Microbiology is the study of microbes or microbiological organism. Microbiology was initially limited to cause and study of infectious disease. Now it is applied widely and practically to study disease and diagnosis and research purpose.
There is a long history and many people contributed in the field of microbiology.
Early history of microbiology.
The Dutch merchant Anthony Leeuwenhoek (1632-1723) has since been called the “Father of Microscopy”.
But earlier, simple “microscopes” which were really only magnifying glasses had one power, usually about 6X – 10X .Sometime about the year 1590, two Dutch spectacle makers, Zaccharias Janssen and his father Hans started experimenting with these lenses.Robert Hooke, an Englishman (who is sometimes called the “English Father of Microscopy” improved their design and capabilities
Leeuwenhoek made careful observations of microscopic organisms, which he called animalcules. Until his death in 1723, van Leeuwenhoek revealed the microscopic world and is one of the first to provide accurate descriptions of protozoa, fungi, and bacteria.
After Leeuwenhoek died, the study of microbiology lost its pace of development.Scientists debated the theory of spontaneous generation, which stated that microorganisms arise from lifeless matter such as beef broth.
But Francesco Redi, showed that fly maggots do not arise from decaying meat, as others believed.
LazzaroSpallanzani also disputed the theory by showing that boiled broth would not give rise to microscopic forms of life.
Louis Pasteur and the germ theory.
Louis Pasteur worked in the middle and late 1800s. He performed numerous experiments to discover why wine and dairy products became sour, and he found that bacteria was the cause.
Pasteur had to disprove spontaneous generation to sustain his theory, and he therefore devised a series of swan‐necked flasks filled with broth. He left the flasks of broth open to the air, but the flasks had a curve in the neck so that microorganisms would fall into the neck, not the broth. The flasks did not become contaminated.
His work also encouraged the belief that microorganisms were in the air and could cause disease. Pasteur postulated the germ theory of disease, which states that microorganisms are the causes of infectious disease. But Pasteur’s attempts to prove the germ theory were unsuccessful.
However, the German scientist Robert Koch worked with anthrax bacteria. He injected pure cultures of the bacilli into mice and showed that the bacilli invariably caused anthrax. The procedures used by Koch came to be known as Koch’s postulates (Figure ). They provided a set of principles whereby other microorganisms could be related to other diseases.
The development of microbiology:
In the late 1800s and for the first decade of the 1900s, scientists further developed the germ theory of disease as enunciated by Pasteur and proved by Koch. There emerged a Golden Age of Microbiology during which many agents of different infectious diseases were identified. Many of the etiologic were discovered during that period, leading to the ability to halt epidemics by interrupting the spread of microorganisms.
But there were no effective drugs against microorganism.After World War II, the antibiotics were introduced to medicine. The incidence of pneumonia, tuberculosis, meningitis, syphilis, and many other diseases declined with the use of antibiotics.
Virus is a very small organism in between life and particulate matter. Work with viruses could not be effectively performed until instruments were developed to see these disease agents.
In the 1940s, the electron microscope was developed and perfected. In that decade, cultivation methods for viruses were also introduced, and the knowledge of viruses developed rapidly.
With the development of vaccines in the 1950s and 1960s, such viral diseases as polio, measles, mumps, and rubella came under control.
Modern microbiology reaches into many fields of human day to day life, including the development of pharmaceutical products, the use of quality‐control methods in food and dairy product production, the control of disease‐causing microorganisms in consumable waters, and the industrial applications of microorganisms.
Microorganisms are used to produce vitamins, amino acids, enzymes, and growth supplements.
They manufacture many foods, including fermented dairy products (sour cream, yogurt, and buttermilk), as well as other fermented foods such as pickles, sauerkraut, breads, and alcoholic beverages.
In this discipline, microorganisms are used as living factories to produce pharmaceuticals that otherwise could not be manufactured. These substances include the
- Human hormone insulin,
- Antiviral substance interferon,
- Numerous blood‐clotting factors and
- Clotdissolving enzymes, and
- A number of vaccines.
Bacteria can be reengineered to increase plant resistance to insects and frost, and biotechnology will represent a major application of microorganisms in the next century.