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
7.1.2 Culture Methods of Microorganisms Be divided into two major categories depending on the requirement of oxygen aerobic cultivation anaerobic cultivation Be divided into two major categories depending on the physical peculiarity of culture medium: liquid cultivation solid cultivation
7.1.2 Culture Methods of Microorganisms Be divided into two major categories depending on the requirement of oxygen： aerobic cultivation anaerobic cultivation Be divided into two major categories depending on the physical peculiarity of culture medium： liquid cultivation solid cultivation
7.1.3 Aerobic cultivating methods 1)Solid aerobic cultivating methods Solid cultivation in the test tube and petri dish
1) Solid aerobic cultivating methods Solid cultivation in the test tube and petri dish 7.1.3 Aerobic cultivating methods
Solid culture of mushroom
Solid culture of mushroom
2)Aerobic liquid cultivating methods ■面 Shaking incubator
2） Aerobic liquid cultivating methods Shaking incubator
Small-scale automatic fermentor for lab use
Small-scale automatic fermentor for lab use