Phytochimie et évaluation des activités antioxydante et anti- inflammatoire d’Helichrysum saxatile Moris.

Abstract

Helichrysum saxatile (Asteraceae) is an aromatic herbaceous plant mainly native to South Africa. It is also distributed in Mediterranean regions, Europe, Western Asia, and Australia. Due to its numerous uses, this plant is cultivated in several regions around the world. It has traditionally been used for the treatment of various diseas-es, particularly respiratory infections, digestive disorders, and inflammations. The aim of this study was to inves-tigate the chemical composition of the 70% hydro-ethanolic maceration extract of the plant aerial part, and evaluate the antioxidant and anti-inflammatory activities. The yield was 13.0% (w/w). Phytochemical screening revealed the presence of several compounds, including polyphenols, flavonoids, quinones, terpenoids and tan-nins, with the absence of saponins, and anthraquinones.The colorimetric determination of total polyphenols, carried out using the Folin–Ciocalteu method, showed a content of 54.81 ± 0.30 μg GAE/mg DE. The determina-tion of flavonoids, flavones and flavanols, performed using the aluminum chloride method, revealed respective contents of 16.13 ± 0.727 μg QE/mg DE and 38.67 ± 0.142 μg QE/mg DE. The determination of condensed tannins using the vanillin method showed a content of 39.66 ± 0.221 μg CE/mg DE. The in vitro antioxidant activity was evaluated using three different methods. The extract exhibited antioxidant activity with an IC50 value of 35.87 ± 0.16 µg/ml in the DPPH assay, as well as inhibition percentages of 184.25% and 225.29% compared to ascorbic acid and quercetin, respectively, in the TAC assay. The FRAP test showed an activity expressed by an EC50 value of 444.3 ± 0.25 μg/ml. Furthermore, the evaluation of the in vitro anti-inflammatory activity revealed an EC50 value of 464.42 µg/ml. The results of this study indicate that Helichry-sum saxatile possesses interesting biological effects that could be valorized in the pharmaceutical and cosmetic industries.