Phytochemical screening, quantitative analysis and antioxidant activity of Asteriscus imbricatus and Pulicaria mauritanica organic extracts

Asteriscus imbricatus and Pulicaria mauritanica plants (Asteraceae) are well known for their medicinal value in Souss-Massa region near Agadir city in Morocco. However, several studies are needed to explain scientifically their efficacy. In this regard, different experiments are conducted on various organic extracts of these plants. The solvents used for the extraction are petroleum ether, chloroform, ethyl acetate and methanol. We performed a phytochemical characterization of flavonoids, terpenes and alkaloids compounds. We have quantified the total phenolic, total flavonoids and condensed tannins. We have also evaluated the antioxidant activity of these extracts. This study revealed the presence of flavonoids in the four extracts while the terpenes are present in petroleum ether and chloroform extracts for both plants species. Alkaloids are present only in A. imbricatus chloroform and ethyl acetate extracts. P. mauritanica is rich in flavonoids and polyphenols: P. mauritanica ethyl acetate extract contain 72.88±0.21 mg GE/g DWE of total polyphenols and 38.95±0.75 mg QuE/g of DWE of flavonoids. However, A. imbricatus ethyl acetate extract contains 25.36 mg GE/g DWE of total polyphenols and 3.68 mg QuE/g DWE of flavonoids. The condensed tannins are present in small quantity, 0.07 and 0.13 mg Cat/g of DW in ethyl acetate and metanolic extracts of A. imbricatus respectively. P. mauritanica contains also 0.03 and 0.05 mg mg Cat/g of DW of condensed tannins in ethyl acetate and metanolic extracts respectively. The results of the antioxidant activity showed that the ethyl acetate extract had the highest inhibition percentage of free radical DPPH with 48.02% and 69.68% for A. imbricatus and P. mauritanica respectively at the concentration of 1 mg/ml.