Slide 1 Controlling Microbial GrowthLecture 10 ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Slide 2 Learning Outcomes• The language of Sterilization• Molecular Targets for disinfectants• Non-chemical methods of sanitization• Chemical disinfectants ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________Slide 3 Killing Microbes• Disinfection – Killing vegetative cells– Non-living surfaces• Sanitization– Lower microbial counts– cutlery• Degerming– Swabbing skin before shot• Antisepsis– Disinfection of living tissue• Sterilization– Surgical instruments ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Slide 4 Killing Terminology• ~ide– Death to microbes• ~stat or stasis– Stop population growth without killing living cells•Sepsis – Greek putrid ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________Slide 5 Rate of Microbial Death ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Slide 6 Targets of Microbial Control Agents• Plasma Membrane– Alteration of permeability• Proteins– Denaturation– Enzyme inhibition• Nucleic Acids– Inability to replicate• Oxidizing – SH2group of cystine part of many enzymes– Oxidizing agents (Chlorox) denature these enzymes ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________Slide 7 Alcohol• 95%• Coagulation of outside surface proteins• 70%• Infiltrates cell• Denaturation by disruption of H bonds