Boraginaceae, pyrrolizidine alkaloids

Huizing, H.J., and T.M. Malingre. 1981. A chemotaxonomical study of some Boraginaceae Pyrrolizidine alkaloids and phenolic compounds. Plant Syst. Evol. 137(1) 127-134. 

Pyrrolizidine alkaloids have a wide distribution, but are characteristic of certain genera of the Boraginaceae (e.g. Heliotropium, Cynoglossum, and Symphytum), the Compositae/Asteraceae (e.g. Senecio) and the Leguminosae/Fabaceae (e.g. Crotalaria). The pyrrolizidine bases rarely occur in the free form, but are generally found as esters with rare mono- or di-basic acids, the necic acids. Thus, senecionine (Figure 6.18) from Senecio species is a diester of retronecine with senecic acid. Inspection of the ten-carbon skeleton... 

PAs are found widely in the families Asteraceae, Boraginaceae, Fabaceae, and Apocynaceae. About 360 diverse structures have been characterized,23 and these widespread alkaloids are produced by at least 3% of all flowering plants. It is remarkable that one group of animals-the insects-have broken through the formidable alkaloidal defenses represented by the highly toxic pyrrolizidine alkaloids. This evolutionary adaptation has provided a large resource for these insects that is not available to PA-intolerant species, which constitute most of the herbivores. 

No new alkaloids have been discovered within this family. A phytochemical investigation of plants of the Boraginaceae indigenous to France has been carried out.11 Pyrrolizidine alkaloids were detected in 23 species from 14 genera, and N-oxides were present in 12 species. No definite identifications were made. 

Like other members of the Boraginaceae family, the Borage plant also contains pyrrolizidine alkaloids. Seven pyrrolizidine alkaloids have been identified so far in... 

Echium seeds, hke other members of family boraginaceae, contain pyrrolizidine alkaloids. The seeds contain echimidine as a major alkaloid and many minor alkaloids, including retronecine, lycopsamine, 7-acetyUycopsamine, and their derivatives. 

There are no drugs based on the pyrrolizidine alkaloids of the Asteraceae (e.g., Senecio and Symphytum) and Boraginaceae (Crotolaria). However, these alkaloids pose a great threat to human and animal health because of their potential for inadvertent consumption. In the case of 1,2-dehydro derivatives, such as senecio-nine, ingestion leads to non-reversible hepatotoxicity. Pyrrolizidine nucleus formation from two units of ornithine is shown (Fig. 24). 

Pedersen has examined the pyrrolizidine alkaloid content of 19 Danish species of the Boraginaceae. The isolated alkaloids from ten of these species were purified by preparative thin-layer chromatography and investigated by mass spectrometry. The... 

Although other members of the Boraginaceae family contain hepatocarcinogenic pyrrolizidine alkaloids, there are no reports of similar compounds in common borage (Anonymous, 1992). 

Heliosupine, 2-Methyl-2-buienoic acid 7-[[2,3-di-hydroxy-2-( 1-hyd roxyeihyl )-3-meihyl-l -oxob u ioxy]m eihyl]-2,3,5,7a-tetrahydro-tH-pyrroliz.in-i.yl ester cynoglosso-phine. CjjHjuNO, mol wt 397,46, C 60,44%, H 7.86%, N 3.52%, O 28,18%. Hepatotoxic pyrrolizidine alkaloid isolated from Heliotropium supimtm L., Boraginaceae Deni-... 

Pyrrolizidine alkaloids from Compositae and Boraginaceae species... 

There are numerous plants containing pyrrolizidine alkaloids (PAs) and they mainly belong to the Boraginaceae, Compositae and Leguminosae families [31,47, 48],... 

Two further Heliotropium species have been investigated. The dried leaves of H. arguzioides contain 1.2—2.05% alkaloids, the majority of which is heliotrine (44) 16 same alkaloid occurs with incanine in H. olgae The aerial parts of Paracynoglossum imeretinum (Kusnez.) Popov (fam, Boraginaceae) also contain pyrrolizidine alkaloids so far heliosupine, echinatine (45), and their N-oxides have been identified. ... 

Although the presence of pyrrolizidine alkaloids is common in the Boraginaceae family, and the presence of those compounds in lungwort has been suspected, analyses of plants containing pyrrolizidine alkaloids failed to detect... 

Huizing, H.J., T.W.J. Gadella, and E. BQiphuis. 1982. Chemotaxonomical investigations of the Symphytum officinale jxjlyploid complex and S. asperum (Boraginaceae) The pyrrolizidine alkaloids. Plant Sys. Evol. 140(4) 279-292. 

Damianakos H, Sotiroudis G, Chinou I. The chemical profile of pyrrolizidine alkaloids of selected endemic Greek boraginaceae plants of Onosma genus. Planta Med 2012 78(11) 1224. 

Pyrrolizidine alkaloids are the leading plant toxins that have deleterious effects on the health of humans and animals. Over 360 different pyrrolizidine alkaloids are found in approximately 3% of the world s flowering plants. These noxious natural products are primarily restricted to the Boraginaceae (many genera), Asteraceae (tribes Senecionae and Eupatoriae), Fabaceae (mainly the genus Crotalaria), and... 

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