Background: Plants produce a vast variety of specialized metabolites which can be a rich
source for lead compounds for the development of new drugs. Alkaloids are one the largest groups of
plant specialized metabolites important for natural product based pharmaceuticals. Of these, lysine
(Lys)-derived alkaloids exhibit a wide range of pharmacological properties which are beneficial for
humans. For instance they have anticancer, anti-Alzheimer’s disease, anti-inflammatory, hypocholesterolemic
and antiarrhtymic effects. Lys-derived alkaloids are widely distributed throughout the plant
kingdom: they can be found in various species from clubmosses to flowering plants. Lys is one of the
most essential amino acids for humans and livestock and is synthesized in the plastids of land plants.
Lys-derived alkaloids can be divided into four major groups including quinolizidine, lycopodium,
piperidine, and indolizidine alkaloids. Despite the importance of these compounds, the biosynthetic
pathways of Lys-derived alkaloids are not well understood. With the exception of indolizidine alkaloids,
Lys decarboxylase (LDC) is the enzyme involved in the first committed step of the biosynthesis
by catalyzing the transformation of L-Lys into cadaverine. Cadaverine is then oxidized by copper
amine oxidase (CuAO) and spontaneously cyclized to Δ1-piperideine Schiff base which is a universal
intermediate for the production of various Lys-derived alkaloids.
Conclusion: In this review, we briefly summarize the recent understanding about the structures, occurrences,
analytical procedures, biosyntheses, and potential health effects and medical applications of
Lys-derived alkaloids with emphasis on quinolizidine alkaloids (QAs).