Inulin

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Not to be confused with insulin.
Inulin
Identifiers
ChEMBL
ChemSpider
  • none
DrugBank
ECHA InfoCard
 100.029.701 Edit this at Wikidata
KEGG
UNII
Properties
C6nH10n+2O5n+1
Molar mass Polymer; depends on n
Pharmacology
V04CH01 (WHO)
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
1
1
0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Inulins are a group of naturally occurring

glomerular filtration rate.[4]

Origin and history

Inulin is a natural storage carbohydrate present in more than 36,000 species of plants, including

osmotic potential of their cells by changing the degree of polymerization of inulin molecules by hydrolysis. By changing osmotic potential without changing the total amount of carbohydrate, plants can withstand cold and drought during winter periods.[7]

Inulin was discovered in 1804 by German scientist

molecular weight and its resistance to enzymes.[10] Inulin is used to determine glomerular filtration rate of the kidneys.[12]

Chemical structure and properties

Inulin is a heterogeneous collection of

fructo-oligosaccharides, and only called the longer-chained molecules inulin.[7]

Because of the β(2,1) linkages, inulin is not digested by enzymes in the

Oligofructose has 35% of the sweetness of sucrose, and its sweetening profile is similar to sugar. Standard inulin is slightly sweet, while high-performance inulin is not. Its solubility is higher than the classical fibers. When thoroughly mixed with liquid, inulin forms a gel and a white creamy structure, which is similar to fat. Its three-dimensional gel network, consisting of insoluble submicron crystalline inulin particles, immobilizes a large amount of water, assuring its physical stability.[14] It can also improve the stability of foams and emulsions.[6]

Uses

Harvesting and extraction

Chicory root is the main source of extraction for commercial production of inulin. The extraction process for inulin is similar to obtaining sugar from sugar beets.[5] After harvest, the chicory roots are sliced and washed, then soaked in a solvent (hot water or ethanol);[15] the inulin is then isolated, purified, and spray dried. Inulin may also be synthesized from sucrose.[5]

Processed foods

Inulin received no-objection status as

intestinal flora that contribute to maintaining health of the colon.[24][25][26]

Due to the body's limited ability to process fructans, inulin has minimal increasing impact on

blood sugar, and may potentially have use in managing blood sugar-related illnesses, such as metabolic syndrome.[27]

Medical

Inulin and its analog sinistrin are used to help measure kidney function by determining the glomerular filtration rate (GFR), which is the volume of fluid filtered from the renal (kidney) glomerular capillaries into the Bowman's capsule per unit time.[28]

While inulin is the gold standard for measuring the GFR, it is rarely used in practice due to the expense and difficulty in conducting the test; it requires

intravenous (IV) access for the infusion of inulin as well as up to twelve blood samples taken from the patient over the course of four hours.[29] To determine the glomerular filtration rate in humans, a large initial dose of inulin is injected, which is followed by a constant infusion of inulin at a rate which compensates for its loss in the urine, thus maintaining a reasonably constant level in the plasma.[30]: 228  In the United States, creatinine clearance is more widely used to estimate GFR.[31]

A 2017

low-density cholesterol, a biomarker of cardiovascular disease.[27]

Diet and side effects

The side effects of inulin dietary fiber diet, which may occur, usually in sensitive persons, are:[32]

  • Intestinal discomfort, including flatulence, bloating, stomach noises, belching, and cramping
  • Diarrhea
  • Inflammation – inulin can cause an allergy-related type of inflammation in the gut and lungs[33]
  • Anaphylactic allergic reaction (rare) – inulin is used for GFR testing, and in some isolated cases has resulted in an allergic reaction, possibly linked to a food allergy response.[34]

Industrial use

Nonhydrolyzed inulin can also be directly converted to ethanol in a simultaneous saccharification and fermentation process, which may have potential for converting crops high in inulin into ethanol for fuel.[35]

Biochemistry

Inulins are polymers composed mainly of fructose units (fructans), and typically have a terminal glucose. The fructose units in inulins are joined by a β(2→1) glycosidic bond. The molecule is almost exclusively linear, with only a few percent branching.[36]: 58  In general, plant inulins contain between 2 and 70 fructose units[36]: 58  or sometimes as high as 200,[37]: 17  but molecules with less than 10 units are called fructo-oligosaccharides, the simplest being 1-kestose, which has two fructose units and one glucose unit. Bacterial inulin is more highly branched (more than 15% branching) and contains on the order of tens or hundreds of subunits.[37]: 17 

Inulins are named in the following manner, where n is the number of fructose residues and py is the abbreviation for pyranosyl:

  • Inulins with a terminal glucose are known as alpha-D-glucopyranosyl-[beta-D-fructofuranosyl](n-1)-D-fructofuranosides, abbreviated as GpyFn.
  • Inulins without glucose are beta-D-fructopyranosyl-[D-fructofuranosyl](n-1)-D-fructofuranosides, abbreviated as FpyFn.

Hydrolysis of inulins may yield fructo-oligosaccharides, which are oligomers with a degree of polymerization (DP) of 10 or less.

Calculation of glomerular filtration rate

Inulin is uniquely treated by

afferent arteriole that is filtered into Bowman's capsule measured in ml/min.[citation needed
]

It is informative to contrast the properties of inulin with those of

para-aminohippuric acid (PAH). PAH is partially filtered from plasma at the glomerulus and not reabsorbed by the tubules, in a manner identical to inulin. PAH is different from inulin in that the fraction of PAH that bypasses the glomerulus and enters the nephron's tubular cells (via the peritubular capillaries) is completely secreted. Renal clearance of PAH is thus useful in calculation of renal plasma flow (RPF), which empirically is (1-hematocrit) times renal blood flow. Of note, the clearance of PAH is reflective only of RPF to portions of the kidney that deal with urine formation, and, thus, underestimates the actual RPF by about 10%.[38]

The measurement of GFR by inulin or sinistrin is still considered the

51Cr (chelated with EDTA), and creatinine, have had their utility confirmed in large cohorts of patients with chronic kidney disease.[citation needed
]

For both inulin and creatinine, the calculations involve concentrations in the urine and in the serum. However, unlike creatinine, inulin is not naturally present in the body. This is an advantage of inulin (because the amount infused will be known) and a disadvantage (because an infusion is necessary).[citation needed]

Metabolism in vivo

Inulin is indigestible by the human

colon do bacteria metabolise inulin, with the release of significant quantities of carbon dioxide, hydrogen, and/or methane. Inulin-containing foods can be rather gassy, in particular for those unaccustomed to inulin, and these foods should be consumed in moderation at first.[citation needed
]

Inulin is a soluble fiber, one of three types of dietary fiber including

insoluble, and resistant starch. Soluble fiber dissolves in water to form a gelatinous material. Some soluble fibers may help lower blood cholesterol and glucose levels.[39]

Because normal

gut.[5]
Inulin passes through the
bacterial flora. This makes it similar to resistant starches and other fermentable carbohydrates.[citation needed
]

Some traditional diets contain over 20 g per day of inulin or fructo-oligosaccharides. The diet of the prehistoric hunter-forager in the Chihuahuan Desert has been estimated to include 135 g per day of inulin-type fructans.[40] Many foods naturally high in inulin or fructo-oligosaccharides, such as chicory, garlic, and leek, have been seen as "stimulants of good health" for centuries.[41]

As of 2013, no regulatory authority had permitted health claims in the marketing of prebiotics as a class. Inulin's health effects had been studied in small clinical trials, which showed that it causes gastrointestinal adverse effects such as bloating and flatulence, does not affect

fatty liver, may help prevent travelers' diarrhea, and may help increase calcium absorption in adolescents.[18]

Natural sources

Plants that contain high concentrations of inulin include:

References

  1. ^
    PMID 15877886
    .
  2. PMID 17951492
    .
  3. ^ a b "The Declaration of Certain Isolated or Synthetic Non-Digestible Carbohydrates as Dietary Fiber on Nutrition and Supplement Facts Labels: Guidance for Industry" (PDF). US Food and Drug Administration. 14 June 2018. Retrieved 15 June 2018.
  4. PMID 21784836
    .
  5. ^
    PMID 10395607
    .
  6. ^
    S2CID 84555786
    .
  7. ^
    PMID 11285681
    .
  8. ^
    doi:10.1039/CT9201701489
    .
  9. doi:10.1021/ja01382a035
    .
  10. ^
    S2CID 87153900
    .
  11. PMID 16694313
    .
  12. PMID 6842964
    .
  13. ^ Barclay, Thomas, et al. Inulin – a versatile polysaccharide with multiple pharmaceutical and food chemical uses. Diss. International Pharmaceutical Excipients Council, 2010.
  14. PMID 12088531
    .
  15. ^ "What is Inulin? The Ultimate FAQ Guide to Inulin". Supplement Place. May 15, 2019. Retrieved 5 November 2022.
  16. ^ Rulis, Alan M. (5 May 2003). "Agency Response Letter GRAS Notice No. GRN 000118". US Food and Drug Administration.
  17. ^ Keefe, Dennis M. (9 December 2015). "Agency Response Letter GRAS Notice No. GRN 000576". US Food and Drug Administration.
  18. ^
    PMID 23609775
    .
  19. PMID 10395615
    .
  20. ^ "Caloric Value of Inulin and Oligofructose"[permanent dead link].
  21. PMID 16087995
    .
  22. PMID 12514257
    .
  23. doi:10.1016/s0271-5317(03)00085-x
    .
  24. PMID 26690475
    .
  25. PMID 21423403
    .
  26. PMID 12570825
    .
  27. ^
    S2CID 13767136
    .
  28. ^ Nosek, Thomas M. "Section 7, Chapter 4, Glomerular Filtration Rate". Essentials of Human Physiology. Archived from the original on 2016-03-24.
  29. ISBN 978-0-323-04883-5
    , retrieved 2022-02-11
  30. OCLC 396722036
    .
  31. PMID 20389058
    .
  32. PMID 10395609
    .
  33. S2CID 253266833
    .
  34. S2CID 25741852
    .
  35. PMID 8481000
    .
  36. ^
    ISBN 978-1-4200-4496-6
    .
  37. ^
    ISBN 978-3-642-14836-1
    .
  38. ^ Costanzo, Linda. Physiology, 4th Edition. Philadelphia: Lippincott Williams and Wilkins, 2007. Pages 156–160.
  39. PMID 27863994
    .
  40. PMID 20416127
    .
  41. PMID 10395609
    .
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