Carbohydrates function

Dried blends of whole egg and yolk with carbohydrates have sucrose or com symp added to the Hquids before spray-drying. Such carbohydrates (qv) preserve the whipping properties of whole egg and yolk by keeping the fat in an emulsified state. Com symp also gives anticaking characteristics, better flowabiHty, and improved dispersibiHty in water. Dried blends of egg and carbohydrate function weU in emulsified, as weU as unemulsified, sponge cakes. 

F. J. Feher, K. D. Wyndham, and D. J. Knauer, Synthesis, characterization and lectin binding study of carbohydrate functionalized silsesquioxanes, Chem. Commun. (1998) 2393-2394. 

M. L. Wolfenden and M. J. Cloninger, Carbohydrate-functionalized dendrimers to investigate the predictable tunability of multivalent interactions, Bioconjug. Chem., 17 (2006) 958-966. 

The following sections describe fluorescent biotinylation reagents that can be used to study carbohydrate function and interactions. 

First, the above-mentioned sensors have major drawbacks, as the detection and recognition event is a function of the nature and characteristics of the side chains, and the side chain functionalization of the CP requires advanced synthesis and extensive purification of numerous monomeric and polymeric derivatives. Second, this generation of sensors primarily employed optical absorption as the source for detection, resulting in lower sensitivity when compared with other sensing systems for biological processes. However, the use of fluorescence detection within these sensing systems could justify continued development. More recent examples include a fluorescent polythiophene derivative with carbohydrate functionalized side chains for the detection of different bacteria [15] and novel synthesis schemes for ligand-functionalization of polythiophenes [16]. 

Disney M, Zheng J, Swager TM, Seeberger P (2004) Detection of bacteria with carbohydrate-functionalized fluorescent polymers. J Am Chem Soc 126 13343-13346... 

Carbohydrates are among the most abundant constituents of plants, animals, and microorganisms. Polymeric carbohydrates function as important food reserves, and as stmctural components in cell walls. Animals and most microorganisms are dependent upon the carbohydrates produced by plants for their very existence. Carbohydrates are the first products formed in photosynthesis, and are the products from which plants S5mthesize their own food reserves, as well as other chemical constituents. These materials then become the foodstuffs of other organisms. The main pathways of carbohydrate biosynthesis and degradation comprise an important component of... 

Then, in 1987, Dotz reported an improved procedure for this transformation, for which the use of Et20 as solvent improved the yield of the cyclic carbene complexes considerably [12]. For example, the five-membered Fischer-type carbene complex 29 (n=l) was prepared in 58 66% yield by the reaction of preformed M(CO)5(L) (M = Cr, W, L = Et20) and 3-butynol in Et20 at room temperature. The six-membered cyclic carbene complex could also be prepared by this method. This method has been applied to the preparation of functionalized cyclic Fischer-type carbene complexes from the corresponding alkynols. For example, Dotz et al. reported the preparation of various carbohydrate-functionalized cyclic Fischer-type carbene complexes, one of which is shovm in Scheme 5.9. 

Guo CX, Boullanger P, Jiang L, Liu T. Colorimetric detection of WGA in carbohydrate-functionalized polydiacetylene Langmuir-Schaefer films. Colloids Surf Physicochem Eng Asp 2007 293 152-156. 

Efforts to understand and to modulate physiologically relevant protein-carbohydrate interactions have led to the synthesis of many glycosylated frameworks (Zanini and Roy 1998a Mann and Kiessling 2001 Choi 2004 Wittmann 2004). In order for a synthetic, carbohydrate-functionalized framework to be successfully used for binding to proteins, the carbohydrates on the framework must be appropriately... 

Figure 13.4 A schematic showing some of the frameworks that have been reported for the study of protein-carbohydrate interactions. Carbohydrates are represented as cyclohexane. (Top) Glycodendrimer, carbohydrate-functionalized nanoparticle, and star polymer. (Bottom) Linear glycopolymer, carbohydrate-functionalized protein, and carbohydrate-functionalized surface.

Experiments with sequential additions of NCS-TEMPO plus other isothiocyanates indicate that end groups are randomly distributed in relation to one another using this methodology. Even mannose-functionahzed dendrimers appear to have a random end-group distribution (see below). As with any random population, it is possible that some carbohydrate-functionalized dendrimers wUl have higher activity in binding studies than other populations. 

Multivalent protein-carbohydrate interactions mediate many intercellular recognition processes. In order to study and to modulate multivalent protein-carbohydrate interactions, many carbohydrate-functionalized frameworks and systems have been synthesized. The glycodendrimer is one important glycosystem that has been used to study lectin binding. For our work, glycodendrimers based on the PAMAM framework are ideal because of the inherently flexible nature of PAMAM and because of the ease with which PAMAMs can be functionalized with carbohydrates. 

Borrachero et al. (180) prepared a number of sugar isoxazolidines by the reaction of carbohydrate-functionalized nitrones with nitroalkenes (Scheme 1.33). They found a matched pair of chiral sugar cycloaddition reaction partners to be... 

The pharmacophoric and the hydrophilic and lipophilic profiles of the Saa scaffolds can be manipulated by the substitution pattern of the carbohydrate functionalities, e.g. Saa with nonfunctionalized hydroxy groups are more hydrophilic compared to benzylated Saa which can act as mimetic for the Phe residue.1931... 

M. Kiso Synthetic ganglioside probes versatile tools for the elucidation of carbohydrate functions... 

Noncovalent wrapping with polysaccharides is another commonly used approach in the carbohydrate functionalization and solubilization of carbon nanotubcs.39-42 For example, Liu et al. used alginic acid (AA), a natural polysaccharide constituted with repeated (3-D-mannuronic acid ((3M) and a-L-guluronic acid (aG) segments, to... 

William Mills described a similar convention to depict the structures of monosaccharides. While the ring atoms of the Haworth projections are oriented perpendicular to the paper, Mills chose to depict the carbon skeleton in the plane of the paper (Fig. 1.5). Although Fischer, Haworth, and Mills projections are useful tools for depicting the structures of carbohydrates, the planar nature of these representations does not provide an accurate picture of the actual geometry of the molecules. In order to understand carbohydrate function and reactivity, recognition of each distinct conformation and the properties associated with it is required [15]. 

The benzannulation approach has been applied to aromatic molecules of biological interest. Alkynes bearing porphyrin (for example 37) [51a, 51b], ferrocene (for example 39) [51c], and carbohydrate functionalities [51d, 51e] have been incorporated into the (hydro)quinone skeleton, as demonstrated for porphyrinyl and ferrocenyl naphthoquinones 38 and 40 (Scheme 18). 

T. Ogawa, J. Polymer Sd., Part A Polymer Chem. 2003, 41(21), 3336-3345. Simplified synthesis of carbohydrate-functional siloxanes via transacetalation. 1. Glucose-functional siloxanes . 

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