A new drug to treat Alzheimer's disease that uses flavonoids found and extracted by Chinese researchers from cotton petals has entered clinical trial.

Researchers at Xinjiang Technical Institute of Physics and Chemistry under the Chinese Academy of Sciences said this week that they had discovered flavonoids capable of improving animals' learning ability in a study that began in 2003.

These flavonoids were found to improve the memory of mice with dementia and that of naturally aged mice.

Researchers then identified the 20 flavonoid compounds in the petals and made tablets that can produce a similar effect at small dosages.

The research institute signed a deal with a pharmaceutical marker to apply the research finding.

The white and pink cotton-petal blossom bloom before the cotton bolls. Xinjiang is a major cotton production base in China. Previously these petals were discarded but after their medicinal property were uncovered, they now sell for around 15 yuan per kilogram in the market. (Xinhua)