Allicin

Chembox new
Name = Allicin
ImageFile = R-allicin-2D-skeletal.png ImageSize = 250px
ImageName = Allicin
ImageFile1 = R-alllicin-3D-balls.png ImageSize1 = 220px
ImageName1 = S-allicin
IUPACName = 2-propene-1-sulfinothioic acid S-2-propenyl ester
Section1 = Chembox Identifiers
CASNo = 539-86-6
pubchem = 65036
CID = 65036
SMILES = C=CCS(=O)SCC=C
Section2 = Chembox Properties
Formula = C₆H₁₀OS₂
MolarMass = 162.28 g/mol
Density = 1.112 g/cm³
MeltingPt =<25 °C
BoilingPt = dec.

Allicin is an organic compound obtained from garlic. This colourless liquid has a distinctively pungent smell. This compound exhibits antibacterial and anti-fungal properties. [Chester J. Cavallito, John Hays Bailey "Allicin, the Antibacterial Principle of "Allium sativum". I. Isolation, Physical Properties and Antibacterial Action" Journal of the American Chemical Society, 1944, volume 66, pp 1950 - 1951. {DOI|10.1021/ja01239a048]

tructure and occurrence

Allicin is not present in garlic unless tissue damage occurs [cite journal | author=Eric Block | title= The chemistry of garlic and onions | journal=Scientific American | volume=252 | issue=March | year=1985 | pages=114-119] , and is formed by the action of the enzyme alliinase on alliin. [cite journal | author=Eric Block | title= The chemistry of garlic and onions | journal=Scientific American | volume=252 | issue=March | year=1985 | pages=114–119] It can also be prepared in racemic form by oxidation of diallyldisulfide: [R. J. Cremlyn “An Introduction to Organosulfur Chemistry” John Wiley and Sons: Chichester (1996). ISBN 0 471 95512 4.] :(SCH₂CH=CH₂)₂ + RCO₃H → CH₂=CHCH₂SS(O)CH₂CH=CH₂ + RCO₂H

Alliinase is irreversibly deactivated below a pH of 3; as such, allicin is generally not produced in the body from the consumption of fresh or powdered garlic. [Brodnitz, M.H. Pascale, J.V., and Derslice, L.V. Flavor components of garlic extract. J. Agr. Food. Chem. 19(2):273-275, 1971] [Yu. T-H, and Wu, C-M. Stability of allicin in garlic juice. J. Food Sci. 54(4): 977-981, 1989] Furthermore, allicin is unstable, degrading slowly upon standing at room temperature and rapidly with heat (e.g., by cooking).Fact|date=July 2008

Potential health benefits

Several animal studies published between 1995 and 2005 indicate that allicin may: reduce atherosclerosis and fat deposition. [cite journal | author= S. Eilat, Y. Oestraicher, A. Rabinkov, D. Ohad, D. Mirelman, A. Battler, M. Eldar and Z. Vered | title= Alteration of lipid profile in hyperlipidemic rabbits by allicin, an active constituent of garlic | journal= Coron. Artery Dis. | volume=6| year=1995| pages=985–990] [cite journal | author= D. Abramovitz, S. Gavri, D. Harats, H. Levkovitz, D. Mirelman, T. Miron, S. Eilat-Adar, A. Rabinkov, M. Wilchek, M. Eldar and Z. Vered, | title= Allicin-induced decrease in formation of fatty streaks (atherosclerosis) in mice fed a cholesterol-rich diet | journal= Coron. Artery Dis. | volume=10 | year=1999| pages=515–519 | doi= 10.1097/00019501-199910000-00012] , normalize the lipoprotein balance, decrease blood pressure [cite journal | author= Silagy CA, Neil HA | title= A meta-analysis of the effect of garlic on blood pressure | journal= J Hypertens | volume=12(4) | year=1994| pages=463-468 ] [cite journal | author= A. Elkayam, D. Mirelman, E. Peleg, M. Wilchek, T. Miron, A. Rabinkov, M. Oron-Herman and T. Rosenthal | title= The effects of allicin on weight in fructose-induced hyperinsulinemic, hyperlipidemic, hypertensive rats | journal= Am. J. Hypertens | volume=16 | year=2003| pages=1053–1056 | doi= 10.1016/j.amjhyper.2003.07.011] , have anti-thrombotic [cite journal | author= Srivastava KC | title= Evidence for the mechanism by which garlic inhibits platelet aggregation. | journal= Prostaglandins Leukot Med | volume=22(3) | year=1986 | pages=313-321 ] and anti-inflammatory activities, and function as an antioxidant to some extent [cite journal | author= U. Sela, S. Ganor, I. Hecht, A. Brill, T. Miron, A. Rabinkov, M. Wilchek, D. Mirelman, O. Lider and R. Hershkoviz | title= Allicin inhibits SDF-1alpha-induced T cell interactions with fibronectin and endothelial cells by down-regulating cytoskeleton rearrangement, Pyk-2 phosphorylation and VLA-4 expression | journal= Immunology | volume=111 | year=2004| pages=391–399 | doi= 10.1111/j.0019-2805.2004.01841.x] [cite journal | author=Lindsey J. Macpherson, Bernhard H. Geierstanger, Veena Viswanath, Michael Bandell, Samer R. Eid, SunWook Hwang, and Ardem Patapoutian | title= [http://www.current-biology.com/content/article/fulltext?uid=PIIS096098220500391X The pungency of garlic: Activation of TRPA1 and TRPV1 in response to allicin] | journal=Current Biology | volume=15 | issue=May 24 | year=2005 | pages=929–934] [cite journal | author=Bautista DM, Movahed P, Hinman A, Axelsson HE, Sterner O, Hogestatt ED, Julius D, Jordt SE and Zygmunt PM | title=Pungent products from garlic activate the sensory ion channel TRPA1| journal=Proc Natl Acad Sci U S A | volume=102 | issue=34 | year=2005 | pages=12248–52 | doi=10.1073/pnas.0505356102 | pmid=16103371] . Other studies have shown a strong oxidative effect in the gut that can damage intestinal cells. [Lawson, L. D., Ransom, D. K. and Hughes, B. G. Inhibition of whole blood platelet-aggregation by compounds in garlic clove extracts and commercial garlic products. Throm. Res. 65: 141-156, 1992.]

ee also

* Allyl isothiocyanate, the active piquant chemical in mustard, radishes, horseradish and wasabi
* Capsaicin, the active piquant chemical in chile peppers
* Piperine, the active piquant chemical in black pepper
* Syn-propanethial-S-oxide, the chemical found in onions
* List of phytochemicals in food

References

External links

* [http://pubs.acs.org/subscribe/journals/mdd/v05/i04/html/04news4.html Investigation of allicin use against superbugs, MRSA & VRE]
* [http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=10594976&dopt=AbstractPlus Antimicrobial properties of allicin from garlic]