Antibiotics are drugs used in human health care and
in veterinary practice to treat bacterial
infections. Since their discovery in the 1930s,
antibiotics have made it possible to cure diseases
such as pneumonia, tuberculosis and meningitis
saving the lives of millions of people around the
world.
Antibiotics attack a metabolic pathway present in
the bacterium (prokaryotes) but not in the host (man
and animals; eukaryotes). Antibiotics of natural
origin can be produced by fungi or soil bacteria.
E.g. penicillin is produced by the fungus
Penicillium notatum. Today, penicillin is made
from cultures of Penicillium chrysogenum that
has been specially adapted for high yields. Natural
antibiotics can be modified chemically resulting in
semi-synthetic products. These products are more
efficient than the natural product, have reduced
side effects, develop less resistance by the
targeted bacteria and / or expand the range of
bacteria that can be treated. An example of complete
synthetic antibiotics are the sulphonamides.
Especially in aqua culture and chicken industry the
use of cheap antibiotics puts high pressure on human
health and bacterial resistance.
Antibiotics are divided into groups depending on
their chemical structures and biological activity.
The main groups are: amphenicols (chloramphenicol),
aminoglycosides, sulphonamides, fluoroquinolones,
macrolides, nitrofurans, tetracyclines and
beta-lactams.