Introduction to Microbiology & History of Microbiology

1. Introduction to Microbiology
Prof. Dr. Kirankumar Hullatti
M. Pharm., Ph.D., DPPM
Department of Pharmacognosy

2. Content
Introduction
Types of Microorganisms
History of microbiology
Role of microbiology in various fields
Renowned microbiologists and their work
Scope and application of microbiology

3. Introduction
Increase in life expectancy has been recorded for the
majority of the countries over the last 60 years (WHO)
• 45 years in 1950 to 72 years in 2017
Better nutrition and sanitation,
Improved health care and the greater availability of
effective medicines with which to treat common
diseases

4. Introduction
Several infectious diseases
have been eradicated
completely
Worldwide sales of medicines and
medical devices are estimated to have
exceeded $US 1.2 trillion in 2019 and
to reach more than 1.5 by 2024
https://www.statista.com/statistics/280572/medicine-spending-worldwide/

5. Introduction
Microorganisms can, in addition to initiating
infections, cause product spoilage (उत्पादन खराब
होणे) by chemically decomposing the active
ingredient or the excipients.
Pharmacist must know where microorganisms
arise in the environment, the sources of microbial
contamination (दू षित होणे), and the factors that
predispose to, or prevent, product spoilage.

6. Introduction
Commercial antibiotic production began with the manufacture of Penicillin in the
year 1940
Development of recombinant DNA technology in the last three decades
Understanding of the physiology and genetics of microorganisms will also become
more important

7. Introduction
Several of the traditional
diseases that were major causes
of death before the antibiotic
era, e.g. tuberculosis and
diphtheria, are now re-emerging
in resistant form
Adding to the problems posed by
infections in which antibiotic
resistance has long been a problem,
and those like Creutzfeldt–Jakob
disease, West Nile virus , severe
acute respiratory syndrome (SARS)
and Now Covid-19

8. Microorganisms
Major groups
Bacteria
Fungi
Protozoa
Viruses
Less well known
categories like
Chlamydia
Rickettsia
Mycoplasma
Differ enormously in terms of their shape, size and appearance and in their genetic and
metabolic characteristics

9. Microorganism
• Microorganisms and Pathogenic microorganisms
• The microorganisms are tiny, simple-structure but diverse
organisms.
Non-cellular microorganism Prokaryotes Eukaryotes

10. Microorganism
Most of the microorganisms are vital to humans, animals and
plants.
Only a small number of microorganisms, known as pathogenic
microorganisms, can cause human, animal and plant diseases.
Pathogenic microorganisms invade the host, interact with the
host’s defense systems and result in pathology, a process called
infection.

11. Viruses
Viruses do not have a cellular
structure.
They are particles composed of
nucleic acid surrounded by protein;
some possess a lipid envelope and
associated glycoproteins.

12. Viroids
Viroids (virusoids) are even simpler than viruses, being
infectious particles comprising single-stranded RNA
without any associated protein

13. Prions
Prions are unique as infectious agents in that they
contain no nucleic acid.
A prion is an atypical form of a mammalian protein that
can interact with a normal protein molecule and cause
it to undergo a conformational change so that it, in turn,
becomes a prion and ceases its normal function

14. Prions
Mad cow brain

15. Bacteria
Bacteria are single celled prokaryotic microorganisms.
They come in various shape and sizes. They can live in various
conditions and have a complex relationship with humans. They
are among the first life forms to appear on Earth.

16. Fungi
Fungi are eukaryotes and therefore differ from bacteria are
structurally more complex and varied in appearance
The term fungus covers both yeasts and moulds

17. Protozoa
Protozoa are eukaryotic, predominantly unicellular
microorganisms that are regarded as animals rather than plants
Some are parasites of plants and animals, including humans

18. Brief history of the science of microbiology
• Concept of spontaneous generation
• Experiments that were performed to disprove
this erroneous idea.
(उत्स्फ
ू तत षिढी)

19. Concept of spontaneous generation
Spontaneous generation or anomalous generation is an obsolete body of
thought on the ordinary formation of living organisms without descent from
similar organisms
Fleas could arise
from inanimate
matter such as dust
Maggots could arise
from dead flesh
Flies from bovine
manure and
Fish from the mud
of previously dry
lakes

20. Several experiments have been conducted to
disprove spontaneous generation

21. Redi's Experiment (1668)
In 1668, Francesco Redi, an Italian scientist, designed a
scientific experiment to test the spontaneous creation of
maggots by placing fresh meat in each of two different jars.
One jar was left open; the other was covered with a cloth.

22. Redi's Experiment
Days later, the open jar contained maggots, whereas the covered jar contained no
maggots.
He did note that maggots were found on the exterior surface of the cloth that covered
the jar.
Redi successfully demonstrated that the maggots came from fly eggs and thereby
helped to disprove spontaneous generation.

23. John Needham challenge (1748)
In England, John Needham challenged Redi's findings by conducting an experiment in which he
placed a broth, or “gravy,” into a bottle, heated the bottle to kill anything inside, then sealed it.
Days later, he reported the presence of life in the broth and announced that life had been created
from nonlife.
In actuality, he did not
heat it long enough to
kill all the microbes.

24. Spallanzani's Experiment (1768)
Lazzaro Spallanzani, also an Italian
scientist, reviewed both Redi's and
Needham's data
He constructed his own experiment by
placing broth in each of two separate
bottles, boiling the broth in both
bottles, then sealing one bottle and
leaving the other open.

25. Spallanzani's Experiment (1768)
Days later, the unsealed bottle
was teeming with small living
things that he could observe
more clearly with the newly
invented microscope.
The sealed bottle showed no signs
of life.
Except it was noted by scientists of the
day that Spallanzani had deprived the
closed bottle of air, and it was thought
that air was necessary for spontaneous
generation

26. Pasteur's Experiment (1860)
• Louis Pasteur, the notable French
scientist, accepted the challenge
to re-create the experiment and
leave the system open to air.
• He subsequently designed several
bottles with S-curved necks that
were oriented downward so
gravity would prevent access by
airborne foreign materials.
Swan neck duct flask

27. Pasteur's Experiment
• He placed a nutrient-enriched broth in one of the goose-
neck bottles, boiled the broth inside the bottle, and
observed no life in the jar for one year.
• He then broke off the top of the bottle, exposing it more
directly to the air, and noted life-forms in the broth within
days.

28. Pasteur's Experiment
• He noted that as long as dust and other airborne
particles were trapped in the S-shaped neck of
the bottle, no life was created until this obstacle
was removed.
• Pasteur won the Alhumbert Prize in 1862 for this
work

29. “Never will the doctrine of spontaneous
generation recover from the mortal blow of
this simple experiment.
There is no known circumstance in which it
can be confirmed that microscopic beings
came into the world without germs, without
parents similar to themselves”

30. There are many references pertaining to
bacteria in ancient literature such as
Rigveda, Atherveda, Satapadha -
Brahmana, Taittireeya Upanidshad,
Aranyaka, Chandyogyopanishad &
Vishnupurana.
The method of vaccination for prevention
of masurika (small pox) was also described
in Sakteya grandha of Dhanvantri

31. The Role of Microorganisms in Disease
• Agostino Bassi (1773-1856) showed that a
silkworm disease was caused by a fungus
• M. J. Berkeley (ca. 1845) demonstrated
that the Great Potato Blight of Ireland was
caused by a fungus.

32. The Role of Microorganisms in Disease
• Louis Pasteur showed that the péine disease
of silkworms was caused by a protozoan
parasite

33. The Role of Microorganisms in Disease
• Ignaz Semmelweis (1818 - 1865)
Hungarian physician working in Vienna
– He made doctors wash hands in chloride
of lime before touching patients
– Dramatically reduced incidence of
childbed fever
– Met much opposition from medical
establishment, Practice stopped when he
retired and deaths went up.

34. The Role of Microorganisms in Disease
• Joseph Lister (1872-1912) developed a system of surgery
designed to prevent microorganisms from entering
wounds; his patients had fewer postoperative infections,
thereby providing indirect evidence that microorganisms
were the causal agents of human disease; his published
findings (1867) transformed the practice of surgery
Joseph lister carbolic spray

35. The Role of Microorganisms in Disease
• Robert Koch (1843-1910), using criteria
developed by his teacher, Jacob Henle (1809-
1895), established the relationship between
Bacillus anthracis and anthrax; his criteria
became known as Koch's Postulates and are still
used to establish the link between a particular
microorganism and a particular disease:

37. Koch's Postulates
The microorganisms
must be present in
every case of the
disease but absent from
healthy individuals.
The suspected
microorganisms must be
isolated and grown in
pure culture.
The same disease must
result when the isolated
microorganism is
inoculated into a
healthy host.
The same
microorganism must be
isolated again from the
diseased host.

38. The Role of Microorganisms in Disease
• Charles Chamberland (1851-1908) constructed a
bacterial filter that removed bacteria and larger
microbes from specimens; this led to the
discovery of virus as disease-causing agents
Immunological studies
Pasteur–Chamberland filter

39. The Role of Microorganisms in Disease
• Edward Jenner (1798) used a vaccination
procedure to protect individuals from
smallpox
• Louis Pasteur developed other vaccines
including those for chicken cholera, anthrax,
and rabies

40. The Role of Microorganisms in Disease
• Emil von Behring (1854-1917) and Shibasaburo Kitasato (1852-
1931) induced the formation of diphtheria toxin antitoxins in
rabbits; the antitoxins were effectively used to treat humans and
provided evidence for humoral immunity
• Elie Metchnikoff (1845-1916) demonstrated the existence of
phagocytic cells in the blood, thus demonstrating cell-mediated
immunity

41. Industrial Microbiology and Microbial Ecology
• Louis Pasteur demonstrated that alcoholic
fermentations were the result of microbial activity, that
some organisms could decrease alcohol yield and sour
the product, and that some fermentations were
aerobic and some anaerobic; he also developed the
process of pasteurization to preserve wine during
storage

42. Industrial Microbiology and Microbial Ecology
• Sergei Winogradsky (1856-1953) worked with
soil bacteria and discovered that they could
oxidize iron, sulfur, and ammonia to obtain
energy; he also studied anaerobic nitrogen
fixation and cellulose decomposition

43. Industrial Microbiology and Microbial Ecology
• Martinus Beijerinck (1851-1931) isolated
aerobic nitrogen-fixing bacteria, a root-nodule
bacterium capable of fixing nitrogen, and
sulphate reducing bacteria
• Beijerinck and Winogradsky pioneered the
use of enrichment cultures and selective
media

44. Antonie van Leeuwenhoek
• 24 October 1632 – 26 August 1723
• Commonly known as "The Father of Microbiology", and
one of the first microscopists and microbiologists
• Van Leeuwenhoek is best known for his pioneering work
in microscopy
Animalcules

45. Edward Jenner
• 17 May 1749 – 26 January 1823
• Pioneer of smallpox vaccine, the world's
first vaccine
• Jenner is often called "The Father of Immunology"

46. Louis Pasteur
• December 27, 1822 – September 28, 1895
• Pasteur's research also showed that
– the growth of micro-organisms was responsible for
spoiling beverages, such as beer, wine and milk.
– 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.

47. Louis Pasteur
• Disproved the theory of “Spontaneous generation”
• Pasteur used a weakened culture of the bacteria to inoculate
chickens. The chickens survived, and when he inoculated them with
a virulent strain, they were immune to it
• In the 1870s, he applied this immunization method to anthrax
• Pasteur gave these artificially weakened diseases the generic name
of "vaccines", in honor of Jenner's discovery
• Pasteur produced the first vaccine for rabies by growing the virus in
rabbits, and then weakening it by drying the affected nerve tissue

48. Hans Christian Gram
• September 13, 1853 – November 14,
1938
• In 1884, he developed a method for
distinguishing between two major classes
of bacteria.
• This technique, the Gram stain, continues to
be a standard procedure in
medical microbiology. The stain later played
a major role in classifying bacteria

49. Alexander Fleming
• 6 August 1881 – 11 March 1955
• His best-known discoveries are the enzyme lysozyme
in 1923 and the world's first antibiotic substance
benzyl penicillin (Penicillin G) from the
mould Penicillium notatum in 1928,

50. Scope and Applications
Concerned with the use of microorganisms in the
production of drugs that has special applications in
pharmaceutical field

51. Production of antibiotics
Pharmaceutical microbiology is
concerned with the isolation of
antibiotic producing microorganisms
from natural environments such as soil
and water.
Many antibiotics are isolated from
natural microorganisms by the process
of fermentation.

53. Production of enzyme
• Many microbial cell produce
extracellular and intracellular
enzymes and these enzymes are
important for the success of
pharmaceutical fermentation
process.
• They are associated with the
microorganism ability to attack,
degrade and utilize components of
the medium and to accumulate
fermentation products Cellulase
α-amylase

55. Production of bio surfactants
• Biosurfactants can be defined as the surface-active
biomolecules produced by microorganisms with wide-range of
applications.
• Biosurfactants (BS) are amphiphilic compounds excreted
extracellularly and contain hydrophobic and hydrophilic
moieties that reduce surface tension (ST) and interfacial
tensions between individual molecules at the surface and
interface.

56. Classes of Biosurfactants

57. Production of vaccine
Microorganisms are used for preparation of
different types of vaccines that have great impact on
the community by preventing from deadly disease.
• Measles, Chickenpox, Hepatitis, Tuberculosis, Polio etc.

58. Treatment of industrial waste material
• Most industrial processes produce waste waters, salts,
organic matters, which may be toxic.
• Many microbial species are used for decomposition of
such waste material and organic components.
• eg: actinomycetes, fungi, protozoa etc.

59. Sterile product preparation
• Pharmaceutical microbiology plays a major role in
preparation of sterile production.
• It deals with preparation of sterile room, aseptic
technique, detection of microorganisms by sampling
and sterility testing of different sterile preparation.

60. Testing of pharmaceutical
• Raw materials and finished products:
• Test for the detection of Escherichia
coli, Salmonella spp, Pseudomonas spp,
Staphylococcus aureus in pharmaceutical raw
materials and finished products are described in
the Indian pharmacopoeia (IP), United States
Pharmacopoeia (USP), European Pharmacopoeia
(EP) and British Pharmacopoeia (BP)

62. Next Class…
• Classification of Microbes
• Prokaryotes and Eukaryotes
– Cellular characters of Prokaryotes with example
– Cellular characters of Eukaryotes with example
Thank You