Brazzein

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.