Bioactivities and phenolic composition of Limonium boitardii Maire and L. cercinense Brullo & Erben (Plumbaginaceae): two Tunisian strict endemic plants.

Limonium genus is traditionally used in North Africa for disease treatment and in cosmetic. This study investigates for the first time the antioxidant, anti-inflammatory and enzyme inhibitory activities of two Tunisian endemic plants, L. boitardii and L. cercinense. Analysis of phenolic compounds was carried out by using RP-HPLC. Total phenolic and flavonoid contents, antioxidant activity (antiradical, reducing and total antioxidant activities), tyrosinase and α-glucosidase, collagenase inhibition activities were determined. Inhibiting of NO release in LPS-stimulated macrophages was assessed. L. cercinense exhibited strong antioxidant and anti-inflammatory effects. In the tyrosinase and α-glucosidase inhibitor activity tests, the two species were highly active, especially L. cercinense. High total phenolic and flavonoid contents were recorded in L. cercinense and myricitrin, myricetin, myricetin 3-O-β-D-galatopyranoside, luteolin 7-O-glucoside and rutin were the main phenolics in both species. The results obtained render L. boitardii and L. cercinense as valuable new natural sources for cosmetic and pharmacological applications.