Development of a microbiology as a discipline
Introduction:
Early developments in microbiology
Ancient history of a microbiology
The Ancient history of a microbiology is to be found in the writings of a priests, philosophers, religious books and writing of a scientist, who made earnest effort to study and understand the basic biological problems. Among ancient peoples, epidemics and even endemic disease were regarded as a supernatural in origin and sent to by “God” as a punishment for the sins of a man.
Since man is a wil-ful and sinful by Nature. During Ancient history of a microbiology there was never any dearth in a finding a particular set of a sins to justify specific epidemic disease . War famine and pestilence known to ride together throughout history.
Infection and contagion:
Egyptians are credited to have a vague notion that disease could be transmitted by personal contact or from the clothes of the patient and even by living in the same house of a former leper. The principle of a contagion by invisible creature (microorganisms) letter recorded by Varro in the first century before B.C. and the concept was familiar to Greeks, Romans and Arabic writers.
Boccaccio and his group certainly believed that plague was contagious disease when they fled from Florence in 1348 to escape its ravages.
Fracastoro of Verona in 1546 published his book on contagious disease and describe the transmission of a disease by direct contact, by inanimate fomites and through the air,”addistans”.He also observed that causative agent in syphilis was contagium vivam leaving germ,seeds of which were passing from one infected person and produced the same disease in another which received them.
The discovery of a microbial world and microscope
Early observations of a microorganism
The Roman philosopher Lucretius (about 98 to 55 B.C.) and the physician Garolomo Fracastoro l(1546) suggested that disease was caused by invisible living creatures( true geometry of a disease) which was not confined till the microscope was invented to visualise them.
In 1590 Hans and Zaccharius Jansen combined two double convex lenses in a tube and constructed the first compound microscope in Holland. In 1610 G.Gallilio developed a simple microscope with better facilities. Various scientist tried to study cells of animals, plant tissues and living small creatures by using this two types of a microscope.
Kircher (1658), a German mathematician, observed innumerable minute worms in the blood of a plague patient. This was the first attend applying the microscope for the direct microscopic observation in the field of medicine. It is uncertain weather the small worms were actually bacteria the reason was poor inadequate magnification quality of the microscope and so he perhaps observed blood cells only.
Robert Hooke (1635- 1703) and his micrographia-
Robert Hooke became the first applied microscopist of note while he was the curator of experiment for a royal society of London. Robert Hooke spend many hours using his compound microscope to examine various materials, and he presented his observation at meetings of a Royal society .There enthusiastic response encouraged him to publish(1665) his( Robert Hooke ) observation in a Book titled micrographia .
In this first reported observation of a moulds, Robert Hooke likened the observed knobs to the common spore-bearing cups of the common white mushroom. These insight was remarkable since both the Knobs and the caps of a mushroom contains spores, which are asexual reproductive cells of a mould that can grow into new individuals.
Antony Van Leeuwenhoek and his microscope:
In 1676,in Delft, Holland,Antony Van Leeuwenhoek,a successful linen merchant,was the first to observe the mysterious and exciting World of a microorganism for the next 50 years aunty his death in 1723 live in continue to arch microorganism with the end of a small simple(one-lensen) microorganism. Althogh the compound microscope had already been invented by Hans and Zacharias Janssen, Leeuwenhoek from his device more suitable for observing specimens with a transmitted light.
This was because his lenses provided greater details or resolving power. The magnifying power of his early instruments ranges from approximately 50 to 300 times the diameter of a particular specimen.Leeuwenhoek’s position in the development of a microbiology has been from the established because of his remarkable observation and description of a microscopic forms of a life.
He is an ending curiosity lead him to spend hours upon hours examining specimens collected from lakes and rain barrels and even from his own teeth and those of others. Among his first observation where description of a protozoa and of the basic shapes of a bacteria, yeast and algae.Leeuwenhoek recognise the value of recording his observation.He Sent more than 200 hand return occasionally illustrated letters to the Royal society in London.
Meaning of these were translated into English and published. Because of his numerous observations and careful measurement and recording of a specimens, Leeuwenhoek is considered the father of bacteriology, hematology, histology, protozoology and other science for which the microscope is the main investigative tool.
After Leeuwenhoek’s death the study of a microorganism was neglected for sometimes. This was because of a difficulty in constructing better microscope and because many scientist still considered microorganism to be nothing more than oddities and were firm believers in the theory of a spontaneous generation.
Theory of a spontaneous generation (Abiogenesis)-
The theory of a spontaneous generation stated by Aristotle in 346 B.C. expressed a belief wickly held as a late as the 19th century -that life hold and did appear spontaneously from non living or decomposing matter.
They were constantly seeing what they taught where example of a such spontaneous snakes, frogs and related forms of a life apparently developing form the mode of river banks and magods and flies appearing in decaying food. Aristotle state that insects develop from morning dew and roating manual and that tapeworms arise from animal wastes.
This beliefs held by all Greek scholars accepted and expanded throughout the middle ages and until comparatively recent times. To day the theory of spontaneous generation seems absurd. Certainly it was product of inadequate observation and faulty deduction .
Neverthless ,it is important thought throughout the centuries- especially study of a disease and of a various natural process such as a fermentation. The relationship between the microorganism and disease disprove the concept of a spontaneous generation.
Francisco Redi’s and fly experiment:
One of the first to refuse the doctor in of a spontaneous generation or the naturalist and physician Francisco redi. Around 1665 he showed that maggots did not emerge spontaneously from putrified meat.Redi put meat into three separate jars. One of these was closed with the paper cover, another left uncovered and the third was covered with fine gauze.
Louis pasture and crucial blow:
In 1859,French naturalist Felix Pouchet claimed to have carried out experiments showing clearly that microbial growth could occur without contamination by air thereby providing renewed hopes for the supporters of spontaneous generation. About this time the studies of Pasture were becoming known and several other scientists began to recognise the roles of microorganism in wine and vinegar production (fermentation) and food spoilage (putrefaction) process.
Pasteur found small round and oval bodies that resembled the spores( reproductive structures ) of a plant. To show that the gun cotton not only stopped the passage of microorganism but contained these forms of a life as well, Pasture simply added a little of used filter to sterile meat infusion.Soon microbial growth appeared.Thus the Pasture confirmed that way in which microbes gained acess to nutrients and how they could be prevented from doing so.
Despite his obvious success was not fully satisfied. She had to perform what some regard as his most elegant experiment on the subject, namely, to show that microbe free air did not create life inorganic infusions. To prove his point pasure designed and used swan -neck or A- shaped neck flask.
Nutrient liquid media were placed in the flasks and both the flask and liquid contents were sterilized by boiling. Once this had been done no plugs of any type were used to prevent the passage of a microorganisms into these system. Although these system were open to the environment allowing the flow of air through the system no growth occured.
Because of the length and the band of a flask swan neck, microorganisms present in the year could not reach the main part of the flask. However if the top of a system were broken off or if a flask were tilt so that the steroid liquid nutrient ran into the exposed part of neck and then returned, Microbes soon appear in the fluids.
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