Unusual structures on NGM plate — contamination or precipitate?

Model Organism: Worms Scientific Discussion
1

Hi everyone,
I’m seeing these unusual branching/crystalline-looking structures and small particles on my NGM plates. I use NA22 spread across the plate. I kept the plate at 37°C for 24 hours, but the structures did not grow or noticeably change. Could this be precipitate/debris, bacterial material, or contamination? Has anyone seen something similar?

I’ve attached two microscope images. Any suggestions would be appreciated!

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6dceebaa-4966-46a2-9ce0-18435889b1d41030×627 20.8 KB

2

Hi Sakhawat,

I have seen those crystallizations before as well. I believe they are some component of the agar mix that is crystallizing. Maybe the liquid agar was not properly heated during autoclaving, leaving the salts still clumped together. But I am not sure.