Analysis of bacterial strains with pyrolysis-gas chromatography/differential mobility spectrometry

Abstract

Eight vegetative bacterial strains and two spores were characterized by pyrolysis-gas chromatography with differential mobility spectrometry (py-GC/DMS) yielding topographic plots of ion intensity, retention time, and compensation voltage simultaneously for ions in positive and negative polarity. Biomarkers were found in the pyrolysate at characteristic retention times and compensation voltages and were confirmed by standard addition with GC/MS analyses providing discrimination between Gram negative and Gram positive bacterial types, but no recognition of individual strains within the Gram negative bacteria. Principal component analysis was applied using two dimensional data sets of ion intensity versus retention time at five compensation voltages including the reactant ion peaks all in positive and negative ion polarity. Clustering was observed with compensation voltage (CV) chromatograms associated with ion separation in the DMS detector and little or no clustering was observed with the reactant ion peaks or CV chromatograms where ion separation is poor. Consistent clustering of Gram positive B. odysseyi and Gram negative E. coli in both positive and negative polarities with the reactant ion peak chromatograms and key CV chromatograms suggests common but unknown common chemical compositions in the pyrolysate.

Empirical prediction of reduced ion mobilities of secondary alcohols

“…However, in recent years, ion mobility spectrometers are increasingly in demand for new applications specifically on biological samples (cells, fungi, bacteria) [3][4][5][6][7][8][9][10][11][12], in medicine (diagnosis, therapy and medication control e.g. from breath analysis) [3,4,13,14] and process control [15][16][17][18][19][20][21][22].…”

Analytical pyrolysis-based study on intra-skeletal organic matrices from Mediterranean corals

“…For all the tested corals, acetamide was the most abundant product of this class, followed by acetic acid. These [39,41] two compounds are both reported in the literature to be formed upon chitin pyrolysis; however, acetic acid is a common pyrolysis product obtained by several biopolymers such as wood [30] and humic matter [32], while acetamide is a typical product from pyrolysis of microbial cell walls [33] and could be formed upon pyrolysis of other precursors such as (3); mannosan (4); 1,6-anhydrogalactofuranose (5); levoglucosan (6); 1,6-anhydroglucofuranose (7); tetradecanoic (myristic) acid (8); C15 acids (9); hexadecanol (10); hexadecenoic acids (11); hexadecanoic (palmitic) acid (12); octadecen-9-ol (13); C17 acids (14); octadecanol (15); octadecenoic acid isomers (16); octadecanoic acid (17); monomyristin (18); eicosadienoic acids (19); eicosenoic acids (20); eicosanoic acid (21); monopalmitin (22); docosenoic acid (23); docosanoic (24); monostearin (25); tetracosenoic acids (26); tetracosanoic acid (27); hexacosanoic acid (28); cholestanol (29); octadocanoic (30). hexadecanoic acid, hexadecyl ester (31) thermally labile proteins [36].…”

“…thermally assisted hydrolysis and methylation) widely applied to fingerprinting the organic matter of living organisms, for instance, in the identification of bacteria [13,14] and fungi [15]. The application of analytical pyrolysis to the molecular characterization of organic matter involved in biomineralization has been reported for mollusks [16][17][18] and foraminifera [19].…”

Peak Detection Algorithm Based on Second Derivative Properties for Two Dimensional Ion Mobility Spectrometry Signals

“…Today ion mobility spectrometers are applied in process control [3][4][5][6][7][8][9], environmental and indoor air quality monitoring [10][11][12][13][14][15] and for medical and biological issues. In latter applications, the interest lies on the detection of biomarkers and metabolites for early diagnosis and for online medication control [16][17][18][19].…”