Louis Pasteur, born in 1822, was a pioneering scientist known as the 'father of microbiology and immunology' for his groundbreaking work in fermentation, germ theory, and vaccination. His discoveries included the pasteurization process, the identification of germs in the air, and the development of vaccines for diseases like rabies and anthrax. Pasteur's experiments and theories fundamentally changed the understanding of disease prevention and microbiology.

1. HISTORY AND
DISCOVERIS OF LOUIS
PASTUER

2. HISTORY
Louis pasteur was born on 27th december 1822, in dole,
france. He was a soldier in napoleon’s army and his job
was a gravedigger. As a child louis loved to paint but the
age of 19, he decided to start a scientific career. He
studied physics and chemistry and in 1846 he recived a
PH.D in CHEMISTRY.
He worked as a professor at the university of
strasbourg,paris.
Louis pasteur is known as the “FATHER OF
MICROBIOLOGY & IMMUNOLOGY”

3. * He gave the term crystallography.
* Described the process of fermentation.
* He showed atmospheric air contains micro-organism in
his experiment. ( swan-necked )
* Gave the term pasteurisation.
* He managed to isolate the microbes
* He gave the germ theory of disease.
* Developed vaccine against rabies.
* He discovered the anthrax disease and pebrin
disease(silk worm disease).
Louis Pasteur’s discoveries

4. First discovery(crystallography)
 Louis Pasteur made the first
discovery in 1848 in the field
of crystallography. Using the
glass and tweezers, pasteur
carried out the observation of
crystals tartrates.
 Tartaric acid or tartrates is an
organic compound, formed
two types of crystals,that
could be separate
microscopically. In this way
louis discover the secert
construction of tartaric acid.

5. PROCESS OF FERMENTATION
 Pasteur became intersted in why the local wines in
france were turning sour. In 1854, pasteur concentrated
on the fermentation process. Other chemist belived that
the fermentation of grape juice was a natural chemical
process. But pasteur denied it.
 He came to conclusion that it was a biological process,
during which yeast was reproduced, pasteur observe
under microscope some of oval yeast cells, and barely
some rods commonly called bacteria.
 He belived that yeast played major role in fermentation
process.

6. Some chemical reactions shows
the process of fermentation
1. ALBUMIN SOLUTION  INCUBATION NO FERMENTATION.
2. 2. Grape juice incubation no fermentation.
3. Grape juice + pure yeast  incubation wine + yeasts.
4. Grape juice + yeast heat no fermentation.
5. Grape juice + yeast + bacteria incubation sour wine
6. Grape juice+ yeast+bacteria heat yeast added
incubation good wine.
From this chemical reaction we can see that
yeast and bacteria could bring about
important chemical changes. Yeast appeared
to the vital to fermentation process and the
bacteria made the wine sour.

7. Fermentation process shows that alcohol would
be produced from grape-yeast mixtures. Using
heat will destroyed the yeasts, whereupon
alcohol failed to appear in the grape juice, now
when yeast were returned to the flasks,
fermentation took place, wine was formed, if
we eliminate the bacteria wine would not
become sour.

8. Atmospheric air contains
micro-organism

He showed that atmospheric air contains micro-
organism and that can also be found in
substances such as sugared water, which comes
into contact with the air.
 He heated and boiled water in glass flasks with
curved neck, it turned out that life appears in
the flask in the liquid,until the contact with the
air.

9. Defeat to spontaneous generation
(swan - necked experiment)
 1. Flask containing sterile
broth/liq media - opened to air
 life appears.
 2. Flask containing sterile broth
 neckes sealed  no life
appears.
 3. Flask containing sterile broth
 its side arm opened to air but
heated  no life aapears.
 The flask were left open to
allow entry of any life present in
untreated air. The curvature of
the neck prevented the microbes
from reaching the broth/media.

10. EXPERIMENT OF SWAN-NECKED
FLASK
 Louis Pasteur first
showed that as air
became purer, fewer
microbes could be
located. His swan-
necked flask
provided the final
defeat to the
“spontaneous
generation theory.”

11.  Pasteurisation is the process that kills microbes in
food and drink such as milk, juice, canned food.
 Today pasteurisation is used widely in the dairy
industry.
 Pasteurisation is not intended to kill all micro-
organism in the food,instead it aim to reduce the
number of viable pathogens so they are unlikely to
cause disease.
PASTEURISATION

13. ANTHRAX
 Louis Pasteur discover the immunity in sheep
against anthrax disease.
 Anthrax is an infectious disease that affect
cattle,sheep and other livestock that can be
transmitted to man.
 During that time anthrax was responsible for
killing large population of sheep in france.
 Pasteur supposed that if it were possible to give
an animal a mild attack, this meight be sufficient
to prevent the animal from getting the disease
later on.
GERM THEORY OF DISEASES

14. Pasteur hypothesis was correct. He eventually succeeded
in producing a mild weakend, harmless culture of anthrax,
bacteria. He then took this culture and vaccinated
hundreds of livestocks ,and they were then immune to the
disease.

15. SILK WORM( PEBRINE)
 In middle of the 19th century, a
disease had attacked french
silkworm nurseries.
 Silkworm eggs no longer be
produced in france.
 Pasteur knew virtually nothing
about silkworm, but he soon
became expert silkworm
breeder and identified the
organism that can caused the
silkworm disease.

16. After five years of research, he succeeded in saving
the silk industry through a method that enabled the
preservation of healthy silkworm eggs and
prevented their contamination by the disease
causing orgainsm.

17. Vaccine
( rabies)
 Pasteur is pre-dominatly
well-known for his work
with rabies also known
as hydrophobia.
 Rabies is a highly
infectious disease that
attacks the cental
nervous system.
 Many people have the
misconception that
those who have rabies
act like a wild dog,
barking and howling.

18. Rabies enters the body through the bite of an infected animal
or infected saliva.
On july 6,1885 pasteur tested his new rabies vaccine on man
for the first time.
Joseph Meister was a young man who had been bitten by a
rabid dog. Pasteur gave Meister the rabies vaccine and saved
his life.