Phytic acid myo-inositol

An equally simple chemical study was carried out on phytic acid-aluminosilicate cements (Prosser et al., 1983). Phytic acid, myo-inositol hexakis(dihydrogen phosphate), is a naturally occurring substance found in seeds, and it is a stronger acid than phosphoric acid. Cements were prepared using aqueous solutions of phytic acid, concentrated to 50 wt%, and with 5 wt % zinc dissolved in the acid to moderate the rate of reaction with the glass powder. Discs of cement were prepared and these were... 

In his Natural History (1826), Pliny the Elder stated that those persons who are dieted npon fermented bread are stronger in body , which is an early statement on the health benefits of sourdough breads. Whole meals of cereals are a good source of minerals. Their bioavailability is limited, as they are often bound to phytic acid (myo-inositol-hexophospate). Wheat and rye contain about 1.2% of dry matter (Fretzdorff Briimmer, 1992). With the drop in pH during sourdough fermentation, endogenous phytases of the cereals are activated and the bound minerals are released (Fretzdorff Briimmer, 1992). Lactic acid bacteria and yeasts also possess phytase... 

Phytic acid, myo-inositol hexakis (dIhydrogen phosphate), as-l,2,3,S-tnns-4,6-cyclohexanehexol-hexaphosphate a major phosphate storage compound in plants, which is especially abundant in oil seeds, legumes and cereal grains. It is the hexaphosphate of A/yo-inositol (see), in which each OH-group of myoinositol is esterified with phosphoric acid. Calcium and magnesium salts of P.a. are known as phytin. The commercial preparation of myo-inositol involves extraction of P. a. from com (maize) steep liquor, hydrolysis of the P.a. to myo-inositol and inorganic phosphate, and crystallization of the myo-inositol from water. 

Recently, the determination of phytic acid (myo-inositol hexaphosphate), which is believed to have an effect on the bioavailability of mineral substances, has become important. While phytic acid is not a food conshtuent in the United States, in other countries it is frequently added to foods as an anhoxidant [250,... 

Phytic acid (myo-inositol hexaphosphate) has been clearly established as a major phosphate reserve in many seeds, containing more than 50% of the total stored... 

Theoretical studies of the hydrolysis of methyl phosphate anion have found that the dissociative mechanism involving the formation of metaphosphate is favoured over the associative mechanism involving a pentacoordinated intermediate.Phytic acid, myo-inositol hexakis(dihydrogen phosphate) (127), was completely hydrolysed to inositol in an aqueous polybasic alcohol at 150 °C a reaction mechanism was proposed. The reactions of p-nitrophenyl diethyl phosphate (128) and ethyl p-niuophenyl ethylphosphonate (129) with a wide range of oximate ions (p/(a = 7-13) in 10% aqueous ethanol at 25 °C have been studied. For oximate ions with p a 9.0, the reactivity of the oximes tends towards that of alcoholate ions and their Q -effect disappears (as had been previously shown with / -niuophenyl acetate). The reason for this is the unfavourable solvation effects of the solvent. A review (253 references) has appeared on the synthesis and reaction of Q -aminophosphonates. ° ... 

Phytic acid (myo-inositol-l,2,3,4,5,6-hexakisdihydrogen phosphate) occurs in a number of important crops, especially cereals, legumes and oilseeds. The main form is a mixed calcium and magnesium salt, which is called phytin. Phytate phosphorus has reduced biological utihsation and lower utihsation than other minerals (Ca, Mg and Zn and Fe in particular). The contents of phytic acid in some food materials and foods, and the ratio of phytate phosphorus to total phosphorus, are shown in Table 6.5. 

Phytic acid,myo-inositol-l,2,3,4,5,6-hexakisdihydrogenphosphate, is the main storage form of phosphorus used during germination of seeds of cereals, pulses and oilseeds. Phytic add in seeds occurs primarily as a mixed calcium and magnesium salt, which is called phytin. Insoluble salts and ones that are utilised only slightly are also produced with other di- and trivalent ions, such as Fe and Zn in particular. The issue of phytin is discussed in detail in Chapter 6 (see Section 6.3.4.2.1). 

Phytate is used here collectively in reference to metal ion derivatives of inositol hexa- and pentakisphos-phates and includes all isomeric forms. As a purified compound, phytate is available as myo-inositol hexa-kis[dihydrogen] phosphate (a salt of phytic acid or inositol hexaphosphoric acid) and is commonly abbreviated as IHP or lnsP6. Throughout this chapter the term phytate is used for generic reference and myo-inositol hexakisphosphate in relation to the use of purified compound. 

Phytic acid (wyo-inositol hexaphosphate) can be desymmetrized using phopha-tases found in Bakers yeast which allows the isolation of D-myo-inositol 1,2,6-trisphosphate. This was further used to prepare 3,4,5-tri-O-phenylcarbamoyl d-wyo-inositol. ... 

Amongst the cyclic polyols, inositols are most widely distributed in the plant kingdom.234 Out of nine stereoisomers, myo-inositol has the most widespread metabolic significance.235 The derivatives of myoinositol are also widespread. In plants, myo-inositol plays an important role in the biosynthesis of hemicelluloses and oligosaccharides it also occurs as a storage product (phytic acid), a coenzyme for sugar-transport, a precursor of phosphoinositides, and esters of in-doleacetic acid.47,113,238... 

Hegeman, C.E., Good, L.L., and Grabau, E.A., 2001, Expression of D-myo-Inositol-3-phosphate synthase in soybean. Implications for phytic acid biosynthesis. Plant Physiol. 125 1941— 1948. 

Larson, S.R., and Raboy, V, 1999, Linkage mapping of maize and barley myo-inositol 1 -phosphate synthase DNA sequences Correspondence with a low phytic acid mutation. Theor. Appl. Genet. 99 27-36. 

A method is being developed to transform actinide ions in the near surface environment to less soluble, less reactive, thermodynamically stable phosphate minerals phases through application of organophosphorus complexants. These complexants decompose slowly, releasing phosphate to promote the formation of stable phosphate mineral phases, particularly with the more soluble trivalent, pentavalent, and hexavalent actinide ions. The complexant of choice, myo-inositol(hexakisphosphoric acid) or phytic acid, is a natural product widely used as a nutritional supplement. We have determined that phytic acid decomposes slowly in the absence of microbiological effects, that crystalline phosphate minerals are formed as a consequence of its decomposition, and that the formation of actinide (lanthanide) phosphates reduces the solubility of trivalent and hexavalent metal ions under environmental conditions. 

One very promising organophosphorus compound is the abundant, phosphate rich, natural product myo-inositol(hexakisphosphoric acid), or phytic acid. Literature reports on the chemical, environmental, and biological behavior of phytic acid abound 13), Phytic acid is isolated from beans and leafy vegetables and is used as the starting... 

Inositol (hexahydroxycyclohexane) occurs in several isomeric forms. Myo-inositol (or meso-inositol) is an important constituent of phospholipids and is the only isomer with biological activity. Inositol hexaphosphate (phytic acid) is found in avian erythrocytes, where it binds to hemoglobin, thereby regulating the oxygen capacity of the blood. It is also important as an intracellular messenger in a number of pathways. 

Katayama, T. Effects of dietary myo-inositol or phytic acid on hepatic concentrations of lipids and hepatic activities of lipogenic enzymes in rats fed on corn starch or sucrose. Nutr. Res., 1997, 17,... 

Molinari, E. Hoffmann-Ostenhof, O. Studies on the biosynthesis of cyclitols. XXI. An enzyme system capable of phosphorylating myo-inositol to phytic acid. Hoppe-Seyler s Z. Physiol. Chem., 349, 1797-1799 (1968)... 

Organic phosphorus compounds, primarily inositolhexaphosphates (probably more than 50% of all organic phosphates), occiu in soils. The parent cyclic polyol, inositol, exists in numerous stereoisomeric configurations, of which myo-, scyllo-, neo-, and cZZ-inositol have been isolated from soils as phosphate esters. The hexaphosphate of myoinositol (myo-IHP), phytic acid, occurs in plant tissues. It often occurs as phytin, the calcium magnesium salt. Esters of myo-IHP are readily adsorbed in acidic soil solution by clay minerals and finely divided hydrated oxides of iron and aluminum. Organic sulfur compounds present in soils probably occur primarily as amino acids—e.g., cysteine, cystine, and methionine. 

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