Capsaicin - wikipedia Capsaicin Capsaicin Names Preferred IUPAC name ( 6E ) - N - ( ( 4 - Hydroxy - 3 - methoxyphenyl ) methyl ) - 8 - methylnon - 6 - enamide Other names ( E ) - N - ( 4 - Hydroxy - 3 - methoxybenzyl ) - 8 - methylnon - 6 - enamide 8 - Methyl - N - vanillyl - trans - 6 - nonenamide trans - 8 - Methyl - N - vanillylnon - 6 - enamide ( E ) - Capsaicin Capsicine Capsicin CPS Identifiers CAS Number 404 - 86 - 4 3D model ( JSmol ) Interactive image ChEBI CHEBI : 3374 ChEMBL ChEMBL294199 ChemSpider 1265957 ECHA InfoCard 100.006. 337 EC Number 206 - 969 - 8 IUPHAR / BPS 2486 KEGG C06866 PubChem CID 1548943 UNII S07O44R1ZM InChI InChI = 1S / C18H27NO3 / c1 - 14 ( 2 ) 8 - 6 - 4 - 5 - 7 - 9 - 18 ( 21 ) 19 - 13 - 15 - 10 - 11 - 16 ( 20 ) 17 ( 12 - 15 ) 22 - 3 / h6, 8, 10 - 12, 14, 20H, 4 - 5, 7, 9, 13H2, 1 - 3H3, ( H, 19, 21 ) / b8 - 6 + Key : YKPUWZUDDOIDPM - SOFGYWHQSA - N InChI = 1 / C18H27NO3 / c1 - 14 ( 2 ) 8 - 6 - 4 - 5 - 7 - 9 - 18 ( 21 ) 19 - 13 - 15 - 10 - 11 - 16 ( 20 ) 17 ( 12 - 15 ) 22 - 3 / h6, 8, 10 - 12, 14, 20H, 4 - 5, 7, 9, 13H2, 1 - 3H3, ( H, 19, 21 ) / b8 - 6 + Key : YKPUWZUDDOIDPM - SOFGYWHQBQ SMILES O = C ( NCc1cc ( OC ) c ( O ) cc1 ) CCCC / C = C / C ( C ) C Properties Chemical formula C H NO Molar mass 305.42 g mol Appearance crystalline white powder Odor highly volatile and pungent Melting point 62 to 65 ° C ( 144 to 149 ° F ; 335 to 338 K ) Boiling point 210 to 220 ° C ( 410 to 428 ° F ; 483 to 493 K ) 0.01 Torr Solubility in water 0.0013 g / 100 mL Solubility soluble in alcohol, ether, benzene slightly soluble in CS, HCl, petroleum Vapor pressure 6992132000000000000 ♠ 1.32 × 10 mm Hg at 7002298150000000000 ♠ 25 ° C UV - vis ( λ ) 280 nm Structure Crystal structure monoclinic Pharmacology ATC code M02AB01 ( WHO ) N01BX04 ( WHO ) License data EU EMA : by INN Hazards Main hazards Toxic ( T ) Safety data sheet R - phrases ( outdated ) R24 / 25 S - phrases ( outdated ) S26, S36 / 37 / 39, S45 NFPA 704 0 Except where otherwise noted, data are given for materials in their standard state ( at 25 ° C ( 77 ° F ), 100 kPa ). Y verify ( what is ? ) Infobox references Capsaicin Heat Above peak Scoville scale 16,000,000 SHU Capsaicin ( / kæpˈseɪ. ɪsɪn / ( INN ) ; 8 - methyl - N - vanillyl - 6 - nonenamide ) is an active component of chili peppers, which are plants belonging to the genus Capsicum. It is an irritant for mammals, including humans, and produces a sensation of burning in any tissue with which it comes into contact. Capsaicin and several related compounds are called capsaicinoids and are produced as secondary metabolites by chili peppers, probably as deterrents against certain mammals and fungi. Pure capsaicin is a hydrophobic, colorless, highly pungent, crystalline to waxy compound. Contents 1 History 2 Capsaicinoids 3 Biosynthesis 3.1 History 3.2 Biosynthetic pathway 4 Natural function 5 Uses 5.1 Food 5.2 Research and pharmaceutical use 5.3 Pepper spray and pests 5.4 Equestrian sports 6 Mechanism of action 7 Toxicity 7.1 Acute health effects 7.2 Treatment after exposure 7.3 Effects on weight loss and regain 8 See also 9 References 9.1 Footnotes 10 Further reading 11 External links History The compound was first extracted in impure form in 1816 by Christian Friedrich Bucholz ( 1770 -- 1818 ). He called it `` capsicin '', after the genus Capsicum from which it was extracted. John Clough Thresh ( 1850 -- 1932 ), who had isolated capsaicin in almost pure form, gave it the name `` capsaicin '' in 1876. Karl Micko isolated capsaicin in its pure form in 1898. Capsaicin 's chemical composition was first determined by E.K. Nelson in 1919, who also partially elucidated capsaicin 's chemical structure. Capsaicin was first synthesized in 1930 by Ernst Spath and Stephen F. Darling. In 1961, similar substances were isolated from chili peppers by the Japanese chemists S. Kosuge and Y. Inagaki, who named them capsaicinoids. In 1873 German pharmacologist Rudolf Buchheim ( 1820 -- 1879 ) and in 1878 the Hungarian doctor Endre Hőgyes stated that `` capsicol '' ( partially purified capsaicin ) caused the burning feeling when in contact with mucous membranes and increased secretion of gastric acid. Capsaicinoids The most commonly occurring capsaicinoids are capsaicin ( 69 % ), dihydrocapsaicin ( 22 % ), nordihydrocapsaicin ( 7 % ), homocapsaicin ( 1 % ), and homodihydrocapsaicin ( 1 % ). Capsaicin and dihydrocapsaicin ( both 16.0 million SHU ) are the most pungent capsaicinoids, nordihydrocapsaicin ( 9.1 million SHU ), homocapsaicin and homodihydrocapsaicin ( both 8.6 million SHU ) are about half as hot. Besides the five natural capsaicinoids ( table below ), one synthetic member of the capsaicinoid family exists : vanillylamide of n - nonanoic acid ( VNA, also PAVA ). Capsaicinoid name Abbrev. Typical relative amount Scoville heat units Chemical structure Capsaicin 69 % 16,000,000 Dihydrocapsaicin DHC 22 % 16,000,000 Nordihydrocapsaicin NDHC 7 % 9,100,000 Homocapsaicin HC 1 % 8,600,000 Homodihydrocapsaicin HDHC 1 % 8,600,000 Nonivamide PAVA 9,200,000 Biosynthesis History The general biosynthetic pathway of capsaicin and other capsaicinoids was elucidated in the 1960s by Bennett and Kirby, and Leete and Louden. Radiolabeling studies identified phenylalanine and valine as the precursors to capsaicin. Enzymes of the phenylpropanoid pathway, phenylalanine ammonia lyase ( PAL ), cinnamate 4 - hydroxylase ( C4H ), caffeic acid O - methyltransferase ( COMT ) and their function in capsaicinoid biosynthesis were identified later by Fujiwake et al., and Sukrasno and Yeoman. Suzuki et al. are responsible for identifying leucine as another precursor to the branched - chain fatty acid pathway. It was discovered in 1999 that pungency of chili peppers is related to higher transcription levels of key enzymes of the phenylpropanoid pathway, phenylalanine ammonia lyase, cinnamate 4 - hydroxylase, caffeic acid O - methyltransferase. Similar studies showed high transcription levels in the placenta of chili peppers with high pungency of genes responsible for branched - chain fatty acid pathway. Biosynthetic pathway Plants exclusively of the Capsicum genus produce capsaicinoids, which are alkaloids. Capsaicin is believed to be synthesized in the interlocular septum of chili peppers and depends on the gene AT3, which resides at the pun1 locus, and which encodes a putative acyltransferase. Biosynthesis of the capsaicinoids occurs in the glands of the pepper fruit where capsaicin synthase condenses vanillylamine from the phenylpropanoid pathway with an acyl - CoA moiety produced by the branched - chain fatty acid pathway. Capsaicin is the most abundant capsaicinoid found in the Capsicum genus, but at least ten other capsaicinoid variants exist. Phenylalanine supplies the precursor to the phenylpropanoid pathway while leucine or valine provide the precursor for the branched - chain fatty acid pathway. To produce capsaicin, 8 - methyl - 6 - nonenoyl - CoA is produced by the branched - chain fatty acid pathway and condensed with vanillamine. Other capsaicinoids are produced by the condensation of vanillamine with various acyl - CoA products from the branched - chain fatty acid pathway, which is capable of producing a variety of acyl - CoA moieties of different chain length and degrees of unsaturation. All condensation reactions between the products of the phenylpropanoid and branched - chain fatty acid pathway are mediated by capsaicin synthase to produce the final capsacinoid product. Vanillamine is a product of the phenylpropanoid pathway Valine enters the branched fatty acid pathway to produce 8 - methyl - 6 - nonenoyl - CoA Capsaicin synthase condenses vanillamine and 8 - methy - 6 - nonenoyl CoA to produce capsaicin Natural function Capsaicin is present in large quantities in the placental tissue ( which holds the seeds ), the internal membranes and, to a lesser extent, the other fleshy parts of the fruits of plants in the genus Capsicum. The seeds themselves do not produce any capsaicin, although the highest concentration of capsaicin can be found in the white pith of the inner wall, where the seeds are attached. The seeds of Capsicum plants are dispersed predominantly by birds : in birds, the TRPV1 channel does not respond to capsaicin or related chemicals ( avian vs. mammalian TRPV1 show functional diversity and selective sensitivity ). This is advantageous to the plant, as chili pepper seeds consumed by birds pass through the digestive tract and can germinate later, whereas mammals have molar teeth which destroy such seeds and prevent them from germinating. Thus, natural selection may have led to increasing capsaicin production because it makes the plant less likely to be eaten by animals that do not help it disperse. There is also evidence that capsaicin may have evolved as an anti-fungal agent : the fungal pathogen Fusarium, which is known to infect wild chilies and thereby reduce seed viability, is deterred by capsaicin, which thus limits this form of predispersal seed mortality. In 2006, it was discovered that the venom of a certain tarantula species activates the same pathway of pain as is activated by capsaicin ; this was the first demonstrated case of such a shared pathway in both plant and animal anti-mammal defense. Uses Food Curry dishes Because of the burning sensation caused by capsaicin when it comes in contact with mucous membranes, it is commonly used in food products to provide added spice or `` heat '' ( piquancy ), usually in the form of spices such as chili powder and paprika. In high concentrations, capsaicin will also cause a burning effect on other sensitive areas, such as skin or eyes. The degree of heat found within a food is often measured on the Scoville scale. Because people enjoy the heat, there has long been a demand for capsaicin - spiced products like curry, chili con carne, and hot sauces such as Tabasco sauce and salsa. It is common for people to experience pleasurable and even euphoric effects from ingesting capsaicin. Folklore among self - described `` chiliheads '' attributes this to pain - stimulated release of endorphins, a different mechanism from the local receptor overload that makes capsaicin effective as a topical analgesic. Research and Pharmaceutical use Capsaicin is used as an analgesic in topical ointments, nasal sprays ( Sinol - M ), and dermal patches to relieve pain, typically in concentrations between 0.025 % and 0.1 %. It may be applied in cream form for the temporary relief of minor aches and pains of muscles and joints associated with arthritis, backache, strains and sprains, often in compounds with other rubefacients. It is also used to reduce the symptoms of peripheral neuropathy such as post-herpetic neuralgia caused by shingles. Capsaicin transdermal patch ( Qutenza ) for the management of this particular therapeutic indication ( pain due to post-herpetic neuralgia ) was approved as a therapeutic by the U.S. FDA, but a subsequent application for Qutenza to be used as an analgesic in HIV neuralgia was refused. Although capsaicin creams have been used to treat psoriasis for reduction of itching, a review of six clinical trials involving topical capsaicin for treatment of pruritus concluded there was insufficient evidence of effect. There is insufficient clinical evidence to determine the role of ingested capsaicin on a variety of human disorders, including obesity, diabetes, cancer and cardiovascular diseases. Pepper spray and pests Capsaicinoids are also an active ingredient in riot control and personal defense pepper spray agents. When the spray comes in contact with skin, especially eyes or mucous membranes, it produces pain and breathing difficulty, discouraging protestors and assailants. Capsaicin is also used to deter pests, specifically mammalian pests. Targets of capsaicin repellants include voles, deer, rabbits, squirrels, bears, insects, and attacking dogs. Ground or crushed dried chili pods may be used in birdseed to deter rodents, taking advantage of the insensitivity of birds to capsaicin. The Elephant Pepper Development Trust claims the use of chili peppers to improve crop security for rural African communities. Notably, an article published in the Journal of Environmental Science and Health in 2006 states that `` Although hot chili pepper extract is commonly used as a component of household and garden insect - repellent formulas, it is not clear that the capsaicinoid elements of the extract are responsible for its repellency. '' The first pesticide product using solely capsaicin as the active ingredient was registered with the U.S. Department of Agriculture in 1962. Equestrian sports Capsaicin is a banned substance in equestrian sports because of its hypersensitizing and pain - relieving properties. At the show jumping events of the 2008 Summer Olympics, four horses tested positive for the substance, which resulted in disqualification. Mechanism of action The burning and painful sensations associated with capsaicin result from its chemical interaction with sensory neurons. Capsaicin, as a member of the vanilloid family, binds to a receptor called the vanilloid receptor subtype 1 ( TRPV1 ). First cloned in 1997, TRPV1 is an ion channel - type receptor. TRPV1, which can also be stimulated with heat, protons and physical abrasion, permits cations to pass through the cell membrane when activated. The resulting depolarization of the neuron stimulates it to signal the brain. By binding to the TRPV1 receptor, the capsaicin molecule produces similar sensations to those of excessive heat or abrasive damage, explaining why the spiciness of capsaicin is described as a burning sensation. Early research showed capsaicin to evoke a long - onset current in comparison to other chemical agonists, suggesting the involvement of a significant rate - limiting factor. Subsequent to this, the TRPV1 ion channel has been shown to be a member of the superfamily of TRP ion channels, and as such is now referred to as TRPV1. There are a number of different TRP ion channels that have been shown to be sensitive to different ranges of temperature and probably are responsible for our range of temperature sensation. Thus, capsaicin does not actually cause a chemical burn, or indeed any direct tissue damage at all, when chili peppers are the source of exposure. The inflammation resulting from exposure to capsaicin is believed to be the result of the body 's reaction to nerve excitement. For example, the mode of action of capsaicin in inducing bronchoconstriction is thought to involve stimulation of C fibers culminating in the release of neuropeptides. In essence, the body inflames tissues as if it has undergone a burn or abrasion and the resulting inflammation can cause tissue damage in cases of extreme exposure, as is the case for many substances that cause the body to trigger an inflammatory response. Toxicity Acute Health effects Capsaicin is a strong irritant requiring proper protective goggles, respirators, and proper hazardous material - handling procedures. Capsaicin takes effect upon skin contact ( irritant, sensitizer ), eye contact ( irritant ), ingestion, and inhalation ( lung irritant, lung sensitizer ). LD in mice is 47.2 mg / kg. Painful exposures to capsaicin - containing peppers are among the most common plant - related exposures presented to poison centers. They cause burning or stinging pain to the skin and, if ingested in large amounts by adults or small amounts by children, can produce nausea, vomiting, abdominal pain, and burning diarrhea. Eye exposure produces intense tearing, pain, conjunctivitis, and blepharospasm. Treatment after exposure The primary treatment is removal from exposure. Contaminated clothing should be removed and placed in airtight bags to prevent secondary exposure. For external exposure, bathing the mucous membrane surfaces that have contacted capsaicin with oily compounds such as vegetable oil, paraffin oil, petroleum jelly ( Vaseline ), creams, or polyethylene glycol is the most effective way to attenuate the associated discomfort ; since oil and capsaicin are both hydrophobic hydrocarbons the capsaicin that has not already been absorbed into tissues will be picked up into solution and easily removed. Capsaicin can also be washed off the skin using soap, shampoo, or other detergents. Plain water is ineffective at removing capsaicin, as are bleach, sodium metabisulfite and topical antacid suspensions. Capsaicin is soluble in alcohol, which can be used to clean contaminated items. When capsaicin is ingested, cold milk is an effective way to relieve the burning sensation ( due to caseins having a detergent effect on capsaicin ) ; and room - temperature sugar solution ( 10 % ) at 20 ° C ( 68 ° F ) is almost as effective. The burning sensation will slowly fade away over several hours if no actions are taken. Capsaicin - induced asthma might be treated with oral antihistamines or corticosteroids. Effects on weight loss and regain There is no evidence showing that weight loss is directly correlated with ingesting capsaicin. Well - designed clinical studies have not been performed because the pungency of capsaicin in prescribed doses under research prevents subject compliance. See also Allicin, the active piquant flavor chemical in uncooked garlic, and to a lesser extent onions ( see those articles for discussion of other chemicals in them relating to pungency, and eye irritation ) Allyl isothiocyanate ( also allyl mercaptan ), the active piquant chemical in mustard, radishes, horseradish, and wasabi Capsazepine, capsaicin antagonist Gingerol and shogaol, the active piquant flavor chemicals in ginger List of investigational analgesics Naga Viper pepper, Bhut Jolokia Pepper, Carolina Reaper, Trinidad Moruga Scorpion ; some of the world 's most capsaicin - rich fruits Resiniferatoxin, an ultrapotent capsaicin analog in Euphorbia plants syn - Propanethial - S - oxide, the major active piquant chemical in onions Piperine, the active piquant flavor chemical in black pepper References Footnotes Jump up ^ `` Capsaicin ''. ChemSpider, Royal Society of Chemistry, Cambridge, UK. 2018. Retrieved 9 June 2018. ^ Jump up to : `` Capsaicin, Experimental Properties ''. PubChem, US National Library of Medicine. 2 June 2018. Retrieved 9 June 2018. ^ Jump up to : Govindarajan, V. S ; Sathyanarayana, M. N ( 1991 ). `` Capsicum -- production, technology, chemistry, and quality. Part V. Impact on physiology, pharmacology, nutrition, and metabolism ; structure, pungency, pain, and desensitization sequences ''. Critical Reviews in Food Science and Nutrition. 29 ( 6 ) : 435 -- 74. doi : 10.1080 / 10408399109527536. PMID 2039598. Jump up ^ What Made Chili Peppers So Spicy ? Talk of the Nation, 15 August 2008. Jump up ^ History of early research on capsaicin : Harvey W. Felter and John U. Lloyd, King 's American Dispensatory ( Cincinnati, Ohio : Ohio Valley Co., 1898 ), vol. 1, page 435. Available on - line at : Henriette 's Herbal. Andrew G. Du Mez, `` A century of the United States pharmocopoeia 1820 -- 1920. I. The galenical oleoresins '' ( Ph. D. dissertation, University of Wisconsin, 1917 ), pages 111 -- 132. Available on - line at : Archive.org. C.F. Bucholz ( 1816 ) `` Chemische Untersuchung der trockenen reifen spanischen Pfeffers '' ( Chemical investigation of dry, ripe Spanish peppers ), Almanach oder Taschenbuch für Scheidekünstler und Apotheker ( Weimar ) ( Almanac or Pocket - book for Analysts ( Chemists ) and Apothecaries ), vol. 37, pages 1 -- 30. ( Note : Christian Friedrich Bucholz 's surname has been variously spelled as `` Bucholz '', `` Bucholtz '', or `` Buchholz ''. ) The results of Bucholz 's and Braconnot 's analyses of Capsicum annuum appear in : Jonathan Pereira, The Elements of Materia Medica and Therapeutics, 3rd U.S. ed. ( Philadelphia, Pennsylvania : Blanchard and Lea, 1854 ), vol. 2, page 506. Biographical information about Christian Friedrich Bucholz is available in : Hugh J. Rose, Henry J. Rose, and Thomas Wright, ed. s, A New General Biographical Dictionary ( London, England : 1857 ), vol. 5, page 186. Biographical information about C.F. Bucholz is also available ( in German ) on - line at : Allgemeine Deutsche Biographie. Some other early investigators who also extracted the active component of peppers : Benjamin Maurach ( 1816 ) `` Pharmaceutisch - chemische Untersuchung des spanischen Pfeffers '' ( Pharmaceutical - chemical investigation of Spanish peppers ), Berlinisches Jahrbuch für die Pharmacie, vol. 17, pages 63 -- 73. Abstracts of Maurach 's paper appear in : ( i ) Repertorium für die Pharmacie, vol. 6, page 117 - 119 ( 1819 ) ; ( ii ) Allgemeine Literatur - Zeitung, vol. 4, no. 18, page 146 ( Feb. 1821 ) ; ( iii ) `` Spanischer oder indischer Pfeffer '', System der Materia medica..., vol. 6, pages 381 -- 386 ( 1821 ) ( this reference also contains an abstract of Bucholz 's analysis of peppers ). French chemist Henri Braconnot ( 1817 ) `` Examen chemique du Piment, de son principe âcre, et de celui des plantes de la famille des renonculacées '' ( Chemical investigation of the chili pepper, of its pungent principle ( constituent, component ), and of that of plants of the family Ranunculus ), Annales de Chemie et de Physique, vol. 6, pages 122 - 131. Danish geologist Johann Georg Forchhammer in : Hans C. Oersted ( 1820 ) `` Sur la découverte de deux nouveaux alcalis végétaux '' ( On the discovery of two new plant alkalis ), Journal de physique, de chemie, d'histoire naturelle et des arts, vol. 90, pages 173 -- 174. German apothecary Ernst Witting ( 1822 ) `` Considerations sur les bases vegetales en general, sous le point de vue pharmaceutique et descriptif de deux substances, la capsicine et la nicotianine '' ( Thoughts on the plant bases in general from a pharmaceutical viewpoint, and description of two substances, capsicin and nicotine ), Beiträge für die pharmaceutische und analytische Chemie, vol. 3, pages 43ff. Jump up ^ In a series of articles, J.C. Thresh obtained capsaicin in almost pure form : J.C. Thresh ( 1876 ) `` Isolation of capsaicin, '' The Pharmaceutical Journal and Transactions, 3rd series, vol. 6, pages 941 -- 947 ; J.C. Thresh ( 8 July 1876 ) `` Capsaicin, the active principle in Capsicum fruits, '' The Pharmaceutical Journal and Transactions, 3rd series, vol. 7, no. 315, pages 21 ff. ( Note : This article is summarized in : `` Capsaicin, the active principle in Capsicum fruits, '' The Analyst, vol. 1, no. 8, pages 148 -- 149, ( 1876 ). ). In The Pharmaceutical Journal and Transactions, volume 7, see also pages 259ff and 473 ff and in vol. 8, see pages 187ff ; Year Book of Pharmacy... ( 1876 ), pages 250 and 543 ; J.C. Thresh ( 1877 ) `` Note on Capsaicin, '' Year Book of Pharmacy..., pages 24 -- 25 ; J.C. Thresh ( 1877 ) `` Report on the active principle of Cayenne pepper, '' Year Book of Pharmacy..., pages 485 -- 488. Jump up ^ Obituary notice of J.C. Thresh : `` John Clough Thresh, M.D., D. Sc., and D.P.H ''. The British Medical Journal. 1 ( 3726 ) : 1057 -- 1058. 1932. doi : 10.1136 / bmj. 1.3726. 1057 - c. PMC 2521090. PMID 20776886. Jump up ^ J King, H Wickes Felter, J Uri Lloyd ( 1905 ) A King 's American Dispensatory. Eclectic Medical Publications ( ISBN 1888483024 ) Jump up ^ Micko K ( 1898 ). `` Zur Kenntniss des Capsaïcins '' ( On our knowledge of capsaicin ). Zeitschrift für Untersuchung der Nahrungs - und Genussmittel ( Journal for the Investigation of Necessities and Luxuries ) ( in German ). 1 ( 12 ) : 818 -- 829. doi : 10.1007 / bf02529190. Jump up ^ Karl Micko ( 1899 ). `` Über den wirksamen Bestandtheil des Cayennespfeffers '' ( On the active component of Cayenne pepper ). Zeitschrift für Untersuchung der Nahrungs - und Genussmittel ( in German ). 2 ( 5 ) : 411 -- 412. doi : 10.1007 / bf02529197. Jump up ^ Nelson EK ( 1919 ). `` The constitution of capsaicin, the pungent principle of capsicum ''. J. Am. Chem. Soc. 41 ( 7 ) : 1115 -- 1121. doi : 10.1021 / ja02228a011. Jump up ^ Späth E, Darling SF ( 1930 ). `` Synthese des Capsaicins ''. Chem. Ber. 63B : 737 -- 743. Jump up ^ S Kosuge, Y Inagaki, H Okumura ( 1961 ). Studies on the pungent principles of red pepper. Part VIII. On the chemical constitutions of the pungent principles. Nippon Nogei Kagaku Kaishi ( J. Agric. Chem. Soc. ), 35, 923 -- 927 ; ( en ) Chem. Abstr. 1964 ; 60, 9827g. Jump up ^ ( ja ) S Kosuge, Y Inagaki ( 1962 ) Studies on the pungent principles of red pepper. Part XI. Determination and contents of the two pungent principles. Nippon Nogei Kagaku Kaishi J. Agric. Chem. Soc., 36, pp. 251 Jump up ^ Rudolf Buchheim ( 1873 ) `` Über die ' scharfen ' Stoffe '' ( On the `` hot '' substance ), Archiv der Heilkunde ( Archive of Medicine ), vol. 14, pages 1ff. See also : R. Buchheim ( 1872 ) `` Fructus Capsici, '' Vierteljahresschrift für praktische Pharmazie ( Quarterly Journal for Practical Pharmacy ), vol. 4, pages 507ff. ; reprinted ( in English ) in : Proceedings of the American Pharmaceutical Association, vol. 22, pages 106ff ( 1873 ). Jump up ^ Endre Hőgyes, `` Adatok a paprika ( Capsicum annuum ) élettani hatásához '' ( Data on the physiological effects of the pepper ( Capsicum annuum ) ), Orvos - természettudumányi társulatot Értesítője ( Bulletin of the Medical Science Association ) ( 1877 ) ; reprinted in : Orvosi Hetilap ( Medical Journal ) ( 1878 ), 10 pages. Published in German as : `` Beitrage zur physiologischen Wirkung der Bestandtheile des Capiscum annuum ( Spanischer Pfeffer ) '' ( Contributions on the physiological effects of components of Capsicum annuum ( Spanish pepper ) ), Archiv für Experimentelle Pathologie und Pharmakologie, vol. 9, pages 117 -- 130 ( 1878 ). See springerlink.com Jump up ^ F.A. Flückiger, Pharmakognosie des Pflanzenreiches ( Berlin, Germany : Gaertner 's Verlagsbuchhandlung, 1891 ). Jump up ^ Bennett DJ, Kirby GW ( 1968 ). `` Constitution and biosynthesis of capsaicin ''. J. Chem. Soc. C : 442. doi : 10.1039 / j39680000442. Jump up ^ Bennett DJ, Kirby GW ( 1968 ) Constitution and biosynthesis of capsaicin. J Chem Soc C 4 : 442 -- 446 Jump up ^ Leete E, Louden MC ( 1968 ). `` Biosynthesis of capsaicin and dihydrocapsaicin in Capsicum frutescens ''. J Am Chem Soc. 90 ( 24 ) : 6837 -- 6841. doi : 10.1021 / ja01026a049. PMID 5687710. Jump up ^ Fujiwake H, Suzuki T, Iwai K ( 1982a ) Intracellular distribution of enzymes and intermediates involved in biosynthesis of capsaicin and its analogues in Capsicum fruits. Agric Biol Chem 46 : 2685 -- 2689 Jump up ^ Fujiwake H, Suzuki T, Iwai K ( 1982b ) Capsaicinoid formation in the protoplast from placenta of Capsicum fruits. Agric Biol Chem 46 : 2591 -- 2592 Jump up ^ Sukrasno N, Yeoman MM ( 1993 ). `` Phenylpropanoid metabolism during growth and development of Capsicum frutescens fruits ''. Phytochemistry. 32 ( 4 ) : 839 -- 844. doi : 10.1016 / 0031 - 9422 ( 93 ) 85217 - f. Jump up ^ Suzuki T, Kawada T, Iwai K ( 1981 ) Formation and metabolism of pungent principle of Capsicum fruits. 9. Biosynthesis of acyl moieties of capsaicin and its analogs from valine and leucine in Capsicum fruits. Plant Cell Physiol 22 : 23 -- 32 Jump up ^ Curry J, Aluru M, Mendoza M, Nevarez J, Melendrez M, O'Connell MA ( 1999 ) Transcripts for possible capsaicinoid biosynthetic genes are differentially accumulated in pungent and non-pungent Capsicum spp. Plant Sci 148 : 47 -- 57 Jump up ^ Nelson EK, Dawson LE ( 1923 ). `` Constitution of capsaicin, the pungent principle of Capsicum. III ''. J Am Chem Soc. 45 ( 9 ) : 2179 -- 2181. doi : 10.1021 / ja01662a023. Jump up ^ Stewart C, Kang BC, Liu K, et al. ( June 2005 ). `` The Pun1 gene for pungency in pepper encodes a putative acyltransferase ''. Plant J. 42 ( 5 ) : 675 -- 88. doi : 10.1111 / j. 1365 - 313X. 2005.02410. x. PMID 15918882. ^ Jump up to : Leete E, Louden MC ( 1968 ). `` Biosynthesis of capsaicin and dihydrocapsaicin in Capsicum frutescens ''. J. Am. Chem. Soc. 90 ( 24 ) : 6837 -- 6841. doi : 10.1021 / ja01026a049. PMID 5687710. ^ Jump up to : Bennett DJ, Kirby GW ( 1968 ). `` Constitution and biosynthesis of capsaicin ''. J. Chem. Soc. C. 1968 : 442 -- 446. Jump up ^ Fujiwake H. ; Suzuki T. ; Oka S. ; Iwai K. ( 1980 ). `` Enzymatic formation of capsaicinoid from vanillylamine and iso - type fatty acids by cell - free extracts of Capsicum annuum var. annuum cv. Karayatsubusa ''. Agricultural and Biological Chemistry. 44 ( 12 ) : 2907 -- 2912. doi : 10.1271 / bbb1961. 44.2907. Jump up ^ I. Guzman, P.W. Bosland, and M.A. O'Connell, `` Chapter 8 : Heat, Color, and Flavor Compounds in Capsicum Fruit '' in David R. Gang, ed., Recent Advances in Phytochemistry 41 : The Biological Activity of Phytochemicals ( New York, New York : Springer, 2011 ), pages 117 -- 118. Jump up ^ Kozukue N, Han JS, Kozukue E, Lee SJ, Kim JA, Lee KR, Levin CE, Friedman M ( 2005 ). `` Analysis of eight capsaicinoids in peppers and pepper - containing foods by high - performance liquid chromatography and liquid chromatography - mass spectrometry ''. J Agric Food Chem. 53 ( 23 ) : 9172 -- 9181. doi : 10.1021 / jf050469j. Jump up ^ Thiele R, Mueller - Seitz E, Petz M ( 2008 ). `` Chili pepper fruits : presumed precursors of fatty acids characteristic for capsaicinoids ''. J Agric Food Chem. 56 ( 11 ) : 4219 -- 4224. doi : 10.1021 / jf073420h. Jump up ^ New Mexico State University -- College of Agriculture and Home Economics ( 2005 ). `` Chile Information -- Frequently Asked Questions ''. Archived from the original on 4 May 2007. Retrieved 17 May 2007. Jump up ^ Tewksbury, J.J. ; Nabhan, G.P. ( 2001 ). `` Seed dispersal. Directed deterrence by capsaicin in chilies ''. Nature. 412 ( 6845 ) : 403 -- 404. doi : 10.1038 / 35086653. PMID 11473305. Jump up ^ Joshua J. Tewksbury ; Karen M. Reagan ; Noelle J. Machnicki ; Tomás A. Carlo ; David C. Haak ; Alejandra Lorena Calderón Peñaloza ; Douglas J. Levey ( 19 August 2008 ), `` Evolutionary ecology of pungency in wild chilies '', Proceedings of the National Academy of Sciences, 105 ( 33 ) : 11808 -- 11811, doi : 10.1073 / pnas. 0802691105, PMC 2575311, PMID 18695236, retrieved 30 June 2010 Jump up ^ Siemens J, Zhou S, Piskorowski R, et al. ( November 2006 ). `` Spider toxins activate the capsaicin receptor to produce inflammatory pain ''. Nature. 444 ( 7116 ) : 208 -- 12. doi : 10.1038 / nature05285. PMID 17093448. ^ Jump up to : Gorman J ( 20 September 2010 ). `` A Perk of Our Evolution : Pleasure in Pain of Chilies ''. New York Times. Retrieved 16 March 2015. ^ Jump up to : Rollyson WD, et al. ( 2014 ). `` Bioavailability of capsaicin and its implications for drug delivery ''. J Control Release. 196 : 96 -- 105. doi : 10.1016 / j. jconrel. 2014.09. 027. PMC 4267963. PMID 25307998. ^ Jump up to : Fattori, V ; Hohmann, M.S. ; Rossaneis, A.C. ; Pinho - Ribeiro, F.A. ; Verri, W.A. ( 2016 ). `` Capsaicin : Current Understanding of Its Mechanisms and Therapy of Pain and Other Pre-Clinical and Clinical Uses ''. Molecules. 21 ( 7 ) : 844. doi : 10.3390 / molecules21070844. PMID 27367653. Jump up ^ `` FDA Approves New Drug Treatment for Long - Term Pain Relief after Shingles Attacks ''. U.S. Food and Drug Administration. 17 November 2009. Retrieved 5 January 2016. Jump up ^ Hitt E ( 9 March 2012 ). `` FDA Turns Down Capsaicin Patch for Painful Neuropathy in HIV ''. Medscape Medical News, WebMD. Retrieved 5 January 2016. Jump up ^ Glinski W, Glinska - Ferenz M, Pierozynska - Dubowska M ( 1991 ). `` Neurogenic inflammation induced by capsaicin in patients with psoriasis ''. Acta dermato - venereologica. Acta Derm Venereol. 71 ( 1 ) : 51 -- 4. PMID 1711752. Jump up ^ Ellis CN, Berberian B, Sulica VI, Dodd WA, Jarratt MT, Katz HI, Prawer S, Krueger G, Rex IH Jr, Wolf JE ( 1993 ). `` A double - blind evaluation of topical capsaicin in pruritic psoriasis ''. J. Am. Acad. Dermatol. 29 ( 3 ) : 438 -- 42. doi : 10.1016 / 0190 - 9622 ( 93 ) 70208 - B. PMID 7688774. Jump up ^ Gooding SM, Canter PH, Coelho HF, Boddy K, Ernst E ( 2010 ). `` Systematic review of topical capsaicin in the treatment of pruritus ''. Int J Dermatol. 49 ( 8 ) : 858 -- 65. doi : 10.1111 / j. 1365 - 4632.2010. 04537. x. PMID 21128913. Jump up ^ Blum, Deborah ( 21 November 2011 ), `` About Pepper Spray '', Scientific - American Guest Blog ( Web ), London, UK : Macmillan Publishers, Ltd., retrieved 17 February 2016 Jump up ^ `` Capsaicin '', Toxicology Data Network ( Database ), Bethesda, MD : National Institutes of Health ( published 30 June 2006 ), 15 March 1983, retrieved 17 February 2016 Jump up ^ Smith, Gregory ; Stopford, Woodhall ( 2007 -- 08 -- 17 ), `` Health Hazards of Pepper Spray '', North Carolina Medical Journal ( Web ), Morrisville, NC : North Carolina Institute of Medicine ( published 30 June 2006 ), ISSN 0029 - 2559, archived from the original on 17 August 2000 Check date values in : year = ( help ) ^ Jump up to : `` R.E.D. Facts for Capsaicin '' ( PDF ). United States Environmental Protection Agency. Archived from the original ( PDF ) on 24 October 2012. Retrieved 13 November 2012. Jump up ^ Jensen, P.G. ; Curtis, P.D. ; Dunn, J.A. ; Austic, R.E. ; Richmond, M.E. ( 2003 ). `` Field evaluation of capsaicin as a rodent aversion agent for poultry feed ''. Pest Management Science. 59 ( 9 ) : 1007 -- 1015. doi : 10.1002 / ps. 705. PMID 12974352. Jump up ^ Antonious GF, Meyer JE, Snyder JC ( 2006 ). `` Toxicity and repellency of hot pepper extracts to spider mite, Tetranychus urticae Koch ''. J Environ Sci Health B. 41 ( 8 ) : 1383 -- 91. doi : 10.1080 / 0360123060096419. PMID 17090499. Jump up ^ `` Olympic horses fail drugs tests ''. BBC News. 21 August 2008. Retrieved 1 April 2010. Jump up ^ Story GM, Crus - Orengo L ( July -- August 2007 ). `` Feel the burn ''. American Scientist. 95 ( 4 ) : 326 -- 333. doi : 10.1511 / 2007.66. 326. Jump up ^ Caterina, MJ ; Schumacher, MA ; Tominaga, M ; Rosen, TA ; Levine, JD ; Julius, D ( 23 October 1997 ). `` The capsaicin receptor : a heat - activated ion channel in the pain pathway ''. Nature. 389 ( 6653 ) : 816 -- 24. doi : 10.1038 / 39807. PMID 9349813. Jump up ^ Geppetti, Pierangelo & Holzer, Peter ( 1996 ). Neurogenic Inflammation. CRC Press, 1996. Jump up ^ Fuller, R.W., Dixon, C.M.S. & Barnes, P.J. ( 1985 ). Bronchoconstrictor response to inhaled capsaicin in humans '' J. Appl. Physiol 58, 1080 -- 1084. PubMed, CAS, Web of Science ® Times Cited : 174 ^ Jump up to : `` Capsaicin Material Safety Data Sheet '' ( PDF ). sciencelab.com. 2007. Retrieved 13 July 2007. Jump up ^ Johnson, Wilbur ( 2007 ). `` Final report on the safety assessment of capsicum annuum extract, capsicum annuum fruit extract, capsicum annuum resin, capsicum annuum fruit powder, capsicum frutescens fruit, capsicum frutescens fruit extract, capsicum frutescens resin, and capsaicin ''. Int. J. Toxicol. 26 Suppl 1 : 3 -- 106. doi : 10.1080 / 10915810601163939. PMID 17365137. Jump up ^ Krenzelok, E.P. ; Jacobsen, T.D. ( 1997 - 08 - 01 ). `` Plant exposures... a national profile of the most common plant genera ''. Veterinary and Human Toxicology. 39 ( 4 ) : 248 -- 249. ISSN 0145 - 6296. PMID 9251180. ^ Jump up to : Goldfrank, L R. ( ed. ). Goldfrank 's Toxicologic Emergencies. New York, New York : McGraw - Hill. p. 1167. ISBN 0 - 07 - 144310 - X. Jump up ^ General Chemistry Online : Fire and Spice Jump up ^ Wu Nasrawia, Christina ; Marie Pangborn, Rose ( April 1990 ). `` Temporal effectiveness of mouth - rinsing on capsaicin mouth - burn ''. Physiol. Behav. 47 ( 4 ) : 617 -- 23. doi : 10.1016 / 0031 - 9384 ( 90 ) 90067 - E. PMID 2385629. Jump up ^ Diepvens K, Westerterp KR, Westerterp - Plantenga MS ( 2007 ). `` Obesity and thermogenesis related to the consumption of caffeine, ephedrine, capsaicin, and green tea ''. Am J Physiol : Regulatory, Integrative and Comparative Physiology. 292 ( 1 ) : R77 -- 85. doi : 10.1152 / ajpregu. 00832.2005. PMID 16840650. Further reading Abdel - Salam, Omar M.E. ( ed. ) : Capsaicin as a Therapeutic Molecule. Springer, 2014. ISBN 978 - 3 - 0348 - 0827 - 9 ( print ) ; ISBN 978 - 3 - 0348 - 0828 - 6 ( eBook ). External links Wikimedia Commons has media related to Capsaicin. Look up capsaicin in Wiktionary, the free dictionary. Capsaicin Technical Fact Sheet -- National Pesticide Information Center Fire and Spice : The molecular basis for flavor TRP channel modulators TRPA Activators 4 - Hydroxynonenal 4 - Oxo - 2 - nonenal 4, 5 - EET 12S - HpETE 15 - Deoxy - Δ - prostaglandin J2 α - Sanshool ( ginger, Sichuan and melegueta peppers ) Acrolein Allicin ( garlic ) Allyl isothiocyanate ( mustard, radish, horseradish, wasabi ) AM404 Bradykinin Cannabichromene ( cannabis ) Cannabidiol ( cannabis ) Cannabigerol ( cannabis ) Cinnamaldehyde ( cinnamon ) CR gas ( dibenzoxazepine ; DBO ) CS gas ( 2 - chlorobenzal malononitrile ) Curcumin ( turmeric ) Dehydroligustilide ( celery ) Diallyl disulfide Dicentrine ( Lindera spp. ) Farnesyl thiosalicylic acid Formalin Gingerols ( ginger ) Hepoxilin A3 Hepoxilin B3 Hydrogen peroxide Icilin Isothiocyanate Ligustilide ( celery, Angelica acutiloba ) Linalool ( Sichuan pepper, thyme ) Methylglyoxal Methyl salicylate ( wintergreen ) N - Methylmaleimide Nicotine ( tobacco ) Oleocanthal ( olive oil ) Paclitaxel ( Pacific yew ) Paracetamol ( acetaminophen ) PF - 4840154 Phenacyl chloride Polygodial ( Dorrigo pepper ) Shogaols ( ginger, Sichuan and melegueta peppers ) Tear gases Tetrahydrocannabinol ( cannabis ) Thiopropanal S - oxide ( onion ) Umbellulone ( Umbellularia californica ) WIN 55,212 - 2 Blockers Dehydroligustilide ( celery ) Nicotine ( tobacco ) Ruthenium red TRPC Activators Adhyperforin ( St John 's wort ) Diacyl glycerol GSK1702934A Hyperforin ( St John 's wort ) Substance P Blockers DCDPC DHEA - S Flufenamic acid GSK417651A GSK2293017A Meclofenamic acid N - ( p - amylcinnamoyl ) anthranilic acid Niflumic acid Pregnenolone sulfate Progesterone Pyr3 Tolfenamic acid TRPM Activators ADP - ribose BCTC Calcium ( intracellular ) Cold Coolact P Cooling Agent 10 CPS - 369 Eucalyptol ( eucalyptus ) Frescolat MGA Frescolat ML Geraniol Hydroxycitronellal Icilin Linalool Menthol ( mint ) PMD 38 Pregnenolone sulfate Rutamarin ( Ruta graveolens ) Steviol glycosides ( e.g., stevioside ) ( Stevia rebaudiana ) Sweet tastants ( e.g., glucose, fructose, sucrose ; indirectly ) Thio - BCTC WS - 3 WS - 12 WS - 23 Blockers Capsazepine Clotrimazole DCDPC Elismetrep Flufenamic acid Meclofenamic acid Mefenamic acid N - ( p - amylcinnamoyl ) anthranilic acid Nicotine ( tobacco ) Niflumic acid Ruthenium red Rutamarin ( Ruta graveolens ) Tolfenamic acid TPPO TRPML Activators MK6 - 83 PI ( 3, 5 ) P SF - 22 TRPP Activators Triptolide ( Tripterygium wilfordii ) Blockers Ruthenium red TRPV Activators 2 - APB 5 ', 6 ' - EET 9 - HODE 9 - oxoODE 12S - HETE 12S - HpETE 13 - HODE 13 - oxoODE 20 - HETE α - Sanshool ( ginger, Sichuan and melegueta peppers ) Allicin ( garlic ) AM404 Anandamide Bisandrographolide ( Andrographis paniculata ) Camphor ( camphor laurel, rosemary, camphorweed, African blue basil, camphor basil ) Cannabidiol ( cannabis ) Cannabidivarin ( cannabis ) Capsaicin ( chili pepper ) Carvacrol ( oregano, thyme, pepperwort, wild bergamot, others ) DHEA Diacyl glycerol Dihydrocapsaicin ( chili pepper ) Estradiol Eugenol ( basil, clove ) Evodiamine ( Euodia ruticarpa ) Gingerols ( ginger ) GSK1016790A Heat Hepoxilin A3 Hepoxilin B3 Homocapsaicin ( chili pepper ) Homodihydrocapsaicin ( chili pepper ) Incensole ( incense ) Lysophosphatidic acid Low pH ( acidic conditions ) Menthol ( mint ) N - Arachidonoyl dopamine N - Oleoyldopamine N - Oleoylethanolamide Nonivamide ( PAVA ) ( PAVA spray ) Nordihydrocapsaicin ( chili pepper ) Paclitaxel ( Pacific yew ) Paracetamol ( acetaminophen ) Phorbol esters ( e.g., 4α - PDD ) Piperine ( black pepper, long pepper ) Polygodial ( Dorrigo pepper ) Probenecid Protons RhTx Rutamarin ( Ruta graveolens ) Resiniferatoxin ( RTX ) ( Euphorbia resinifera / pooissonii ) Shogaols ( ginger, Sichuan and melegueta peppers ) Tetrahydrocannabivarin ( cannabis ) Thymol ( thyme, oregano ) Tinyatoxin ( Euphorbia resinifera / pooissonii ) Tramadol Vanillin ( vanilla ) Zucapsaicin Blockers α - Spinasterol ( Vernonia tweediana ) AMG - 517 Asivatrep BCTC Cannabigerol ( cannabis ) Cannabigerolic acid ( cannabis ) Cannabigerovarin ( cannabis ) Cannabinol ( cannabis ) Capsazepine DCDPC DHEA DHEA - S Flufenamic acid GRC - 6211 HC - 067047 Lanthanum Meclofenamic acid N - ( p - amylcinnamoyl ) anthranilic acid NGD - 8243 Niflumic acid Pregnenolone sulfate RN - 1734 RN - 9893 Ruthenium red SB - 705498 Tivanisiran Tolfenamic acid See also : Receptor / signaling modulators Ion channel modulators GND : 7538173 - 4 LCCN : sh85020016 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Capsaicin&oldid=853347672 '' Categories : Capsaicinoids Hidden categories : CS1 German - language sources ( de ) CS1 errors : dates Use dmy dates from May 2016 ECHA InfoCard ID from Wikidata Drug has EMA link Chembox having DSD data Articles containing unverified chemical infoboxes All articles with unsourced statements Articles with unsourced statements from May 2014 Articles with unsourced statements from January 2010 Wikipedia articles with GND identifiers Wikipedia articles with LCCN identifiers Talk Contents About Wikipedia تۆرکجه Български Català Čeština Cymraeg Dansk Deutsch Español فارسی Français 한국어 Bahasa Indonesia Italiano עברית Latviešu Lietuvių Magyar Bahasa Melayu Nederlands 日本 語 Nordfriisk Norsk Polski Português Română Русский Simple English Slovenčina Српски / srpski Srpskohrvatski / српскохрватски Suomi Svenska ไทย Türkçe Українська اردو Tiếng Việt 中文 30 more Edit links This page was last edited on 4 August 2018, at 03 : 21 ( UTC ). 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Question: where does the heat in chillies come from
Answer: Capsaicin