Giggi:I believe citrus (especially lime) has some kind of enzyme that kills the diarrhea causing bacteria, at least to some extent.
No, citrus is acidic. At high enough concentrations it inhibits or kills bacteria.
In many cases the concentration is not high enough.
Cevichi would be an example where the concentration should be high enough, but I have never tested the pH of cevichi.
TwoBit