办事指南

Deck the halls

点击量:   时间:2019-03-08 10:15:06

By Andy Coghlan THAT prickly symbol of Christmas, the holly bush, might contain life-saving substances. Over the past 18 months chemists in Ireland have extracted several compounds from the European holly bush that could one day treat diseases such as cancer. Holly extracts have been prescribed as folk remedies in Europe for centuries to treat everything from dizziness and hypertension to cancer. “These are still used in parts of Spain and Turkey,” says Myles Keogh at the Galway-Mayo Institute of Technology in Galway. Although local holly varieties are under scrutiny by chemists in China and Japan, the properties of the European holly bush (Ilex aquifolium) had been ignored by researchers, so Keogh and his colleagues decided to investigate. “There was lots of it growing wild where I live,” he recalls, “so I thought I’d have a look.” The team has now isolated several potential medicinal chemicals. Although their potency has yet to be tested, Keogh hopes some might be valuable because other substances from the same chemical families have found a place in medicine. From holly-bush roots Keogh has isolated three saponins. Similar compounds in soya beans and yams have been linked with resistance to cancer, while others have been tested as adjuvants that strengthen the immunological effects of vaccines. Holly’s saponins are slightly unusual in that they each carry a pair of sugars. “The sugars make them more permeable, so they might get into cells more easily,” says Keogh. More recently, the team has isolated compounds called triterpenes from the bush’s bark. They are already under evaluation for medicinal properties. Betulinic acid, a triterpene from birch bark, is being tested against skin cancer. Keogh says the triterpenes in holly are tethered to fatty acids, and are unusually abundant. They make up about 20 per cent of the bark’s weight,