1. Aseptic Technique – Inoculating Different Types of Media
Key concepts:
Different types of bacterial cultures: broth, agar slant, and agar deep.
Aseptic transfer of bacteria from one type of culture medium to another.
Appropriate use of inoculating loops and needles.

2. Four Basic Forms of Bacterial Culture Media
Agar plate
Broth
Agar Deep
Agar Slant
Four Basic Forms of Bacterial Culture Media

3. Always use sterile instruments to transfer bacteria!
Loop and Needle

4. Flame loop before AND after using it

5. Other Sterile Transfer Instruments

6. “Little Finger Technique”

7. ....so far provided to us: NB or TSB

8. Today: You Inoculate Fermentation Tubes (G and L)
Contain:
Peptones and NaCl
COH of interest (0.5 – 1%)
Phenol red indicator ( alternate name “phenol red broth or PR broth”)
Used to differentiate Enterobacteriaceae among themselves and from other Gram-neg. rods.

9. ....so far provided to us: NA or TSA slant cultures
From left to right: Micrococcus luteus, Pseudomonas aeruginosa, E. coli

10. Today: You Inoculate Urea Agar Slants
Contain:
Peptones, glucose and potassium phosphate (as buffer to resist alkalinization due to peptone metabolism)
Urea
Phenol red

11. Also today: Use the Inoculating Needle to inoculate an agar deep
the end