Team:Paris Bettencourt/Notebook/Idli and micro-organisms

July 2nd to 9th



I experiented different recipes to make idli come from India. I tried to do it with different rice and lentill (called dall in india). Finally, I chose to do this recipe with basmati rice and indian dall.

July 12th to 14th and 16th to 18th



I did grow ''Saccharomyce cerevisiae'' with mCherry and geneticin resistance genes in idli. I added 2 ml of a yeast growth solution (YPD) with an OD600 of 0.455 (around 1.2 x 107 cfu) after the soaking phase and the mixing and grinding of rice and dall together.The first try was to see if there are the fermentation process will this laboratory strain. After the fermentation time, I had plated the µorganisms come from the butter phase (middle phase between water on the top, and grind matter in the bottom of the erlenmeyer) on YPD with geneticin. I observed a lot of part of crush rice or dall, and just few colonny, not red like expected with the mCherry gene. The second try was more successful. This time I diluated the butter 10 and 100 time before plating, always on YPD and geneticin. I observed few colonies for the plate with the 100th and around 30 with the 10th.

July 29th



Test of the titration protocol with spectrophotometer for the Vitamin A (protocol titration)
I tested this protocol and tried to calibrate it. I used, like food sample, 1g of rice and I did 8 bottles with 8 different concentrations of pure vitamin A from 10 -1 to 10 -8 mg.ml-1.

Results :
We can just observe concentrations higher than 10-3mg.ml-1.