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pH indicating plates - (Mar/11/2002 )

I am looking for a way to grow E. coli on plates that contain  pH indicator, in such a way that I can detect colonies that cause a drop in pH in the surrounding media.  The more sensitive, the better.  Any sugestions?


Contact me at; We shall discuss; Even I am also interested in pH based microbial screening.


as far as i know you can use nearly every pH-indicatorsubstance as long as its concentration is in a more or less non-toxic range, let's say 0,001.0,005%(w/v) as far as i know. The choice of indicator is then a function of your acid or base turnover.


PH level = 7.1


Phenol red is a good choice for an indicating plate. It shifts from red (alkaline) to yellow (acid) at about pH 7.0


what specifically are you trying to learn? there are some enterobacterial selective media available already on which e coli can grow, that select by pH (among other things)