Ortho-hydroxyl effect and proton transfer via ion-neutral complex: the fragmentation study of protonated imine resveratrol analogues in mass spectrometry

2016 ◽  
Vol 51 (7) ◽  
pp. 518-523 ◽  
Author(s):  
Lei Yue ◽  
Jing Li ◽  
Xiaodong Xie ◽  
Cheng Guo ◽  
Xinchi Yin ◽  
...  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kajsa Roslund ◽  
Markku Lehto ◽  
Pirkko Pussinen ◽  
Kari Hartonen ◽  
Per-Henrik Groop ◽  
...  

AbstractWe have measured the volatile fingerprints of four pathogenic oral bacteria connected to periodontal disease and dental abscess: Porphyromonas gingivalis (three separate strains), Prevotella intermedia, Prevotella nigrescens and Tannerella forsythia. Volatile fingerprints were measured in vitro from the headspace gas of the bacteria cultured on agar. Concrete identification of new and previously reported bacterial volatiles were performed by a combination of solid phase microextraction (SPME) and offline gas chromatography–mass spectrometry (GC–MS). We also studied the effect of the reduced electric field strength (E/N) on the fragmentation patterns of bacterial volatiles in online proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS). We aimed to discover possible new biomarkers for the studied oral bacteria, as well as to validate the combination of GC–MS and PTR-MS for volatile analysis. Some of the most promising compounds produced include: 1-Methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ), indole, and a cascade of sulphur compounds, such as methanethiol, dimethyl disulphide (DMDS) and dimethyl trisulphide (DMTS). We also found that several compounds, especially alcohols, aldehydes and esters, fragment significantly with the PTR-MS method, when high E/N values are used. We conclude that the studied oral bacteria can be separated by their volatile fingerprints in vitro, which could have importance in clinical and laboratory environments. In addition, using softer ionization conditions can improve the performance of the PTR-MS method in the volatile analysis of certain compounds.


PLoS ONE ◽  
2011 ◽  
Vol 6 (5) ◽  
pp. e20419 ◽  
Author(s):  
Federico Brilli ◽  
Taina M. Ruuskanen ◽  
Ralf Schnitzhofer ◽  
Markus Müller ◽  
Martin Breitenlechner ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document