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Record Information
Creation Date2014-09-11 05:17:53 UTC
Update Date2014-12-24 20:26:57 UTC
Accession NumberT3D4817
Common NameRiboflavin
ClassSmall Molecule
DescriptionNutritional factor found in milk, eggs, malted barley, liver, kidney, heart, and leafy vegetables. The richest natural source is yeast. It occurs in the free form only in the retina of the eye, in whey, and in urine; its principal forms in tissues and cells are as flavin mononucleotide and flavin-adenine dinucleotide.
Compound Type
  • Amide
  • Drug
  • Food Toxin
  • Metabolite
  • Natural Compound
  • Nutraceutical
  • Organic Compound
  • Photosensitizing Agent
  • Plant Toxin
  • Vitamin B Complex
Chemical Structure
Benzo[g]pteridine riboflavin deriv.
E 101
Flavin BB
Food Yellow 15
Russupteridine yellow III
San Yellow B
Vitamin B2
Vitamin G
Vitasan B2
Chemical FormulaC17H20N4O6
Average Molecular Mass376.364 g/mol
Monoisotopic Mass376.138 g/mol
CAS Registry Number83-88-5
IUPAC Name7,8-dimethyl-10-[(2S,3S,4R)-2,3,4,5-tetrahydroxypentyl]-2H,3H,4H,10H-benzo[g]pteridine-2,4-dione
Traditional Nameriboflavin
InChI IdentifierInChI=1S/C17H20N4O6/c1-7-3-9-10(4-8(7)2)21(5-11(23)14(25)12(24)6-22)15-13(18-9)16(26)20-17(27)19-15/h3-4,11-12,14,22-25H,5-6H2,1-2H3,(H,20,26,27)/t11-,12+,14-/m0/s1
Chemical Taxonomy
Description belongs to the class of organic compounds known as flavins. Flavins are compounds containing a flavin (7,8-dimethyl-benzo[g]pteridine-2,4-dione) moiety, with a structure characterized by an isoalloaxzine tricyclic ring.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
ClassPteridines and derivatives
Sub ClassAlloxazines and isoalloxazines
Direct ParentFlavins
Alternative Parents
  • Flavin
  • Diazanaphthalene
  • Quinoxaline
  • Pyrimidone
  • Pyrazine
  • Pyrimidine
  • Benzenoid
  • Heteroaromatic compound
  • Vinylogous amide
  • Secondary alcohol
  • Lactam
  • Polyol
  • Azacycle
  • Alcohol
  • Hydrocarbon derivative
  • Organic oxide
  • Organopnictogen compound
  • Organic oxygen compound
  • Primary alcohol
  • Organooxygen compound
  • Organonitrogen compound
  • Organic nitrogen compound
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External Descriptors
Biological Properties
StatusDetected and Not Quantified
Cellular Locations
  • Cytoplasm
  • Extracellular
Biofluid LocationsNot Available
Tissue Locations
  • Erythrocyte
  • Heart
  • Kidney
  • Liver
  • Prostate
Riboflavin MetabolismSMP00070 map00740
ApplicationsNot Available
Biological RolesNot Available
Chemical RolesNot Available
Physical Properties
AppearanceWhite powder.
Experimental Properties
Melting Point280 dec°C
Boiling PointNot Available
Solubility84.7 mg/L (at 25°C)
Predicted Properties
Water Solubility0.66 g/LALOGPS
pKa (Strongest Acidic)5.97ChemAxon
pKa (Strongest Basic)-2.6ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count9ChemAxon
Hydrogen Donor Count5ChemAxon
Polar Surface Area155.05 ŲChemAxon
Rotatable Bond Count5ChemAxon
Refractivity96.27 m³·mol⁻¹ChemAxon
Polarizability37.51 ųChemAxon
Number of Rings3ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash KeyView
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-006x-4980000000-dd278a577316361d270aJSpectraViewer | MoNA
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-006x-4980000000-dd278a577316361d270aJSpectraViewer | MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0btc-9014000000-75f046dc3c6cb008690eJSpectraViewer
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (4 TMS) - 70eV, Positivesplash10-0zfs-5146149000-f9db57dd1ccd4a014604JSpectraViewer
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-004i-0019000000-86365dedafa031aa7787JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-0006-4390000000-ac1b59ab7cc2209f4241JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-00dj-4900000000-72d33eb27b9bd6a13d9eJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF (UPLC Q-Tof Premier, Waters) , Positivesplash10-004l-0569000000-874b71fdc78d04853bf0JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF (UPLC Q-Tof Premier, Waters) , Negativesplash10-0a4i-0091000000-a82c54d3153103fcdb1fJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-qTof , Positivesplash10-004i-0239000000-659ca9fae9643f3ce73dJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , negativesplash10-0a4i-0091000000-a82c54d3153103fcdb1fJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , negativesplash10-0a4i-0090000000-2aff124ee1fc62c13844JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , negativesplash10-0a4i-0090000000-f8b29c3e2c601a944a6cJSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , negativesplash10-0a4i-0090000000-4e8c9bd38ea0f5ae9a94JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-004l-0569000000-874b71fdc78d04853bf0JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-0006-0092000000-1f1be5508c1d50d8dff7JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-0006-0092000000-74bf0b86efe72fe37198JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-057i-0069000000-bb0522be4472e049dbc5JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-057i-0069000000-208440cf501d0b9050d7JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-006x-0029000000-8c3d72bf2a06d79bbd31JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-006x-0039000000-7d8dc991995cfc262ad1JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-0006-0092000000-4f524f1e6c8131751c92JSpectraViewer | MoNA
LC-MS/MSLC-MS/MS Spectrum - Linear Ion Trap , positivesplash10-0560-0069000000-edc332be3fcbf6d0c14bJSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0a6r-1029000000-cb7561783d706b360970JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0bt9-4092000000-a884c2c509c2da1c9005JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0a6r-1190000000-1d77df8220a965f08454JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-007o-9068000000-99f78bac6ce18b370145JSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0006-9141000000-70e4d57c08631d27b93dJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0006-9220000000-ddd6caad2f26c593ced0JSpectraViewer
1D NMR1H NMR SpectrumNot AvailableJSpectraViewer
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableJSpectraViewer
Toxicity Profile
Route of ExposureVitamin B2 is readily absorbed from the upper gastrointestinal tract.
Mechanism of ToxicityBinds to riboflavin hydrogenase, riboflavin kinase, and riboflavin synthase. Riboflavin is the precursor of flavin mononucleotide (FMN, riboflavin monophosphate) and flavin adenine dinucleotide (FAD). The antioxidant activity of riboflavin is principally derived from its role as a precursor of FAD and the role of this cofactor in the production of the antioxidant reduced glutathione. Reduced glutathione is the cofactor of the selenium-containing glutathione peroxidases among other things. The glutathione peroxidases are major antioxidant enzymes. Reduced glutathione is generated by the FAD-containing enzyme glutathione reductase.
MetabolismHepatic. Half Life: 66-84 minutes
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)No indication of carcinogenicity to humans (not listed by IARC).
Uses/SourcesFor the treatment of ariboflavinosis (vitamin B2 deficiency).
Minimum Risk LevelNot Available
Health EffectsNot Available
SymptomsNot Available
TreatmentNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDDB00140
PubChem Compound ID493570
ChemSpider ID6501
UniProt IDNot Available
ChEBI ID17015
CTD IDNot Available
Stitch IDNot Available
ACToR IDNot Available
Wikipedia LinkRiboflavin
Synthesis Reference

Hansgeorg Ernst, Wolfram Schmidt, Joachim Paust, “Preparation of riboflavin.” U.S. Patent US4567261, issued August, 1958.

General References
  1. Zempleni J, Galloway JR, McCormick DB: Pharmacokinetics of orally and intravenously administered riboflavin in healthy humans. Am J Clin Nutr. 1996 Jan;63(1):54-66. [8604671 ]
  2. Mathew JL, Kabi BC, Rath B: Anti-oxidant vitamins and steroid responsive nephrotic syndrome in Indian children. J Paediatr Child Health. 2002 Oct;38(5):450-37. [12354259 ]
  3. Booth CK, Clark T, Fenn A: Folic acid, riboflavin, thiamine, and vitamin B-6 status of a group of first-time blood donors. Am J Clin Nutr. 1998 Nov;68(5):1075-80. [9808225 ]
  4. Boisvert WA, Mendoza I, Castaneda C, De Portocarrero L, Solomons NW, Gershoff SN, Russell RM: Riboflavin requirement of healthy elderly humans and its relationship to macronutrient composition of the diet. J Nutr. 1993 May;123(5):915-25. [8487103 ]
  5. Mikalunas V, Fitzgerald K, Rubin H, McCarthy R, Craig RM: Abnormal vitamin levels in patients receiving home total parenteral nutrition. J Clin Gastroenterol. 2001 Nov-Dec;33(5):393-6. [11606856 ]
  6. Belko AZ, Obarzanek E, Roach R, Rotter M, Urban G, Weinberg S, Roe DA: Effects of aerobic exercise and weight loss on riboflavin requirements of moderately obese, marginally deficient young women. Am J Clin Nutr. 1984 Sep;40(3):553-61. [6475825 ]
  7. Alexander M, Emanuel G, Golin T, Pinto JT, Rivlin RS: Relation of riboflavin nutriture in healthy elderly to intake of calcium and vitamin supplements: evidence against riboflavin supplementation. Am J Clin Nutr. 1984 Apr;39(4):540-6. [6546833 ]
  8. Baeckert PA, Greene HL, Fritz I, Oelberg DG, Adcock EW: Vitamin concentrations in very low birth weight infants given vitamins intravenously in a lipid emulsion: measurement of vitamins A, D, and E and riboflavin. J Pediatr. 1988 Dec;113(6):1057-65. [3142982 ]
  9. Maiani G, Mobarhan S, Nicastro A, Virgili F, Scaccini C, Ferro-Luzzi A: [Determination of glutathione reductase activity in erythrocytes and whole blood as an indicator of riboflavin nutrition]. Acta Vitaminol Enzymol. 1983;5(3):171-8. [6650303 ]
  10. Bamji MS, Bhaskaram P, Jacob CM: Urinary riboflavin excretion and erythrocyte glutathione reductase activity in preschool children suffering from upper respiratory infections and measles. Ann Nutr Metab. 1987;31(3):191-6. [3592624 ]
  11. Ajayi OA: Bioavailability of riboflavin from fortified palm juice. Plant Foods Hum Nutr. 1989 Dec;39(4):375-80. [2631092 ]
  12. Kodentsova VM, Vrzhesinskaya OA, Spirichev VB: Fluorometric riboflavin titration in plasma by riboflavin-binding apoprotein as a method for vitamin B2 status assessment. Ann Nutr Metab. 1995;39(6):355-60. [8678471 ]
  13. Bates CJ, Powers HJ: A simple fluorimetric assay for pyridoxamine phosphate oxidase in erythrocyte haemolysates: effects of riboflavin supplementation and of glucose 6-phosphate dehydrogenase deficiency. Hum Nutr Clin Nutr. 1985 Mar;39(2):107-15. [4019261 ]
  14. Brun TA, Chen J, Campbell TC, Boreham J, Feng Z, Parpia B, Shen TF, Li M: Urinary riboflavin excretion after a load test in rural China as a measure of possible riboflavin deficiency. Eur J Clin Nutr. 1990 Mar;44(3):195-206. [2369885 ]
  15. Mulherin DM, Thurnham DI, Situnayake RD: Glutathione reductase activity, riboflavin status, and disease activity in rheumatoid arthritis. Ann Rheum Dis. 1996 Nov;55(11):837-40. [8976642 ]
  16. Rao PN, Levine E, Myers MO, Prakash V, Watson J, Stolier A, Kopicko JJ, Kissinger P, Raj SG, Raj MH: Elevation of serum riboflavin carrier protein in breast cancer. Cancer Epidemiol Biomarkers Prev. 1999 Nov;8(11):985-90. [10566553 ]
  17. Zhou X, Huang C, Hong J, Yao S: [Nested case-control study on riboflavin levels in blood and urine and the risk of lung cancer]. Wei Sheng Yan Jiu. 2003 Nov;32(6):597-8, 601. [14963913 ]
  18. Thurnham DI, Zheng SF, Munoz N, Crespi M, Grassi A, Hambidge KM, Chai TF: Comparison of riboflavin, vitamin A, and zinc status of Chinese populations at high and low risk for esophageal cancer. Nutr Cancer. 1985;7(3):131-43. [3878498 ]
  19. Bates CJ, Prentice AM, Paul AA, Prentice A, Sutcliffe BA, Whitehead RG: Riboflavin status in infants born in rural Gambia, and the effect of a weaning food supplement. Trans R Soc Trop Med Hyg. 1982;76(2):253-8. [7101408 ]
  20. Dror Y, Stern F, Komarnitsky M: Optimal and stable conditions for the determination of erythrocyte glutathione reductase activation coefficient to evaluate riboflavin status. Int J Vitam Nutr Res. 1994;64(4):257-62. [7883462 ]
  21. Switzer BR, Stark AH, Atwood JR, Ritenbaugh C, Travis RG, Wu HM: Development of a urinary riboflavin adherence marker for a wheat bran fiber community intervention trial. Cancer Epidemiol Biomarkers Prev. 1997 Jun;6(6):439-42. [9184778 ]
  22. Sreekumar A, Poisson LM, Rajendiran TM, Khan AP, Cao Q, Yu J, Laxman B, Mehra R, Lonigro RJ, Li Y, Nyati MK, Ahsan A, Kalyana-Sundaram S, Han B, Cao X, Byun J, Omenn GS, Ghosh D, Pennathur S, Alexander DC, Berger A, Shuster JR, Wei JT, Varambally S, Beecher C, Chinnaiyan AM: Metabolomic profiles delineate potential role for sarcosine in prostate cancer progression. Nature. 2009 Feb 12;457(7231):910-4. doi: 10.1038/nature07762. [19212411 ]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available


General Function:
Riboflavin kinase activity
Specific Function:
Catalyzes the phosphorylation of riboflavin (vitamin B2) to form flavin-mononucleotide (FMN), hence rate-limiting enzyme in the synthesis of FAD. Essential for TNF-induced reactive oxygen species (ROS) production. Through its interaction with both TNFRSF1A and CYBA, physically and functionally couples TNFRSF1A to NADPH oxidase. TNF-activation of RFK may enhance the incorporation of FAD in NADPH oxidase, a critical step for the assembly and activation of NADPH oxidase.
Gene Name:
Uniprot ID:
Molecular Weight:
17623.08 Da
  1. Werner R, Manthey KC, Griffin JB, Zempleni J: HepG2 cells develop signs of riboflavin deficiency within 4 days of culture in riboflavin-deficient medium. J Nutr Biochem. 2005 Oct;16(10):617-24. [16081269 ]
  2. Solovieva IM, Kreneva RA, Errais Lopes L, Perumov DA: The riboflavin kinase encoding gene ribR of Bacillus subtilis is a part of a 10 kb operon, which is negatively regulated by the yrzC gene product. FEMS Microbiol Lett. 2005 Feb 1;243(1):51-8. [15668000 ]
  3. Ishchuk OP, Iatsyshyn VIu, Dmytruk KV, Voronovs'kyi AIa, Fedorovych DV, Sybirnyi AA: [Construction of the flavinogenic yeast Candida famata strains with high riboflavin kinase activity using gene engineering]. Ukr Biokhim Zh. 2006 Sep-Oct;78(5):63-9. [17290783 ]
  4. Sandoval FJ, Roje S: An FMN hydrolase is fused to a riboflavin kinase homolog in plants. J Biol Chem. 2005 Nov 18;280(46):38337-45. Epub 2005 Sep 23. [16183635 ]
  5. Bertollo CM, Oliveira AC, Rocha LT, Costa KA, Nascimento EB Jr, Coelho MM: Characterization of the antinociceptive and anti-inflammatory activities of riboflavin in different experimental models. Eur J Pharmacol. 2006 Oct 10;547(1-3):184-91. Epub 2006 Jul 26. [16962092 ]
  6. Hirano G, Izumi H, Yasuniwa Y, Shimajiri S, Ke-Yong W, Sasagiri Y, Kusaba H, Matsumoto K, Hasegawa T, Akimoto M, Akashi K, Kohno K: Involvement of riboflavin kinase expression in cellular sensitivity against cisplatin. Int J Oncol. 2011 Apr;38(4):893-902. doi: 10.3892/ijo.2011.938. Epub 2011 Feb 9. [21308351 ]
General Function:
Riboflavin reductase (nadph) activity
Specific Function:
Broad specificity oxidoreductase that catalyzes the NADPH-dependent reduction of a variety of flavins, such as riboflavin, FAD or FMN, biliverdins, methemoglobin and PQQ (pyrroloquinoline quinone). Contributes to heme catabolism and metabolizes linear tetrapyrroles. Can also reduce the complexed Fe(3+) iron to Fe(2+) in the presence of FMN and NADPH. In the liver, converts biliverdin to bilirubin.
Gene Name:
Uniprot ID:
Molecular Weight:
22119.215 Da
  1. Russell TR, Demeler B, Tu SC: Kinetic mechanism and quaternary structure of Aminobacter aminovorans NADH:flavin oxidoreductase: an unusual flavin reductase with bound flavin. Biochemistry. 2004 Feb 17;43(6):1580-90. [14769034 ]
  2. van Pee KH, Patallo EP: Flavin-dependent halogenases involved in secondary metabolism in bacteria. Appl Microbiol Biotechnol. 2006 May;70(6):631-41. Epub 2006 Mar 17. [16544142 ]
General Function:
Zinc ion binding
Specific Function:
Steroid hormone receptors are ligand-activated transcription factors that regulate eukaryotic gene expression and affect cellular proliferation and differentiation in target tissues. Transcription factor activity is modulated by bound coactivator and corepressor proteins. Transcription activation is down-regulated by NR0B2. Activated, but not phosphorylated, by HIPK3 and ZIPK/DAPK3.
Gene Name:
Uniprot ID:
Molecular Weight:
98987.9 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
AC501.03 uMNVS_NR_hARNovascreen
  1. Sipes NS, Martin MT, Kothiya P, Reif DM, Judson RS, Richard AM, Houck KA, Dix DJ, Kavlock RJ, Knudsen TB: Profiling 976 ToxCast chemicals across 331 enzymatic and receptor signaling assays. Chem Res Toxicol. 2013 Jun 17;26(6):878-95. doi: 10.1021/tx400021f. Epub 2013 May 16. [23611293 ]
General Function:
Zinc ion binding
Specific Function:
Receptor for retinoic acid. Retinoic acid receptors bind as heterodimers to their target response elements in response to their ligands, all-trans or 9-cis retinoic acid, and regulate gene expression in various biological processes. The RXR/RAR heterodimers bind to the retinoic acid response elements (RARE) composed of tandem 5'-AGGTCA-3' sites known as DR1-DR5. In the absence of ligand, the RXR-RAR heterodimers associate with a multiprotein complex containing transcription corepressors that induce histone acetylation, chromatin condensation and transcriptional suppression. On ligand binding, the corepressors dissociate from the receptors and associate with the coactivators leading to transcriptional activation. RARA plays an essential role in the regulation of retinoic acid-induced germ cell development during spermatogenesis. Has a role in the survival of early spermatocytes at the beginning prophase of meiosis. In Sertoli cells, may promote the survival and development of early meiotic prophase spermatocytes. In concert with RARG, required for skeletal growth, matrix homeostasis and growth plate function (By similarity). Regulates expression of target genes in a ligand-dependent manner by recruiting chromatin complexes containing KMT2E/MLL5. Mediates retinoic acid-induced granulopoiesis.
Gene Name:
Uniprot ID:
Molecular Weight:
50770.805 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
AC507.11 uMNVS_NR_hRARa_AgonistNovascreen
  1. Sipes NS, Martin MT, Kothiya P, Reif DM, Judson RS, Richard AM, Houck KA, Dix DJ, Kavlock RJ, Knudsen TB: Profiling 976 ToxCast chemicals across 331 enzymatic and receptor signaling assays. Chem Res Toxicol. 2013 Jun 17;26(6):878-95. doi: 10.1021/tx400021f. Epub 2013 May 16. [23611293 ]