Veratrum Alkaloids

The veratrum alkaloids are a group of particularly toxic steroidal alkaloids. A study of the specialist sawfly Rhadinoceraea nodicornis has demonstrated how they store in their haemolymph ceveratrum alkaloids from the host plant, false, or white hellebore Veratrum album. The alkaloids in sawflies can either be directly sequestered, partly metabolized and sequestered, excreted intact or destroyed. The principal alkaloid stored in the haemolymph is 3-acetylzygadenine (Figure 10.3). 3-Angeloylzygadenine of the plant is probably hydrolyzed in the gut to zygadenine and then acetylated. At the same time protoveratrines A and B (Figure 10.3) are degraded. Another sawfly, Aglaostigma sp., fed on false hellebore leaves neither had alkaloids in their haemolymph nor excreted any (Schaffner, Boeve, Gfeller and Schlunegger, Journal of Chemical Ecology, 1994, 20, 3233-3250).

Figure 10.3 Alkaloids from Veratrum plants. The angeloyl ester of zygadenine is present in the plant, the acetyl ester in the insect. Protoveratrines are, at the same time, metabolized completely by the sawfly R. nodicornis

Figure 10.3 Alkaloids from Veratrum plants. The angeloyl ester of zygadenine is present in the plant, the acetyl ester in the insect. Protoveratrines are, at the same time, metabolized completely by the sawfly R. nodicornis zygadenine esters protoveratrine B

zygadenine esters protoveratrine B

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