Defatting removes the chlorophyll and other non-polar and low polarity constituents. Polyphenols are water soluble metabolites. So in principle, when fat is removed any interfering fatty material will no longer prevent or delay the extraction of aqueous metabolites.

Hello Yahaya, the simple procedures for defeating is for agitation the material with hexane approx 8 hours if is possible to 4°C  and the solid/liquid ratio is 1:5. After to extraction filter the solution and drier the residue in extraction equip. 

Gustavo Valencia del Toro

thank you sir

Definitively deffated process doesn't affect the phenolic compounds because they are more polar, more than that usually this process is used to clean your extracts.

Olga Lock . thank you madam

Defat procedure does not affect the phenolic compounds as defat system use nonpolar organic solvents like hexane, petroleum ether which do not take phenolic compounds. Moreover, the phenolic compounds are extracted using polar solvents like methanol, ethanol, ethyl acetate, acetone, and water.

Mohammad Khorshed Alam thank you sir