en گياهان دارویی Medicinal Plants پژوهشی Research <div style="text-align: justify;"><b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">Background</span></span></b><i><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">: Lithospermum erythrorhizon</span></span></i><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times=""> is a medicinally valuable plant with diverse biological activities. <b>Objective</b>: This research focused on optimizing the in-vitro cultivation of <i>L. erythrorhizon</i> and establishing an efficient protocol for extracting shikonin from callus tissue.</span></span> <b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">Methods</span></span></b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">: leaf explants were subjected to various concentrations of Kinetin (Kin), 1-naphthaleneacetic acid (NAA), 2,4-dichlorophenoxyacetic acid (2,4-D), Indole-3-acetic acid (IAA), and 6-Benzylaminopurine (BAP) in the LS culture medium to study callus induction. Different concentrations of LS, M9, and MS media, along with varying amounts of BAP, NAA, Kin, and IAA, were employed to investigate callus regeneration. The rooting was examined in concentrations of Indole-3-butyric acid (IBA). For shikonin production, callus was cultivated in LS, MS, and M9 media containing 0.6 mg.l^-1 Kin and 2 mg.l^-1 NAA. <b>Results</b>: The findings shown that the highest callus induction rate occurred in LS medium with 0.6 mg.l^-1Kin and 2 mg.l^-1NAA (93.3%). full-strength LS medium containing 2 mg.l^-1BAP and 1 mg.l^-1NAA led to the highest shoot regeneration. Using 1 mg.l^-1IBA in the LS medium let to improve rooting percentage (> 70%). The suitable substrate for the acclimatization was vermiculite. The shikonin content analysis in callus indicated that the M9 medium was more effective than MS and LS media in producing shikonin-containing calli. The results demonstrated that the concentration of shikonin in calli grown in M9 medium was increased with the number of day&rsquo;s post-explant cultivation.</span></span> <b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">Conclusion</span></span></b><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">: This research can serve as a model for future investigations into optimizing the cultivation conditions of <i>L. erythrorhizon</i>.</span></span></div> Callus induction, Medicinal plant, Micropropagation, Plant growth regulator, Shikonin 40 52 http://jmp.ir/browse.php?a_code=A-10-6921-1&slc_lang=en&sid=1 Zahra Sargazi Moghaddam zahrasm21@yahoo.com 100319475328460048993 100319475328460048993 No Department of Plant Biotechnology and Breeding, Ferdowsi University of Mashhad, Mashhad, Iran Ahmad Sharifi a-sharifi@jdm.ac.ir 100319475328460048994 100319475328460048994 Yes Department of Horticulture Plant Biotechnology, ACECR, Khorasan Razavi Branch, Mashhad, Iran Azadeh Khadem akh.agri69@gmail.com 100319475328460048995 100319475328460048995 No Department of Horticulture Plant Biotechnology, ACECR, Khorasan Razavi Branch, Mashhad, Iran Mahdiyeh Kharrazi ma_kh230@yahoo.com 100319475328460048996 100319475328460048996 No Department of Horticulture Plant Biotechnology, ACECR, Khorasan Razavi Branch, Mashhad, Iran Nasim Safari safari.nasim@ymail.com 100319475328460048997 100319475328460048997 No Department of Horticultural Science and Landscape, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran