Medical Research

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Chitosan is currently the focus of much medical research, as it is a polyglucosamine (the second-most-common dietary fiber, after cellulose).[1] Studies have shown that chitosan has the following properties:

  • As a soluble dietary fiber, it increases gastrointestinal lumen viscosity[1] and slows down the emptying of the stomach.
  • It alters bile acid composition, increasing the excretion of sterols and reducing the digestibility of ileal fats.[2][3][4] It is unclear how chitosan does this, but the currently favored hypotheses involve the increase of intestinal viscosity or bile acid-binding capacity.[5]
    • Chitosan is relatively insoluble in water, but can be dissolved by dilute acids, which would make it a highly-viscuous dietary fiber.[5] Such fibers might inhibit the uptake of dietary lipids by increasing the thickness of the boundary layer of the intestinal lumen, which has been observed in animal experiments.[6]
    • Having very few acetyl groups, chitosan contains cationic groups.[8] This may cause chitosan to have bile acid-binding capacity, which causes mixed micelles to be entrapped or disintegrated in the duodenum and ileum.[5] This would interrupt bile acid circulation, causing reduced lipid absorption and increased sterol excretion, which has also been observed in animal experiments.[4][5][6]

References

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  1. ^ Knorr, D. (January 1991). "Recovery and utilization of chitin and chitosan in food processing waste management". Food Technology. 45 (1): 114–122.
  2. ^ Y. Fukada, K. Kimura, and Y. Ayaki (1991). "Effect of chitosan feeding on intestinal bile acid metabolism in rats". Lipids. 26 (5). Springer Berlin / Heidelberg: 395–399. doi:10.1007/BF02537206. ISSN (Online) 1558-9307 (Online). {{cite journal}}: Check |issn= value (help); Unknown parameter |issn2= ignored (help)CS1 maint: multiple names: authors list (link)
  3. ^ Maezaki, Y., Tsuji, K., Nakagawa, Y., Kawai, & Akimoto, M. (1993). "Hypocholesterolemic effect of chitosan in adult males". Bioscience, Biotechnology and Biochemistry. 57 (9): 1439–1444. ISSN 0916-8451.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. ^ a b Razdan A., Pettersson, D. (1994). "Effect of chitin and chitosan on nutrient digestibility and plasma lipid concentrations in broiler chickens". British Journal of Nutrition. 74: 277–288. doi:10.1079/BJN19940029.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. ^ a b c d I. Furda (1990). "Interaction of dietary fiber with lipids--mechanistic theories and their limitations". Advances in Experimental Medicine and Biology. 270. Plenum Press: 67–82. ISSN (Print) 0065-2598 (Print). PMID 1964019. {{cite journal}}: Check |issn= value (help)
  6. ^ a b Ikeda, I. : Sugano, M. : Yoshida, K. : Sasaki, E. : Iwamoto, Y. : Hatano, K. (March 1993). "Effects of chitosan hydrolysates on lipid absorption and on serum and liver lipid concentration in rats". Agriculture and Food Chemistry. 41 (3): 431–435. ISSN 0021-8561.{{cite journal}}: CS1 maint: multiple names: authors list (link)