Name: Vanessa
Status: student
Grade: 9-12
Location: CA
Country: USA
Date: Fall 2011
Question:
My experiment involves the effect of serially diluted garlic extract on E. coli bacteria. My question is can I use a dropper to "drip" extract onto colonies of bacteria instead of the disk diffusion method to test the extract against E. coli?
NEWTON BBS does not recommend growing/culturing bacteria without the supervision of a microbiologist, and a properly equipped microbiology laboratory. Safety is our main concern! Growing dangerous bacteria species unknowingly is a real possibility and serious illness may occur without proper handling techniques. Furthermore, without proper bacterial disposal procedures such as an autoclave can guarantee, there is a danger to anyone who comes in contact after disposal.
Replies:
I would streak the bacteria onto the plate and add the liquid before incubating. You will need to leave the plates agar side down until the garlic solution absorbs into the plate. Then incubate the plates upside down. If the garlic solution inhibits growth, there will be a clear spot where the drop was introduced.
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