Kappa carrageenan

A useful property of the red seaweed extracts is their abiUty to form gels with water and milk. Kappa-carrageenan reacts with milk protein micelles, particularly kappa-casein micelles. The thickening effect of kappa-carrageenan in milk is 5—10 times greater than it is in water at a concentration of 0.025% in milk, a weak thixotropic gel is formed. 

Commercial locust bean gum is the ground endosperm of the seeds of the locust bean (carob) tree. The general properties of locust bean gum are similar to those of guar gum. Differences are its low cold-water solubiUty and its synergistic gelation with kappa-carrageenan, furceUaran, and xanthan... 

Harding, S.E. Day, K. Dham, R. Lowe, P.M. 1997a. Further observations on the size, shape and hydration of kappa-carrageenan in dilute solution. Carbohydrate Polymers 32, 81-87. 

Spagnuolo, P. A., Dalgleish, D. G., Goff, H. D., and Morris, E. R. (2005). Kappa-carrageenan interactions in systems containing casein micelles and polysaccharide stabilizers. Food Hydrocolloids 19,371-377. 

Amino acid Secreted by endophytic green alga A. operculata challenged with kappa-carrageenan oligosaccharides L-Asparagine... 

The structures of agarose, iota- and kappa-carrageenan have been determined by x-ray fiber diffraction (24-27). The quality of the diffraction data obtained from each of these three specimens varies considerably and the way in which these data are used in structure determination is outlined here. Diffraction patterns from oriented specimens of agarose, and kappa- and iota-carrageenan are shown in Figure 6 (28). The molecular repeat distances derived from these patterns are listed in Table I. 

Figure 5. Chemical repeating units of (a) agarose, (b) iota-carrageenan, and (c) kappa-carrageenan.

Figure 6. X-ray fiber diffraction patterns from (a) agarose, (b) Ca " iota-carrageenan, and (c) K " kappa-carrageenan. (Reproduced with permission from ref. 28. Copyright 1989 Elsevier.)...

More recently, El Modhy et al. investigated the hydrolysis of sucrose over Kappa carrageenan/acrylic acid graft-copolymers (kC-g-AAc) prepared by y-radiation. They showed that the catalytic activity of the kC-g-AAc was dependent on the reaction temperature [29]. As expected, at 80°C, the activity was higher than at 30°C because of lower diffusional resistance. 

Borgstrom, J., Piculell, L., Viebke, C., Talmon, Y. (1996). On the structure of aggregated kappa-carrageenan helices a study by cryo-TEM, optical rotation and viscometry. International Journal of Biological Macromolecules, 18, 223-229. 

Chronakis, I.S., Piculell, L., Borgstrom, J. (1996). Rheology of kappa-carrageenan in mixtures of sodium and cesium iodide two types of gels. Carbohydrate Polymers, 31, 215-225. 

Musampa, R.M., Alves, M.M., Maia, J.M. (2007). Phase separation, rheology and microstructure of pea protein-kappa-carrageenan mixtures. Food Hydrocolloids, 21, 92-99. 

Rees et al. (25) have extensively examined the solution conformation and interactions of a number of polysaccharides, especially carrageenan fractions. Kappa-carrageenan is unusual as it forms gels when a solution of its potassium salt is cooled. Rees conceives that double helix formation occurs in solution and, interlocking helices develop in the gel state. 

It is possible that gel formation is abetted by insolubility factors within the polysaccharide make up. Kappa-carrageenan is thought to be a barely soluble polysaccharide. It contains enough 3,6-anhydro rings to insolubilize a neutral polysaccharide (Figure 2). Solubility is maintained by the presence of the 4-O-sulfate groups. Yet it appears that... 

Campanella et al. [75] Polyphenols, hydrogen peroxide, KO2, lecithin Olive oil and other vegetable oils Egg yolk Ground soya seed oil Tyrosinase or catalase or superoxide dismutase or phospholipase D/choline oxidase were entrapped in kappa-carrageenan gel Oxygen electrode -... 

Campanella et al. [1] Superoxide radical polyphenols Sulfite Ascorbic acid Wine Superoxide dismutase (SOD), or tyrosinase, or sulfite oxidase, or ascorbate axidase/in a gel-like kappa-carrageenan membrane sandwiched between a cellulose acetate membrane and a dialysis membrane Amperometric Pt electrode for hydrogen peroxide (for superaxide determination)/ +650 mV vs. Ag/AgCl/ Amperometric oxygen electrode (for the rest)/-650 mV vs. Ag/AgCl... 

Campanellae al. [92] Lecithin Soya seed flour, soya seed oil, ground soya seed oil, ground maize germ oil, milk chocolate, soya lecithin in gel capsules, soya lecithin in tablets Phospholipase D and choline oxidase/both immobilised in kappa-carrageenan gel or in dialysis membrane Amperometric gas diffusion electrode for oxygen ... 

The biosensor [1] was obtained by coupling a transducer (an ampero-metric electrode for hydrogen peroxide) with the superoxide dismutase enzyme immobilized in kappa-carrageenan gel. Sandwich the gel containing the enzyme between a cellulose acetate membrane and a dialysis membrane. Secure the whole assembly to the electrode with an O-ring (Fig. 12.1). 

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