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Record Information
Creation Date2014-08-29 06:07:24 UTC
Update Date2018-03-21 17:46:12 UTC
Accession NumberT3D4253
Common NameL-Lactic acid
ClassSmall Molecule
DescriptionLactic acid is an organic acid. It is a chiral molecule, consisting of two optical isomers, L-lactic acid and D-lactic acid, with the L-isomer being the most common in living organisms. Lactic acid plays a role in several biochemical processes and is produced in the muscles during intense activity. In animals, L-lactate is constantly produced from pyruvate via the enzyme lactate dehydrogenase (LDH) in a process of fermentation during normal metabolism and exercise. It does not increase in concentration until the rate of lactate production exceeds the rate of lactate removal. This is governed by a number of factors, including monocarboxylate transporters, lactate concentration, the isoform of LDH, and oxidative capacity of tissues. The concentration of blood lactate is usually 1-2 mmol/L at rest, but can rise to over 20 mmol/L during intense exertion. There are some indications that lactate, and not glucose, is preferentially metabolized by neurons in the brain of several mammalian species, including mice, rats, and humans. Glial cells, using the lactate shuttle, are responsible for transforming glucose into lactate, and for providing lactate to the neurons. Lactate measurement in critically ill patients has been traditionally used to stratify patients with poor outcomes. However, plasma lactate levels are the result of a finely tuned interplay of factors that affect the balance between its production and its clearance. When the oxygen supply does not match its consumption, organisms adapt in many different ways, up to the point when energy failure occurs. Lactate, being part of the adaptive response, may then be used to assess the severity of the supply/demand imbalance. In such a scenario, the time to intervention becomes relevant: early and effective treatment may allow tissues and cells to revert to a normal state, as long as the oxygen machinery (i.e. mitochondria) is intact. Conversely, once the mitochondria are deranged, energy failure occurs even in the presence of normoxia. The lactate increase in critically ill patients may, therefore, be viewed as an early marker of a potentially reversible state (PMID: 16356243). When present in sufficiently high levels, lactic acid can act as an oncometabolite, an immunosuppressant, an acidogen, and a metabotoxin. An oncometabolite is a compound that promotes tumor growth and survival. An immunosuppressant reduces or arrests the activity of the immune system. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of lactic acid are associated with at least a dozen inborn errors of metabolism, including 2-methyl-3-hydroxybutyryl CoA dehydrogenase deficiency, biotinidase deficiency, fructose-1,6-diphosphatase deficiency, glycogen storage disease type 1A (GSD1A) or Von Gierke disease, glycogenosis type IB, glycogenosis type IC, glycogenosis type VI, Hers disease, lactic acidemia, Leigh syndrome, methylmalonate semialdehyde dehydrogenase deficiency, pyruvate decarboxylase E1 component deficiency, pyruvate dehydrogenase complex deficiency, pyruvate dehydrogenase deficiency, and short chain acyl CoA dehydrogenase deficiency (SCAD deficiency). Locally high concentrations of lactic acid or lactate are found near many tumors due to the upregulation of lactate dehydrogenase (PMID: 15279558). Lactic acid produced by tumors through aerobic glycolysis acts as an immunosuppressant and tumor promoter (PMID: 23729358). Indeed, lactic acid has been found to be a key player or regulator in the development and malignant progression of a variety of cancers (PMID: 22084445). A number of studies have demonstrated that malignant transformation is associated with an increase in aerobic cellular lactate excretion. Lactate concentrations in various carcinomas (e.g. uterine cervix, head and neck, colorectal region) at first diagnosis of the disease, can be relatively low or extremely high (up to 40 µmol/g) in different individual tumors or within the same lesion (PMID: 15279558). High molar concentrations of lactate are correlated with a high incidence of distant metastasis. Low lactate tumors (< median of approximately 8 µmol/g) are associated with both an overall longer and disease-free survival compared to high lactate lesions (lactate > approximately 8 µmol/g). Lactate-induced secretion of hyaluronan by tumor-associated fibroblasts creates a milieu favourable for cell migration and metastases (PMID: 22084445). An acidic environment (pH 6-6.5), which is common in many tumors, allows tumor cells to evade the immune response, and therefore allows them to grow unchecked. Locally high concentrations of lactic acid are known to markedly impede the function of normal immune cells and will lead to a loss of T-cell function of human tumor-infiltrating lymphocytes (PMID: 22084445). Lactic acid is also an organic acid and acts as a general acidogen. Abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart abnormalities, kidney abnormalities, liver damage, seizures, coma, and possibly death. These are also the characteristic symptoms of the untreated IEMs mentioned above. Many affected children with organic acidemias experience intellectual disability or delayed development.
Compound Type
  • Animal Toxin
  • Food Toxin
  • Household Toxin
  • Industrial/Workplace Toxin
  • Metabolite
  • Natural Compound
  • Organic Compound
Chemical Structure
(+)-Lactic acid
(alpha)-Lactic acid
(S)-(+)-2-Hydroxypropanoic acid
(S)-2-hydroxy-Propanoic acid
(S)-2-Hydroxypropanoic acid
(S)-2-Hydroxypropionic acid
(S)-Lactic acid
1-Hydroxyethane 1-carboxylate
1-Hydroxyethane 1-carboxylic acid
1-Hydroxyethanecarboxylic acid
2-Hydroxypropanoic acid
a-Hydroxypropanoic acid
a-Hydroxypropionic acid
alpha-Hydroxypropanoic acid
alpha-Hydroxypropionic acid
L-(+)- Lactic acid
L-2-Hydroxypropanoic acid
Lactic acid
Milk acid
Sarcolactic acid
Chemical FormulaC3H6O3
Average Molecular Mass90.078 g/mol
Monoisotopic Mass90.032 g/mol
CAS Registry Number79-33-4
IUPAC Name(2R)-2-hydroxypropanoic acid
Traditional NameD-lactic acid
InChI IdentifierInChI=1S/C3H6O3/c1-2(4)3(5)6/h2,4H,1H3,(H,5,6)/t2-/m0/s1
Chemical Taxonomy
Description belongs to the class of organic compounds known as alpha hydroxy acids and derivatives. These are organic compounds containing a carboxylic acid substituted with a hydroxyl group on the adjacent carbon.
KingdomOrganic compounds
Super ClassOrganic acids and derivatives
ClassHydroxy acids and derivatives
Sub ClassAlpha hydroxy acids and derivatives
Direct ParentAlpha hydroxy acids and derivatives
Alternative Parents
  • Alpha-hydroxy acid
  • Secondary alcohol
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Carboxylic acid derivative
  • Organic oxygen compound
  • Organic oxide
  • Hydrocarbon derivative
  • Organooxygen compound
  • Carbonyl group
  • Alcohol
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors
Biological Properties
StatusDetected and Not Quantified
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Mitochondria
Biofluid LocationsNot Available
Tissue Locations
  • All Tissues
GluconeogenesisSMP00128 Not Available
Pyruvate MetabolismSMP00060 map00620
2-Methyl-3-Hydroxybutryl CoA Dehydrogenase DeficiencySMP00137 Not Available
Biotinidase DeficiencySMP00174 Not Available
Fructose-1,6-diphosphatase deficiencySMP00562 Not Available
Glycogen Storage Disease Type 1A (GSD1A) or Von Gierke DiseaseSMP00374 Not Available
Glycogenosis, Type IBSMP00573 Not Available
Glycogenosis, Type ICSMP00574 Not Available
Glycogenosis, Type VI. Hers diseaseSMP00555 Not Available
Lactic AcidemiaSMP00313 Not Available
Leigh SyndromeSMP00196 Not Available
Methylmalonate Semialdehyde Dehydrogenase DeficiencySMP00384 Not Available
Pyruvate Decarboxylase E1 Component Deficiency (PDHE1 Deficiency)SMP00334 Not Available
Pyruvate Dehydrogenase Complex DeficiencySMP00212 Not Available
Pyruvate dehydrogenase deficiency (E2)SMP00551 Not Available
Short Chain Acyl CoA Dehydrogenase Deficiency (SCAD Deficiency)SMP00235 Not Available
ApplicationsNot Available
Biological Roles
Chemical RolesNot Available
Physical Properties
AppearanceNot Available
Experimental Properties
Melting Point16.8°C
Boiling Point122°C
SolubilityNot Available
LogPNot Available
Predicted Properties
Water Solubility562 g/LALOGPS
pKa (Strongest Acidic)3.78ChemAxon
pKa (Strongest Basic)-3.7ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area57.53 ŲChemAxon
Rotatable Bond Count1ChemAxon
Refractivity18.84 m³·mol⁻¹ChemAxon
Polarizability8.05 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash KeyView
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (Non-derivatized)splash10-00kb-0900000000-fb59ec16914501aa19abJSpectraViewer | MoNA
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-014j-0900000000-c4d9e12b4b0150eda54bJSpectraViewer | MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-00kb-0900000000-fb59ec16914501aa19abJSpectraViewer | MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0006-9000000000-a3691f383d440fb00e1fJSpectraViewer
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (2 TMS) - 70eV, Positivesplash10-01b9-9620000000-f7faa7db9c1be3d9d975JSpectraViewer
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, PositiveNot AvailableJSpectraViewer
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Negative (Annotated)splash10-000i-9000000000-704f8ff33156c82a02d1JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Negative (Annotated)splash10-000m-9000000000-023931446d9bb3330e7fJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Negative (Annotated)splash10-000l-9000000000-0fb29afb128baea2240bJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-IT , negativesplash10-000i-9000000000-d7cd347946e49a57860eJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - 40V, Negativesplash10-0006-9000000000-aee01e43e8ee93db755dJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - 10V, Negativesplash10-000f-9000000000-581a00222505e9e4b458JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - 20V, Negativesplash10-0006-9000000000-5bfd9fdf1c0df2054452JSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-006x-9000000000-5f417f4a6d08f0ab00edJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-00dm-9000000000-df7a94bb1a9cf6e78e1aJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-004j-9000000000-dc2a1b965287b9dfee9cJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-000i-9000000000-c3686a681cc9bbf039e1JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-000i-9000000000-ddad20647c2ac56efd22JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-00di-9000000000-b728b45617afcc6b67daJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-000i-9000000000-b586cb8f053eb4465b4eJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-000i-9000000000-400a5f1c0dfcc32ef2bbJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0007-9000000000-ad5eb77c7e0a96f3a40aJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0002-9000000000-00ba25458eb6c0cc2940JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0002-9000000000-00ba25458eb6c0cc2940JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0002-9000000000-00ba25458eb6c0cc2940JSpectraViewer
MSMass Spectrum (Electron Ionization)splash10-002b-9000000000-50213d6b39ef9741c466JSpectraViewer | MoNA
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
1D NMR13C NMR SpectrumNot AvailableJSpectraViewer
2D NMR[1H,1H] 2D NMR SpectrumNot AvailableJSpectraViewer
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableJSpectraViewer
Toxicity Profile
Route of ExposureNot Available
Mechanism of ToxicityAccumulation of L-lactic acid in the body has been shown to be toxic. At times of lactic acidosis, when excess intracellular lactate is released into the blood, maintenance of electroneutrality of the blood requires that a cation be released into the blood, as well. This can reduce blood pH. Lactate may exert a strong action over GABAergic networks in the developing brain, making them more inhibitory than it was previously assumed, acting either through better support of metabolites, or alterations in base intracellular pH levels, or both. (Wikipedia)
MetabolismNot Available
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)Not listed by IARC.
Uses/SourcesNot Available
Minimum Risk LevelNot Available
Health EffectsChronically high levels of Lactic acid are associated with at least a dozen inborn errors of metabolism including: 2-Methyl-3-hydroxybutyryl CoA dehydrogenase deficiency, Biotinidase deficiency, Fructose-1,6-diphosphatase deficiency, Glycogen Storage Disease Type 1A (GSD1A) or Von Gierke Disease, Glycogenosis, Type IB, Glycogenosis, Type IC, Glycogenosis, Type VI. Hers disease, Lactic Acidemia, Leigh Syndrome, Methylmalonate Semialdehyde Dehydrogenase Deficiency, Pyruvate Decarboxylase E1 Component Deficiency, Pyruvate dehydrogenase complex deficiency, Pyruvate dehydrogenase deficiency, Short Chain Acyl CoA Dehydrogenase Deficiency (SCAD Deficiency).
SymptomsNot Available
TreatmentNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDNot Available
PubChem Compound ID107689
ChemSpider ID96860
UniProt IDNot Available
CTD IDNot Available
Stitch IDNot Available
ACToR IDNot Available
Wikipedia LinkLactate
Synthesis ReferenceLao, Hanzhang; Sun, Jianrong; Wang, Jian; Qian, Zhiliang. Process for preparation of high-purity L-lactic acid. Faming Zhuanli Shenqing Gongkai Shuomingshu (2007), 9pp.
General References
  1. Valenza F, Aletti G, Fossali T, Chevallard G, Sacconi F, Irace M, Gattinoni L: Lactate as a marker of energy failure in critically ill patients: hypothesis. Crit Care. 2005;9(6):588-93. Epub 2005 Sep 28. [16356243 ]
  2. Walenta S, Schroeder T, Mueller-Klieser W: Lactate in solid malignant tumors: potential basis of a metabolic classification in clinical oncology. Curr Med Chem. 2004 Aug;11(16):2195-204. [15279558 ]
  3. Nielsen J, Ytrebo LM, Borud O: Lactate and pyruvate concentrations in capillary blood from newborns. Acta Paediatr. 1994 Sep;83(9):920-2. [7819686 ]
  4. Subramanian A, Gupta A, Saxena S, Gupta A, Kumar R, Nigam A, Kumar R, Mandal SK, Roy R: Proton MR CSF analysis and a new software as predictors for the differentiation of meningitis in children. NMR Biomed. 2005 Jun;18(4):213-25. [15627241 ]
  5. Zupke C, Sinskey AJ, Stephanopoulos G: Intracellular flux analysis applied to the effect of dissolved oxygen on hybridomas. Appl Microbiol Biotechnol. 1995 Dec;44(1-2):27-36. [8579834 ]
  6. Nicholson JK, Buckingham MJ, Sadler PJ: High resolution 1H n.m.r. studies of vertebrate blood and plasma. Biochem J. 1983 Jun 1;211(3):605-15. [6411064 ]
  7. Redjems-Bennani N, Jeandel C, Lefebvre E, Blain H, Vidailhet M, Gueant JL: Abnormal substrate levels that depend upon mitochondrial function in cerebrospinal fluid from Alzheimer patients. Gerontology. 1998;44(5):300-4. [9693263 ]
  8. Bairaktari E, Katopodis K, Siamopoulos KC, Tsolas O: Paraquat-induced renal injury studied by 1H nuclear magnetic resonance spectroscopy of urine. Clin Chem. 1998 Jun;44(6 Pt 1):1256-61. [9625050 ]
  9. Isotalo T, Talja M, Hellstrom P, Perttila I, Valimaa T, Tormala P, Tammela TL: A double-blind, randomized, placebo-controlled pilot study to investigate the effects of finasteride combined with a biodegradable self-reinforced poly L-lactic acid spiral stent in patients with urinary retention caused by bladder outlet obstruction from benign prostatic hyperplasia. BJU Int. 2001 Jul;88(1):30-4. [11446841 ]
  10. Shirai Y, Kamimura K, Seki T, Morohashi M: L-lactic acid as a mosquito (Diptera: Culicidae) repellent on human and mouse skin. J Med Entomol. 2001 Jan;38(1):51-4. [11268691 ]
  11. Wevers RA, Engelke U, Wendel U, de Jong JG, Gabreels FJ, Heerschap A: Standardized method for high-resolution 1H-NMR of cerebrospinal fluid. Clin Chem. 1995 May;41(5):744-51. [7729054 ]
  12. Commodari F, Arnold DL, Sanctuary BC, Shoubridge EA: 1H NMR characterization of normal human cerebrospinal fluid and the detection of methylmalonic acid in a vitamin B12 deficient patient. NMR Biomed. 1991 Aug;4(4):192-200. [1931558 ]
  13. Silwood CJ, Lynch E, Claxson AW, Grootveld MC: 1H and (13)C NMR spectroscopic analysis of human saliva. J Dent Res. 2002 Jun;81(6):422-7. [12097436 ]
  14. Kaya M, Moriwaki Y, Ka T, Inokuchi T, Yamamoto A, Takahashi S, Tsutsumi Z, Tsuzita J, Oku Y, Yamamoto T: Plasma concentrations and urinary excretion of purine bases (uric acid, hypoxanthine, and xanthine) and oxypurinol after rigorous exercise. Metabolism. 2006 Jan;55(1):103-7. [16324927 ]
  15. Nakayama Y, Kinoshita A, Tomita M: Dynamic simulation of red blood cell metabolism and its application to the analysis of a pathological condition. Theor Biol Med Model. 2005 May 9;2:18. [15882454 ]
  16. Hoffmann GF, Meier-Augenstein W, Stockler S, Surtees R, Rating D, Nyhan WL: Physiology and pathophysiology of organic acids in cerebrospinal fluid. J Inherit Metab Dis. 1993;16(4):648-69. [8412012 ]
  17. Khan SA, Cox IJ, Hamilton G, Thomas HC, Taylor-Robinson SD: In vivo and in vitro nuclear magnetic resonance spectroscopy as a tool for investigating hepatobiliary disease: a review of H and P MRS applications. Liver Int. 2005 Apr;25(2):273-81. [15780050 ]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available


1. GABA-A receptor (anion channel) (Protein Group)
General Function:
Inhibitory extracellular ligand-gated ion channel activity
Specific Function:
Component of the heteropentameric receptor for GABA, the major inhibitory neurotransmitter in the vertebrate brain. Functions also as histamine receptor and mediates cellular responses to histamine. Functions as receptor for diazepines and various anesthetics, such as pentobarbital; these are bound at a separate allosteric effector binding site. Functions as ligand-gated chloride channel (By similarity).
Included Proteins:
P14867 , P47869 , P34903 , P48169 , P31644 , Q16445 , P18505 , P47870 , P28472 , O14764 , P78334 , Q8N1C3 , P18507 , Q99928 , O00591 , Q9UN88