Question

how is antibiotics are discovered and extracted?

Answer 1

Alexander Fleming was studying an enzime present in the saliva, when he noticed a mildew that qas growing in a culture plate spread a substance which apparently, stopped bacteria growth. Fleming isolated the fungus, this took him to discover penicillin, the first antibiotic, in 1928. First processes to produce penicillin implied growth of penicillium notatum over a liquid surface (Czapek-Dox-glucose).
Period of incubation was 6-12 days and then penicillin was extracted with solvents, when the mycelium was already separated.

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