bacterial requirements temperature and oxygen. measurement of microbial growth cfu direct viable...
TRANSCRIPT
Bacterial Requirements
Temperature and Oxygen
Measurement of Microbial Growth
CFU Direct
Viable Plate Counts Serial Dilutions Pour Plate Spread Plate
Membrane Filtration Counting Chamber MPN (fecal, H20, food)
Indirect Turbidity Metabolic activity
Metabolic Classifications
Temperature Oxygen requirements pH Pressure Radiation
Growth Curve Labeled Phases Lag phase
Adaptive Start metabolism 1-3 days
Log phase Generation time doubles Most metabolically active
Stationary phase Growth = death
Death phase Requirements decrease Possible spore formation
Temperature Requirements
Temperature Experiment
4 TSA plates Label
Temperature 4 different settings
Wheel spoke pattern 5 Bacteria
4 SAB broth/Durham tube Temperature
4 different settings S. cerevisiae
Anaerobic Culture Methods
Oxygen Requirements
Obligate Aerobes Microaerophiles Aerotolerant anaerobes Obligate Anaerobes Facultative Anaerobes Capnophiles
BHI deeps
Brain/Heart infusion Melt Label
BHI Organism
Inoculate Pipette or loop Roll tube to distribute
Ice Bath Incubate @ 37°C
Fluid Thioglycollate Broth
Sodium thyioglycollate Reduction (redox) Pink if oxidized
Label tubes Thio Organism
Inoculate with loop Incubate @ 37°C
Gas Pack Jar: CO2 anaerobic System
NaHCO3, NaBH4
H2O added to envelope toProduce H2 and CO2
H2 + O2 => H2O
TSA agar plate4 quadrantsLabel bacteriaLabel O2
Aerobic / Anaerobic Lab Test Results
aerobe FA aerotolerant anaerobe
Physical Requirements: Temperature Psychrophile
Unsaturated FA in cell membrane
Cold temperatures Psychrotroph (facultative
psychrophiles) Refrigeration Room temperature
Mesophile Warm Blooded Animals
Thermophile/Hyper- Saturated FA in cell
membrane
Bacterial Examples: Temperaturepsychrophile psychrotroph
mesophile thermophile
E coli
mold Vibrio
Archaea
Oxygen Requirement Classification
BHI results
Thio Tubes
Bacterial Examples of O2 Groups Obligate Aerobes
Pseudomonas Microaerophiles
H. pylori Aerotolerant aerobes
Streptococcus Lactobacillus
Obligate Anaerobes Clostridium
Facultative Anaerobes E. coli Stapylococcus
Capnophilic Campylobacter
E coli
Staph
pH Groups
Acidophile Bacillus acidocaldarius Lactobacillus acidophilus
Neutrophile E. coli Staphylococcus aureus
Akaliphile Streptococcus
pneumoniae Nitrobacter sp.
Questions?