Chapter 7 Microbial Growth How to cultivate microorganisms? How microorganisms grow? What factors affect the microbial growth? (Requirements for microbial growth) How to control the microbial growth?
Chapter 7 Microbial Growth How to cultivate microorganisms? How microorganisms grow? What factors affect the microbial growth? (Requirements for microbial growth) How to control the microbial growth?
7.1 Measurement of microbial growth 7.1.1 Isolation of pure cultures In natural habitats microorganisms usually grow in complex, mixed populations containing severals pieces.This presents a problem for microbiologist because a single type of microorganism cannot be studied. One needs a pure culture,a population of cells arising from a single cell,to characterize a individual species
7.1 Measurement of microbial growth 7.1.1 Isolation of pure cultures In natural habitats microorganisms usually grow in complex, mixed populations containing severals pieces. This presents a problem for microbiologist because a single type of microorganism cannot be studied. One needs a pure culture, a population of cells arising from a single cell,to characterize a individual species
Isolation of pure microorganisms: spread-plate method
Isolation of pure microorganisms: spread-plate method
Spread culture method by dilution 1.0ml 1.0ml 1.0ml 1.0ml Original 9 ml H,O 9 ml H,O 9 ml HO 9ml HO sample (10-1 dilution) (10-2 dilution) (10-3 dilution) (10-4 dilution) 1.0ml 1.0ml Mix with warm agar and pour
Spread culture method by dilution
Streak plate method
Streak plate method