Brine shrimp (Artemia sp.), small invertebrates that dwell in sea water and other saline ecosystems, are frequently used in laboratory studies to evaluate toxicity values as a measure of median lethal concentration values, or LC50, as they offer a simple, quick and cost-effective way to test plant extracts. Brine shrimp larvae were submerged in 501 total vials of aqueous and ethanolic plant extract solutions, and scientists recorded their rates of mortality after 24 hours.
Testing of the aqueous extracts showed high toxicity values for 55 of the total plant species, with 18 species having median toxicity values and another 18 species having low toxicity. The alcoholic extracts proved exponentially more toxic, with 220 plant species showing high toxicity values, 43 having median toxicity and 23 showing low toxicity.
"Preparation methods by curanderos are taking this into account, and most traditional remedies such as medicinal teas are made with simple water extracts instead of alcoholic ones, thus avoiding potential toxic effects in patients," said Bussmann. "However, traditional knowledge about medicinal plant use is rapidly eroding and many of these plant species are threatened with extinction. Roughly four out of five people in developing countries rely on plants for their primary health care, so studies su
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Missouri Botanical Garden