Quinine was first isolated in 1820 from the bark of the cinchona tree.
Quinine occurs naturally in the bark of the cinchona tree. Quinine was first isolated in 1820.
Quinine was first isolated in 1820. Quinine occurs naturally in the bark of the cinchona tree.
Quinine was first isolated in 1820. Quinine occurs naturally in the bark of the cinchona tree.