8. Cinchona Tree: Malaria Treatment Pioneer
South American indigenous peoples first used cinchona bark to treat fevers. The tree’s compound quinine became the first effective antimalarial. Scientists later developed synthetic versions like chloroquine and hydroxychloroquine with improved stability and reduced toxicity. Parasite resistance has limited their antimalarial use. However, hydroxychloroquine found new applications treating autoimmune conditions such as lupus and rheumatoid arthritis, where it helps reduce inflammation and manage symptoms.