Contribution of scientists in developing Microbiology
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Aug 08, 2019
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About This Presentation
CONTRIBUTIONS MADE BY ROBERT KOCH, LOUIS PASTEUR,JOSEPH LISTER, JOHN TYNDALL, ANTONIE VAN LEEUWENHOEK IN THE DEVELOPMENT OF MICROBIOLOGY HAS BEEN DESCRIBED
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Language: en
Added: Aug 08, 2019
Slides: 42 pages
Slide Content
Contribution of Scientists in the
development of Microbiology
Ms Jigisha Pancholi
Head
Dept. of Biochemistry & Microbiology
Indian Institute of Ayurvedic Pharmaceutical Sciences
Gujarat Ayurved University
Robert Koch
Robert Koch
He was a German physician and pioneering microbiologist.
His groundbreaking research on tuberculosis, Koch received
the Nobel Prize in Physiology or Medicine in 1905.
Contributions in Microbiology
Robert Koch is widely known for his work with anthrax,
discovering the causative agent of the fatal disease to be
Bacillus anthracis.
Contributions in Microbiology
In India, Koch was able to determine the causative agent of
cholera, isolating Vibrio cholerae.
At that time, it was widely believed that tuberculosis was an
inherited disease
.
However, Koch was convinced that the
disease was caused by a bacterium and was infectious. In 1882,
he published his findings on tuberculosis, in which he reported
the causative agent of the disease to be the slow-growing
Mycobacterium tuberculosis.
Contributions in Microbiology
He gave experimental support for the concept of infectious
disease.
Koch created and improved laboratory technologies and
techniques in the field of microbiology.
Following his work with anthrax, Koch set out to find a better
way of growing and isolating microorganisms
.
Previously, he had used liquid cultures, which were easily
contaminated with other organisms, and he needed live animals
as incubators to grow the bacteria he was studying.
Contributions in Microbiology
In an attempt to grow bacteria and isolate to get pure cultures,
Koch began to use solid nutrients such as potato slices.
Through these initial experiments, Koch observed individual
colonies of identical, pure cells.
Coming to the conclusion that potato slices were not suitable
media for all organisms, Koch later began to use nutrient
solutions with gelatin.
Contributions in Microbiology
However, he soon realized that gelatin, like potato slices, was
not the optimal medium for bacterial growth, as it did not
remain solid at 37 °C, the ideal temperature for growth of most
human pathogens.
As suggested to him by Walther and Fanny Hesse, Koch began
to utilize agar to grow and isolate pure cultures, as this
polysaccharide remains solid at 37 °C, is not degraded by most
bacteria, and results in a transparent medium.
With the help of his
assistant Julius Richard
Petri, who is remembered
for the invention of the
petri dish, he developed
methods for isolating
colonies of
microorganisms.
Contributions in Microbiology
Koch’s postulates
The organism must always be present, in every case of the
disease.
The organism must be isolated from a host containing the
disease and grown in pure culture.
Samples of the organism taken from pure culture must cause
the same disease when inoculated into a healthy, susceptible
animal in the laboratory.
The organism must be isolated from the inoculated animal and
must be identified as the same original organism first isolated
from the originally diseased host.
Louis Pasteur
Louis Pasteur
Louis Pasteur was a French chemist and microbiologist
renowned for his discoveries of the principles of vaccination,
microbial fermentation and pasteurization.
He is remembered for his remarkable breakthroughs in the
causes and preventions of diseases, and his discoveries have
saved countless lives ever since.
He was the Director of the Pasteur Institute, established in
1887, till his death, and his body lies beneath the institute.
He is known as father of modern Microbiology.
Awards And Honors
The Royal Society of London presented him the Rumford
Medal for his discovery of the nature of racemic acid and its
relations to polarized light in 1856.
The French Academy of Sciences awarded him the Montyon
Prize in 1859 for experimental physiology, the Jecker Prize in
1861, and the Alhumbert Prize in 1862.
He was awarded the Copley medal in 1874 for his work on
fermentation.
In 1883 he became a foreign member of the Royal Netherlands
Academy of Arts and Sciences.
He won the Leeuwenhoek medal, microbiology's highest
Dutch honor in Arts and Sciences, in 1895.
Awards And
Honors
In many localities worldwide, streets are
named in his honor.
Both the Institute Pasteur and
Université Louis Pasteur were named
after Pasteur.
The schools Lycée Pasteur in Neuilly-sur-
Seine, France, and Lycée Louis Pasteur in
Calgary, Canada, are named after him.
In South Africa, the Louis Pasteur Private
Hospital in Pretoria, and Life Louis
Pasteur Private Hospital, Bloemfontein,
are named after him. Louis Pasteur
University Hospital in Košice, Slovakia is
also named after Pasteur.
Awards And Honors
A statue of Pasteur is erected at San Rafael High School
in San Rafael, California
The UNESCO/Institute Pasteur Medal was created on the
centenary of Pasteur's death, and is given every two years
in his name
Contributions in Microbiology
Pasteur demonstrated that fermentation is caused by the growth
of micro-organisms, and the emergent growth of bacteria in
nutrient broths is due not to spontaneous generation, but rather
to biogenesis (Omne vivum ex vivo "all life from life").
Contributions in Microbiology
He did experiments to prove spontaneous generation of
organisms was wrong and supported the germ theory.
Contributions in Microbiology
He performed experiments that showed that without contamination,
microorganisms could not develop.
Pasteur exposed boiled broths to air in swan-neck flasks that contained a
filter to prevent all particles from passing through to the growth medium,
and even in flasks with no filter at all, with air being admitted via a long
tortuous tube that would not allow dust particles to pass.
Nothing grew in the broths unless the flasks were broken open, showing that
the living organisms that grew in such broths came from outside, as spores
on dust, rather than spontaneously generated within the broth.
This was one of the last and most important experiments disproving the
theory of spontaneous generation for which Pasteur won the Alhumbert
Prize in 1862.
Contributions in Microbiology
Pasteur's research also showed that the growth of micro-
organisms was responsible for spoiling beverages, such as beer,
wine and milk.
Contributions in Microbiology
With this established, he invented a process in which liquids
such as milk were heated to a temperature between 60 and
100°C.
This killed most bacteria and moulds already present within
them.
The method became known as pasteurization, and was soon
applied to beer and milk.
Contributions in Microbiology
He reduced mortality from puerperal fever and created the first
vaccines for rabies and anthrax.
Joseph Lister
Joseph Lister
Joseph Lister was a British surgeon and a pioneer of
antiseptic surgery.
Awards and Honors
Lister was President of the Royal Society between 1895 and
1900.
Following his death, a Memorial Fund led to the founding of
the Lister Medal, which is the most prestigious prize that
could be awarded to a surgeon.
Awards and Honors
Two postage stamps were issued in September 1965 to
honour Lister for his contributions to antiseptic surgery.
Lister is one of the two surgeons in the United Kingdom
who have the honour of having a public monument in
London.
Awards and Honors
In 1903, the British Institute of Preventative Medicine was
renamed Lister Institute of Preventive Medicine in honour of
Lister.
Lister Hospital in England is named in honour of Lister.
The Discovery Expedition of 1901–04 named the highest point
in the Royal Society Range, Antarctica, Mount Lister.
Awards and Honors
In 1879, Listerine mouthwash was named after him for his
work in antisepsis.
Microorganisms named in his honour include the pathogenic
bacterial genus Listeria as well as the slime mould genus
Listerella.
He is known as father of modern surgery.
Contributions in Microbiology
Lister successfully introduced carbolic acid (now known
as phenol) to sterilize surgical instruments and to clean
wounds, which led to a reduction in post-operative
infections and made surgery safer for patients.
Until Lister's studies of surgery, most people believed that
chemical damage from exposures to bad air was
responsible for infections in wounds. Hospital wards
were occasionally aired out at midday as a precaution
against the spread of infection via miasma (bad air), but
facilities for washing hands or a patient's wounds were
not available.
Contributions in Microbiology
A surgeon was not required to wash his hands before seeing a patient
because such practices were not considered necessary to avoid infection.
Pasteur suggested three methods to eliminate the micro-organisms
responsible: filtration, exposure to heat, or exposure to
solution/chemical solutions.
Lister confirmed Pasteur's conclusions with his own experiments and
decided to use his findings to develop "antiseptic" techniques for wounds
.
Contributions in Microbiology
Lister tested the results of spraying instruments, the surgical
incisions, and dressings with a solution of carbolic acid. Lister
found that the solution swabbed on wounds remarkably reduced the
incidence of gangrene.
He instructed surgeons under his responsibility to wear clean
gloves and wash their hands before and after operations with 5%
carbolic acid solutions. Instruments were also washed in the same
solution and assistants sprayed the solution in the operating theatre.
One of his additional suggestions was to stop using porous natural
materials in manufacturing the handles of medical instruments.
Contributions in Microbiology
He also developed a method of repairing kneecaps with metal
wire and improved the technique of mastectomy (surgical
removal of breast).
Antoni van leeuwenhoek
Antoni van leeuwenhoek
He was a Dutch tradesman and scientist.
He is commonly known as the Father of Microbiology, and
considered to be the first microbiologist.
He is best known for his work on the improvement of the
microscope and for his contributions towards the establishment
of microbiology.
Contributions in Microbiology
Antonie van Leeuwenhoek
made more than 500 optical
lenses.
He also created at least 25
single-lens microscopes, of
differing types.
These microscopes were made
of silver or copper frames,
holding hand-made lenses.
Those that have survived are
capable of magnification up to
275 times.
Contributions in Microbiology
Using his handcrafted microscopes, he was the first to observe
and describe microorganisms, which he originally referred to as
animalcules (from Latin animalculum = "tiny animal").
Most of the "animalcules" are now referred to as unicellular
organisms, though he observed multicellular organisms in pond
water.
Contributions in Microbiology
Van Leeuwenhoek's main discoveries are:
the infusoria (protists in modern zoological classification), in
1674
the bacteria, (e.g., large Selenomonads from the human mouth),
in 1676.
the vacuole of the cell
the spermatozoa in 1677
the banded pattern of muscular fibers, in 1682
John Tyndall
John Tyndall
John Tyndall (2 August 1820 – 4 December 1893) was a
prominent Irish 19th-century physicist.
John Tyndall proved that dust carries the germs and if no
dust in the air, the sterile broth remained free of microbial
growth for indefinite period. This outcome disapproved
spontaneous generation theory.
He also developed a sterilization method “Tyndallization”,
referred as intermittent or fractional sterilization. The
subsequent cooling and heating by steam for 3 days remove the
germs and their spores.
Tyndallization
Tyndallization essentially consists of heating the substance
to boiling point (or just a little below boiling point) and
holding it there for 15 minutes, three days in succession.
After each heating, the resting period will allow spores
that have survived to germinate into bacterial cells; these
cells will be killed by the next day's heating.
During the resting periods the substance being sterilized
is kept in a moist environment at a warm room
temperature, conducive to germination of the spores.
Tyndallization
When the environment is favourable for bacteria, it is
conducive to the germination of cells from spores, and
spores do not form from cells in this environment.
The Tyndallization process is usually effective in practice.
But it is not considered totally reliable—some spores may
survive and later germinate and multiply.
It is not often used today, but is used for sterilizing some
things that cannot withstand pressurized heating, such as
plant seed.