Inositol or cyclohexane-1,2,3,4,5,6-hexol is a chemical compound with formula C6H12O6 or (-CHOH-)6, a derivative of cyclohexane with six hydroxyl groups, making it a polyol (multiple alcohol). It exists in nine possible stereoisomers, of which cis-1,2,3,5-trans-4,6-cyclohexanehexol, or myo-inositol (former names meso-inositol or i-inositol), is the most widely occurring form in nature. Inositol is a sugar alcohol with half the sweetness of sucrose (table sugar).
cis-1,2,3,5-trans-4,6-Cyclohexanehexol , Cyclohexanehexol,
Mouse antialopecia factor,
Rat antispectacled eye
factor, and Scyllite
(for the structural
3D model (JSmol)
|Molar mass||180.16 g/mol|
|Melting point||225 to 227 °C (437 to 441 °F; 498 to 500 K)|
|Flash point||143 °C (289 °F; 416 K)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Myo-Inositol plays an important role as the structural basis for a number of secondary messengers in eukaryotic cells, the various inositol phosphates. In addition, inositol serves as an important component of the structural lipids phosphatidylinositol (PI) and its various phosphates, the phosphatidylinositol phosphate (PIP) lipids.
Inositol or its phosphates and associated lipids are found in many foods, in particular fruit, especially cantaloupe and oranges. In plants, the hexaphosphate of inositol, phytic acid or its salts, the phytates, serve as phosphate stores in seed, for example in nuts and beans. Phytic acid also occurs in cereals with high bran content. Phytate is, however, not directly bioavailable to humans in the diet, since it is not digestible. Some food preparation techniques partly break down phytates to change this. However, inositol in the form of glycerophospholipids, as found in certain plant-derived substances such as lecithins is well-absorbed and relatively bioavailable.
Myo-inositol (free of phosphate) was once considered a member of the vitamin B complex, called Vitamin B8 in this context. However, because it is produced by the human body from glucose, it is not an essential nutrient.
Isomers and structureEdit
The isomer myo-inositol is a meso compound, and hence optically inactive, because it has a plane of symmetry. For this reason, meso-inositol is an obsolete name for this compound. Besides myo-inositol, the other naturally occurring stereoisomers are scyllo-, muco-, D-chiro-, and neo-inositol, although they occur in minimal quantities in nature. The other possible isomers are L-chiro-, allo-, epi-, and cis-inositol. As their names denote, L- and D-chiro inositol are the only pair of inositol enantiomers, but they are enantiomers of each other, not of myo-inositol.
In its most stable conformation, the myo-inositol isomer assumes the chair conformation, which moves the maximum number of hydroxyls to the equatorial position, where they are farthest apart from each other. In this conformation, the natural myo isomer has a structure in which five of the six hydroxyls (the first, third, fourth, fifth, and sixth) are equatorial, whereas the second hydroxyl group is axial.
Myo-Inositol is synthesized from glucose-6-phosphate (G-6-P) in two steps. First, G-6-P is isomerised by an inositol-3-phosphate synthase enzyme (for example, ISYNA1) to myo-inositol 1-phosphate, which is then dephosphorylated by an inositol monophosphatase enzyme (for example, IMPA1) to give free myo-inositol. In humans, most inositol is synthesized in the kidneys, typically in amounts of a few grams per day.
Inositol, phosphatidylinositol and some of their mono- and polyphosphates function as secondary messengers in a number of intracellular signal transduction pathways. They are involved in a number of biological processes, including:
- Insulin signal transduction
- Cytoskeleton assembly
- Nerve guidance (epsin)
- Intracellular calcium (Ca2+) concentration control
- Cell membrane potential maintenance
- Breakdown of fats 
- Gene expression
In one important family of pathways, phosphatidylinositol 4,5-bisphosphate (PIP2) is stored in cellular membranes until it is released by any of a number of signalling proteins and transformed into various secondary messengers, for example diacylglycerol and inositol triphosphate.
Phytic acid in plantsEdit
Inositolhexaphosphate, also called phytic acid or IP6, is the principal storage form of phosphorus in many plant tissues, especially bran and seed. Phosphorus and inositol in phytate form are not generally bioavailable to nonruminant animals because these animals lack the digestive enzyme phytase required to remove the phosphate groups. Ruminants are readily able to digest phytate because of the phytase produced by rumen microorganisms. Moreover, phytic acid also chelates important minerals such as calcium, magnesium, iron, and zinc, making them unabsorbable, and contributing to mineral deficiencies in people whose diets rely highly on bran and seeds for their mineral intake, such as occurs in developing countries.
Inositol penta- (IP5), tetra- (IP4), and triphosphate (IP3) are also called "phytates".
Use in explosives manufactureEdit
At the 1936 meeting of the American Chemical Society, professor Edward Bartow of the University of Iowa presented a commercially viable means of extracting large amounts of inositol from the phytic acid naturally present in waste corn. As a possible use for the chemical, he suggested 'inositol nitrate' as a more stable alternative to nitroglycerin. Today, inositol nitrate is used to gelatinize nitrocellulose, thus can be found in many modern explosives and solid rocket propellants.
Counter to road saltEdit
When plants are exposed to increasing concentrations of road salt, the plant cells become dysfunctional and undergo apoptosis, leading to inhibited growth. Inositol pretreatment could reverse these effects.
Research and clinical applicationsEdit
Large doses of inositol have been studied for treatment of depression, but insufficient evidence exists to determine whether this is an effective treatment.
Inositol is considered a safe and effective treatment for polycystic ovary syndrome (PCOS). It works by increasing insulin sensitivity, which helps to improve ovarian function and reduce hyperandrogenism. It is also shown to reduce the risk of metabolic disease in people with PCOS.
Use as a cutting agentEdit
Inositol has been used as an adulterant or cutting agent for many illegal drugs, such as cocaine, methamphetamine, and sometimes heroin, probably because of its solubility, powdery texture, or reduced sweetness (50%) compared to more common sugars.
Inositol is also used as a stand-in for cocaine in television shows and in film.
Myo-Inositol is naturally present in a variety of foods, although tables of food composition do not always distinguish between lecithin, the bioavailable form, and the unavailable phytate form in grains. Foods containing the highest concentrations of myo-inositol (including its compounds) include fruits, beans, grains, and nuts. Beans and grains, however, contain large amounts of phytate.
- Merck Index, 11th Edition, 4883.
- Synonyms in PubChem
- Synonyms in Commonchemistry.org
- Clements RS, Darnell B (1980). "Myo-inositol content of common foods: development of a high-myo-inositol diet". The American Journal of Clinical Nutrition. 33 (9): 1954–67. PMID 7416064.
- "Phytic acid". www.phytochemicals.info. Retrieved 2017-10-02.
- Reynolds, James E. F. (January 1, 1993). Martindale: The Extra Pharmacopoeia. 30. Pennsylvania: Rittenhouse Book Distributors. p. 1379. ISBN 0-85369-300-5.
An isomer of glucose that has traditionally been considered to be a B vitamin although it has an uncertain status as a vitamin and a deficiency syndrome has not been identified in man
- Majumder, A. Lahiri; Biswas, B. B. (2006-10-03). Biology of Inositols and Phosphoinositides. Springer Science & Business Media. ISBN 9780387276007.
- Brady, Scott; Siegel, George; Albers, R. Wayne; Price, Donald (2005-11-11). Basic Neurochemistry: Molecular, Cellular and Medical Aspects. Academic Press. p. 348. ISBN 9780080472072.
- Parthasarathy LK, Seelan RS, Tobias C, Casanova MF, Parthasarathy RN (2006). "Mammalian inositol 3-phosphate synthase: its role in the biosynthesis of brain inositol and its clinical use as a psychoactive agent". Sub-cellular Biochemistry. 39: 293–314. PMID 17121280.
- Larner J (2002). "D-chiro-inositol—its functional role in insulin action and its deficit in insulin resistance". International Journal of Experimental Diabetes Research. 3 (1): 47–60. doi:10.1080/15604280212528. PMC . PMID 11900279.
- Gerasimenko JV, Flowerdew SE, Voronina SG, Sukhomlin TK, Tepikin AV, Petersen OH, Gerasimenko OV (2006). "Bile acids induce Ca2+ release from both the endoplasmic reticulum and acidic intracellular calcium stores through activation of inositol trisphosphate receptors and ryanodine receptors". The Journal of Biological Chemistry. 281 (52): 40154–63. doi:10.1074/jbc.M606402200. PMID 17074764.
- Kukuljan M, Vergara L, Stojilkovic SS (1997). "Modulation of the kinetics of inositol 1,4,5-trisphosphate-induced [Ca2+]i oscillations by calcium entry in pituitary gonadotrophs". Biophysical Journal. 72 (2 Pt 1): 698–707. Bibcode:1997BpJ....72..698K. doi:10.1016/S0006-3495(97)78706-X. PMC . PMID 9017197.
- Rapiejko PJ, Northup JK, Evans T, Brown JE, Malbon CC (1986). "G-proteins of fat-cells. Role in hormonal regulation of intracellular inositol 1,4,5-trisphosphate". The Biochemical Journal. 240 (1): 35–40. PMC . PMID 3103610.
- Shen X, Xiao H, Ranallo R, Wu WH, Wu C (2003). "Modulation of ATP-dependent chromatin-remodeling complexes by inositol polyphosphates". Science. 299 (5603): 112–4. doi:10.1126/science.1078068. PMID 12434013.
- Steger DJ, Haswell ES, Miller AL, Wente SR, O'Shea EK (2003). "Regulation of chromatin remodeling by inositol polyphosphates". Science. 299 (5603): 114–6. doi:10.1126/science.1078062. PMC . PMID 12434012.
- 1937–, Mathews, Christopher K., (2000). Biochemistry. Van Holde, K. E. (Kensal Edward), 1928–, Ahern, Kevin G. (3rd ed.). San Francisco, Calif.: Benjamin Cummings. p. 855. ISBN 0805330666. OCLC 42290721.
- Phytic acid
- Klopfenstein, Terry J.; Angel, Rosalina; Cromwell, Gary; Erickson, Galen E.; Fox, Danny G.; Parsons, Carl; Satter, Larry D.; Sutton, Alan L.; Baker, David H. (July 2002). "Animal Diet Modification to Decrease the Potential for Nitrogen and Phosphorus Pollution". Council for Agricultural Science and Technology. 21.
- Hurrell RF (2003). "Influence of vegetable protein sources on trace element and mineral bioavailability". The Journal of Nutrition. 133 (9): 2973S–7S. PMID 12949395.
- Committee on Food Protection; Food and Nutrition Board; National Research Council (1973). "Phytates". Toxicants Occurring Naturally in Foods. National Academy of Sciences. pp. 363–371. ISBN 978-0-309-02117-3.
- Laurence, William L. "Corn by-product yields explosive", The New York Times. April 17, 1936. Page 7.
- Ledgard, Jared. The Preparatory Manual of Explosives, 2007. p. 366.
- Chatterjee J, Majumder AL (2010). "Salt-induced abnormalities on root tip mitotic cells of Allium cepa: prevention by inositol pretreatment". Protoplasma. 245 (1–4): 165–72. doi:10.1007/s00709-010-0170-4. PMID 20559853.
- Theerakulp, P.; Gunnula, W. (2012). "Exogenous Sorbitol and Trehalose Mitigated Salt Stress Damage in Salt-sensitive but not Salt-tolerant Rice Seedlings". Asian Journal of Crop Science. 4 (4): 165–70. doi:10.3923/ajcs.2012.165.170.
- Taylor MJ, Wilder H, Bhagwagar Z, Geddes J (2004). "Inositol for depressive disorders". The Cochrane Database of Systematic Reviews (2): CD004049. doi:10.1002/14651858.CD004049.pub2. PMID 15106232.
- Howlett A, Ohlsson A, Plakkal N (2015). "Inositol in preterm infants at risk for or having respiratory distress syndrome". The Cochrane Database of Systematic Reviews (2): CD000366. doi:10.1002/14651858.CD000366.pub3. PMID 25927089.
- Monastra G, Unfer V, Harrath AH, Bizzarri M (2017). "Combining treatment with myo-inositol and D-chiro-inositol (40:1) is effective in restoring ovary function and metabolic balance in PCOS patients". Gynecological Endocrinology. 33 (1): 1–9. doi:10.1080/09513590.2016.1247797. PMID 27898267.
- Nordio M, Proietti E (2012). "The combined therapy with myo-inositol and D-chiro-inositol reduces the risk of metabolic disease in PCOS overweight patients compared to myo-inositol supplementation alone". European Review for Medical and Pharmacological Sciences. 16 (5): 575–81. PMID 22774396.
- http://feedadditivechina.com/6-16-inositol.html[full citation needed]
- Golianopoulos, Thomas. "Drug Doubles: What Actors Actually Toke, Smoke and Snort on Camera". Wired Magazine. Retrieved 14 May 2012.
|Wikimedia Commons has media related to Inositol.|