Contribution à l’étude phytochimique et l’activité antiradicalaire de la plante Majorana hortensis

Abstract

Molecules endowed with biological activities of natural origin becoming a center of attraction of currentre search by acting against free radicals that can be involved in the development of many diseases by causing damage to different cellular constituents. Majorana hortensis is a plant that be longs to the family Lamiaceae. The objective of this study is the qualitative assay of secondary metabolites in the leaves of this plant on two varieties, one from Egyptian origin and the other from Pakistan. The phytochemical tests carried out made it possible to detect tannins, alkaloids, sterols and saponosides and to show the absence of coumarins and anthocyanins in both varieties and to demonstrate the presence of triterpenes in the Pakistani variety and their absence at the other variety. The two methanolic extracts obtained by maceration gave the following yields 7.08% for EE and 8.34% for EP. The second objective is the quantitative determination of flavonoids and polyphenolswhere the total polyphenol content was determine dusing the Folin-Ciocalteu reagent, itis50,734 ± 3,011μg EAG/mg for the Egyptian extract and 54,76 ± 0.398 μgEAG/mg for the Pakistani extract. Flavonoids were evaluated by the methodusing AlCl3, the flavonoid content isestimated at 36.96 ± 1.7μgEQ/mg and 27.36 ± 0.49 μgEQ/mg for the Egyptian and Pakistani extracts respectively. The other objective of this study is the evaluation of the antioxidant activity of this plant. The antiradical activity was evaluated in vitro by the DPPH radical scavenging test. For both Egyptian and Pakistani varieties, the IC50 values are 9.05 ± 0.416 μg / ml and 5.284 ± 0.149 μg /ml, respectively