en فارماکوگنوزی Pharmacognosy پژوهشي Original Research <strong>Background</strong>: Flavonoid-derived components have been studied for their therapeutic properties.&nbsp;<br> Objectives: Apigenin has shown remarkable antioxidant and anti-inflammatory features, so we should have a reliable source of apigenin.<br> <strong>Methods</strong>: In this study, we used high-performance liquid chromatography method to compare the amount of apigenin in flower, root, leaf, and stem of three varieties of osmos bipinnatus, i.e., &lsquo;Dazzler,&rsquo; &lsquo;Xanthos,&rsquo; &lsquo;Sensation Pinkie&rsquo;, and in transgenic root culture of C. bipinnatus &lsquo;Dazzler&rsquo;. Besides, the antioxidant activity of C. bipinnatus &lsquo;Dazzler&rsquo; transgenic root culture was evaluated using Ferric Reducing Antioxidant Power (FRAP) assay.&nbsp;<br> <strong>Results</strong>: Dazzler variety flowers showed the highest recovery of apigenin with 0.799 mg/100 mg Dry Weight (DW). However, the Sensation pinkie variety leafs had the lowest recovery with 0.089 mg/100mg. Apigenin content in transformed roots (0.797 mg/100 mg DW) of C. bipinnatus &lsquo;Dazzler&rsquo; was significantly higher than non-transformed roots (0.42 mg/100 mg DW). The ethanolic extract of hairy root showed the FRAP value of 668.1 &micro;M Fe2+/mg that was comparatively more than the wild root FRAP value (426.2 &micro;M Fe2+/mg).<br> <strong>Conclusion</strong>: In conclusion, the presence of apigenin in high amounts in hairy root cultures of C. bipinnatus &lsquo;Dazzler&rsquo; indicates its great potential for the future pharmaceutical industry. Apigenin, Antioxidant, Cosmos bipinnatus, Ferric Reducing Antioxidant Power (FRAP) 87 96 http://pbr.mazums.ac.ir/browse.php?a_code=A-10-72-3&slc_lang=en&sid=1 Soroush Bijani soroush.bijani@gmail.com 10031947532846006616 10031947532846006616 No Zanjan Pharmaceutical Biotechnology Research Center, Zanjan University of Medical Sciences, Zanjan, Iran. Zahra Gharari zahraghrr112@gmail.com 10031947532846006617 10031947532846006617 No Department of Plant Production and Genetics, Faculty of Agriculture, University of Zanjan, Zanjan, Iran. Alireza Ahmadnia alireza.ah91@gmail.com 10031947532846006618 10031947532846006618 No Zanjan Pharmaceutical Biotechnology Research Center, Zanjan University of Medical Sciences, Zanjan, Iran. Hossein Danafar danafar@zums.ac.ir 10031947532846006619 10031947532846006619 No Department of Pharmaceutical Biotechnology, School of Pharmacy, Zanjan University of Medical Sciences, Zanjan, Iran. Ali Sharafi alisharafi@zums.ac.ir 10031947532846006620 10031947532846006620 Yes Zanjan Pharmaceutical Biotechnology Research Center, Zanjan University of Medical Sciences, Zanjan, Iran.