Effects of Chlorine Dioxide on Spore Structural and Fuctional Properties

摘要

One major barrier to the development of new spore decon technologies is that killing assays take 36-48 hours to perform and require a tedious culture-based assessment of spore viability. Spore sterilization assays can require from seven to twenty one days of incubation in growth medium. We proposed that near-real time optical spore germination assays could be developed into a new type of spore killing assay. The experimental results described in this report were designed to test this hypothesis. Dormant bacterial endospores are highly birefringent due to the anhydrous nature of the spore cytoplasm. Once spores are triggered to germinate by small molecules such as sugars, nucleosides or amino acids, a series of very rapid enzymic reactions occur that leads to the hydrolysis of spore integuments and the rehydration of the spore cytoplasm. The germination process is accompanied by a concomitant 30 - 50% decrease in visible wavelength optical absorbance. Real-time spore germination kinetics can be acquired spectrophotometrically. We report here a comparative analysis of spore killing by several sporicides using established viability assays, live/dead fluorescent microscopy, rapid spectrophotometric and automated scanning microscopic methods.