| MadSci Network: Biochemistry |
While I couldn't find any information directly about Milletia taiwaniana, there is a lot known about the root extract from Derris elliptica. "Derris dust" has been used for centuries as a pesticide, and more specifically as the main ingredient in Sheep Dip. The active ingredient is rotenone, a natural insecticide that occurs in many plants, especially members of the family Leguminoseae, of which Milletia is a member. Rotenone has also been used as a pesticide on crops, and its toxicity is well established (although some recent evidence has possibly linked rotenone exposure to Parkinson's disease). Rotenone (and Derris dust) has been used more recently to control fish populations, and its usefulness in this application is still debatable. (Biochemically, rotenone is an inhibitor of the mitochondrial enzyme NADH-quinone oxidoreductase, which is essential for aerobic metabolism.) I couldn't find any mention of the poisoned fish coming back to life, and I doubt the effects of rotenone are sufficiently reversible for this to be the case - "coming back to life" is usually associated with neurotoxins, like tetraodotoxin and curare, which induce paralysis rather than causing death directly. Possibly, the reference was originally to the fact that rotenone treatment of a large body of water will not completely decimate any given fish population, such that a species that disappeared after the treatment (presumed dead), might reappear after a year when its numbers are noticably higher.
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