While natural products are of great benefit to our ability to treat disease, they represent a mix of known and unknown compounds and are not subject to the same level of testing and regulation as pharmaceuticals. That creates a potential risk that might be avoided by isolation and purification of active components. A good case can be made about the accessibility and cost of those natural cures that have undergone rigorous testing, but the potential toxic effects should also be included in the analysis.
Wikipedia page on Taxol:
Fantastic long story of Taxol’s discovery and development (worth reading!):
St. John’s Wort
Red Yeast Rice
Duration : 0:10:41