Cynoglossum columnae Ten. (Boraginaceae) is an annual species of Mediterranean region. Plants of this family
are investigated for naphthoquinone red pigments, found in the underground parts,
which are bioactive constituents known as: wound healing, anti-inflammatory, antimicrobial,
antitumor agents [1]. Boraginaceae family is also known for its content of hepatotoxic
pyrrolizidine alkaloids (PAs) [2]. Three groups of in vitro root cultures were obtained and investigated: the natural roots cut off from seedlings,
natural roots regenerated from shoots in the following passages and hairy roots obtained
as a result of transformation with Agrobacterium rhizogenes– ATCC 15834 strain. The roots were cultured in various liquid media (ex.: MS, B5,
LS, DCR) and tested for their growth and production of naphthoquinones. The best results
gave DCR medium [3] with twice reduced amount of all components and full sugar value.
Preliminary phytochemical analysis was performed using RP-HPLC DAD method and showed
the presence of six naphtoquinone derivatives in natural roots and their post culture
media (DCR/2); none in the transformed root cultures was observed. Phytochemical investigation
in plants cultivated in nature was made and six PAs have been isolated and determined
by modern spectroscopic methods as rinderine, 3′-acetylrinderine and echinatine in
the form of both their N-oxides as well as their bases after reduction. Sixteen more,
known PAs, were also identified after reduction as echimumiline, heliosupine, heliotridine,
echinatine, rinderine, retronecine, integerrimine and triangularicine type derivatives.
References: 1. Papageorgiou V. P. et al. (1999) Angew. Chem. Int. Ed. 38 (3): 270–300.
2. Chojkier M. (2003)J Hepatol 39: 437–446.
3. Gupta P. K., Durzan D. J. (1985) Plant Cell Rep. 4:177–179.
