Dictionary » L » Lactic acid

Lactic acid



(1) A colorless or yellowish, syrupy, water-soluble liquid, which is a byproduct of anaerobic glucose metabolism.

(2) An intermediate product of carbohydrate metabolism (anaerobic metabolism), derived chiefly from muscle cells and red blood cells.

(3) A clear, odorless, hygroscopic organic acid abundant in many fruits, wine and sour milk.


Lactid acid level may be measured in the bloodstream in conditions of metabolic acidosis. Level of lactic acid rises during conditions of oxygen deprivation, such as shock, heart failure, and lung disease. The level also increases normally during exercise. Normal lactic acid levels are between 4.5 and 19.8 mg/dl

Lactic acid occurs in the following (optically isomeric) forms:

  • dextrorotatory form – present normally in blood and muscle tissue as a product of the anaerobic metabolism of glucose
  • levorotatory form – obtained by biological fermentation of sucrose.
  • racemic form – produced by bacterial fermentation, or by synthetic process for use mainly in dyeing and textile printing, as a flavoring and preservative agent in food, and in medicine.

IUPAC name: 2-hydroxypropanoic acid

Molecular formula: C3H6O3


  • milk acid
  • E270 (a preservative agent)

See also:

Please contribute to this project, if you have more information about this term feel free to edit this page

Results from our forum

Re: Food to ATP energy?

... of glucose are used in ATP production. Some are used to produce lactic acid, glycogen, glycerol, fat, and I'm sure there are other metabolites that I'm not thinking ...

See entire post
by tmbirkhead
Thu Aug 14, 2014 1:11 am
Forum: Cell Biology
Topic: Food to ATP energy?
Replies: 2
Views: 6032

How does pH change during sporulation? - Help

... nutrients added/removed. At first I thought maybe it had to do with lactic acid production if the thing is anaerobic...but I think my species is aerobic/facultative (commonly ...

See entire post
by keetner
Mon Oct 22, 2012 10:22 pm
Forum: Microbiology
Topic: How does pH change during sporulation? - Help
Replies: 2
Views: 2095

Re: Stomach bloating and weight gain

... avoid anything that's made with milk or a derivative of milk: lactose, lactic acid, whey, casein, caseinate. It can be in virtually anything and if you're sensitive even ...

See entire post
by Carrieo
Thu Mar 29, 2012 10:12 pm
Forum: Physiology
Topic: Stomach bloating and weight gain
Replies: 453
Views: 2917470

Why is my negative control showing results?

Hi there, so I used MRS agar to grow lactic acid bacteria. As a negative control, I used a neutral pH, 7 as suggested by members on this forum. I ...

See entire post
by ilovebiology77
Wed Feb 29, 2012 4:11 pm
Forum: Microbiology
Topic: Why is my negative control showing results?
Replies: 3
Views: 1385

Are there any pH indicators which can kill bacteria?

I'm thinking of using bromocresol purple to identify lactic acid bacteria colonies but was wondering whether there are any I should definitely avoid as it could ...

See entire post
by ilovebiology77
Tue Feb 28, 2012 7:56 pm
Forum: Microbiology
Topic: Are there any pH indicators which can kill bacteria?
Replies: 2
Views: 1489
View all matching forum results

This page was last modified 11:19, 5 May 2009. This page has been accessed 41,890 times. 
What links here | Related changes | Permanent link