China: Rare yew tree containing compound used against cancer found in Hunan

An endangered tree species of the Taxus Chinensis family, or Chinese yew, believed to be more than 1,300 years old, has been found during a census of ancient trees in central China's Hunan Province. The rare find can prove to be beneficial for the medicinal research industry as the compound paclitaxel or taxol can be extracted from the species which is used in the treatment of cancer.

The tree was found in Shunhuangshan National Forest Park in Dong'an County in the city of Yongzhou and has a height of 35 metres and a diameter of 2.2 metres. There are two sub-trees on both sides of the yew tree and all three ancient trees have been well preserved by local villagers, Xinhua reported.

Taxol only constitutes 0.01-0.03% of the dry weight of the inner bark of the yew tree. This means that vast numbers of the tree are needed to isolate even small amounts of the drug. Also, researchers believe the Chinese yew species that has been found may be quite different from the Pacific yew or European yew generally used in taxol extraction.

Since a large number of trees from the species have already been felled to extract taxol, the tree is now under first-grade national protection for endangered plants. The process during extraction of taxol from the bark of the yew kills the tree. The tree can, however, be used in many other ways under special protection laws.

The drug paclitaxel is on the World Health Organization's List of Essential Medicines. The list contains the most important medications needed in a basic health system. Although over the years methods have been devised to clinically derive the compound, concerns still linger over the environmental impact of the drug's initial sourcing from the slow-growing yew trees.