Yesterday I couldn’t come in to check on the progress of my yeast, so today I’m catching up. Tomorrow I’m scheduling a time trial experiment to check the progress of hourly yeast growth. I’m expanding that experiment to include yeast growth in 50% D2O (mixed with DDW).

But that doesn’t mean nothing grew today. So let’s check out the 48 hour growth (going back to Saturday:

• The original D2O sample – at 120h (5 days) the absorbance is 2.944. Compare that with Saturday (2.497).
• The 2nd generation D2O sample – at 72h (3 days) the absorbance is 0.062. Compare that with Saturday (0.000)
• The 1st generation 50% D2O sample was 3.155 at 72h, compared to 0.490 on Saturday.

I also started a new second generation D2O sample. There hasn’t been significant growth in the original 2nd gen sample so I pulled a larger amount of culture from the 1st gen sample and put that in a new batch of D2O YPD:

• 9ml of fresh D2O YPD mixed with 1ml of D2O YPD culture.

And I followed suit with a second generation of 50% D2O:

• 5.5ml of D2O YPD, 5.5ml of DDW YPD, and 1ml of DDW YPD culture.

The reason for the extra volume of 50% D2O is that I read the pipette wrong and added 5.5ml instead of 4.5ml of YPD broth. Oh well.

To better track the growth, I took so t=0h readings:

• 99% D2O YPD (2nd generation) – 0.618
• 50%D2O YPD (2nd generation) – 0.610

So as you can see, my mistake actually put the starting culture absorbance counts at about the same number. That works well and it’ll help better gauge 24h growth.

Until tomorrow…

50/50-72