Fluorescence-based discrimination of vegetative cells of bacillus strains from Escherichia coli and Saccharomyces cerevisiae

In the search for a healthy indoor climate, chemical cleaning agents are replaced by bacillus strains to create an ecosystem in which these harmless bacteria clean surfaces consuming organic molecules dust and dirt. To optimise ecosystems, it is important monitor bacterial growth activity, but reference methods time involve serious delay. Therefore, potential of fluorescence spectroscopy monitoring activity was investigated this study. We confirmed that signals could be detected Bacillus vegetative cells at load above 108 mL−1. As emission mostly 330–400 nm range after excitation 280–290 range, we attribute signal tryptophan residues. The distinguished from those released pure l-tryptophan, plate count agar medium, spores, were classified with 100% accuracy PLSDA. comparison other microbes, strains, Escherichia coli (MG1655) Saccharomyces cerevisiae found produce indistinguishable peak 340 response 280 nm. However, using hybrid multivariate classifier involving PCA combined One-Class SVM on area-normalised spectra allowed footprints identified classification 78%.