About 1,500 years before the discovery of modern antibiotic tetracycline, North Africans were consuming it with beer, a new study has suggested.

The study based on the chemical analysis of ancient human bones recovered near the Sudanese-Egyptian border found that species of tetracycline-producing bacteria inhabit the soil in the region, which was once known as Nubia.

The practice of brewing beer was widespread in the region, including in ancient Egypt to the north, and the researchers think the Nubians fermented Streptomyces or related species with their grain to brew a thick, sour beer spiked with tetracycline. And everyone from about 2 years old and up consumed it.

The researchers also believe that the Nubians added the bacteria knowing its benefits, though they likely didn’t realise the compounds were antibiotics, LiveScience reported.

“It wasn’t a one-time event, because it was all throughout their bones,” said Mark Nelson, senior director of chemistry at Paratek Pharmaceuticals, Inc.

Nelson, an expert in tetracyclines, carried out the chemical analysis on bones of several individuals, which revealed significant amounts of tetracycline.

The modern world discovered tetracycline in 1948 about 20 years after the first antibiotic, penicillin, was isolated.

The new study, appeared in the American Journal of Physical Anthropology, confirmed the theory of George Armelagos, a professor of anthropology at Emory University, that ancient Nubians may have intentionally used tetracycline.

While studying ancient bones in 1975, Armelagos found that under ultraviolet light, a fluorescent yellow-green band appeared on the bones — an indication of the exposure to the antibiotics.

“My heart stopped,” said Armelagos. “It’s like if you were unwrapping a mummy and you saw Ray-Ban sunglasses.”

Armelagos said attempts to extract the tetracycline from the remains were unsuccessful, until Nelson offered to help out. Nelson, a medicinal chemist, used a colourless, poisonous and highly corrosive acid —— hydrogen fluoride — to dissolve the bones and essentially extract the tetracycline to prove it was the source of the label.

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