• History
• Microbiology, sanitation, and medicine [and beer] have been intertwined for as long as humans
have been paying attention.
• We’ve been washing ourselves, our clothes, our dishes, and a number of other things.
• Boiling, scrubbing, animal fat soap, we’ve had these forever.
• Antiseptics & disinfectants are something newer.
• Basic Principles
• Sterilization – Killing or removal of all [micro]organisms and viruses in a material or on an
object.
• Not always attainable or practical.
• Sometimes it is essential.
• Disinfection – Reducing the number of pathogenic organisms in a material or on an object
such that there is no threat of disease.
• Disinfectants – For inanimate objects.
• Antiseptics – For living tissue.
• “Natural” Death rate is exponential and still is when treated with such agents.
• Microbes differ in their susceptibility.
• Bacteriocide vs. Bacteriostasis
• Chemical Antimocrobial Agents
• Potency
• Time
• Temp
• pH
• Concentration
• Evaluation
• Phenol Coef
• Filter paper
• Use-Dilution
• Phenol Coefficient
• A unit going back to 1867 when Joseph Lister introduced phenol as a disinfectant.
• Testing against Salmonella typhi and Staphylococcus aureus.
• <1.0 = Less effective than phenol
• 1.0 = Equal to phenol
• >1.0 = More effective than phenol
• Has limitations.
• D-value?
• Filter Paper Method
• Simpler than the phenol coefficient.
• Soak a filter paper in a disinfectant and place it on an iolculated plate.
• Does a wider circle mean more potency? Maybe.
• Molecules move differently in agar.
• Presence of other materials (like blood) may have differential effects.
• Use-Dilution Test
• Almost as simple as the filter paper method.
• Microbiology, sanitation, and medicine [and beer] have been intertwined for as long as humans
have been paying attention.
• We’ve been washing ourselves, our clothes, our dishes, and a number of other things.
• Boiling, scrubbing, animal fat soap, we’ve had these forever.
• Antiseptics & disinfectants are something newer.
• Basic Principles
• Sterilization – Killing or removal of all [micro]organisms and viruses in a material or on an
object.
• Not always attainable or practical.
• Sometimes it is essential.
• Disinfection – Reducing the number of pathogenic organisms in a material or on an object
such that there is no threat of disease.
• Disinfectants – For inanimate objects.
• Antiseptics – For living tissue.
• “Natural” Death rate is exponential and still is when treated with such agents.
• Microbes differ in their susceptibility.
• Bacteriocide vs. Bacteriostasis
• Chemical Antimocrobial Agents
• Potency
• Time
• Temp
• pH
• Concentration
• Evaluation
• Phenol Coef
• Filter paper
• Use-Dilution
• Phenol Coefficient
• A unit going back to 1867 when Joseph Lister introduced phenol as a disinfectant.
• Testing against Salmonella typhi and Staphylococcus aureus.
• <1.0 = Less effective than phenol
• 1.0 = Equal to phenol
• >1.0 = More effective than phenol
• Has limitations.
• D-value?
• Filter Paper Method
• Simpler than the phenol coefficient.
• Soak a filter paper in a disinfectant and place it on an iolculated plate.
• Does a wider circle mean more potency? Maybe.
• Molecules move differently in agar.
• Presence of other materials (like blood) may have differential effects.
• Use-Dilution Test
• Almost as simple as the filter paper method.
