For my science experiment I used yogurt and then put artificial sweeteners into a nutrient agar petri dish to see if it kills the bacterial colonies. We have kept the petri dishes in a warm room for about 1 week sealed with para-film, however barely any of the colonies are growing(even on the controlled). Is there any advice you can give?
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Bacteria Won't Grow In Petri Dishes. HELP!
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Re: Bacteria Won't Grow In Petri Dishes. HELP!
Hi Ppriya,
Welcome to Science Buddies! Your project sounds very interesting, though you should consider that there are a variety of factors that could be keeping your bacteria from growing. I would recommend looking through a website like this (https://m.wikihow.com/Grow-Bacteria-in-a-Petri-Dish) to get a better understanding of what might have gone wrong and if you missed any crucial steps. If you’re going off the Science Buddies project “Is That Really Bacteria Living in My Yogurt?” or a similar project (https://www.sciencebuddies.org/science- ... ogurt#help), try referring back to it and see if there’s anything you missed.
I would also recommend going through these Science Buddies resources: a previous Ask an Expert post on bacteria not growing properly (viewtopic.php?t=13149) and this document titled “Why Won’t My Cultures Grow?” (https://www.sciencebuddies.org/science- ... oblems.pdf) to see if you can pinpoint the problem.
From what I’ve gathered looking through these resources, bacteria takes about 4-6 days to grow and you’ve had then in the Petri dishes for a week, so give it sometime and maybe the bacteria will grow.
I don’t know enough about growing cultures in agar myself to give you advice but I hope these resources prove to be useful. Let us know if you have any follow up questions or concerns and we’d be more than happy to help!
Neha
Welcome to Science Buddies! Your project sounds very interesting, though you should consider that there are a variety of factors that could be keeping your bacteria from growing. I would recommend looking through a website like this (https://m.wikihow.com/Grow-Bacteria-in-a-Petri-Dish) to get a better understanding of what might have gone wrong and if you missed any crucial steps. If you’re going off the Science Buddies project “Is That Really Bacteria Living in My Yogurt?” or a similar project (https://www.sciencebuddies.org/science- ... ogurt#help), try referring back to it and see if there’s anything you missed.
I would also recommend going through these Science Buddies resources: a previous Ask an Expert post on bacteria not growing properly (viewtopic.php?t=13149) and this document titled “Why Won’t My Cultures Grow?” (https://www.sciencebuddies.org/science- ... oblems.pdf) to see if you can pinpoint the problem.
From what I’ve gathered looking through these resources, bacteria takes about 4-6 days to grow and you’ve had then in the Petri dishes for a week, so give it sometime and maybe the bacteria will grow.
I don’t know enough about growing cultures in agar myself to give you advice but I hope these resources prove to be useful. Let us know if you have any follow up questions or concerns and we’d be more than happy to help!
Neha
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Re: Bacteria Won't Grow In Petri Dishes. HELP!
Hi!
Neha K6 has given you some great tips! I'd like to add on with a few tips regarding your actual agar plates. What is your source of bacteria? You need to plate some bacteria (either a pure culture purchased online from places like Carolina Biological or random bacteria from a surface) in order for you to see bacterial colonies. Did you pour them yourself? If they weren't thick enough, you might not be able to see bacteria. Additionally, as Neha said, it might just be a matter of time. I hope this helped!
Thanks, probiotics
Neha K6 has given you some great tips! I'd like to add on with a few tips regarding your actual agar plates. What is your source of bacteria? You need to plate some bacteria (either a pure culture purchased online from places like Carolina Biological or random bacteria from a surface) in order for you to see bacterial colonies. Did you pour them yourself? If they weren't thick enough, you might not be able to see bacteria. Additionally, as Neha said, it might just be a matter of time. I hope this helped!
Thanks, probiotics