Raspberry ketone
Verifiedfieldschanged
Watchedfieldschanged
Verifiedrevid464380314
Reference[1]
Pin4-(4-Hydroxyphenyl)butan-2-one
Othernamesp-Hydroxybenzyl acetone; 4-(p-Hydroxyphenyl)-2-butanone; Frambinone; Oxyphenylon; Rheosmin; Rasketone

Raspberry ketone is a naturally occurring phenolic compound that is the primary aroma compound of red raspberries.

Occurrence

Raspberry ketone occurs in a variety of fruits, including raspberries, cranberries, and blackberries.[2] It is released by orchid flowers, e.g. Dendrobium superbum (syn D. anosmum),[3] and several Bulbophyllum species[4][5][6] to attract raspberry ketone-responsive male Dacini fruit flies. It is biosynthesized from coumaroyl-CoA.[7] It can be extracted from the fruit, yielding about 1–4 mg per kg of raspberries.[8]

Preparation

Since the natural abundance of raspberry ketone is very low, it is prepared industrially by a variety of methods from chemical intermediates.[9] One of the ways this can be done is through a Claisen-Schmidt condensation followed by catalytic hydrogenation. First, acetone is condensed with 4-hydroxybenzaldehyde to form an α,β-unsaturated ketone. Then the alkene part is reduced to the alkane. This two-step method produces raspberry ketone in 99% yield.[10] There is a less expensive hydrogenation catalyst, nickel boride, which also demonstrates high selectivity towards hydrogenation of the double bond of enone.[11]

Uses

Raspberry ketone is sometimes used in perfumery, in cosmetics, and as a food additive to impart a fruity odor. It is one of the most expensive natural flavor components used in the food industry. The natural compound can cost as much as $20,000 per kg.[8]

Marketing

Although products containing this compound are marketed for weight loss, there is no clinical evidence for this effect in humans.[12][13] They are called "ketones" because of the ketone (acetone) group at their end, which is shared with ketone bodies.

Safety

Little is known about the long-term safety of raspberry ketone supplements,[14][15] especially since little research has been done with humans.[16] Toxicological models indicate a potential for cardiotoxic effects, as well as effects on reproduction and development.[14] Furthermore, in many dietary supplements containing raspberry ketones, manufacturers add other ingredients such as caffeine which may have unsafe effects.[16]

In 1965, the US Food and Drug Administration classified raspberry ketone as generally recognized as safe (GRAS) for the small quantities used to flavor foods.[17]

See also

References

  1. ^ Catalog of Organics and Fine Chemicals, Acros Organics, 2004/05, page 1250.
  2. ^ "Raspberry Ketone, Molecule of the Month". University of Bristol.
  3. ^ Nishida, R.; Iwahashi, I.; Tan, K.H. (1993). "Accumulation of Dendrobium (Orchidaceae) flower fragrance in the rectal glands by males of the melon fly, Dacus cucurbitae (Tephritidae)". Journal of Chemical Ecology. 19 (4): 713–722. doi:10.1007/BF00985003. PMID 24249012
  4. ^ Tan, K.H. & Nishida, R. (2005). "Synomone or Kairomone? - Bulbophyllum apertum (Orchidaceae) flower releases raspberry ketone to attract Bactrocera fruit flies". Journal of Chemical Ecology. 31 (3): 509–519. doi:10.1007/s10886-005-2023-8
  5. ^ Tan, K.H. & Tan, L.T. (2018). "Movements of floral parts and roles of the tooth on column wall of Bulbophyllum praetervisum (Orchidaceae) flower for pollination by Dacini fruit flies (Diptera: Tephritidae)". Journal of Pollination Ecology. 24 (17): 157–163. doi:10.26786/1920-7603(2018)19
  6. ^ Nakahira, M.; Ono, H.; Wee, S.L.; Nishida, R. (2018). "Floral synomone diversification of Bulbophyllum sibling species (Orchidaceae) in attracting fruit fly pollinators". Biochemical Systematics and Ecology. 81: 86–95. doi:10.1016/j.bse.2018.10.002. hdl:2433/235528
  7. ^ "MetaCyc Pathway: raspberry ketone biosynthesis". MetaCyc. Retrieved 2012-07-12.
  8. ^ Beekwilder, Jules; Van Der Meer, Ingrid M.; Sibbesen, Ole; Broekgaarden, Mans; Qvist, Ingmar; Mikkelsen, Joern D.; Hall, Robert D. (2007). "Microbial production of natural raspberry ketone". Biotechnology Journal. 2 (10): 1270–9. doi:10.1002/biot.200700076. PMID 17722151. S2CID 32088996
  9. ^ Tateiwa, Jun-Ichi; Horiuchi, Hiroki; Hashimoto, Keiji; Yamauchi, Takayoshi; Uemura, Sakae (1994). "Cation-Exchanged Montmorillonite-Catalyzed Facile Friedel-Crafts Alkylation of Hydroxy and Methoxy Aromatics with 4-Hydroxybutan-2-one to Produce Raspberry Ketone and Some Pharmaceutically Active Compounds". The Journal of Organic Chemistry. 59 (20): 5901–4. doi:10.1021/jo00099a017
  10. ^ Smith, Leverett R. (1996). "Rheosmin ('Raspberry Ketone') and Zingerone, and Their Preparation by Crossed Aldol-Catalytic Hydrogenation Sequences". The Chemical Educator. 1 (3): 1–18. doi:10.1007/s00897960034a. S2CID 94729547
  11. ^ Bandarenko, Mikhail & Kovalenko, Vitaly (2014). "Synthesis of Raspberry and Ginger Ketones by Nickel Boride-catalyzed Hydrogenation of 4-Arylbut-3-en-2-ones". Zeitschrift für Naturforschung B. 69b (8): 885–888. doi:10.5560/ZNB.2014-4118
  12. ^ "Raspberry Ketones: Uses, Health Benefits, and Risks". WebMD
  13. ^ "Raspberry Ketone". WebMD
  14. ^ Bredsdorff L, Wedebye EB, Nikolov NG, Hallas-Møller T, Pilegaard K (2015). "Raspberry ketone in food supplements - High intake, few toxicity data - A cause for safety concern?". Regul Toxicol Pharmacol. 73 (1): 196–200. doi:10.1016/j.yrtph.2015.06.022. PMID 26160596. S2CID 38312188
  15. ^ Cathy Wong. "Raspberry Ketones for Weight Loss". About.com. Archived from the original on 2016-01-14. Retrieved 2012-11-02.
  16. ^ Canberra, Jules. "What's All The Hype About Raspberry Ketone?". Authority Health. Retrieved 30 October 2017.
  17. ^ "4-(p-Hydroxyphenyl)-2-butanone". Food and Cosmetics Toxicology. 16: 781–2. 1978. doi:10.1016/S0015-6264(78)80113-8