Bixin[1]
Skeletal formula
Names
IUPAC name
(2E,4E,6E,8E,10E,12E,14E,16Z,18E)-20-Methoxy-4,8,13,17-tetramethyl-20-oxoicosa-2,4,6,8,10,12,14,16,18-nonaenoic acid
Other names
cis-Bixin; α-Bixin; 9-cis-6,6'-Diapo-ψ,ψ-carotenedioic acid, 6-methyl ester
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.027.499 Edit this at Wikidata
UNII
  • InChI=1S/C25H30O4/c1-20(12-8-14-22(3)16-18-24(26)27)10-6-7-11-21(2)13-9-15-23(4)17-19-25(28)29-5/h6-19H,1-5H3,(H,26,27)/b7-6+,12-8+,13-9+,18-16+,19-17+,20-10+,21-11+,22-14+,23-15+ checkY
    Key: RAFGELQLHMBRHD-IFNPSABLSA-N checkY
  • InChI=1/C25H30O4/c1-20(12-8-14-22(3)16-18-24(26)27)10-6-7-11-21(2)13-9-15-23(4)17-19-25(28)29-5/h6-19H,1-5H3,(H,26,27)/b7-6+,12-8+,13-9+,18-16+,19-17+,20-10+,21-11+,22-14+,23-15-
    Key: RAFGELQLHMBRHD-SLEZCNMEBU
  • O=C(O)\C=C\C(=C\C=C\C(=C\C=C\C=C(\C=C\C=C(/C=C/C(=O)OC)C)C)C)C
Properties
C25H30O4
Molar mass 394.511 g·mol−1
Appearance Orange crystals
Melting point 198 °C (cis-isomer)
217 °C (trans-isomer)
Insoluble
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
1
1
0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Bixin is an apocarotenoid found in the seeds of the achiote tree (Bixa orellana)[2] from which it derives its name. It is commonly extracted from the seeds to form annatto, a natural food coloring, containing about 5% pigments of which 70–80% are bixin.[3]

Applications

Red seeds of the achiote tree
Bixin is one of the colorants used in the snack Cheetos.

Several thousand tons are harvested annually.[4]

Chemical properties

Bixin is unstable. It isomerizes into trans-bixin (β-bixin), the double-bond isomer.[1]

Chemical structure of trans-bixin

Bixin is soluble in fats and alcohols but insoluble in water. Upon exposure to alkali, the methyl ester is hydrolyzed to produce the dicarboxylic acid norbixin, a water-soluble derivative.

Chemical structure of norbixin

References

  1. ^ a b Merck Index, 11th Edition, 1320
  2. ^ Bouvier, Florence; Dogbo, Odette; Camara, Bilal (2003). "Biosynthesis of the Food and Cosmetic Plant Pigment Bixin (Annatto)". Science. 300 (5628): 2089–2091. Bibcode:2003Sci...300.2089B. doi:10.1126/science.1085162. ISSN 0036-8075. JSTOR 3834418. PMID 12829782. S2CID 560600.
  3. ^ Executive Summary Bixin Archived July 21, 2011, at the Wayback Machine, National Toxicology Program
  4. ^ Stringheta, Paulo C.; Silva, Pollyanna I.; Costa, André G.V. (2018). "Annatto/Urucum— Bixa orellana". Exotic Fruits. pp. 23–30. doi:10.1016/B978-0-12-803138-4.00006-X. ISBN 9780128031384.
Categories