In 1980, a scientist looking at bone fragments under an ultraviolet microscope noticed the bones were glowing green—a hallmark of the antibiotic tetracycline. The drug latches onto calcium and gets deposited in bone. Nothing unusual. Except these bones were from a Nubian mummy buried 1,600 years ago in Sudan—long before scientists discovered tetracycline, in 1948.
At the time, other scientists said the antibiotic probably just contaminated the bones after death. Because tetracycline’s secreted by a soil bacterium, Streptomyces. To get to the bottom of this, a chemist recently took bone from the mummy of a Nubian child and dissolved it in hydrogen fluoride, a nasty acid that helps extract tetracycline. And this bone extract also matched the chemical signature of tetracycline—evidence that the antibiotic was built into the kid's bones as he grew. That analysis appears in the American Journal of Physical Anthropology.
Anthropologists know the Nubians were skilled brewers. Researchers now believe that the ancient brewmasters learned to purposely make their beer medicinal, by lacing it with grain contaminated with antibiotic-producing Streptomyces bacteria. Just imagine that prescription.
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