南京师范大学：《微生物学》课程PPT教学课件（英文版）Chapter 7 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?

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