Yeast: role of yeasts in fermentation. Sour Wine "sick wine" Microorganisms as the agents of change. In 1857 he wrote a paper on the souring of milk by bacteria and he implied that microorganisms were related to human illness.
Concluded that agent for fermentation is yeast; agent for change to sour wine/milk is bacteria
He set down the foundation for the Germ Theory of Disease. He showed that where disease rampant, the air was full of microorganisms, but where disease was uncommon, the air was clean. He conducted his own exp. S-shaped neck (Swan-neck) flask.
Daughter Jeanne died from Typhoid Fever which is caused by Salmonella typhi
Pasteur verified the proof of the germ theory (by Koch) and gone a step further, he reported that bacteria were temp-sensitive, because chicken didn't acquire anthrax (via Bacillus anthracis
) at their normal body temp (42 C), but did so when the animals were cooled to 37 C.
- In 1880: The basis for the use of vaccine
- experimented with inoculations of chicken by cholera Vibrio cholerae). Tried to develop enfeebled (weakened with acidic solution) bacteria. Injected weakened Vibrio cholerae to chickens; then exposed chickens to live Vibrio cholerae; chickens did NOT develop cholera.
In 1881, he applied the principle to anthrax to protect sheep against disease. In 1885, Pasteur reached the zenith of his career: he immunized a young boy against the rabies disease.
Pasteur died in l818