Analgesic and antioxidant activities of Algerian Retama raetam (Forssk.) Webb & Berthel extracts

Part of this work deals with the isolation and structure elucidation of the main polar secondary metabolites of the aerial parts of Retama raetam (Forssk.) Webb & Berthel, as well as the evaluation of their potential analgesic properties, while the rest deals with the antioxidant activities of the aqueous extracts of roots, stem, fruits and flowers of the plant. It was found that the isoflavones genistein 1, 6-hydroxygenistein 2, 3'-Omethylorobol 3, pratensein 4, biochanin A 8, the flavones 6-hydroxyapigenin 7 and luteolin 5, the flavonol kaempferol 6, as well as the phenolic compound p-coumaric acid 9 reduce significantly the pain at a concentration dose of 1 mg/kg. The most active compounds were 3 and 8 (86.19% and 75.23%, respectively). The obtained aqueous extracts of R. raetam were also evaluated for their antioxidant activities using two different photometric methods; the results revealed that all extracts exerted very low free radical scavenging activity compared to the well-known butylated hydroxytoluene (BHT) and lower hydrogen peroxide blocking activity than positive control gallic acid.