The experimental process of TA IL-DLLME method.(SHI Yanping et al.)

 

Research chemists at the North-Western Plant Resources have developed new methods for extracting the bioactive components of the Chinese herbal medicine, Radix et Rhizoma Rhei, also known as rhubarb root. They have also developed a technique for extracting residual pesticides from it.

The five bioactive components are anthraquinones, naturally occurring laxatives: emodin, chrysophanol, rhein, aloe-emodin, physcion. They are colourful, from yellow to orange and red. Their combination gives rhubarb its distinctive colour.

One of the new techniques reduces the experimental cost of extraction as well as the consumption of organic solvent, harmful to people and the environment.

Another technique – ultrasonic cell grinder extraction -- reduces the extraction time and increases yield, making it a better alternative to more conventional methods.

The third technique detects residual organochlorine pesticides, commonly found in many Chinese herbal medicines. They successfully extracted seven such pesticides from a sample of Radix et Rhizoma Rhei. and believe the approach can be used to sample residues in other herbs.

The research has received support from National Key Technology Research and Development Program of the Ministry of Science and Technology of China and National Natural Science Foundation of China.

Its findings have been published in Talanta (2010, 82, 1010–1016), Anal. Bioanal. Chem. (2010, 398, 1501–1508) and J. Sep. Sci.( 2010, 33, 1730–1738).

Abstract of the paper published in Talanta

Abstract of the paper published in Anal. Bioanal. Chem.

Abstract of the paper published in J. Sep. Sci.