ShK toxin blocks voltage-dependent potassium channel (Kv1.3 channel). ShK toxin can be isolated from the whole body extract of the Caribbean sea anemone (Stichodactylu helianthus). ShK toxin competes with dendrotoxin I and α-dendrotoxin for binding to synaptosomal membranes of rat brain, facilitates acetylcholine release. ShK toxin suppresses K+ currents in cultured rat dorsal root ganglion neurons. ShK toxin also inhibits T lymphocyte proliferation.

Crotonic acid is fatty acid formed by the action of fatty acid synthases from acetyl-CoA and malonyl-CoA precursors. It is involved in the fatty acid biosynthesis. It is also found in water extracts from carrot seeds (Daucus carota L.).

chrysophanol1-(6'-O-malonyl)glucoside