Biotech Lab - Plant Extracts

Front 1

Collect stalk, root, or 5-10 leaves that contain potential antibiotic activity. Liquify in blender/homogenize in mortar and pestle. Collect 0.5mL in microcentrifuge tube. Use 70% ethanol for disinfectant sample.

Back 1

Step 1

Front 2

Label MHA-containing petri dish with the bacterial name. Make sure agar plates have dry surfaces

Back 2

Step 2

Front 3

Agitate E.coli broth culture by gently tapping tube. Aseptically transfer 1mL of the culture into sterile saline solution. Mix properly.

Back 3

Step 3

Front 4

Aseptically pipet 100yL of bacteria into plate and advisor gently until surface becomes dry. This will serve as seeded plate/ lawn culture.

Back 4

Step 4

Front 5

Pick a sterile disc and dip into test samples. Drain saturated disc and place disc on iniculated agar plates.

Back 5

Step 5

Front 6

Gently press down on the discs with tip of sterile forceps on agar plate.

Back 6

Step 6

Front 7

Repeat steps 5 and 6 for rest of test samples.

Back 7

Step 7

Front 8

Place discs for each test sample in equidistant positions on seeded MHA surface. Mark underside of plate to indicate reference points (which disc contains which solution)

Back 8

Step 8

Front 9

Wrap plate with paper and incubate plate upside down at 37°C for 18-24 hra.

Back 9

Step 9

Front 10

Repeat steps 2 - 9 for S. Aureus.

Back 10

Step 10

Front 11

Observe plates. Qualitatively determine if E. Coli and S. Aureus are susceptible.

Back 11

Step 11

Front 12

Store the bacterial plates at refrigerated temperature in inverted position.

Back 12

Step 12