Dear Khadidja, from your data you can determine the relationship between antioxidant activity (maybe it is DPPH assay) and concentration of extract by interpolation on graphpad. From the linear equation you can find the IC50 microgr/ml to present the antioxidant potential of the extract.

For finding correlation between TPC, TFC and antioxidant activity you have to examine different extracts, maybe from different plant parts or even different plant, or extracts obtain using different solvents. You can read my paper attached below.

Best regards

Dear khadidja,

If you want to make a correlation between the amount of TPC and TFC and the antioxidant activity this is possible using some statistical analysis. However before starting to introduce the values you need to make a table where you put all your values of TPC, TFP and IC50 of the antioxidant activity tests (For exemple :DPPH, RP, B-carotene....) once you have one value for each parameter you can perform Pearson’s correlation analysis between the antioxidant activity and the quantification values that you found with a 95% significance level.

You can see my article :

Phenolic compounds characterization by LC-DAD- ESI/MSn and bioactive properties of Thymus algeriensis Boiss. & Reut. and Ephedra alata Decne

DOI: 10.1016/j.foodres.2018.08.041

Good luck

Dear,

Please read the article. I think it would be helpful.....

for on sample you can't do correlation

If you want to make a correlation between the amount of TPC and TFC and the antioxidant activity use correlation scatter plot matrices with Pearson correlation coefficients- assuming you have enough data to work with

Dear Khadidjah,

Your data is not sufficient to perform correlation analysis. You may use the other parts of the plant like fruit, leaf, root, flower, bark.

With just one value it's impossible. You need differents values to determine correlation