What do you mean by molecular weight forr  herbal extract... ?

My understanding is that the molecular Wight can be determined only for a single pure compound could be by using of LC/MS QTOF for example. . But surely the plant extract is a combination of several compounds. .. 

Rasha Saad

of course you are right, but I specifically wanted to know if there any pharmacopoiea reference or any other protocol to justify the medicinal specification of the plant extract i.e. the main active chemical constituent which is responsible for the clinical effect. There  must have the molecular formula to ensure the therapeutic claim by any lab work. Actually herbal or ayurvedic monographs can be useful in this case, but they don't have chemical formula. I need some specific chemical information on this plant. 

Thanks. 

Herbal extracts and similar preparations are generally non-standardised from a scientific perspective. In real circumstances the alkaloid, terpenoid or polyketide content of a plant will vary greatly depending on rainfall, temperature variation, soil quality etc. So no, there is no protocol for the specifications of herbal drugs. The exact contents cannot be regulated, but the method of production may be specified in a research context.

Psyllium has multiple components but is mainly used as a source of mucilage, a mixture of polysaccharides that aid in digestive processes acting as a soluble fibre. Various sterols, terpenes, and alkaloids have also been reported as being isolated from psyllium extracts.

Therapeutic claims are often made for herbal extracts, without any standardisation.

Thanks Eric B. J. Harris.