Microbial Growth Control

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Microbial Growth Control

• Growth Inhibition
• Sterilization
• Bacteriostatic
• Bactericidal
• Disinfectants

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Heat

• Sterilization
• Decimal Reduction Time
• Spores
• Denaturation

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Sterilization

• Autoclave
• 121 C, 15 lb, 15 min
• Moist heat
• Dry Heat
• Higher temperatures
• 160 C, 2 hrs

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Pasteurization

• Flash Pasteurization
• 71 C, 15 seconds
• Bulk Pasteurization
• 63-66 C, 30 min

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Cold SterilizationRadiation

• Gamma radiation
• UV light, X-rays

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Filter Sterilization

• Filter Sterilization
• Depth Filters
• HEPA
• 99.9 of 0.3 µm
• Membrane (Millipore) Filters
• Nucleopore Filters

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Ethylene Oxide
Gas Sterilization Sterilants Packaged plastics
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Antimicrobial Agents

• Bactericidal
• Fungicidal
• Viricidal
• Selective Toxicity

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Measuring Activity

• Minimum inhibitory Concentration
• Tube Dilution
• Agar (Disk) Diffusion

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Antiseptic Disinfectant Sanitizers Organic
Material neutralizes Chemotherapeutic Agents
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Paul Ehrlich

• Chemist in Kochs Lab
• Staining
• Magic Bullet
• Agent 606
• Salvarsan

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Target Sites for Antibiotics
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Growth Factor Analogs - Sulfanilamide Folic
Acid Synthesis - Sulfa Drugs
Quinolones DNA Gyrase Isoniazid
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Worldwide Production of Antibiotics

• Antibiotics
• Produced by Microorganisms
• Narrow vs. Broad Spectrum
• 500 metric tons/yr
• Natural vs.
• Semisynthetic

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? Lactam Antibiotics

• ? Lactam Ring
• Penicillin G
• Semisynthetic Penicillin
• Ampicillin
• Methicillin
• Cephalosporin

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Aminoglycosides

• Protein Synthesis Inhibitors
• Gram Negative Bacteria
• Streptomycin TB
• Kanamycin, Gentamicin, Neomycin

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Other Antibiotics

• Macrolides Erythromycin
• 11 worldwide
• Legionellosis
• Tetracyclines
• First Broad spectrum

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Other Antibiotics contd
Daptomycin Cytoplasmic membranes Platensimycin
Fatty acid synthesis
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Antiviral Drugs

• Nucleos(t)ide Analogs
• Protease inhibitors
• Poor Selective Toxicity???
• Interferon

Rhinovirus
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(No Transcript)
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Influenza Antiviral agents

• Amantidine
• Viral uncoating
• Osetltamvir
• Tamiflu
• Zanamivir
• Relenza
• Neuraminidase

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Antibiotic Resistance
Chromosomal Resistance R Plasmids Conjugative Dru
g Misuse 20 justified, 80 given, 50 not
correctly used
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Search for New Antibiotics
New Analogs tetracylcines, penicillins Combinatio
nal Chemistry Computer Design Saquinavir Natural
Products Platensimycin Drug Combinations Bacterio
phage
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Growth Control Word List
Growth Inhibition Sterilization Bacteriostatic Bac
tericidal Disinfection Heat Sterilization Decimal
Reduction Time
Spores Autoclave 121 C, 15 lb, 15
Minutes Pasteurization 63-66 C for 30 Minutes 71
C for 15 Seconds
Radiation Filter Sterilization Depth
Filters Membrane (Millipore) Filters Nucleopore
Filter
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Growth Control Word List 2
Antimicrobial Agent Bactericidal, Fungicidal,
Viricidal Selective Toxicity Minimum
Inhibitory Conc. Tube Dilution Agar Diffusion
Method
Growth Factor Analogs Sulfa Drugs Sulfanilamide
Folic Acid Synthesis Quinolones Antibiotics Bro
ad-Spectrum Antibiotic
Antiseptic Disinfectant Chemotherapeutic
Agents Paul Ehrlich Magic Bullet Agent 606 -
Salvarsan
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Growth Control Word List 3
Macrolides Erythromycin Tetracyclines Antivi
ral Agents Interferons Nucleos(t)ide analogs
ß Lactam Ring Penicillins Cephalosporins Aminogl
ycosides Streptomycin, Neomycin, Kanamycin,
Gentamicin
Protease Inhibitors Fungal Control Drug
Resistance Conjugative R Plasmids Drug Misuse
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Growth Control Word List 4
Search for New Drugs New Analogs Designer Drugs