Polyphenol quantification on dipsacus laciniatus and armoracia rusticana from romanian flora

In recent years, the polyphenolic compounds profile of plants has been intensively studied. These compounds protect the body against oxidative stress and certain diseases such as diabetes and cancer, where the antioxidant efficiency of the defence system is low. The plant material (harvested from Romania) was analysed for polyphenols and flavonoids using thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) coupled with photo diode array and mass spectrometer. The polyphenols/flavonoids (caffeic acid, chlorogenic acid, p-coumaric acid, protocatechuic acid, rutin and quercetin) were identified and quantified in different part of the plants (flower, leaf, stem and roots for Dipsacus laciniatus and both roots and leaves for Armoracia rusticana). The least amount of polyphenols were found to be as expected in the root part of Dipsacus laciniatus. This was also sustained by the further UHPLC-MS analysis. The results revealed that the flower extract has the highest radical scavenging activity with 87.43% followed by the leaf extract with 86.63%, the stem extract with 83.54% and the root extract with 78.17%. Higher concentrations of p-Coumaric acid and ferulic acid were identified in the Armoracia rusticana samples whereas the Dipsacus laciniatus samples contained higher concentrations of both protocatechuic acid and chlorogenic acid. The results of the present study revealed that the methanolic extracts of both Dipsacus laciniatus and Armoracia rusticana , can be considered an effective source of antioxidant compounds.