Institute of Animal Nutrition and Functional Plant Compounds, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210, Vienna, Austria.
Chem Biodivers. 2022 Nov;19(11):e202200603. doi: 10.1002/cbdv.202200603. Epub 2022 Oct 6.
In recent years, increased attention has been given to plants containing toxic pyrrolizidine alkaloids (PAs). Jacobaea alpina (syn. Senecio cordatus) is a tall forb growing on mountain pastures and meadows containing such alkaloids and therefore, the plant is considered as a noxious weed in these environments. The repartition of toxic macrocyclic PAs in the plant and their evolution during the vegetation period has been studied in two populations. Eight PAs were found where senciphylline and senecionine accounted in most samples for more than 85 % of total alkaloids. Leaves in April and stems in May started with high PA concentrations (19-22 mg/g dry matter), then alkaloid levels declined. This decrease was more rapid in stems than in leaves. Depending on the population, fully developed inflorescences in June and July PA contents were higher or lower than in the respective leaves. Later, also in the inflorescences PA concentration decreased. Combined with growth data total alkaloid content in the whole plant as mg/plant was highest in midsummer and declined afterwards. Finally, new emerging leaves in September had high PA levels, which declined markedly towards the end of the season in November. In sum, over a large period PA concentration appeared to be high enough to present a health risk for grazing animals.
近年来，人们越来越关注含有有毒吡咯里西啶生物碱 (PAs) 的植物。高山紫菀（又名 Cordate Senecio）是一种高大的野草，生长在高山牧场和草地上，这些地方都含有此类生物碱，因此，在这些环境中，该植物被认为是一种有害杂草。在两个种群中研究了植物中有毒的大环 PAs 的分布及其在植被期的演化。在大多数样本中，发现了八种 PAs，其中 sencephylline 和 senecionine 占总生物碱的 85%以上。4 月的叶子和 5 月的茎干开始时具有高的 PA 浓度（19-22mg/g 干物质），然后生物碱水平下降。茎干中的下降速度比叶子中更快。根据种群的不同，6 月和 7 月完全发育的花序中的 PA 含量高于或低于相应的叶子。后来，花序中的 PA 浓度也下降了。结合生长数据，整株植物中的总生物碱含量在仲夏时最高，随后下降。最后，9 月新长出的叶子中含有高浓度的 PA，到 11 月季节末时，PA 水平明显下降。总之，在很长一段时间内，PA 浓度似乎足以对放牧动物的健康构成威胁。
