The Chemical Profile of Pyrrolizidine Alkaloids from Selected Greek Endemic Boraginaceae Plants Determined by Gas Chromatography/Mass Spectrometry

Abstract

Four Greek endemic Boraginaceae plants, Onosma erecta Sibth. & Sm., Onosma kaheirei Teppner, Onosma leptantha Heldr., and Cynoglossum columnae L. (aerial parts), were screened for their content of pyrrolizidine alkaloids (PAs). TLC with the Mattocks-Molyneux visualization reagent was used as a preliminary qualitative test for PA or PA N-oxide detection. The extracts of the species found to contain PAs and their N-oxides were further analyzed by GC/MS, so as to identify their structures by means of the mass spectra and retention index values of known PAs already published in the literature. Twenty-three PAs were identified. For additional peaks, recognized as possible PAs by their MS pattern, no exact structures were tentatively suggested, as a result of lack of matching literature data. Furthermore, a quantitative PA profile of the species was obtained.

Onosma mutabilis: Phytochemical composition, antioxidant, cytotoxicity, and acute oral toxicity

“…A previous antiradical study correlated deoxyshikonin, pyrrolidine, and pyrrolizidine alkaloids detected from Anabasis articulate to the plant's antioxidant potential (Belyagoubi‐Benhammou et al., 2019 ). The presence of pyrrolizidine alkaloids and their biological roles including antioxidant activity has been reported in various Onosma species including O. arenaria , O. columnae , O. eptantha , O. erecta , O. kaheirei (El‐Shazly et al., 2003 ; Yıldız et al., 2020 ; Damianakos et al., 2014a ). The earlier in vivo investigation showed significant antioxidant activity of Onosma armeniacum K .…”

“…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 ).…”

“…However, some studies have been done on the antioxidant activity of some phytochemicals that were thought to have this property. A previous antiradical study correlated deoxyshikonin, pyrrolidine, and -Shazly et al, 2003;Yıldız et al, 2020;Damianakos et al, 2014a).…”

“…The presence of pyrrolizidine alkaloids and their biological roles including antioxidant activity has been reported in various Onosma species including O. arenaria, O. columnae, O. eptantha, O. erecta, O. kaheirei (El-Shazly et al, 2003;Yıldız et al, 2020;Damianakos et al, 2014a).…”