Brazzein

---

title: "Brazzein" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["sugar-substitutes", "plant-proteins", "cysteine-rich-proteins"] description: "Protein" topic_path: "general/sugar-substitutes" source: "https://en.wikipedia.org/wiki/Brazzein" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Protein ::

::data[format=table title="Infobox nonhuman protein"]

Field	Value
Name	Brazzein
caption	Solution NMR structure of the brazzein protein.
image	Brazzeinmj.png
Symbol	MONA_DIOCU
UniProt	P56552
PDB	1BRZ
Organism	Pentadiplandra brazzeana
::

| Name = Brazzein | caption = Solution NMR structure of the brazzein protein. | image = Brazzeinmj.png | width = | HGNCid = | Symbol = MONA_DIOCU | AltSymbols = | EntrezGene = | OMIM = | RefSeq = | UniProt = P56552 | PDB = 1BRZ | PDB_supplemental = | ECnumber = | Chromosome = | Arm = | Band = | LocusSupplementaryData = | Organism=Pentadiplandra brazzeana

Brazzein is a sweet-tasting protein that occurs naturally in oubli (Pentadiplandra brazzeana), a fruit native to the Atlantic coastal areas of Central Africa. Brazzein was first isolated in 1994 by scientists at the University of Wisconsin–Madison. It is roughly 500 to 2000 times sweeter than sucrose.

Brazzein is found in the extracellular region of oubli fruit, in the pulp tissue surrounding the seeds. After pentadin, discovered in 1989, brazzein is the second sweet-tasting protein discovered in the Oubli fruit.

Like other sweet proteins discovered in plants, such as monellin and thaumatin, brazzein is extremely sweet compared to commonly used sweeteners. The fruit tastes sweet to humans, monkeys, and bonobos, but gorillas have mutations in their sweetness receptors so that they do not find brazzein sweet, and they are not known to eat the fruit.

Traditional use

The oubli plant (from which the protein was isolated) grows in Gabon and Cameroon where its fruit has been consumed by apes and local people over history. Due to brazzein and pentadin, the berries of the plant have exceptional sweetness. Locals call the berries "oubli" (French for "forgot") in their vernacular language because their taste is said to encourage nursing infants to forget their mother's milk, as once babies eat them, they may forget to return to their mothers.

Protein structure

The monomer protein, consisting of 54 amino acid residues, is the smallest of the sweet proteins with a molecular weight of 6.5 kDa. The amino acid sequence of brazzein, adapted from the Swiss-Prot biological database of protein, is as follows:

The structure of brazzein was determined by proton nuclear magnetic resonance (NMR) at a pH of 5.2 and 22 °C. Brazzein has four evenly spaced disulfide bonds and no sulfhydryl groups.

3D analysis of brazzein showed one alpha-helix and three strands of anti-parallel beta sheet. This is not superficially similar to either of the other two sweet-tasting proteins, monellin and thaumatin.

However, a recent 3D study shows that these three proteins possess similar "sweet fingers" believed to elicit the sweet taste.

Residues 29–33 and 39–43, plus residue 36, as well as the C-terminus were found to be involved in the sweet taste of the protein. The charge of the protein also plays an important role in its interaction with the sweet taste receptor.

Based on this knowledge a synthesised improved brazzein, called pGlu-1-brazzein, was reported to be twice as sweet as the natural counterpart.

Sweetness properties

On a weight basis, brazzein is 500 to 2000 times sweeter than sucrose, compared to 10% sucrose and 2% sucrose solution respectively.

Its sweet perception is more similar to sucrose than that of thaumatin, with a clean sweet taste, lingering aftertaste, and slight delay (longer than aspartame) in an equi-sweet solution.

Brazzein is stable over a broad pH range from 2.5 to 8, and is heat stable at 98 C for 2 hours.

As a sweetener

Brazzein represents an alternative to available low-calorie sweeteners. As a protein, it is safe for diabetics. It is also very soluble in water (50 mg/mL).

When blended with other sweeteners, such as aspartame and stevia, brazzein reduces side aftertaste and complements their flavor.

Its taste profile is closer to sucrose than other natural sweeteners (apart from thaumatin). Unlike other sweet-tasting proteins, it can withstand heat, making it more suitable for industrial food processing.

Papers have been published showing it can be made in a laboratory using peptide synthesis and recombinant proteins were successfully produced via E. coli.

The Texas companies Prodigene and Nectar Worldwide were among the licensees to use Wisconsin Alumni Research Foundation patents on brazzein, and genetically engineer it into maize. Brazzein then can be commercially extracted from the maize through ordinary milling. Approximately one ton of maize yields 1-2 kilograms of brazzein. It can also be engineered into plants like wheat to make pre-sweetened grains, e.g. for cereals.

A company was formed to bring it to market as a sweetener in 2008, which initially said it would start selling the product by 2010 once it obtained agreement from the FDA that its brazzein was generally recognized as safe (GRAS).

In 2024, the brand Oobli received the first GRAS certification from the FDA, with no potential concerns for consumption being raised.

References

References

1. (June 1998). "Solution structure of the thermostable sweet-tasting protein brazzein". Nat. Struct. Biol..
2. (November 1994). "Brazzein, a new high-potency thermostable sweet protein from Pentadiplandra brazzeana B". FEBS Lett..
3. (1989). "Isolation and characterization of pentadin, the sweet principle of Pentadiplandra brazzeana Baillon". Chem. Senses.
4. (2004). "Biopolymers: Polyamides and Complex Proteinaceous Materials II". Wiley-VCH.
5. (Jul 2016). "Potential arms race in the coevolution of primates and angiosperms: brazzein sweet proteins and gorilla taste receptors". American Journal of Physical Anthropology.
6. (Jul 23, 2016). "Gorillas may have evolved a way to beat a cheating berry plant". New Scientist.
7. (1988). "Sucres et "faux sucres" de la forêt équatoriale : évolution et perception des produits sucrés par les populations forestières d'Afrique". Journal d'Agriculture Tropicale et de Botanique Appliquée.
8. [http://www.expasy.org/uniprot/P56552 UniProtKB/Swiss-Prot database entry #PP56552]
9. (July 1996). "Synthesis and characterization of the sweet protein brazzein". Biopolymers.
10. (June 2004). "Interaction of sweet proteins with their receptor. A conformational study of peptides corresponding to loops of brazzein, monellin and thaumatin". Eur. J. Biochem..
11. (April 2000). "Sweetness determinant sites of brazzein, a small, heat-stable, sweet-tasting protein". Arch. Biochem. Biophys..
12. (2000). "Modelling the sweetness response using time-intensity data". Food Quality and Preference.
13. Birch, Gordon Gerard. (2000). "Ingredients Handbook - Sweeteners (Ingredients Handbook Series)". Leatherhead Food Research Association.
14. (2005). "Brazzein a Small, Sweet Protein: Discovery and Physiological Overview". Chem. Senses.
15. "Brazzein sweetener".
16. (April 2000). "Efficient production of recombinant brazzein, a small, heat-stable, sweet-tasting protein of plant origin". Arch. Biochem. Biophys..
17. (24 June 2008). "New sweetener to hit market hungry for alternatives". FoodNavigator-USA.com.
18. "Oobli Becomes Receives FDA "No Questions" Letter for Novel Sweet Protein Produced via Precision Fermentation {{!}} Prepared Foods".

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::