Microbial Growth Control

• Growth Inhibition• Sterilization• Bacteriostatic• Bactericidal• Disinfectants

Heat

• Sterilization• Decimal Reduction

Time• Spores• Denaturation

Sterilization

• Autoclave• 121 C, 15 lb, 15 min• Moist heat• Dry Heat• Higher

temperatures• 160 C, 2 hrs

Pasteurization

• Flash Pasteurization

• 71 C, 15 seconds

• Bulk Pasteurization

• 63-66 C, 30 min

Cold SterilizationRadiation

• Gamma radiation

• UV light, X-rays

Filter Sterilization

• Filter Sterilization• Depth Filters

– HEPA– 99.9% of 0.3 μm

• Membrane (Millipore) Filters

• Nucleopore Filters

Ethylene Oxide

Gas Sterilization

Sterilants

Packaged plastics

Antimicrobial Agents

• Bactericidal• Fungicidal• Viricidal

• Selective Toxicity

Measuring Activity

• Minimum inhibitory Concentration

• Tube Dilution• Agar (Disk) Diffusion

Antiseptic

Disinfectant

Sanitizers

Organic Material

neutralizes

Chemotherapeutic Agents

Paul Ehrlich

• Chemist in Koch’s Lab

• Staining• “Magic Bullet”• Agent 606 • Salvarsan

Target Sites for Antibiotics

Growth Factor Analogs:

- Sulfanilamide –

Folic Acid Synthesis

- Sulfa Drugs

Quinolones – DNA Gyrase

Isoniazid

Worldwide Production of Antibiotics

Antibiotics

-Produced by Microorganisms

-Narrow vs. Broad Spectrum

-500 metric tons/yr

-Natural vs.

-Semisynthetic

Lactam Antibiotics

Lactam Ring• Penicillin G• Semisynthetic

Penicillin– Ampicillin– Methicillin

• Cephalosporin

Aminoglycosides

• Protein Synthesis Inhibitors

• Gram Negative Bacteria

• Streptomycin – TB• Kanamycin,

Gentamicin, Neomycin

Other Antibiotics

• Macrolides – Erythromycin

• 11% worldwide• Legionellosis

• Tetracyclines• First Broad spectrum

Other Antibiotics contd

DaptomycinCytoplasmic membranes

PlatensimycinFatty acid synthesis

Antiviral Drugs

• Nucleos(t)ide Analogs

• Protease inhibitors• Poor Selective

Toxicity???• Interferon

Rhinovirus

Influenza Antiviral agents

• Amantidine– Viral uncoating

• Osetltamvir– Tamiflu

• Zanamivir– Relenza– Neuraminidase

Chromosomal Resistance

R Plasmids

Conjugative

Drug Misuse

20% justified, 80% given, 50% not correctly used

Antibiotic Resistance

Search for New Antibiotics

New Analogstetracylcines, penicillins

Combinational ChemistryComputer Design

SaquinavirNatural Products

PlatensimycinDrug CombinationsBacteriophage

Growth Control Word List

Growth Inhibition

Sterilization

Bacteriostatic

Bactericidal

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

Growth Control Word List 2

Antimicrobial Agent

Bactericidal, Fungicidal,

Viricidal

Selective Toxicity

Minimum Inhibitory Conc.

Tube Dilution

Agar Diffusion Method

Antiseptic

Disinfectant

Chemotherapeutic Agents

Paul Ehrlich – Magic Bullet

Agent 606 - Salvarsan

Growth Factor Analogs

Sulfa Drugs

Sulfanilamide Folic Acid Synthesis

Quinolones

Antibiotics

Broad-Spectrum Antibiotic

Growth Control Word List 3

β – Lactam Ring

Penicillins

Cephalosporins

Aminoglycosides

Streptomycin, Neomycin, Kanamycin, Gentamicin

Macrolides

Erythromycin

Tetracyclines

Antiviral Agents

Interferons

Nucleos(t)ide analogs

Protease Inhibitors

Fungal Control

Drug Resistance

Conjugative R Plasmids

Drug Misuse

Growth Control Word List 4

Search for New Drugs

New Analogs

Designer Drugs

04/20/23