Microbiology Safety

1. Microbiology Safety • Microbes are present everywhere. • Harmful microbes should not be allowed to grow and develop • PRECAUTIONS • All surfaces should be plastic • All surfaces should be disinfected • Do not allow hands in contact with face • Wear protective clothing • Sterilise all equipment if possible (heat treatment)

2. What can go wrong • E Coli and other bacteria like Streptococcus can cause diseses like Necrotizing Fascitis

3. Growing Micro-Organisms • Need a suitable growth media e.g AGAR • AGAR: A substance extracted from red algae (often found in seaweed) • Agar usually comes as a powder which is dissolved in water - forms a gel. • Heated above 100oC (in an autoclave) to destroy contaminants and melt the gel. • Molten agar is then poured into petri dishes. • Agar provides lots of nutrients but is not degraded.

4. Avoiding Contamination • All containers have to be sealed ( e.g lids, tape etc) to prevent entry of contaminants • All equipment in contact with microbes have to be boiled or ‘flamed’. • No food or drink allowed in laboratory. • Once completed all dishes and cultures should be disposed of in sealed bags and autoclaved.

5. Resistant Spores • Some microbes can protect themselves by producing spores. • Spores are resistant to extremes in temp, moisture, and pH, or use of disinfectants that would kill most microbes. • They protect themselves with a thick outer coat. • Only temps over 120oC can kill all spores.