Bakr R.O.El-Raey M.A.E.A.Farouk C.N.Ahmed H.E.Said O.M.E.Pharmacognosy DepartmentOctober University for Modern Sciences and ArtsGizaEgypt; Phytochemistry and Plant Chemosystematics DepartmentNationalResearch CenterDokkiCairoEgypt2020-01-252020-01-2520129750185https://doi.org/https://t.ly/LX9vXScopusEuphorbia hirtaL. (asthma weed, pill bearing spurge),is one of the most important species of Euphorbiaceaeindigenousto Egypt and widely used in folk medicine. It was the subject for many phytochemical and biological studies but correlation between phytoconstituents and biological activities were not well studied.The aim of the present study wasto correlatethe antioxidant and cytotoxic activities against twoof the most important health problems in Egypt with the main constituents in E hirta (phenolic and flavonoid). The different fractions obtained from successive extraction of E hirta were screened for their radical scavenging ability using 1,1 -diphenyl-2-picryl hydrazine (DPPH) testin addition to cytotoxicity using Sulforhodamine B (SRB) assay against liver (Huh-7) and lung (A-549) cell carcinoma. Phenolic and flavonoid contents were estimated using colorimetric assays (Folin-Ciocalteuand aluminum chloride assays respectively).Ethyl acetate (EtOAc) fractionappeared as potent radical scavenger (IC50 5.4�0.65?g/ml and IC90 11.9�0.84?g/ml) and had the highest potency against Huh-7 (IC50 36.7�1.02 ?g/ml)and A-549 (IC50114.4 �0.78 ?g/ml) cancer cell lines. These results are attributed to the highest flavonoid concentration (23�1.06 mg/gquercetin equivalent)in EtOAcfraction in addition to high content of phenolics (88.9 �0.57mg/g gallic acid equivalent). Further studies are necessary to isolate and identify the ethyl acetate's bioactive compounds and evaluation of their biological activities.EnglishCytotoxicityDPPHEuphorbia hirtaPhenolic contentSRB assay1,1 diphenyl 2 picrylhydrazylacetic acid ethyl esterantineoplastic agentantioxidantascorbic acidbutanolchloroformEuphorbia hirta extractflavonoidphenol derivativeplant extractscavengersulforhodamine Bunclassified drugwaterantineoplastic activityantioxidant activityarticlecell viabilitycolorimetrycontrolled studydrug cytotoxicitydrug effectdrug mechanismdrug potencyEgyptEuphorbia hirtahumanhuman cellIC 50phytochemistryArticlehttps://doi.org/