An extract from the common curry spice turmeric could help cure cancer, researchers believe.

Curcumin, an extract of the root turmeric, has the ability to kill off cancer cells which are resistant to chemotherapy, scientists at the University of Leicester think.

They have been using tissue from tumours of bowel cancer patients to test their theory.

Dr Karen Brown, of the Department of Cancer Studies and Molecular Medicine, said: "Tumours are made up of different types of cells and some are resistant to chemotherapy treatment which, in some cases, causes the tumours to grow back.

"We aren't yet treating patients but looking at cells to see how effective curcumin is in killing off the resistant stem cells."

Laboratory research shows that curcumin, when combined with other chemotherapy drugs, has the ability to destroy the resistant cells. Clinical trials have yet to be carried out.

Dr Brown said: "It is a big step but it is still likely to take at least five to 10 years before it becomes part of treatment."

Dr Lynne Howells, a senior research fellow at the university who is leading the study, said: "We are primarily looking at treatment for bowel cancer where the cancer has spread to the liver.

"However, the work could have much wider implications in the treatment of other cancers."

Researchers now hope to carry out a study with patients suffering from bowel cancer to test the safety and quantities of curcumin which should be given.

Dr Howells said: "We will start with a small dose – the equivalent contained, for example, in a normal curry. We are now hoping to give increasing amounts to patients receiving chemotherapy."

But she warned patients should not rush out and have a curry thinking it will do the trick.

"We don't yet know all the effects of circumin and the amounts that should be given, she said.

"All this does need to be done in a controlled environment."

The work has won £75,000 worth of funding over the next three years from Leicestershire charity, Hope Against Cancer ,which Dr Howells said "allows us to expand our promising research".

The charity was founded in 2002 by the late Allison Wilson, a former High Sheriff of Leicestershire, after she was diagnosed with cancer and realised funding was needed to develop care in Leicestershire and Rutland.

Wendi Stevens, from the charity, said: "It is thanks to a team of dedicated volunteers and fund-raisers that we are able to fund exciting research such as this in Leicester."