bio.display

yesterday I prepared the following experiments:

• 100ml liquid culture as control in a 500ml Erlenmayer flask, composed of:
  • Nutrient Broth: 8g/1000ml -> 0.8g
  • NaCl: 30g/1000ml -> 3g
  • Glycerol: 10g/1000ml -> 1g
  • CaCO3: 5g/1000ml -> 0.5g
• 100ml of the same liquid culture, placed on a magnetic stirrer
• 100ml of the same liquid culture, but without CaCO3
• 100ml of the same liquid culture, but without  Glycerol

and left these overnight on the table at room temperature (well, lab temperature, around 20C)

today I’ve found that:

• the control was producing light when shaken
• the culture without the CaCO3 was producing light when shaken
• the culture without Glycerol was producing light when shaken
• the culture on the magnetic stirrer is constantly producing light, with the light visible around the vortex of stirring

thus it seems that a minimalist nutrient liquid without CaCO3 and/or Glycerol might already be sufficient