Transcript Antibacterials

What keeps us away from
bacteria!


Antibacterial: Chemicals which prevent the growth and
multiplication of bacteria
Antibiotics: Chemicals produced by micro-organisms
that act against other micro-organisms.



The “magic bullet” introduced by German Scientist
Paul Ehrlich, was a chemical designed to attack
pathogenic cells without destroying the host cell.
This concept was used to treat syphilis
In the 1890’s Scientists discovered that some kinds of
fungi could in fact kill bacteria
 1928, discovered
that a mold on a Petri
dish inhibited bacterial growth, he
incurred that the mold had produced a
compound which he called Penicillin.
 This
discovery was not pursued by
Flemming.
 They
isolated the antibacterial that was
produced by the mold. Chain also
worked out how to concentrate and
isolate the Penicillin alone.
 Using corn-steep liquor Florey and Chain
produced the Penicillin in bulk,
revolutionizing medical world.
Industrialized in America in 1944
antibacterial’s reduced the death tolls.
 Reducing
the death toll during the
second world war Penicillin became
largely advertised
 First
of there are two types of bacteria.
 Gram
 Gram
Positive: Simple cell wall
Negative: Complex cell wall with
many layers difficult to penetrate
 Three
simple steps.
 1. Prevents
the cell wall formation
 2. Water then enters the cell (bacteria
walls)
 3. The bacteria is destroyed
 Different
Penicillin's work under different
environments.
 The
R chain on the Pencillen structure is
what's modified in order to gain different
benefits.
 Two


types of antibiotics
Broad spectrum: effective against a wide range of
bacteria including beneficial bacteria. Blood/Urine test
not required. Can be bought over counter
Narrow spectrum: effective against certain types of
bacteria leaving others unharmed, blood and urine
tests determine which bacteria in order to gain a viable
prescription.




Like most topics in chemistry there are exceptions to
Penicillin.
The more Penicillin is used the less effective it
becomes hence larger doses are needed.
Broad spectrum destroys useful bacteria.
Antibacterial drugs are given to animals to prevent
diseases, those animals are then passed on to us for
human consumption. (causing development of more
resistant bacteria)
 To
reduce chances of bacterial resistance
other drugs and an important regime is
needed.
 Some people are allergic to penicillin
causing skin rash and fever.
 In more serious cases anaphylactic shock
can occur which can be fatal.
 Medical consent forms are required for
penicillin allergic patients.