17 C. Yaman 1 Ş. Önlü H. A. A. Ahmed R. Erenler Journal of Animal and Plant Sciences JAPS 20222022/03/15 32 2 596-603 1018-7081 http://doi.org/10.36899/JAPS.2022.2.0459 <p>The aim of study is to compare the phytochemicals and free radical scavenging activities in methanol extracts of flower, leaf, stem&nbsp;<em>in vitro&nbsp;</em>plantlet, callus of&nbsp;<em>Hypericum perforatum</em>&nbsp;L.&nbsp;<em>In vitro&nbsp;</em>cultures of<em>&nbsp;H. perforatum&nbsp;</em>was established by using MS-B5 medium contained plant growth regulators such as BAP, TDZ and picloram. Total phenolics and flavonoids were analysed by spectrophotometric methods.The stem was the richest in total phenolics (228.9 mg GAE/g extract) and flavonoids (102.4 mg QE/g extract). Quinic acid, gallic acid, (+)-catechin, ferulic acid, vanillic acid,&nbsp;<em>p</em>-coumaric acid, caffeic acid, and quercetin were determinated by LC-MS/MS. Free radical scavenging activities (ABTS and DPPH) of all samples were detected as IC₅₀&nbsp;values, and was compared to standards such as trolox and ascorbic acid. As a result, the stem exhibited the stronger antioxidant activities than other samples, and vanillic acid, ferulic acid and gallic acid could be produced by&nbsp;<em>in vitro</em> culture.</p> Hypericum perforatum, antioxidant activity, in vitro plantlets, phytochemicals Pakistan Agricultural Scientists Forum https://thejaps.org.pk/AbstractView.aspx?mid=Biot-20-0026