©M J Larkin Biological Sciences. The Queen’s University of Belfast. Microbiology Techniques A....
Transcript of ©M J Larkin Biological Sciences. The Queen’s University of Belfast. Microbiology Techniques A....
©M J Larkin Biological Sciences. The Queen’s University of Belfast.
Microbiology TechniquesMicrobiology Techniques
A. Pure culture techniquesPleomorphismKoch/Pasteur. Gelatin gives way to AGAR
A. Pure culture techniquesPleomorphismKoch/Pasteur. Gelatin gives way to AGAR
©M J Larkin Biological Sciences. The Queen’s University of Belfast.
Microbiology Techniques cont…..Microbiology Techniques cont…..
©M J Larkin Biological Sciences. The Queen’s University of Belfast.
Microbiology Techniques cont…..Microbiology Techniques cont…..
©M J Larkin Biological Sciences. The Queen’s University of Belfast.
Microbiology Techniques – Culturing microorganisms
Microbiology Techniques – Culturing microorganisms
©M J Larkin Biological Sciences. The Queen’s University of Belfast.
Microbiology Techniques cont….. Microbiology Techniques cont…..
B. Sterilisation.Physical. Chemical. Filtration.Kinetics of death. Usually FIRST ORDER.
logeNt =logeNo - kt k=death constant
B. Sterilisation.Physical. Chemical. Filtration.Kinetics of death. Usually FIRST ORDER.
logeNt =logeNo - kt k=death constant
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logeN
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©M J Larkin Biological Sciences. The Queen’s University of Belfast.
Microbiology Techniques cont…..Microbiology Techniques cont…..Thermal death point. 10ml for 10 minutes
E.coli vegetative cells 55oC Bacillus sp spores 120oC
Decimal reduction time. Time to kill 90%.C. Use of Heat.
50 - 70oC vegetative cells. PASTEURISATION.100oC Some spores and viruses.110-120oC Most everything.AUTOCLAVE USUALLY 121oC 15psiMOIST/WET HEAT better than DRY HEAT OVENS
D. Radiation.UV, X rays, gamma radiation commonly used
Thermal death point. 10ml for 10 minutesE.coli vegetative cells 55oC Bacillus sp spores 120oC
Decimal reduction time. Time to kill 90%.C. Use of Heat.
50 - 70oC vegetative cells. PASTEURISATION.100oC Some spores and viruses.110-120oC Most everything.AUTOCLAVE USUALLY 121oC 15psiMOIST/WET HEAT better than DRY HEAT OVENS
D. Radiation.UV, X rays, gamma radiation commonly used
©M J Larkin Biological Sciences. The Queen’s University of Belfast.
Microbiology Techniques cont…..Microbiology Techniques cont…..E. Filtration.
Usually use 0.22 m pore cellulose acetate/nylon filters. Not effective for virus removal. They are filterable
F. Impaction.Physical force using striking action
G. Chemical agents.Phenol Disinfectant Phenol CoefficientHalogens Cl BrOxidants H2O2Alkylating agents FormaldehydeDetergentsMetals HgAlcohols
E. Filtration.Usually use 0.22 m pore cellulose acetate/nylon filters.
Not effective for virus removal. They are filterable
F. Impaction.Physical force using striking action
G. Chemical agents.Phenol Disinfectant Phenol CoefficientHalogens Cl BrOxidants H2O2Alkylating agents FormaldehydeDetergentsMetals HgAlcohols
DIRECTED READING: Practical manual.
Prescot. Ch2 Microscopy Ch5 Media. Ch6 Growth