History and Development of Microbiology

History and Development of Microbiology

 }1220-1292; Roger Bacon postulated – disease is produced by invisible living creatures
}1483-1553; Fracastoro also suggested the same
}1632-1723; Antony van Leeuwenhoek of Holland observed and described microbes accurately as animalcules
}He constructed a simple microscope composed of double convex lens with magnification of 50-300 times
}1673; He sent a detailed letter about his findings to the Royal Society of London

Spontaneous Generation Vs. Biogenesis
}Spontaneous generation: living organism could develop from non-living matter e.g. maggots could be produced by exposing meat to warmth and air
}1626-1697; Francesco Redi suggested that meat did not produce maggots spontaneously. However,  flies, attracted towards meat, laid eggs producing maggots
}In 1749, John Needham observed the appearance of bacteria in meat and again supported abiogenesis
}1729-1799; Lazaro Spallanzani boiled beef broth and sealed the flask è There was no origin of microbes. But this experiment failed to convince Needham who insisted air is essential for origin of microbes
}1815-1873; Franz Schulze passed air through strong acid solution into boiled broth è microbes did not appear
}1810-1882; Theodor Schwann passed air through red hot tubes into broth è microbes did not appear
}About 1850; H. Schroder and T. von Dusch passed air through cotton into flask è microbes did not appear
}1822-1895; Louis Pasteur ended the argument and supported the BIOGENESIS
}He prepared a flask with long narrow gooseneck opening
}Nutrient solution was heated in the flask but microbes did not appear (germs settled in the gooseneck)

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