lupinine

Lupinine is a quinolizidine alkaloid present in the genus Lupinus (colloquially referred to as lupins) of the flowering plant family Fabaceae. The scientific literature contains many reports on the isolation and synthesis of this compound as well as a vast number of studies on its biosynthesis from its natural precursor, lysine. Studies have shown that lupinine hydrochloride is a mildly toxic acetylcholinesterase inhibitor and that lupinine has an inhibitory effect on acetylcholine receptors. The characteristically bitter taste of lupin beans, which come from the seeds of Lupinus plants, is attributable to the quinolizidine alkaloids which they contain, rendering them unsuitable for human and animal consumption unless handled properly. However, because lupin beans have potential nutritional value due to their high protein content, efforts have been made to reduce their alkaloid content through the development of "sweet" varieties of Lupinus.

== Toxicity == Lupinine is a hepatotoxin prevalent in the seeds of leguminous herbs of the genus Lupinus. Lupinine and other quinolizidine alkaloids give a bitter taste to naturally growing lupin flowers. Due to the toxicity of quinolizidine alkaloids, lupin beans are soaked overnight and rinsed to remove some of their alkaloid content. However, when the cooking and rinsing procedure is insufficient, 10 grams of seeds are able to liberate as much as 100 milligrams of lupinine.