Alexander Fleming discovered penicillin in 1928 when he noticed a mold that had inhibited the growth of bacteria. Howard Florey and Ernest Chain further researched penicillin's effects and purified it. They used penicillin to treat a dying policeman in 1941. Later, methods were developed for mass producing penicillin using corn steep liquor and fungal strains, enabling its widespread use.

1. D6: Antibacterials
Caleb Jarrell, Elizabeth Eden, Winnie
Shao

2. Introduction
 Antibacterials are chemicals which
prevent the growth and
multiplication of bacteria

3. D.6.1: historical development of
penicillin
 Name to know: Alexander Fleming

4. D.6.1: historical development of
penicillin
 In 1928, Alexander Fleming left an open
Petri dish containing a culture of
Staphylococcus aureus in the lab while on
holiday.
 Upon return, he noticed a mould that had
grown and inhibited the growth of the
bacterium. He deduced that the mould
(Penicillium notatum) produced a
compound (penicillin) that inhibits the
growth of bacteria.
 He published his results, but never
pursued them further.

5. Historical development cont.
 Names to know: Howard Florey
 Ernest Chain

6. Historical Development cont.
 Florey and Chain used penicillin on a
policeman who was dying of septicaemia
in 1941, and recorded a dramatic
improvement in his condition (before he
died due to lack of a supply of penicillin)
 They discovered penicillin's therapeutic
action and its chemical composition, and
overcame problems associated with
isolating and purifying penicillin

7. Historical development cont.
 Florey went on to research large scale
production of penicillin and efficient
extraction of the active ingredient.
 In America, Jasper Kane and other Pfizer
scientists found that by growing strains of
penicillin mould in large tanks containing
corn-steep liquor they could produce in
bulk.
 In the 1950s the structure of penicillin
was determined, enabling different types
to be synthesized without recourse to
moulds.

8. Historical Development Cont.
 Moyer, Coghill and Raper at
the NRRL developed methods for
industrialized penicillin production
and isolated higher-yielding strains
of the Penicillium fungus.