Phytic acid explained

Phytic acid is a six-fold dihydrogenphosphate ester of inositol (specifically, of the myo isomer), also called inositol hexaphosphate, inositol hexakisphosphate (IP6) or inositol polyphosphate. At physiological pH, the phosphates are partially ionized, resulting in the phytate anion.

The (myo) phytate anion is a colorless species that has significant nutritional role as the principal storage form of phosphorus in many plant tissues, especially bran and seeds. It is also present in many legumes, cereals, and grains. Phytic acid and phytate have a strong binding affinity to the dietary minerals calcium, iron, and zinc, inhibiting their absorption in the small intestine.[1]

The lower inositol polyphosphates are inositol esters with less than six phosphates, such as inositol penta- (IP5), tetra- (IP4), and triphosphate (IP3). These occur in nature as catabolites of phytic acid.

Significance in agriculture

Phytic acid was discovered in 1903.[2]

Generally, phosphorus and inositol in phytate form are not bioavailable to non-ruminant animals because these animals lack the enzyme phytase required to hydrolyze the inositol-phosphate linkages. Ruminants are able to digest phytate because of the phytase produced by rumen microorganisms.[3]

In most commercial agriculture, non-ruminant livestock, such as swine, fowl, and fish,[4] are fed mainly grains, such as maize, legumes, and soybeans.[5] Because phytate from these grains and beans is unavailable for absorption, the unabsorbed phytate passes through the gastrointestinal tract, elevating the amount of phosphorus in the manure. Excess phosphorus excretion can lead to environmental problems, such as eutrophication.[6] The use of sprouted grains may reduce the quantity of phytic acids in feed, with no significant reduction of nutritional value.[7]

Also, viable low-phytic acid mutant lines have been developed in several crop species in which the seeds have drastically reduced levels of phytic acid and concomitant increases in inorganic phosphorus.[8] However, germination problems have reportedly hindered the use of these cultivars thus far. This may be due to phytic acid's critical role in both phosphorus and metal ion storage. Phytate variants also have the potential to be used in soil remediation, to immobilize uranium, nickel, and other inorganic contaminants.[9]

Biological effects

Plants

Although indigestible for many animals as they occur in seeds and grains, phytic acid and its metabolites have several important roles for the seedling plant.

Most notably, phytic acid functions as a phosphorus store, as an energy store, as a source of cations and as a source of myo-inositol (a cell wall precursor). Phytic acid is the principal storage form of phosphorus in plant seeds.[10]

In vitro

In animal cells, myo-inositol polyphosphates are ubiquitous, and phytic acid (myo-inositol hexakisphosphate) is the most abundant, with its concentration ranging from 10 to 100 μM in mammalian cells, depending on cell type and developmental stage.[11] [12]

Phytic acid is not obtained from the animal diet, but must be synthesized inside the cell from phosphate and inositol (which in turn is produced from glucose, usually in the kidneys). The interaction of intracellular phytic acid with specific intracellular proteins has been investigated in vitro, and these interactions have been found to result in the inhibition or potentiation of the activities of those proteins.[13] [14]

Inositol hexaphosphate facilitates the formation of the six-helix bundle and assembly of the immature HIV-1 Gag lattice. IP6 makes ionic contacts with two rings of lysine residues at the centre of the Gag hexamer. Proteolytic cleavage then unmasks an alternative binding site, where IP6 interaction promotes the assembly of the mature capsid lattice. These studies identify IP6 as a naturally occurring small molecule that promotes both assembly and maturation of HIV-1.[15]

Dentistry

IP6 has potential use in endodontics, adhesive, preventive, and regenerative dentistry, and in improving the characteristics and performance of dental materials.[16] [17] [18]

Food science

Phytic acid, mostly as phytate in the form of phytin, is found within the hulls and kernels of seeds,[19] including nuts, grains, and pulses.[1]

In-home food preparation techniques may break down the phytic acid in all of these foods. Simply cooking the food will reduce the phytic acid to some degree. More effective methods are soaking in an acid medium, sprouting, and lactic acid fermentation such as in sourdough and pickling. [20]

No detectable phytate (less than 0.02% of wet weight) was observed in vegetables such as scallion and cabbage leaves or in fruits such as apples, oranges, bananas, or pears.[21]

As a food additive, phytic acid is used as the preservative E391.[22] [23]

Food! colspan=2
Proportion by weight (g/100 g)
Hulled Hemp Seed4.54.5
4.3 4.3
2.15 2.78
Sesame seeds flour 5.36 5.36
0.96 1.16
1.35 3.22
Brazil nuts 1.97 6.34
0.36 0.36
0.65 0.65
0.95 1.76
0.98 0.98
Maize (corn) 0.75 2.22
0.42 1.16
Oat meal 0.89 2.40
0.84 0.99
0.14 0.60
0.39 1.35
0.25 1.37
0.08 1.14
0.43 1.05
2.38 2.38
1.00 1.00
0.56 0.56
0.44 0.50
1.00 2.22
1.46 2.90
Soy beverage 1.24 1.24
Soy protein concentrate 1.24 2.17
0.18 0.34
0.22 NR
0.51 0.51
Chestnuts[24] 0.47
1.60
Food! colspan=2
Proportion by weight (%)
0.143 0.195
0.114 0.152

Dietary mineral absorption

Phytic acid has a strong affinity to the dietary trace elements, calcium, iron, and zinc, inhibiting their absorption from the small intestine.[1] [25] Phytochemicals such as polyphenols and tannins also influence the binding.[26] When iron and zinc bind to phytic acid, they form insoluble precipitates and are far less absorbable in the intestines.[27] [28]

Because phytic acid also can affect the absorption of iron, "dephytinization should be considered as a major strategy to improve iron nutrition during the weaning period".[29] Dephytinization by exogenous phytase to phytate-containing food is an approach being investigated to improve nutritional health in populations that are vulnerable to mineral deficiency due to their reliance on phytate-laden food staples. Crop breeding to increase mineral density (biofortification) or reducing phytate content are under preliminary research.[30]

See also

Notes and References

  1. Schlemmer. U.. Frølich. W.. Prieto. R. M.. Grases. F.. 2009. Phytate in foods and significance for humans: Food sources, intake, processing, bioavailability, protective role and analysis. Molecular Nutrition & Food Research. 53. Suppl 2 . S330–75. 10.1002/mnfr.200900099. 19774556.
  2. Web site: Mullaney. Edward J. . vanc . Phytases: attributes, catalytic mechanisms, and applications. United States Department of Agriculture–Agricultural Research Service. May 18, 2012. Ullah, Abul H.J.. https://web.archive.org/web/20121107115333/http://www.stri.si.edu/sites/inositol_conference/program/PDFs/monday_morning/Mullaney.pdf. 2012-11-07. dead.
  3. Terry J. . Klopfenstein . Rosalina . Angel . Gary . Cromwell . Galen E. . Erickson . Danny G. . Fox . Carl . Parsons . Larry D. . Satter . Alan L. . Sutton . David H. . Baker . vanc . July 2002 . Animal Diet Modification to Decrease the Potential for Nitrogen and Phosphorus Pollution . Council for Agricultural Science and Technology . 21 .
  4. Romarheim OH, Zhang C, Penn M, Liu YJ, Tian LX, Skrede A, Krogdahl Å, Storebakken T . 2008 . Aquaculture Nutrition. Growth and intestinal morphology in cobia (Rachycentron canadum) fed extruded diets with two types of soybean meal partly replacing fish meal . 14 . 2 . 174–180 . 10.1111/j.1365-2095.2007.00517.x.
  5. Jezierny. D.. Mosenthin. R.. Weiss. E.. 2010-05-01. The use of grain legumes as a protein source in pig nutrition: A review. Animal Feed Science and Technology . 157. 3–4. 111–128. 10.1016/j.anifeedsci.2010.03.001.
  6. 10.1023/A:1023690824045 . 27503850. 2003 . Industrialized Animal Production—A Major Source of Nutrient and Microbial Pollution to Aquatic Ecosystems. Mallin MA . Population and Environment. 24. 5. 369–385. 154321894.
  7. 10.1007/BF01092036 . Nutritive value of malted millet flours . 1986 . Malleshi . N. G. . Plant Foods for Human Nutrition . 36 . 191–6 . Desikachar . H. S. R.. 3.
  8. Guttieri MJ, Peterson KM, Souza EJ . 10.2135/cropsci2006.03.0137 . Milling and Baking Quality of Low Phytic Acid Wheat . Crop Science . 46 . 2403–8. 6. 2006 . 33700393 .
  9. Seaman JC, Hutchison JM, Jackson BP, Vulava VM . In situ treatment of metals in contaminated soils with phytate . Journal of Environmental Quality . 32 . 1 . 153–61 . 2003 . 12549554 . 10.2134/jeq2003.0153 .
  10. Book: Advances in Food Research . Reddy NR, Sathe SK, Salunkhe DK . 1982 . 9780120164288 . Advances in Food Research . 28 . 1–92 . Phytates in legumes and cereals . 10.1016/s0065-2628(08)60110-x . 6299067.
  11. Szwergold BS, Graham RA, Brown TR . Observation of inositol pentakis- and hexakis-phosphates in mammalian tissues by 31P NMR . Biochemical and Biophysical Research Communications . 149 . 3 . 874–81 . December 1987 . 3426614 . 10.1016/0006-291X(87)90489-X .
  12. Sasakawa N, Sharif M, Hanley MR . Metabolism and biological activities of inositol pentakisphosphate and inositol hexakisphosphate . Biochemical Pharmacology . 50 . 2 . 137–46 . July 1995 . 7543266 . 10.1016/0006-2952(95)00059-9 .
  13. Hanakahi LA, Bartlet-Jones M, Chappell C, Pappin D, West SC . Binding of inositol phosphate to DNA-PK and stimulation of double-strand break repair . Cell . 102 . 6 . 721–9 . September 2000 . 11030616 . 10.1016/S0092-8674(00)00061-1 . 112839 . free .
  14. Norris FA, Ungewickell E, Majerus PW . Inositol hexakisphosphate binds to clathrin assembly protein 3 (AP-3/AP180) and inhibits clathrin cage assembly in vitro . The Journal of Biological Chemistry . 270 . 1 . 214–7 . January 1995 . 7814377 . 10.1074/jbc.270.1.214 . free .
  15. Dick RA, Zadrozny KK, Xu C, Schur FK, Lyddon TD, Ricana CL, Wagner JM, Perilla JR, Ganser-Pornillos BK, Johnson MC, Pornillos O, Vogt VM . Inositol phosphates are assembly co-factors for HIV-1 . Nature . 560 . 7719 . 509–512 . August 2018 . 30069050 . 10.1038/s41586-018-0396-4 . 6242333 . 2018Natur.560..509D .
  16. 10.3389/fmats.2021.638909. free. Phytic Acid: Properties and Potential Applications in Dentistry. 2021. Nassar. Mohannad. Nassar. Rania. Maki. Husain. Al-Yagoob. Abdullah. Hachim. Mahmood. Senok. Abiola. Williams. David. Hiraishi. Noriko. Frontiers in Materials. 8. 29. 2021FrMat...8...29N.
  17. Nassar M, Nassar R, Maki H, Al-Yagoob A, Hachim M, Senok A, Williams D, Hiraishi N . Phytic Acid: Properties and Potential Applications in Dentistry . Frontiers in Materials . March 2021 . 8 . 29 . 10.3389/fmats.2021.638909 . 2021FrMat...8...29N . free .
  18. Nassar. Rania. Nassar. Mohannad. Vianna. Morgana E.. Naidoo. Nerissa. Alqutami. Fatma. Kaklamanos. Eleftherios G.. Senok. Abiola. Williams. David. 2021. Antimicrobial Activity of Phytic Acid: An Emerging Agent in Endodontics. Frontiers in Cellular and Infection Microbiology. 11. 753649. 10.3389/fcimb.2021.753649. 34765567. 8576384. 2235-2988. free.
  19. Ellison. Campbell. Moreno. Teresa. Catchpole. Owen. Fenton. Tina. Lagutin. Kirill. MacKenzie. Andrew. Mitchell. Kevin. Scott. Dawn. 2021-07-01. Extraction of hemp seed using near-critical CO2, propane and dimethyl ether. The Journal of Supercritical Fluids. en. 173. 105218. 10.1016/j.supflu.2021.105218. 233822572. 0896-8446.
  20. Web site: Phytates in cereals and legumes . . 1989 . agris.fao.org . CRC Press . https://web.archive.org/web/20230419153827/http://agris.fao.org/agris-search/search.do?recordID=US9032841 . 2023-04-19 . dead.
  21. Phillippy BQ, Wyatt CJ . Degradation of phytate in foods by phytases in fruit and vegetable extracts. . Journal of Food Science . May 2001 . 66 . 4 . 535–539 . 10.1111/j.1365-2621.2001.tb04598.x .
  22. Functional Food - Improve Health through Adequate Food edited by María Chávarri Hueda, pg. 86
  23. Web site: Wise Eating, Made Easy.
  24. Web site: Paleo Diet Guide: With Recipes in 30 Minutes or Less: Diabetes Heart Disease: Paleo Diet Friendly: Dairy Gluten Nut Soy Free Cookbook. Markus. Scuhlz . vanc . PWPH Publications. Google Books.
  25. 4325021. 2013. Gupta. R. K.. Reduction of phytic acid and enhancement of bioavailable micronutrients in food grains. Journal of Food Science and Technology. 52. 2. 676–684. Gangoliya. S. S.. Singh. N. K.. 25694676. 10.1007/s13197-013-0978-y.
  26. Prom-u-thai C, Huang L, Glahn RP, Welch RM, Fukai S, Rerkasem B . 10.1002/jsfa.2471 . Iron (Fe) bioavailability and the distribution of anti-Fe nutrition biochemicals in the unpolished, polished grain and bran fraction of five rice genotypes . Journal of the Science of Food and Agriculture . 2006 . 86 . 1209–15 . 8 . 2006JSFA...86.1209P . 2018-12-29 . 2020-02-23 . https://web.archive.org/web/20200223165420/https://naldc-legacy.nal.usda.gov/naldc/download.xhtml?id=19315&content=PDF . dead .
  27. Hurrell RF . Influence of vegetable protein sources on trace element and mineral bioavailability . The Journal of Nutrition . 133 . 9 . 2973S–7S . September 2003 . 12949395 . 10.1093/jn/133.9.2973S . free .
  28. Book: Phytates . Toxicants Occurring Naturally in Foods . Committee on Food Protection . Food and Nutrition Board . National Research Council . National Academy of Sciences . 1973 . 978-0-309-02117-3 . 363–371 . https://books.google.com/books?id=lIsrAAAAYAAJ&pg=PA363 .
  29. Hurrell RF, Reddy MB, Juillerat MA, Cook JD . Degradation of phytic acid in cereal porridges improves iron absorption by human subjects . The American Journal of Clinical Nutrition . 77 . 5 . 1213–9 . May 2003 . 12716674 . 10.1093/ajcn/77.5.1213 . 10.1.1.333.4941 .
  30. Raboy . Victor . Low phytic acid crops: Observations based on four decades of research . Plants . 9 . 2 . 22 January 2020 . 2223-7747 . 31979164 . 10.3390/plants9020140 . 140. 7076677 . free .

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Phytic acid".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.