Water-insoluble chitosan

The cytotoxic activity of chitosan-21-treated lELs was similar to that of oligochitosan-treated lELs, and stronger than that of chitosan-46-treated lELs. Treatment of lELs with oligochitosan, chitosan-21, or chitosan-46 enhanced their cytotoxic activity against sarcoma 180 cells compared with that of untreated lEL, at 10 ig/mL, but neither chitosan-130 nor chitosan-650 (water-insoluble chitosan) had an eifect Fig. (13) . Furthermore, treatment of splenic... 

As a polycation, chitosan spontaneously forms macromolecular complexes upon reaction with anionic polyelectrolytes. These complexes are generally water-insoluble and form hydrogels [90,91]. A variety of polyelectrolytes can be obtained by changing the chemical structure of component polymers, such as molecular weight, flexibility, fimctional group structure, charge density, hydrophilicity and hydrophobicity, stereoregularity, and compatibility, as... 

Zein is a vegetable protein obtained from corn gluten meal. Pure zein powder is odourless, tasteless, hard and water-insoluble. Since it is edible, it finds applications in processed foods and pharmaceuticals, in competition with chitosan and chitin. 

In more recent studies (51, 52) the biopolymer chitosan was used as an emulsifier in food double emulsions. Chitosan has surface activity and seems to stabilize W/OAV emulsions. Chitosan reacts with anionic emulsifiers such as sodium dodecyl sulfate at certain ratios to form a water-insoluble complex that has strong emulsification capabilities. Chitosan solution was used to form double emulsions of OAV/0 as intermediates fi om which by a simple procedure of stripping the water the authors formed interesting porous spherical particles of chitosan (52). 

Although chitosan has very strong biological activities in many fields, the water-insoluble property of chitosan is disadvantageous for its wide application. Therefore, chitosan derivatives with water-soluble and functional property have been developing for food additives and new drug candidates. As shown in Figure 18.5, amino-derivatized chitosan derivatives were prepared in addition of amino... 

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