Fig. 4From: Rapid and simple detection of endospore counts in probiotic Bacillus cultures using dipicolinic acid (DPA) as a markerThe effect of different metal ions (a Na+, Ca2+, K+, Mg2+, Mn2+; b Cu2+, Fe2+, Fe3+, Al3+, Zn2+) at different concentrations (1000, 100, 10 and 0 μM) on the DPA fluorescence intensityBack to article page