Animal sequestration of alkaloids

Animal responses to secondary compounds, including alkaloids, are as diverse as natural chemicals. In the case of alkaloids produced by plants, animal responses depend on evolutionary and co-evolutionary factors. Some animals tolerate alkaloids relatively well, while others have well-developed detoxification systems. 

Animal sequestration of alkaloids is connected not only with taste but also with the toxicity of these compounds. It has been stated that the toxicity of alkaloids is very selective. Aniszewski has published data with some LDjq coefficients for some alkaloids and some pesticides and compared their toxicity from a selectivity point of view. There was clear evidence that alkaloids (sparteine and lupanine) are much more toxic for vertebrates than are some pesticides (e.g. malafione, phenitrothione, etc.). For invertebrates, pesticides were clearly more toxic than alkaloids. Selective toxicity coefficients (STC) were counted by dividing the LDjg for vertebrates by the LDjg for invertebrates. When the STC is 1.0 there is no selectivity when STC is 1 there is invertebrate selectivity and when 1 there is vertebrate selectivity. Selectivity simply means there exists more ability to toxify the organism. 

Generally speaking, alkaloids are more toxic for vertebrates than for invertebrates. The coefficients of the selective toxicity show that alkaloids are very dominantly selective toxins to vertebrates (Table 26). Vertebrate very strong selectivity ( 0.01) is observed in such alkaloids as ajmalicine, brucine, ephedrine, ergometrine, harmaline, lupanine, lupinine, scopolamine and 

The sequestration of alkaloids by insects is considered to be a form of defence. Insects sequester alkaloids and accumulate them for protection against their 

Alkaloids are a part of plant-based sustenance for herbivores, omnivores and according to the latest research, also for 

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