. B, 29 (1975) 181-184. 

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