Coriander contains 'green' nylon clue

Scientists searching for an environmentally-friendly way of producing nylon may have found the answer in the coriander plant.

Nylon is made by reacting benzene with nitric acid and, as the textile is produced nitrous oxide is given off - which is both a greenhouse gas and helps to destroy the ozone layer.

But researchers at the John Innes Institute in Norwich are working with a family of vegetables, including carrot, parsley and dill, whose seeds contain a chemical (petroselinic acid) that can easily be split in two.

One half is the main part of engineering nylon. The other half can be used by the detergent industry. The only by-product is water. Ray Mathias, a project leader at the institute, said there are two ways to exploit the discovery.

One would be to fill our fields with coriander plants, because their seeds are rich in the chemical. "We would be converting a semi-wild spice crop into an arable oil seed crop," he said. He is crossing plants to try to make a robust coriander plant and says "we have every indication that it won't be a problem".

The other option is to isolate the gene in coriander that produces petroselinic acid and transplant it into the rape plant, which is already grown widely in the United Kingdom. One problem with this approach is that it would increase rape cultivation. This is bad for agriculture, which needs to use a variety of crops in order to keep the soil balanced, and so there would be a limit to the acreage planted.

Scientists at the institute, led by Denis Murphy, have isolated the genes and transferred them into the rape plant. They will soon be searching their new crop for plants that are producing the acid.

Dr Mathias predicted that the first approach could produce "something that works in the field" in five to eight years. The genetic approach could lead to rape plants that produce petroselinic acid within five years.