Semi-synthetic Chemical Medicines
6. Example - Steroids
Another example is ethinyl estradiol, which is made by semi-synthetic processing of the naturally occurring hormone estrone (an estrogen hormone) and is commonly used in contraceptive pills.
Cortisol and oestrone were originally isolated from animals (cortisol was extracted from the adrenal glands of pigs and cows, and oestrone was purified from the urine of pregnant horses), but they are now both produced in the laboratory by genetically modified microorganisms, such as yeast.