New uses for cow parsley

Cow parsley (Anthriscus sylvestris) is a rhizomatous perennial plant whose white umbrella-shaped flower heads fill hedgerows and roadsides from May to July, emitting a distinctive odour evocative of springtime. Its ability for rapid spread through rhizomes and seed production has made it an invasive pest in some parts of the world.

The leaves and rhizomes are edible, but not palatable, and its only use in folk medicine was as a tonic and to cleanse the kidneys and gall bladder. Its unpopularity may be due to the poisonous nature of other species of wild parsley similar in appearance, including hemlock and the hogweeds. The dried roots are used, mixed with other species, as a haematinic and tonic in Chinese medicine, but until recently it has been largely ignored in the west.

Researchers at the University of Padova in Italy studied several plant species when looking for a source of the lignin podophyllotoxin, which as a result of recent research has shown promise as a starting compound for the production of several semisynthetic anticancer drugs.

It was formerly extracted from the roots of several species of may-apple of the genus Podophyllum, for use in wart paints, but the extraction is low-yielding. It was discovered that the entire Anthriscus sylvestris plant is a source of the closely related deoxypodophyllotoxin, with highest concentrations in the roots. In vitro studies in South Korea have shown that deoxypodophyllotoxin itself inhibits tubulin polymerisation and induces cell cycle arrest, followed by cell death, in cervical carcinoma cells.

It is hoped that cow parsley could provide a cheap and abundant alternative source of these lignins.