MAKING DRUGS

THIS week: Hyaluronic acid

COCKERELS’ and chickens’ combs, the fleshy growth on the top of their heads, are a rich source of hyaluronic acid, a sugary compound used to lubricate and cushion arthritic joints.

It is also added to contact lens solutions and used cosmetically to plump up sagging cheeks and sunken eyes.

The compound can also be extracted from sheep joints and hooves and from the outer layer of a bacterium that lives on horses, before being modified for use in humans, says David Kroll, a professor of pharmacology. The red fleshy crests on cockerels’ and chickens’ heads, however, are one of the world’s richest sources. ‘It’s probably one of the few parts of the bird you wouldn’t eat, so it’s a great idea to use it,’ says Professor Kroll, of the University of Colorado Denver, in the US.