Chemical profile, antioxidant and photoprotective activities of essential oil and crude extracts of Algerian Thymus serpyllum
Résumé
Thymus serpyllum is an aromatic and medicinal plant widely used in Algerian folk medicine. It was collected from Mascara region North West of Algeria and studied in the aim to provide more knowledge about chemical composition, antioxidant and photo-protective activities of essential oil, ethanolic and infusion extracts. The chemical analysis of investigated T. serpyllum EO was performed for the first time in this research work. It was carried out by GC/MS for identifying 25 components where the dominated compounds were Carvacrol (66%) and γ–Terpinene (11.5%). The phenolic profile of ethanolic and aqueous infusion extracts was performed using HPLC chromatography and the data showed the Benzoic acid and Rosmarinc acid were found as major compounds. Extracts showed an excellent source of total phenols and flavonoids. Antioxidant activity was evaluated using DPPH, Galvinoxyl radical (GOR), CUPRAC, reducing power and O-phenanthroline approaches. All extracts showed a significant antioxidant capacity with different mechanisms. However, ethanol and infusion extracts showed stronger capacity than EO. Moreover, the photoprotective activity of T. serpyllum extracts was explored for the first time in our study. Extracts exhibited high values of sun protective factors (SFP) with 38.34±2.29 and 38.82±2.23 for ethanol and infusion extract respectively. Results of our study may encourage the pharmacologic, food and cosmetic sectors to use the wild thyme as natural and healthy source of active compounds.