Aims:

This study aimed to characterize and compare the antioxidative potential of extracts obtained by infusion, decoction, tincture, aqueous extraction, and hydro-ethanolic maceration from the aerial parts of Polygonum acre H.B.K., which has been traditionally used in herbal preparations, for different purposes. The therapeutic benefits are attributed to phenolic compounds and their antioxidant properties.

Methods:

All extracts were characterized considering their quantitative content of the total phenolics, flavonoids, condensed and, hydrolysable tannins, by colori-metric methods. EHW-PA was selected for HPLC analysis as it showed a higher yield (10.58 % w/m) and a phenolic content > 200 mg GAE/g dry extract. The phenolic profile showed a chromatogram with 20 peaks, and the presence of gallic acid, rutin, and quercetin was verified by comparison with the retention times of standard compounds. The antioxidant activities were determined by ABTS capture test, ferric reducing antioxidant power test (FRAP), and the superoxide anion scavenging test.

Results:

Tinctures showed a higher average content of phenolic compounds, present mainly as flavonoid content. A significant correlation coefficient was observed between the total phenolic content and its antioxidant activity, determining by ABTS and FRAP assays. Differently, a low to moderate correlation between the flavonoid content and antioxidant activity was verified.

Conclusion:

This study reinforces the ethnopharmacological relevance of the Polygonum genus and could contribute to the scientific basis for the use of P. acre preparations.