Naphthoquinone rich Onosma visianii Clem (Boraginaceae) root extracts induce apoptosis and cell cycle arrest in HCT-116 and MDA-MB-231 cancer cell lines.

In the present study, five root extracts of Onosma visianii Clem were investigated for their in vitro cytotoxic activity. On the basis of HPLC-PDA analysis, these extracts have proved to be a rich source of naphthoquinones as natural colourants for food and cosmetic industry. All investigated root extracts contain acetylshikonin, isobutyrylshikonin and α-methylbutyrylshikonin as major compounds.

Antibacterial and cytotoxic activities of naphthoquinone pigments from Onosma visianii Clem.

In this study, the antibacterial and cytotoxic activities of isolated compounds from the roots of were investigated. By using different chromatographic techniques and appropriate spectroscopic methods, the seven naphthoquinones were described: deoxyshikonin ( ), isobutyrylshikonin ( ), α-methylbutyrylshikonin ( ), acetylshikonin ( ), β-hydroxyisovalerylshikonin ( ), 5,8--dimethyl isobutyrylshikonin ( ) and 5,8--dimethyl deoxyshikonin ( ). Among the tested compounds, and exhibited the highest antibacterial activities toward all tested bacterial species (MIC and MIC for gram positive bacteria: 6.