BOSTON — Your discarded Christmas tree might help researchers fight the flu. Some evergreen tree leaves bristle with shikimic acid, an important starter material for the antiflu drug Tamiflu, scientists reported August 26 at the American Chemical Society’s fall meeting. The compound is a precursor for many plant molecules, including amino acids and some alkaloids.
Shikimic acid makes up about 3 percent of the dry weight of pine and spruce needles, and is easily extracted with water and ethanol, Nilmini Gedivinne and her colleagues at the University of Maine in Orono discovered. While drug makers have figured out how to engineer E. coli bacteria to make shikimic acid, the majority of the compound still comes from Illicium verum, or star anise, a small tree native to Asia that bears a hard, dry, star-shaped fruit. When bird flu proliferated in 2005, the main bottleneck in the supply of Tamiflu was a shortage of star anise.