The relationship of flavonoids or polyphenols content versus antioxidant activity is not necessarily a linear relationship or a high content of polyphenols and these not necessarily be bioavailable and bioactive or represent high levels of antioxidant activity. And conversely you can have fewer polyphenols or flavonoids and these have a high biodiponibilidad and therefore express high levels of antioxidant activity. It is recommended for the type of test you're doing, make cromatrográficos profiles that really show you the most abundant polyphenolic compounds and therefrom with the results of antioxidant activity to determine whether the results of higher antioxidant activity correspond to the most abundant polyphenolic analytes, if this is the case you will have the relationship you want. Otherwise it will serve to establish synergistic relationships between compounds that favor greater antioxidant activity.

Regards,

Yasmin Perez Lopera

[email protected]

www.aoxlab.com

you can use a bioguided methods by antioxydant screening

regards

 Dear / Abusufyan Shaikh

From our  researches, we  found that the methanolic extract of whole plant are usually  give the highest total phenolic contents(TPC) (mg /g extract)  and total flavonoid contents  (TFC)( mg /g extract) of plant  as compared to other solvent fractions. The flavonoid/ phenolic ratio differ from plant to another but usually 1/2 ,this means that  the more phenolic compounds the higher antioxidant effects. A significant but marginal positive correlation was found between TPC and EC50 values for DPPH, hydroxyl, phosphomolybdate and ABTS, whereas another weak and positive correlation was determined between TFC and EC50 values for superoxide anion and hydroxyl radicals.

Please Revise this article:

http://www.biomedcentral.com/1472-6882/12/221

If  concentration of flavonoid contents is more then it means the plant is having excellent antioxidant activity.

Dear all,

Thank you very much for your valuable inputs.