Acmella oleracea

Acmella oleracea is a species of flowering herb in the family Asteraceae. Common names include toothache plant, paracress, Sichuan buttons, buzz buttons,[2] tingflowers and electric daisy.[3] Its native distribution is unclear, but it is likely derived from a Brazilian Acmella species.[4] It is grown as an ornamental and attracts fireflies when in bloom. It is used as a medicinal remedy in various parts of the world. A small, erect plant, it grows quickly and bears gold and red inflorescences. It is frost-sensitive but perennial in warmer climates.

Acmella oleracea
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Asterales
Family:	Asteraceae
Genus:	Acmella
Species:	A. oleracea
Binomial name
Acmella oleracea (L.) R.K.Jansen
Synonyms[1]
Spilanthes oleracea L. Spilanthes acmella (L.) Murray not (L.) L. Pyrethrum spilanthus Medik. Cotula pyrethraria L. Bidens fixa Hook.f. Bidens fervida Lam. Anacyclus pyrethraria (L.) Spreng. Spilanthes radicans Schrad. ex DC. Bidens fusca Lam. Bidens oleracea (L.) Cav. ex Steud. Bidens acmelloides Berg. Spilanthes oleracea var. fusca (Lam.) DC. Spilanthes fusca hort.par. ex Lam. Spilanthes acmella var. oleracea (L.) C.B.Clarke ex Hook.f.

Its specific epithet oleracea means "vegetable/herbal" in Latin and is a form of holeraceus (oleraceus).[5][6]

Culinary uses

For culinary purposes, small amounts of shredded fresh leaves are said to add a unique flavour to salads. Cooked leaves lose their strong flavour and may be used as leafy greens. Both fresh and cooked leaves are used in dishes such as stews in northern Brazil, especially in the state of Pará. They are combined with chilis and garlic to add flavor and vitamins to other foods.[7]

The flower bud has a grassy taste followed by a strong tingling or numbing sensation and often excessive salivation, with a cooling sensation in the throat.[7] The buds are known as "buzz buttons", "Sichuan buttons", "sansho buttons", and "electric buttons".[8] In India, they are used as flavoring in chewing tobacco.[8]

Virgin jambu oil

A concentrated extract of the plant, sometimes called jambu oil or jambu extract, is used as a flavoring agent in foods, chewing gum, and chewing tobacco.[9][10][11][12] The oil is traditionally extracted from all part of the plant.[9] EFSA and JECFA reviewed a feeding study in rats conducted by Moore et al. and both authorities recognized that the no adverse effect level for spilanthol was 572 mg/kg b.w./day, yielding a safe dose of spilanthol of 1.9 mg/kg b.w./day, or 133.5 mg/70-kg-male/day, 111 mg/58-kg-female/day, or 38 mg/20-kg-child/day.[11][12]

Jambu extract as a flavoring agent is described as having a citrus, herbal, tropical or musty odor, and its taste can be described as pungent, cooling, tingling, numbing, or effervescent. Thus, as described,[13] the flavor use of jambu extract includes the ability induce a mouth-watering sensation and the ability to promote the production of saliva. Spilanthol, the major constituent of jambu extract,[14] is responsible for the perception of a mouth-watering flavor sensation, as well as the ability to promote salivation as a sialogogue, perhaps through its astringent action or its pungent taste.[15][16]

Jambu extract can also be used in cosmetics and shampoos.[17]

Cultivation

This plant prefers well-drained, black (high organic content) soil. If starting outdoors, the seeds should not be exposed to cold weather, so start after last frost. Seeds need direct sunlight to germinate, so should not be buried.[18]

Medicinal uses

A decoction or infusion of the leaves and flowers is a traditional remedy for stammering, toothache, and stomatitis.[7]

An extract of the plant has been tested against various yeasts and bacteria and was essentially inactive.[19] It has been shown to have a strong diuretic action in rats.[20]

As a bush plant used for treating toothache, the analgesic effect of the Spilanthes plant has been attributed to the presence of constituents containing an N-isobutylamide moiety, such as spilanthol, a substance that has been found to be an effective sialogogue, an agent that promotes salivation.[21] Spilanthol is absorbed trans-dermally and through the buccal mucosa.[22][23] Spilanthol may activate TRPA1, a specific transient receptor potential (TRP) ion channel in the oral cavity.[24] In addition to capsaicin, allyl isothiocyanate, and cinnamaldehyde,[25] spilanthol is also reported to affect the catecholamine nerve pathways present in the oral cavity that promote the production of saliva,[14] which is responsible for its ability to induce a mouth-watering sensation when used as a flavor (and associated with the tingling or pungent flavoring sensation in some individuals).

Since 2000, there are several medicinal activities reported for Acmella oleracea:[14][26]

Pharmacological activity	Species	Part used	Type of extract	Models used
Antimalarial, larvicidal	S. acmella Murr.	Flowers	Ethanol	Anopheles, Aedes, Culex larvae
Antinociception, antihyperalgesic	S. acmella	Flowers	CWE	Formalin test of nociception and carrageenan-induced thermal hyperalgesia in rats
Antinociception, antihyperalgesic	Acmella uliginosa, (Sw.) Cass	Flowers	Methanol	Chemicals (acetic acid-induced abdominal constriction and formalin-, capsaicin-, glutamate-induced paw-licking test) and thermal models (hot-plate test) of nociception in mice
Immunomodulatory	S. acmella Murr.	Leaves	Ethanol	Macrophage function in mice
Immunomodulatory	S. acmella	Leaves	Ethanol	Neutrophil adhesion test in rat
Antiviral	S. americana	Flowers	NA	NA
Insecticidal	S. calva	Leaves and flowers	Petroleum ether, ethyl acetate and methanol	Helopeltis theivora
Antimalarial, larvicidal	S. acmella, S. calva, S. paniculata	Flowers	Hexane	A. stephensi, A. culicifacies, C. quinquefasciatus larvae
Antioxidant	S. acmella	Leaves, stems	Methanol	DPPH, SOD assay
Antihepatoxic	S. ciliata	Whole plant	Ethanol	Paracetamol-induced hepatic damage in rats
Antimicrobial	S. calva	Roots	Methanol	Oral microflora: Streptococcus mutans, Lactobacillus acidophilus and Candida albicans
Anti-inflammatory	S. acmella	Aerial parts	Ethanol	Lipopolysaccharide-activated murine macrophage model
Antimalarial, larvicidal	S. mauritiana	Aerial parts	Methanol extract	Aedes aegypti larvae
Insecticidal	S. acmella Murr.	Leaves and flowers	Aqueous	Chilo partellus
Diuretic	S. acmella	Flowers	CWE	Hydrated rats
Antioxidant	S. acmella Murr.	Aerial parts	Chloroform, hexane, ethyl actate, methanol	2,2-Diphenyl-1-picrylhydrazyl (DPPH) and superoxide dismutase (SOD) assay
Antimicrobial	S. americana	Whole plant	Aqueous, ethanol and hexane	Staphylococcus aureus, Streptococcus hemolytic, Bacillus cereus, Pseudomonas aeruginosa and Escherichia coli
Antipyretic	S. acmella Murr.	NA	Aqueous	Aspirin-treated rats
Diuretic	S. acmella	Leaves	Petroleum ether, chloroform and ethanol	Hydrated Wistar albino rats
Antimicrobial	S. paniculata	Leaves	NA	Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Microsporum gypseum
Antimicrobial	S. mauritiana	Roots and flowers	NA	Staphylococcus, Enterococcus, Pseudomonas, Escherichia and Klebsiella, Salmonella
Antimicrobial	S. mauritiana	Roots and flowers	NA	Candida species and Aspergillus species
Antimicrobial	S. acmella Linn.	Flower heads	Petroleum ether	Fusarium oxysporium, F. moniliformis, Aspergillus Niger and A. paraciticus
Local anaesthetic	S. acmella Murr.	NA	Aqueous	Xylocaine-induced guinea pig and frog
Antimalarial, larvicidal	S. mauritiana	Leaves	Crude powder	A. gambiae, Culex larvae
Anti-inflammatory	S. acmella	Aerial parts	Aqueous	Carragenan-induced paw edema in rats
Aphrodisiac	S. acmella L. Murr.	Flowers	Ethanol	Nitric oxide release in human corpus cavernosum cell line and penile erection in rats
Insecticidal	S. acmella	NA	NA	Periplaneta Americana
HIV-1 protease inhibitor	S. acmella L.	Whole plant	Chloroform, methanol and water	In vitro HIV-1 protease solution assay method
Analgesic	S. acmella	Aerial parts	Aqueous	Acetic acid-induced writhing response in albino mice
Pancreatic lipase-inhibitory	S. acmella	Flowers	Ethanol	In vitro test
Vasorelaxant	S. acmella Murr.	Aerial parts	Chloroform, hexane, ethyl acetate, methanol	Phenethylephrine-induced rat
Antimutagenic	S. calva	NA	Chloroform	Ames Salmonella/microsome assay
Convulsant	S. acmella	Whole plant	Hexane	Electroencephalograph response of rats

Active chemicals

• 
  Spilanthol: (2E,6Z,8E)-deca-2,6,8-trienoic acid isobutyl amide
• 
  (2E,7Z,9E)-Undeca-2,7,9-trienoic acid isobutyl amide, another alkylamide from Acmella oleracea
• 
  (2E)-Undeca-2-en-8,10-diynoic acid isobutyl amide

The most important taste-active molecules present are fatty acid amides such as spilanthol, which is responsible for the trigeminal and saliva-inducing effects of the plant.[27] It also contains stigmasteryl-3-O-b-D-glucopyranoside and a number of triterpenes. The isolation and total synthesis of the active ingredients have been reported.[28]

Biological pest control

Extracts were bioassayed against yellow fever mosquito (Aedes aegypti) and corn earworm moth (Helicoverpa zea) larvae. The spilanthol proved effective at killing mosquitoes, with a 24-hour LD₁₀₀ of 12.5 µg/mL, and 50% mortality at 6.25 µg/mL. The mixture of spilanthol isomers produced a 66% weight reduction of corn earworm larvae at 250 µg/mL after 6 days.[27]

See also

• Sichuan pepper

References

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4. Acmella oleracea. Archived September 27, 2007, at the Wayback Machine PROTA.
5. Parker, Peter (2018). A Little Book of Latin for Gardeners. Little Brown Book Group. p. 328. ISBN 978-1-4087-0615-2. oleraceus, holeraceus = relating to vegetables or kitchen garden
6. Whitney, William Dwight (1899). The Century Dictionary and Cyclopedia. Century Co. p. 2856. L. holeraceus, prop. oleraceus, herb-like, holus, prop. olus (oler-), herbs, vegetables
7. Benwick, B. S. Like a Taste That Tingles? Then This Bud's for You. Washington Post. October 3, 2007.
8. It's Shocking, But You Eat It. All Things Considered. NPR. February 28, 2009.
9. Burdock, George A. (2005). Fenaroli's Handbook of Flavor Ingredients (5th ed.). CRC Press. p. 983. ISBN 0849330343.
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12. "Scientific Opinion on Flavouring Group Evaluation 303 (FGE.303): Spilanthol from chemical group 30". EFSA Journal. 9 (3): 1995. March 2011. doi:10.2903/j.efsa.2011.1995.
13. Moore, G.E. "28-Day dietary toxicity study in rodents. Study No. 11326. Product Safety Labs, East Brunswick, NJ. Unpublished report to the Flavor and Extract Manufacturers Association of the United States, Washington, D.C., USA" (PDF). Retrieved 2 January 2014. Cite journal requires |journal= (help)
14. Tiwari, KL; SK Jadhav; V. Joshi (November 2011). "An updated review on medicinal herb genus Spilanthes". Journal of Chinese Integrative Medicine. 11. 9 (11): 1170–1178. doi:10.3736/jcim20111103. PMID 22088581.
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17. Europe EP1861486A1, "A process of preparing jambu extract, use of said extract, cosmetic compositions comprising thereof and cosmetic products comprising said cosmetic compositions", issued 2017-05-17
18. "Spilanthes acmella Seeds". Archived from the original on 2014-03-28. Retrieved 2014-03-28.
19. Holetz, F. B.; et al. (2002). "Screening of some plants used in the Brazilian folk medicine for the treatment of infectious diseases". Mem. Inst. Oswaldo Cruz. 97 (7): 1027–31. doi:10.1590/S0074-02762002000700017. PMID 12471432.
20. Ratnasooriya, W. D.; et al. (2004). "Diuretic activity of Spilanthes acmella flowers in rats". Journal of Ethnopharmacology. 91 (2–3): 317–20. doi:10.1016/j.jep.2004.01.006. PMID 15120455.
21. Rani, S.A.; Murty, S.U. (2006). "Antifungal potential of flower head extract of Spilanthes acmella Linn". African J. Biomedical Research. 9: 67–68. doi:10.4314/ajbr.v9i1.48776.
22. Boonen, J.; Roche, N.; Burvenich, C.; DeSpiegeler, B (2010). "Transdermal behavior of the N-alkylamide spilanthol (affinin) from Spilanthes acmella (Compositae) extract". Ethnopharmacology. 127 (1): 77–84. doi:10.1016/j.jep.2009.09.046. PMID 19808085.
23. Boonen, J. B.; Roche, N.; Burvenich, C.; DeSpiegeler, B (2010). "LC-MS profiling of N-alkylamides in Spilanthes acmella extract and the transmucosal behavior of its main bio-active spilanthol". J. Pharmaceutical and Biomedical Analysis. 53 (3): 243–249. doi:10.1016/j.jpba.2010.02.010. PMID 20227845.
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25. Iwasaki, Y. Tanabe; Kobata, K.; Watanabe, T. (2008). "TRPA1 agonists – allyl isothiocyanate and cinnamaldehyde – induce adrenal secretion" (PDF). Bioscience, Biotechnology, and Biochemistry. 72 (10): 2608–2614. doi:10.1271/bbb.80289. PMID 18838811.
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28. Ley, J. P.; et al. (2006). "Isolation and synthesis of acmellonate, a new unsaturated long chain 2-ketol ester from Spilanthes acmella". Nat. Prod. Res. 20 (9): 798–804. doi:10.1080/14786410500246733. PMID 16753916.