The remarkable and spectacular breakthroughs accomplished by Pasteur, Koch, Jenner, and a
host of others more or less paved the way towards several miraculous discoveries in curing fatal and
dreadful human ailments thereby minimising their immense sufferings. Many meaningful and wonderful
researches also led to the discovery of a good number of causative agents of diseases and altogether
newer techniques for diagnosis, which ultimately rendered the diagnosis of these ailments rather rapid
and precise.
Examples : (a) Widal Test* — for typhoid fever, and
(b) Wasserman Test** — for syphilis.
Importantly, a plethora of dreadful diseases were duly identified and characterized by the presence
of their specific causative microorganisms, such as : Hensen (1874) leprosy (Mycobacterium
leprae) ; Neisser (1879) gonorrhea (Neisseria gonorrhoeae) ; Ogston (1881) wound infections
(Staphylococcus aureus) ; Nicolaier (1885) tetanus (Clostridium titani) ; Kitasato and Yersin (1894)
plague (Yersinia pestis) ; Shiga (1898) dysentry (Shigella dysenteriae) ; Schaudin and Hoffmann (1905)
syphilis (Treponema pallidum) ; Bordet and Gengou (1906) whooping cough (Bordetella pertussis) ;
Ricketts (1909) rocky mountain spotted fever (Rickettsia ricketsii) ;
Some of the important events that mark the history of pharmaceutical microbiology are enumerated
below in a chronological arrangement
Antibiotics : Antibiotic refers to a natural or synthetic substance that destroys microorganisms
or inhibits their growth. Antibiotics are employed extensively to treat infectious, diseases in humans,
animals, and plants. In fact, the terminology ‘antibiotic’ etymologically evidently signifies anything
against life. Obviously, in the event when the microorganisms are critically present in a natural
medium two situations may arise invariably viz., (a) favouring the growth of bacteria usually termed as
‘symbiosis’ ;* and (b) antagonizing the growth of bacteria normally called as ‘antibiosis’.**
Charles Robert Darwin (1809–1882), a British naturalist) aptly commenced scientific and methodical
investigative explorations into the fundamental problems of natural selection and struggle amongst
the interspecies ; and later on came up with his famous doctrine — ‘Survival of the fittest’. Louis
Pasteur (1822–1895) observed for the first time the characteristic antagonistic interrelations prevailing
between the microorganisms of different species.
Joubert and Pasteur first observed the critical destruction of cultures of Bacillus anthracis by
means of certain air-borne microbes. A follow up by Sirotinin (1888) emphatically proved the antagonistic
action of Bacillus anthracis upon the enteric fever, and Blagoveshchensky (1890) carefully ascertained
the antagonistic effect of the blue-pus organism on the Bacillus anthracis. It was ultimately the
miraculous discovery of Lashchenkov (1909) and Alexander Fleming (1922) who meticulously isolated
the enzyme lysozyme***, that was chiefly capable of inhibiting a relatively larger segment of microorganisms.
Chain, Florey, and co-workers (1929) made the epoch making historical development in the
emerging field of antibiotics with the remarkable discovery of wonderful therapeutic and interesting
pharmacological properties of the extracts obtained from the cultures of the mold Penicillium notatum
that eventually gave rise to the formation of the wonder drug ‘penicillin’.
Specifically the antibiotics are extremely useful in the control, management and treatment of a
good number of human infectious diseases but their diversified applications are found to be equally
useful in the meticulous curing and controlling of plant and animal diseases as well. Penicillin has been
effectively employed in the management and control of pests. Antibiotics, in general, are invariably
employed in animal husbandry as ‘feed additive’ to cause enhancement in the fattening of food animals.
Food handling and processing industries extensively make use of antibiotics to critically minimise inevitable
spoilage of fish, vegetables, and poultry products. Present day modern scientific researches
being conducted across the globe do make use of antibiotics as useful and indispensable tools for the
elaborated study of biochemical cellular mechanisms.
Since the discovery of penicillin many more antibiotics came into being as stated under :
Waksman (1944) : Streptomycin — [Streptomyces griseus] — a soil microbe ;
— (1945) : Bacitracin — [Bacillus subtilis] ;
— (1947) : Chloramphenicol (Chloromycetin) — [Streptomyces venezuelae] ;
— (1947) : Polymixin — [Bacillus polymixa] — and various designated polymixins
A, B, C, D, and E.
— (1948) : Chlorotetracycline — [Streptomyces aureofaciens] — a broad-spectrum
antibiotic.
— (1948) : Neomycin — [a species of Streptomyces] — isolated from soil.
— (1950) : Oxytetracycline — [a strain of Streptomyces].
— (1952) : Erythromycin — [Streptomyces erythreus].
It is, however, pertinent to state here that the ‘antibiotics’ may be broadly classified into nine
categories as given below :
[Kar, Ashutosh : Pharmacognosy and Pharmacobiotechnology, New Age International (P)
Ltd., Publishers, New Delhi, 2003].
Important Points : The various important points with respect to the development of antibiotics
are summarized below :
in all approximately 5000 antibiotics have been prepared, characterized, and evaluated for
their therapeutic efficacy till date.
nearly 1000 antibiotics belonging to only six genera of filamentous fungi i.e., including
Cephelosporium and Penicillium have been reported successfully.
about 50 antibiotics have been synthesized from two genera and belonging to the class of
non-filamentous bacteria.
nearly 3000 antibiotics have been prepared from a group of filamentous bacteria i.e., including
streptomyces.
approximately 50 antibiotics are at present actively used in therapeutic treatment and veterinary
medicine around the world.
Importantly, the most common bacteria that invariably attack the humans specifically, and the
diseases they cause or organs of the body they attack, are listed as under :
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