Berzelius was the first person to make the distinction between organic compounds (those containing carbon), and inorganic compounds. In particular, he advised Gerardus Johannes Mulder in his elemental analyses of organic compounds such as coffee, tea, and various proteins. The term protein itself was coined by Berzelius, in 1838, after Mulder observed that all proteins seemed to have the same empirical formula and came to the erroneous conclusion that they might be composed of a single type of very large molecule. The term is derived from the Greek, meaning "of the first rank", and Berzelius proposed the name because proteins were so fundamental to living organisms.
In 1808, Berzelius discovered that lactic acid occurs in muscle tissue, not just in milk.
The term biliverdin was coined by Berzelius in 1840, although he preferred "bilifulvin" (yellow/red) over "bilirubin" (red).