Fig. 5. Photos of C. sporogenes endospores dyed with DAPI following 0 and 60 min of
thermal and high-pressure treatment. (A) 90
C and 600 MPa; (B) 90
C. (i), phase
contrast microscopy; (ii) fluorescence microscopy to detect DAPI fluorescence.
Photographs shown are representative of results observed in multiple photographs
taken for each treatment, with each photograph showing several dozen of endospores
exhibiting the same behaviour as those shown. The fluorescence intensities of the five
endospores per treatment were integrated and standardized against background
interference and vegetative cell controls for each photo. Comparable results were
obtained with endospores of C. beijerinckii (data not shown).