Science Buddies: "Ask an Expert"

Hi I was doing a science experiment that relates to this one. I was wondering: After the bacteria ships, in what temperatures do we need to keep the bacteria in to prevent it from perishing. I was wondering about this because i would not do my experiment immediately after we get the bacteria

I would also like for someone to more thoroughly go over how we place the bacteria in the cups and expose them to the UV light.. Thanks

Hello,

For storing the bacteria, usually you can store bacterial cultures short-term at a temperature of 4 degrees Celsius (about the same temperature as a typical refrigerator). These may be able to be stored for several days with little loss of viability. Please double check your order as they should give you some instructions as to how to properly store the bacteria to retain maximum viability.

As for plating the bacteria, you will need to take a specified amount of the suspension (see the link https://www.sciencebuddies.org/science- ... #materials) and spread the bacteria across the agar plate using a spreader. Before exposing them to UV light, you can cover half of the plate with aluminum foil, so that you can test two conditions using one plate as explained in the procedure for the experiment.

Please let us know if you have further questions.

Best,
Pharma

Thank you for your response Pharma, it was very helpful.

I have one more question:
As I have access to an incubator, I wish to check it every day after school (approx. 24 hrs.)
In what temperature should I leave it to ensure that the bacteria is proper (as in science buddies standards)

Essentially, I am asking for the recommended Time Stored: Incubator Temperature ratio

Thanks,
Shreyas Iyer

Hello,

Do you know if the incubator at school is set to a certain temperature already, or are you allowed to change it?

In the procedure link it states 37C for an overnight culture. See link below
https://www.sciencebuddies.org/science- ... #procedure.

However, you may want to test out a few different temperatures to avoid overgrowth. I would test a range of temperatures between 32C and 37C. Good Luck on your project!

Hi, I just wanted to agree with AJ that bacteria are usually grown at 37 degrees Celsius, and also mention that you should try to keep the environment where you're working as sterile as possible. If it's not sterile, you will likely start growing bacteria from the environment. You can use 70% ethanol or isopropanol (rubbing alcohol) to wipe down the counter and your lab gloves.