| خلاصه مقاله | Abstract
Introduction: The genus Marrubium with about 40 species of flowering plants is considered to be one of the largest genera of lamiaceae. Since ancient times, this genus has been accepted for remedy of several disorders such as dyspeptic complaints, loss of appetite, cough, wound healing and as a choleretic in digestive and biliary complaints. Phytochemical analyses of Marrubium have been demonstrated that it is rich in polyphenols, flavonoids, phenylethanoids, sterols, saponins and tannins.
Objectives: According to the widespread usage of the species in traditional and folk medicine in Iran, M. propinquum was selected for phytochemical study along with an assessment on antioxidant activity which has not been studied so far.
Experimental: The air-dried and powdered aerial parts of M. propinquum was successively extracted at room temperature with solvents of increasing polarity, petroleum ether, chloroform and methanol using maceration method. The methanolic extract (2g) was subjected to Sep-Pak fractionation using a step gradiant of MeOH-H2O mixture (10:90, 20:80, 40:60, 60:40, 80:20, 100:0). Furthermore, purification of the fractions by preparative reversed-phase HPLC yielded 24 compounds. The structure of three compounds have been elucidated by 1D NMR and 2D NMR. The essential oil was obtained by hydro-distillation with a Clevenger-type apparatus. The composition of the essential oil was determined by GC-MS. Additionally, free radical scavenging activity of the methanolic extract and its fractions were evaluated using DPPH and nitric oxide assays.
Results: Preparative reversed-phase HPLC analysis of 40% and 60% Sep-Pak fractions yielded a flavonoid, an acylated flavonoid and one phenylethanoid glycosides. Essential oil was typically a complex mixture of mainly non-terpenoids, sesquiterpene hydrocarbons, oxygenated sesquiterpene and some monotrpenes.The methanol extract and its fractions showed significant antioxidant activity.
Conclusion: Phytochemical analysis on the aerial parts of M. propinquum showed the presense of phenolic compounds (flavonoid, acylated flavonoid and phenylethanoid glycosides) with significant antioxidant activity. |