Carboxymethyl function

The viscosity of the solution can be decreased if the tamarind polysaccharide is enzymatically cleaved. The viscosity will also decrease with high DS of hydroxypropyl or carboxymethyl functional groups. 

K. Thakur, M. Ahuja, and A. Kumar, Carboxymethyl functionalization of amylopectin and its evaluation as a nanometric drug carrier, Int. J. Biol. Macromol, 62,25-29,2013. 

Therapeutic Function Mucolytic expectorant nasal antiinfective Chemical Name S-(carboxymethyl)-L-cysteine Common Name —... 

Longer carbon chains can also be added, such as carboxyethyl groups, or carboxypropyl groups. Adding bulky functional components like carboxymethyl and carboxyethyl groups reduces the tendency of the starch to recrystallize. When the starch stays as a gel, a product is softer, and we refer to it as fresh. When the starch regains its crystalline form, the product becomes firmer, and we refer to it as stale. The technical term for this recrystallization is starch retrogradation. 

In general these derivatives are safe, their chemical functions being the glycine moiety the same holds for AT,0-carboxymethyl chitosan, as demonstrated for instance by studies intended to assess the efficacy of W,0-carboxymethyl chitosan to limit adhesion formation in a rabbit abdominal surgery model. The inability of fibroblasts to adhere to N,0-carboxymethyl chitosan-coated surfaces suggests that it may act as a biophysical barrier [135]. 

Utilization of a microfabricated rf coil and gradient set for viscosity measurements has recently been demonstrated [49]. Shown in Figure 4.7.9 is the apparent viscosity of aqueous CMC (carboxymethyl cellulose, sodium salt) solutions with different concentrations and polymer molecular weights as a function of shear rate. These viscosity measurements were made using a microfabricated rf coil and a tube with id = 1.02 mm. The shear stress gradient, established with the flow rate of 1.99 0.03 pL s-1 was sufficient to observe shear thinning behavior of the fluids. 

Dextran cross-linked functionalized by carboxymethylation 10-30 Intratumor direct delivery Doxorubicin mitomycin... 

There are multiple isoforms of the a and p subunits of soluble GC that exhibit distinct tissue and cellular distributions. Most of the isoforms are expressed in brain, including 0Ci 3 and and P3. The p2 subunit is found primarily in lung. This isoform also contains a consensus sequence at its carboxy terminus for isoprenylation or carboxymethyl-ation, which could serve to anchor the protein to the plasma membrane. It has been proposed that specific isoforms of the a and P subunits of GC may form heterodimers with distinct functional and regulatory properties, although this remains to be established with certainty. 

Carboxylic functional polyester curing agents, 10 401-406 Carboxyl ion system, 19 193 Carboxyl-terminated butadiene nitrile, rubbers and, 10 376-375 Carboxymethyl cellulose (CMC),... 

Various compounds bearing a carboxymethyl group at position 1 and a car-boxymethylamino function at position 3, including ACE inhibitors (27, 28), have been claimed as cholecystokinin (CCK)-antagonists [76-78]. Analogous compounds with a 3-hydroxy-2-oxopropyl moiety at position I are also claimed to be useful as antihypertensives and CCK antagonists [79],... 

The particular array of chemical shifts found for the nuclei of a given polymer depends, of course, on such factors as bond orientation, substituent effects, the nature of nearby functional groups, solvation influences, etc. As a specific example, derivatives of the carbohydrate hydroxyl moieties may give rise to chemical shifts widely different from those of the unmodified compound, a fact that has been utilized, e.g., in studies (l ) on commercially-important ethers of cellulose. Hence, as illustrated in Fig, 2, the introduction of an 0-methyl function causes (lU,15) a large downfield displacement for the substituted carbon. This change allows for a convenient, direct, analysis of the distribution of ether groups in the polymer. Analogously, carboxymethyl, hydroxyethyl and other derivatives may be characterized as well... 

Whey protein concentrates (WPC), which are relatively new forms of milk protein products available for emulsification uses, have also been studied (4,28,29). WPC products prepared by gel filtration, ultrafiltration, metaphosphate precipitation and carboxymethyl cellulose precipitation all exhibited inferior emulsification properties compared to caseinate, both in model systems and in a simulated whipped topping formulation (2. However, additional work is proceeding on this topic and it is expected that WPC will be found to be capable of providing reasonable functionality in the emulsification area, especially if proper processing conditions are followed to minimize protein denaturation during their production. Such adverse effects on the functionality of WPC are undoubtedly due to their Irreversible interaction during heating processes which impair their ability to dissociate and unfold at the emulsion interface in order to function as an emulsifier (22). 

Oxalocrotonate tautomerase. This bacterial enzyme, which functions in the degradation of toluene (Chapter 25), is actually an isomerase. It catalyzes rapid interconversion of an unconjugated unsaturated a-oxoacid such as 4-oxalocrotonate with an intermediate enol (which may leave the enzyme) and the isomeric conjugated oxoacid (Eq. 13-31).168-170 A related 5-carboxymethyl-2-hydroxymuconate isomerase... 

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