this presentation about factors affecting microbial growth

1. SUBMITTED BY:
M.Narayani
I MSC Microbiology
SUBMITTED TO:
Ms.A.Kathija banu &
Ms. Saajida sultaana mahusook
Dept. of Microbiology &
Biotechnology

2. Factors affecting the microbial growth
Requirement for microbial growth:
Physical requirement
Chemical requirement

3. Physical requirement:
Temperature
PH
Oxygen
Osmotic pressure/Salt tolerence
Chemical requirement:
Carbon
Nitrogen
Sulphur
Phosphorus
Trace elements
Organic growth

4. Temperature
Psychrophiles
Cold loving bacteria
15-20⁰c
Obligate psychrophiles
Not grow above 20⁰c
Eg:Bacillus globisporus
Facultative psychrophiles
Grow best below 20⁰c
Can also grow above
Eg:Xanthomonas

5. Mesophiles
25-40⁰c
Eg:all human pathogens
Thermophiles
Heat loving
50-60⁰c
Obligate thermophiles
Only grow at above 37⁰c
Eg:Archea,Eubacteria
Facultative thermophiles
Grow above & below 37⁰c

6. PH
Three types:
Acidophiles
PH:(0.1-5.4)
Eg:Lacto bacillus
Neutrophiles
PH:(5.4-8.0)
Eg:Bacterial pneumonia
Alkaliphiles
PH:(7.0-11.5)
Eg:Agrobacterium