Chemical Profile and Screening of Bioactive Metabolites of Rindera graeca (A. DC.) Bois. & Heldr. (Boraginaceae) In Vitro Cultures

Abstract

Rindera graeca is a rare endemic plant where in vitro culture has been used in order to investigate bioactive metabolites. Phytochemical study of the in vitro shoots and hairy roots led to the isolation of seven phenolic derivatives and the unusual furano-naphthoquinone rinderol. R. graeca was also analyzed for its pyrrolizidine alkaloids content by LC-MS, and it was found to contain echinatine together with echinatine and rinderine N-oxides. Rinderol, isolated only from in vitro hairy root culture for the first time in the genus, revealed promising bioactivities. It was evaluated in vitro against a panel of microorganisms, showing very strong activity specifically against Gram-positive bacteria (MIC values 0.98 × 10−2–1.18 µg/mL) as well as very interesting antiproliferative effect against the human non-small-cell bronchopulmonary carcinoma cell line NSCLC-N6-L16 and the epidermoid lung cancer cell line A549. These findings were compared with the chemical profile of the plant from nature, while this study is the first to report on the effects of R. graeca extracts obtained from in vitro culture, providing a valuable contribution to the scientific community towards this sustainable method of production of potential bioactive molecules.

HPLC-PDA-ESI-HRMS-Based Profiling of Secondary Metabolites of Rindera graeca Anatomical and Hairy Roots Treated with Drought and Cold Stress

“…This species is recognized as rare species and placed on the ICUN Red List of Threatened Plants [6]. The chemical profile of aerial parts [7], as well as shoots and roots cultivated in vitro [8][9][10][11] of this species, has been investigated. These studies revealed the presence of phenolic compounds, pyrrolizidine alkaloids, naphthoquinone shikonin-type compounds and among them rinderol, a potent cytotoxic agent [7,11,12].…”

“…The chemical profile of aerial parts [7], as well as shoots and roots cultivated in vitro [8][9][10][11] of this species, has been investigated. These studies revealed the presence of phenolic compounds, pyrrolizidine alkaloids, naphthoquinone shikonin-type compounds and among them rinderol, a potent cytotoxic agent [7,11,12]. Rinderol production was optimized in root cultures of R. graeca and its proapoptotic activity was demonstrated [13].…”

Polyurethane Foam Rafts Supported In Vitro Cultures of Rindera graeca Roots for Enhanced Production of Rinderol, Potent Proapoptotic Naphthoquinone Compound

“…Supplementary materials contain comprehensive overview of representative chromatograms from each root line (Figures S1-S3). occurring naturally in mountain territories of Greece [12]. Biotechnological method developed under conditions of the current study, allows producing rinderol via bioengineering technique applying PUF rafts for root immobilization.…”

“…& Heldr. (Boraginaceae) cultivated in vitro and its structure was elucidated using spectral methods ( 1 H/ 13 C, 1 H-1 H and 1 H- 13 C correlation NMR spectroscopy, ESI-MS) [12]. The structure was also identified as naphthofuranin A in collected in Kunming (China) Onosma paniculata (Bur.…”

“…roots [13]. The current work for the first time describes the biotechnological approach which enables the production of rinderol in in vitro root cultures of R. graeca, an endemic plant The current work for the first time describes the biotechnological approach which enables the production of rinderol in in vitro root cultures of R. graeca, an endemic plant occurring naturally in mountain territories of Greece [12]. Biotechnological method developed under conditions of the current study, allows producing rinderol via bioengineering technique applying PUF rafts for root immobilization.…”