PHYTOCHEMICAL SCREENING AND ANTIMICROBIAL ACTIVITIES OF SOME WILD MEDICINAL PLANTS OF THE WESTERN MEDITERRANEAN COASTAL REGION, EGYPT

Four wild plant species (Chrysthanthemum cornarium, Capparis spinosa, Carthamus lanatus, Haplophyllum tuberculatum) were investigated for their antioxidant activity, phenolic and flavonoid contents of their methanolic extracts. The antioxidant activity of the extracts was assessed their free radical scavenging properties using DPPH. Total phenolics and total flavonoids were detected by spectrophotometric and HPLC methods. The HPLC analysis compared with 14 reference standard phenolic compounds, results confirmed that gallic acid , chlorogenic acid, caffeic acid, 2,5- dihydroxy benzoic acid, and catechin were detected in the four methanolic plant extracts. HPLC chromatograms of the plant extracts showed that there was noticeable valuation in the distribution of phenolic compounds in the four studied species. Six bacterial strains   were used in this study, three Gram-positive and three Gram-negative. Concerning with antimicrobial activity, results showed that plant extracts of the studied species are a great source of phenolic compounds and represent the highest antibacterial activity against Gram-positive and negative bacteria. Results revealed that  extracts represents the highest antibacterial activity against Gram-positive and negative bacteria and largest inhibition zone for bacterial strains were exhibited by the extracts of Carthmus lanatus (11 mm)  followed by that of Haplophyllum tuberculatum  (8mm). However, Chrysthanthemum cornarium extract showed the least inhibition zone (5mm).