miles and misra calculations/pour plate technique calculations help - cell biology (Jun/07/2006 )

i was wondering if anyone knew the method used to calculate the number of psychrophilic bacteria from the plates in the miles and misra technique?

also the method used to calculate the number of mesophilic bacteria from the plates incubated at 37c from the miles and misra technique?



for the pour plate technique i am having trouble with i have averaged the three counts but i am being asked to calculate the viable count for the sample. this i dont understand what is the calculation i have to use an i am also asked to plot a log10 value on the growth curve graph how do i get this? a step by step with an example would be helpfull.

could someone get back to me regarding this plz thank you.

Nicky, you may like this forum

I would ask you what you already know. 'viable' is not a type of technique; 'viable' sort of means 'alive'...as in, viable counts are a count of bacteria that were able to hit the plate and divide into colonies...the colonies you were able to count. non-viable bacteria may have been present in your inoculum, but they would not result in colonies and they would probably die soon after plating (not all the cells in a culture are in the same growth phase, some will be closer to death, you see that?)

for a logarithmic graph, Excel is your best friend there...do you know what data you are showing on each axis?

It seems you are struggling a little bit with this class (your other post too ). does the manual suck, or what? is your TA unhelpful?

you may find help at sites like this oneand this, even though they may not seem initially to be helpful, read through and you can find some good stuff