**8.8 Chemical fingerprinting**

A chemical fingerprinting is a unique pattern just like human fingerprints which is unique for every individual, which indicates the multiple chemical markers within a sample [49]. The European Medicines Agency (EMEA) defines chemical markers as chemically defined constituents, or group of constituents of herbal medicinal product which are of interest, regardless whether they possess any therapeutic activity [50]. Such chemical markers are critical in identification and authentication of the plants from which they are derived. The quantity of a chemical marker is proportional to the quality of herbal medicine. The study of chemical markers is applicable to many research areas, including authentication of genuine species, search for new resources or substitutes of raw materials, optimization of extraction and purification methods, structure elucidation and purity determination.
