Anti-aging activities of extracts from Tunisian medicinal halophytes and their aromatic constituents.

Six medicinal halophytes widely represented in North Africa and commonly used in traditional medicine were screened for pharmacological properties to set out new promising sources of natural ingredients for cosmetic or nutraceutical applications. Thus, Citrullus colocynthis, Cleome arabica, Daemia cordata, Haloxylon articulatum, Pituranthos scoparius and Scorzonera undulata were examined for their in vitro antioxidant (DPPH scavenging and superoxide anion-scavenging, ß-carotene bleaching inhibition and iron-reducing tests), antibacterial (microdilution method, against four human pathogenic bacteria) and anti-tyrosinase activities. Besides, their aromatic composition was determined by RP-HPLC. H. articulatum shoot extracts exhibited the strongest antioxidant activity and inhibited efficiently the growth of Salmonella enterica and Escherichia coli. P. scoparius and C. arabica inhibited slightly monophenolase, whereas H. articulatum was the most efficient inhibitor of diphenolase activity. Furthermore, H. articulatum exhibited the highest aromatic content (3.4 % DW), with dopamine as the major compound. These observations suggest that shoot extract of H. articulatum, and to a lesser extent of C. arabica, could be used as antioxidant, antibiotic as well as new natural skin lightening agents. Also, possible implication of aromatic compounds in anti-tyrosinase activity is discussed.

Antioxidant potential of hydro-methanolic extract of Prasium majus L: an in vitro study.

Phytochemicals are extensively found at different levels in many medicinal plants. To investigate the phenolic compound content and in vitro antioxidant activity of hydro-methanolic extract from Prasium majus L. (Lamiaceae). The present investigation comprises, estimation of total polyphenol, flavonoid, tannin, in vitro antioxidant assays such as total antioxidant capacity, DPPH, ABTS, beta-carotene and ferric reducing power. P. majus exhibited 64.25 mg GAE g(-1) extract of polyphenol phenol content and better scavenging activity of DPPH (IC50 = 7.95 microg mL(-1)), ABTS*+ (IC50 = 373.78 microg mL(-1)) and beta-carotene (IC50 = 122.56 microg mL(-1)). Our results clearly demonstrated that hydro-methanolic extract P. majus has antioxidant capacity. Therefore is a valuable source of natural antioxidants.