Talk:Tartaric acid

From Wikipedia, the free encyclopedia
Jump to: navigation, search

In 1854, Pasteur cultured a blue penicillin mold in a racemic tartaric acid solution and found that the mold metabolized only the right-handed D-tartaric acid, leaving the left-handed L-tartaric acid. Hence, dextrotartaric acid is the one that occurs in nature.

Muscle toxin[edit]

Tartaric acid is a muscle toxin, which works by inhibiting the production of malic acid, and in high doses causes paralysis and death. The minimum recorded fatal dose for a human is about 12 grams. In spite of that, it is included in many foods, especially sour-tasting sweets.

Precisely how much is in most food, though? That's a really important thing to note. If these sour sweets only have .1 microgram, and the stuff is metabolized, I don't think it's cause for concern...

I've never heard of anyone dying from a grape overdose. :) Mike Church 04:47, 1 May 2004 (UTC)

I found at least one MSDS sheet that reports that the LD50 for tartaric acid is undefined. Another seemed to suggest that you needed something like 500mg/kg injected intraveniously or intramuscular. Either way, the numbers are unrealistic. I recommend removing this line until someone can back it up better. "Minimum recorded" ... recorded where? --Mdwyer 23:22, 12 January 2006 (UTC)
Oh, and by the way, dogs can be killed by grape or raisin overdoses. The snopes page says they don't know what the actual toxic substance is, however. --Mdwyer

The article had Potassium tartrate linked as "Cream of Tartar", but when you went to that link it says that is is commonly mistaken for Potassium bitartrate, which claims to be the real Cream of Tartar. So, I have 'fixed' the link. --Mdwyer 02:32, 22 May 2006 (UTC)

From D-tartaric acid[edit]

Chemical Name :2S,3S-Dihydroxy Succinic acid Molecular Formula :C4H6O6 Molecular Weight : 150.09 Melting Point :171 deg C- 174 deg C STORAGE : Kept in a light-proof, well-closed, dry and cool place.

D-tartaric acid exists as a white cystalline powder under standard contitions. An important property is that two of its carbon atoms are chiral carbons. This means it is widely used in pharmaceuticals where specific optical isomers are required. It can be used to resolve amino acids quickly and easily.

structure : yet to be uploaded from [1]

For the main article on this topic see tartaric acid.

Ball and stick model[edit]

The ball & stick model at the top right should show hydrogen atoms, or at least it should show double bonds. There is, of course, a convention in which organic structures are drawn without showing hydrogen atoms, but then it is essential to show multiple bonds in order to figure out where the hydrogens go. That convention is not appropriate for chemistry novices anyway. Ball and stick models are often shown without indicating multiple bonds (displaying the skeleton of the molecule), but such models typically show ALL of the atoms. The ball & stick model as shown does not permit even a chemical expert to distinguish which oxygen atoms are carbonyl groups and which are part of hydroxyl groups. -Carmen Giunta, Professor of Chemistry, Le Moyne College

The ball and stick model did show double bonds but admittedly they were hard to see. I have changed the ball and stick model to the structural formula which is far easier to follow. Thanks for your input Carmen. Scharks 00:50, 5 March 2006 (UTC)

Tartaric acid in jam[edit]

Tartaric acid is an ingredient of jam. It would be nice to have an explanation as to why, ie, what does it do to the jam. Synique (talk) 02:16, 20 January 2008 (UTC)

WikiProject Food and drink Tagging[edit]

This article talk page was automatically added with {{WikiProject Food and drink}} banner as it falls under Category:Food or one of its subcategories. If you find this addition an error, Kindly undo the changes and update the inappropriate categories if needed. The bot was instructed to tagg these articles upon consenus from WikiProject Food and drink. You can find the related request for tagging here . Maximum and careful attention was done to avoid any wrongly tagging any categories , but mistakes may happen... If you have concerns , please inform on the project talk page -- TinucherianBot (talk) 01:14, 4 July 2008 (UTC)

article to fix missing citation[edit]

I've found an article confirming Jabir ibn Hayyan isolated tartaric acid. Could someone please add it?

Acta Crystallographica Section A Foundations of Crystallography Volume 64, Part 1 (January 2008)

Zygmunt S. Derewenda: On wine, chirality and crystallography

available freely at —Preceding unsigned comment added by (talk) 01:19, 16 October 2008 (UTC)

D and L naming convention[edit]

Tartaric acid illustrates the ambiguities that can sometimes arise in the D/L naming convention, which is based on a molecule's presumed "genealogy" or sequence of chemical transformations by which the molecule might be made from D or L glyceraldehyde. As Prof. McBride points out in his lecture on the subject [2], two genealogies may produce opposite results. As it turned out, the genealogy historically adopted for tartaric acid gave the natural form the L designation, even though the configuration appears more similar to D-glyceraldehyde (that is, if one makes the replacements CHO -> COOH, and CH2OH -> CHOH-COOH). Thus the Fischer and Ball-and-stick structures given in the article are correct, and the names reflect historical usage, with the natural form being dextrorotatory and designated L(+), as I have verified from several sources, even though its structure may look more similar to D- than to L-glyceraldehyde.CharlesHBennett (talk) 01:06, 2 December 2010 (UTC)CharlesHBennett (talk) 01:12, 2 December 2010 (UTC)

Enantiomerism and molecular symmetry[edit]

I am facing heavy confusion with enantiomerism in this kind of molecule. I believe of course that D- and L-tartaric acid exist. However, I am unable to wrap my head around how. Whatever I do, building molecular models, imagining etc. I am always able to simply take the L-form, rotate it by 180° and as a result get the D-form; meaning that these two are not actually different molecules. On paper this is possible, because C1 and C4 in fact are the same groups and so allow simply "flipping" the fisher notation along a horizontal axis.

The only stereoisomerism that actually results in different molecules seems to be "both OH groups on the same side" and "OH groups on different sides". How can the D- and L-forms still be enantiomers and have such different properties? Or rather, does anybody have an idea where I'm thinking wrong? Thank you very much :) - Be bbes (talk) 18:54, 5 January 2012 (UTC)

Please ignore, I found the issue. I was mistaking the Fisher projection, imagining the third vertical bond coming out of the printed plane rather than going backwards behind the plane. That meant one chiral atom as I imagined it was the wrong way around, causing what I saw as the D- and L-forms to actually be the meso form. - Be bbes (talk) 20:47, 6 January 2012 (UTC)

File:Brechweinstein.jpg Nominated for Deletion[edit]

Image-x-generic.svg An image used in this article, File:Brechweinstein.jpg, has been nominated for deletion at Wikimedia Commons in the following category: Deletion requests March 2012
What should I do?

Don't panic; a discussion will now take place over on Commons about whether to remove the file. This gives you an opportunity to contest the deletion, although please review Commons guidelines before doing so.

  • If the image is non-free then you may need to upload it to Wikipedia (Commons does not allow fair use)
  • If the image isn't freely licensed and there is no fair use rationale then it cannot be uploaded or used.

To take part in any discussion, or to review a more detailed deletion rationale please visit the relevant image page (File:Brechweinstein.jpg)

This is Bot placed notification, another user has nominated/tagged the image --CommonsNotificationBot (talk) 19:55, 19 March 2012 (UTC)

Error in Stereochemistry section and "Forms of Tartaric Acid" table?[edit]

I fail to understand why, in both the table and the stereochemistry section, D-(S,S)-(−)-tartaric acid is referred to as dextrotartaric acid, and conversely L-(R,R)-(+)-tartaric acid is referred to as levotartaric acid. My understanding is that the dextro and levo prefixes refer solely to optical rotation, and the Stereochemistry section declares the same while explicitly contradicting itself. "The naturally occurring form of the acid is L-(+)-tartaric acid or levotartaric acid. The mirror-image (enantiomeric) form, dextrotartaric acid or D-(-)-tartaric acid[...] The dextro and levo prefixes are not related to the D/L configuration[...], but to the dispersion of Circularly Polarized Light (Optical rotatory dispersion ORD), (+) = dextrorotatory, (−) = levorotatory." It is plain by the parenthetical signs that the L-(R,R) is dextro and the D-(S,S) is levo. In the Diastereomer article, section "Example", is a picture that supports this nomenclature. If I am mistaken, I would highly appreciate an explanation. LibertéCognitive (talk) 04:00, 1 September 2016 (UTC)

I second this concern. The L form is the dextrarotatory form (+). This is an error. — Preceding unsigned comment added by Wisebridge (talkcontribs) 14:44, 17 October 2016 (UTC)

“rotated the Circular Polarized Light in opposite directions”[edit]

Some basic understanding of light polarization will not hurt. Incnis Mrsi (talk) 13:08, 30 September 2016 (UTC)

Which label for the natural isomer[edit]

Corrction, levotartaric acid(RR) is the natural form while dextro(SS) is the synthetic form. —Preceding unsigned comment added by (talk) 17:27, 18 October 2010 (UTC)

Thanks for leaving a note. I think you have it backwards, at least based on prices from Aldrich, the R,R isomer is cheaper and thus natural(?).--Smokefoot (talk) 22:46, 14 October 2016 (UTC)