Annatto, Bixin, Norbixin is a red-orange coloring inserted in the list of food additives with the number E160b and it is extracted from the plant Bixa orellana L. originating in the Amazon.

The name describes the structure of the molecule:

• E160b is a code used in Europe to indicate specific food additives. The "E" stands for Europe and the following numbers classify the type of additive. The E100-E199 range includes all dyes and E160 refers specifically to dyes derived from natural sources.
• Annatto is the common name of the additive E160b. Annatto is an orange-reddish dye derived from the seed of the achiote tree (Bixa Orellana). It is used to color food, cosmetics and textiles. In food, it is often used to give a yellow or orange color to products such as butter, cheese and margarine.

The synthesis process takes place in several stages:

• Preparation. Seeds are cleaned and dried.
• Extraction. The dye is extracted from the seeds using an oil or water process. The seeds are immersed in the liquid and heated to help release the dye.
• Filtration and purification. The liquid is then filtered to remove seeds and any other solid matter. The resulting liquid contains the colorant annatto.
• Concentration. The liquid is then concentrated, typically by evaporation, to produce a more concentrated dye.
• Formulation. the dye is then formulated in the desired form, such as a liquid or powder, and any additional ingredients are added.

It comes in the form of a reddish or orange powder.

 According to the Regulation (EU) No 2020/0771, Annatto, Bixin, Norbixin is deleted from the Union List and is replaced by two separate Food Additives namely Annatto bixin (E 160b(i)) and Annato norbixin (E 160bii))

The seeds of annatto have been used as a traditional medicine to cure infection as they contain tocotrienol, very close to vitamin E in the δ form (δT3).

Commercial applications 

Food. E160b is used as a food coloring to impart a yellow or orange hue to various products like cheeses, butter, margarine, cereals, and baked goods.

Cosmetics. It can be used as a dye in cosmetic products like lipsticks and eyeshadows.

Personal Care Products. Found in some soaps and lotions to color the product.

Pharmaceutical. Used in some medications as a coloring for capsules and tablets.

Textile. In some cultures, annatto is used as a natural dye for fabrics.

Studies

The aim of this study was to determine whether annatto T3 is effective in attenuating NLRP3 inflammasome activation in macrophages. Results showed that annatto δT3 significantly attenuated NLRP3 inflammasome by decreasing IL-1β reporter activity, IL-1β secretion, and caspase-1 cleavage against lipopolysaccharide (LPS) followed by nigericin stimulation. With regard to mechanism, annatto δT3 1) reduced LPS-mediated priming of the inflammasome and dampened reactive oxygen species production, the second signal required for assembly of the NLRP3 inflammasome in macrophages. This work suggests that annatto δT3 may hold therapeutic potential for delaying the onset of NLRP3 inflammasome–associated chronic metabolic diseases (1).

Annatto-derived tocotrienol up to 600 mg per day for 12 weeks appeared to be safe in postmenopausal osteopenic women, particularly in terms of liver and kidney functions. Tocotrienol supplementation for 12 weeks did not affect body composition, physical activity, quality of life, or intake of macro- and micro-nutrients in these subjects (2).

Metabolic syndrome (MetS) is associated with osteoporosis due to the underlying inflammatory and hormonal changes. Annatto tocotrienol has been shown to improve medical complications associated with MetS or bone loss in animal studies. This study aimed to investigate the effects of annatto tocotrienol as a single treatment for MetS and osteoporosis in high-carbohydrate high-fat (HCHF) diet-induced MetS animals. Three-month-old male Wistar rats were randomly divided into five groups. The baseline group was euthanized at the onset of the study. The normal group received standard rat chow and tap water. The remaining groups received HCHF diet and treated with three different regimens orally daily: (a) tocopherol-stripped corn oil (the vehicle of tocotrienol), (b) 60 mg/kg annatto tocotrienol, and (c) 100 mg/kg annatto tocotrienol. At the end of the study, measurements of MetS parameters, body compositions, and bone mineral density were performed in animals before sacrifice. Upon euthanasia, blood and femur of the rats were harvested for the evaluations of bone microstructure, biomechanical strength, remodelling activities, hormonal changes, and inflammatory response. Treatment with annatto tocotrienol improved all MetS parameters (except abdominal obesity), trabecular bone microstructure, bone strength, increased osteoclast number, normalized hormonal changes and inflammatory response in the HCHF animals. In conclusion, annatto tocotrienol is a potential agent for managing MetS and osteoporosis concurrently. The beneficial effects of annatto tocotrienol may be attributed to its ability to prevent the hormonal changes and pro-inflammatory state in animals with MetS (3).

Following a request from the European Commission to EFSA, the EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS) was asked to re‐evaluate the safety of annatto extracts, bixin‐based and norbixin‐based, when used as a food additive and to evaluate the safety of aqueous‐processed bixin (Annatto E); solvent‐extracted bixin (Annatto B); alkali‐processed norbixin, acid‐precipitated (Annatto F); alkali‐processed norbixin, not acid‐precipitated (Annatto G) and solvent‐extracted norbixin (Annatto C) with the view to replace the currently authorised annatto extracts (E 160b). Given: (a) that read‐across among the five bixin‐ and norbixin‐based annatto extracts was feasible; (b) the availability of adequate 90‐day toxicity studies with Annatto B, C, E and F; (c) the absence of concern for mutagenicity, carcinogenicity, reproductive and developmental toxicity of Annatto B, C, F and G, whereas the mutagenicity of Annatto E is equivocal, the Panel concluded that the safety of the currently authorised solvent‐extracted bixin and norbixin (E 160b(i)), alkali‐extracted annatto (E 160b(ii)) and oil‐extracted annatto (E 160b(iii)), with the specifications defined in Commission Regulation (EU) No 231/2012, could not be assessed due to the lack of data, both in terms of identification and toxicological studies; solvent‐extracted bixin (Annatto B), solvent‐extracted norbixin (Annatto C), alkali‐processed, acid‐precipitated norbixin (Annatto F) and alkali‐processed, not acid‐precipitated norbixin (Annatto G and its norbixin salts) should comply with the specifications as recommended by the Panel. The toxicological database is sufficient to derive an acceptable daily intake (ADI) of 6 mg bixin/kg body weight (bw) per day and an ADI of 0.3 mg norbixin/kg bw per day. Exposure estimates for bixin were below the ADI for all population groups and for all refined exposure scenarios, including for the extension of use. For norbixin, exceedance was observed for the extension of use at the 95th percentile for some population groups (4).

• Molecular Formula: C₂₄H₂₈O₄    C₂₅H₃₀O₄
• Molecular Weight  380.484
• CAS: 626-76-6  6983-79-5  542-40-5
• EINECS 215-735-4  

Synonyms : (2E,4E,6E,8E,10E,12E,14E,16Z,18E)-4,8,13,17-tetramethylicosa-2,4,6,8,10,12,14,16,18-nonaenedioic acid  -  1343-85-7  -  1393-63-1  -  6,6'-Diapo-psi,psi-carotenedioic acid, 9-cis-  -  626-76-6  -  6PQP1V1B6O  -  79586-44-0  -  8015-67-6  -  9-Cis-6,6'-diapo-psi,psi-carotenedioic acid  -  AC1O6WX0  -  alpha-Norbixin  -  AN-49143  -  Annatto coloring dye - Annatto extract  -  Annatto pigment  -  Annotta extract  -  Bixa orellana extract  -  CCRIS 3651  -  CHEMBL1420783  -  CI 75120  -  cis-Norbixin  -  DTXSID60274023  -   FEMA No. 2103  -  FEMA No. 2104  -  HSDB 7976  -  LS-2208  -  MH1WZE9GBD  -  Natural orange 4  -  NCGC00091523-01  -  SC-23249  -  SCHEMBL340220  -  UNII-6PQP1V1B6O  -  UNII-MH1WZE9GBD  -  W-108218  -  ZINC8582047

References_____________________________________________________________________

(1) Buckner T, Fan R, Kim Y, Kim J, Chung S. Annatto Tocotrienol Attenuates NLRP3 Inflammasome Activation in Macrophages.  Curr Dev Nutr. 2017 May 31;1(6):e000760. doi: 10.3945/cdn.117.000760. eCollection 2017 Jun.

(2) Shen CL, Wang S, Yang S, Tomison MD, Abbasi M, Hao L, Scott S, Khan MS, Romero AW, Felton CK, Mo H. A 12-week evaluation of annatto tocotrienol supplementation for postmenopausal women: safety, quality of life, body composition, physical activity, and nutrient intake.  BMC Complement Altern Med. 2018 Jun 28;18(1):198. doi: 10.1186/s12906-018-2263-0.

(3) The safety of annatto extracts (E 160b) as a food additive - EFSA Journal 2016;14(8):4544 [87 pp.].