In this study, antioxidant and antihemolytic activities of ethanolic extract of flowers, leaves, and stems of Hyssopus officinalis L. Var. angustifolius were investigated employing different in vitro assay systems. Extracts showed good antioxidant activity. IC50 for 1,1-diphenyl-2- picryl hydrazyl radical-scavenging activity were 148.8 ± 4.31 μg mL−1 for flowers, 79.9 ± 2.63 μg mL−1 for stems, and 208.2 ± 6.45 μg mL−1 for leaves. All extracts showed moderate iron (II) chelating ability. Extracts exhibited good antioxidant activity in the hemoglobininduced linoleic acid model and also they were capable of scavenging hydrogen peroxide in a concentration dependent manner. Extracts showed good antihemolytic activity againts hydrogen peroxide-induced hemolysis (IC50 were 48.51 ± 2.27 μg mL−1 for flowers, 19.47 ± 0.73 μg mL−1 for leaves, and 63.1 ± 2.65 μg mL−1 for stems). The total amount of phenolic compounds in the extracts was determined as gallic acid equivalents and total flavonoid content was calculated as quercetin equivalents from a calibration curve.
