Phytochemical and analytical studies of feed and medicinal plants in relation to the presence of toxic pyrrolizidine alkaloids

Abstract

Pyrrolizidine alkaloids (PAs) are wide-spread in the plant kingdom; they are present in approximately 3 % of all flowering plants. Unsaturated PAs possess hepatotoxic, carcinogenic, genotoxic, teratogenic properties.<br /> Senecio species are common weeds and form part of the primary vegetation in disturbed environments. The distribution and coverage of species such as S. jacobaea and S. aquaticus have remarkably increased in the last decade and these plants pose a latent risk as feed contaminants. The present work analyzed the effect on the PA-degradation of four common feed production methods. <br /> In this work it could be established that if the starting material is contaminated with PA-containing plants, none of the herein analyzed feed production methods produces PA-free products. Hay production as well as pelleting are methods which involve only physical processes and they are the least effective methods for PA reduction. Methods involving chemical and biological processes produced a drastic reduction in the PA-content in the feed material analyzed. The reduction found in these methods might be enough to prevent acute intoxications but do not guarantee the safeness of the product for a long-term consumption.<br /> Regarding the use of PA-containing plants as herbal remedies, the two plants here studied pose a low risk.The PAs found in both plants are pyrrolizidine alkaloids monoester, specifically lycopsamine, imtermedine and their acetylated forms. These kind of PAs are the least toxic ones, and their concentration in the plant is very low, approximately 0.001 %. In addition, the administration route is topical, which reduces the intoxication risk.