ABSTRACT
This chapter provides state-of-the-art overviews on foodborne diseases caused by Pyrrolizidine alkaloids (PAs) in relation to their etiology, biology, epidemiology, clinical presentation, pathogenesis, diagnosis, treatment, and prevention. PAs are a class of secondary metabolites synthesized by plants as a defense mechanism against invertebrate herbivores such as caterpillars. PAs are made up of two fused five-member carbon rings with a bridging nitrogen at position 4, forming a necine base, which may either be saturated or possess a double bond in the 1,2-position. PAs represent a constitutive plant defense mechanism against invertebrate herbivores and other microorganisms. As clinical and histologic features associated with PA exposure resemble those caused by other toxic and infectious diseases, diagnosis on the basis of clinical signs, compatible changes in biochemical parameters, and history of exposure is only presumptive. PAs are secondary metabolites produced by a large number of flowering plants to deter or defend against insect herbivores.
