“…The previous research works declared alkaloids and naphthoquinones as the main phytochemical component of O. erecta Sibth. & Sm., O. kaheirei, O. arenaria pennina Br.‐Bl., O. hetrophyllum, Onosma microcarpum (Damianakos et al., 2014a ; El‐Shazly & Wink, 2014 ; Mellidis, 1988 ; Wiedenfeld & Abbildungen, 1993 ). In addition, a study by Vukic et al showed seven napthoquinon (deoxyshikonin, isobutyrylshikonin, alpha methylbutyrylshikonin, acetylshikonin, alpha‐hydroxyisovalerylshikonin, 5,8‐O‐dimethyl isobutyrylshikonin, and 8‐O‐dimethyl deoxyshikonin) as the main chemical contents of O. Visianii extract (Vukic et al., 2017 ).…”