With the spread of bird flu prompting fears of an epidemic or even pandemic that could kill humans by the million, a Chinese spice hitherto associated with the pleasures of aperitifs has suddenly assumed key medical significance.

epidemic or even pandemic that could kill humans by the million, a Chinese spice hitherto associated with the pleasures of aperitifs has suddenly assumed key medical significance." hspace=0 src="/images/404/404.jpg" align=baseline border=1> The Star Anise, a rare herb grown in China used to flavour duck dishes and treat infants for colic, on sale together with other spices at a market in Nanning, South China's Guangxi Zhuang Autonomous Region October 25, 2005. [AFP]

Harvested in China and Vietnam and used as a spice, it provides flavouring for candies, pastis drinks and tobacco.

But it also has a key pharmaceutical asset - shikimic acid, described by experts as the world's only weapon against bird flu.

Star anise, the dried, star-shaped multiple fruit of a small oriental tree which is a member of the magnolia family, is a traditionalingredient of oriental cuisine with its pungent, liquorice-like flavour.

It also serves as the main flavouring of the liqueurs Pernod and Anisette.

But its medical significance had already been noted before bird flu arrived, including potential cancer-fighting properties.

Now it has sprung to new prominence as a chief source of shikimic acid, a vital ingredient of Tamiflu, one of the rare anti-viral drugs that has proved effective against the lethal H5N1 strain of bird flu which has infected 118 people in Asia since late 2003 and killed more than 60 people.

"From this one plant you can make both a drink -- pastis -- and a pharmaceutical product, Tamiflu," said Albert Elgrissy, communications director for the pastis maker Ricard in Marseille.

"To make pastis, Pernod Ricard adds anethol -- an essential oil extracted from star anise -- in a ratio of two to one thousand to liquorice, sage, lavender and other herbs of Provence."

"Meanwhile the Swiss Roche laboratories extract shikimic acid from the plant's woody part. This acid is a molecule needed to produce Tamiflu."

"Thirteen grams (0.46 ounces) of star anise are required to produce 10 Tamiflu capsules prescribed to treat a person contaminated with avian flu," Elgrissy explained.

But shikimic acid does not come cheap. The price varies between 200 and 250 dollars (166-207 euros) per kilogram, the equivalent of between 90 and 113 dollars per pound.

But for extra pure quality, the price soars to as high as 50 dollars a gram, the equivalent of 1,555 dollars an ounce, according to the website of Yusuf Hamied, head of Cipla, an Indian generic drugs manufacturer.

With its distinctive flavour, star anise has been closely linked for centuries with Asian cooking. Every year 30,000 tonnes of the fruit are used across the world for recipes for Vietnamese soup and pork Chinese-style.

China is the world's main producer of star anise, annually exporting 1,000 tonnes of anethol, the oil extract from the flower's dried pistil.

In the West, anethol is used in the manufacture of various consumer products including candies, biscuits, perfumes and hygiene products such as toothpaste and soap.

"The tobacco industry also uses star anise together with rum for example, to give texture and flavour to cigarettes," said Elgrissy.

Pernod Ricard uses 160 tonnes of anethol annually, making it one of France's major users of the product.

"For pastis we use star anise but sometimes also essential oil of fennel which also discharges an anise odour."

Elgrissy said fennel had served as an alternative to star anise "when the Chinese organised a star anise shortage in the 1970s to provoke a spectacular price rise."

In 2001, French authorities banned use of star anise in drugs and herb teas following reported cases of convulsion after infusions of herbal tea had been consumed.

Japanese star anise containing toxic alkaloids was later banned from being merchandised in any product in France.

But the pharmaceutical industry says it is satisfied that the Chinese version does not contain any such health risks.