Fourier Transform Infrared (FTIR) Spectroscopic Analyses of Microbiological Samples and Biogenic Selenium Nanoparticles of Microbial Origin: Sample Preparation Effects
Open Access
- 20 February 2021
- Vol. 26 (4), 1146
- https://doi.org/10.3390/molecules26041146
Abstract
To demonstrate the importance of sample preparation used in Fourier transform infrared (FTIR) spectroscopy of microbiological materials, bacterial biomass samples with and without grinding and after different drying periods (1.5–23 h at 45 °C), as well as biogenic selenium nanoparticles (SeNPs; without washing and after one to three washing steps) were comparatively studied by transmission FTIR spectroscopy. For preparing bacterial biomass samples, Azospirillum brasilense Sp7 and A. baldaniorum Sp245 (earlier known as A. brasilense Sp245) were used. The SeNPs were obtained using A. brasilense Sp7 incubated with selenite. Grinding of the biomass samples was shown to result in slight downshifting of the bands related to cellular poly-3-hydroxybutyrate (PHB) present in the samples in small amounts (under ~10%), reflecting its partial crystallisation. Drying for 23 h was shown to give more reproducible FTIR spectra of bacterial samples. SeNPs were shown to contain capping layers of proteins, polysaccharides and lipids. The as-prepared SeNPs contained significant amounts of carboxylated components in their bioorganic capping, which appeared to be weakly bound and were largely removed after washing. Spectroscopic characteristics and changes induced by various sample preparation steps are discussed with regard to optimising sample treatment procedures for FTIR spectroscopic analyses of microbiological specimens.Keywords
Funding Information
- Russian Foundation for Basic Research (17-08-01696-a, 16-08-01302-a)
This publication has 50 references indexed in Scilit:
- Identification and discrimination of bacteria using Fourier transform infrared spectroscopySpectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2013
- Fourier Transform Infrared Spectroscopy for Molecular Analysis of Microbial CellsMethods in Molecular Biology, 2012
- How the Plant Growth-Promoting Bacterium Azospirillum Promotes Plant Growth—A Critical AssessmentAdvances in Agronomy, 2010
- Monitoring of biomass composition from microbiological sources by means of FT‐IR spectroscopyBiotechnology & Bioengineering, 2009
- Responses of Azospirillum brasilense to Nitrogen Deficiency and to Wheat Lectin: A Diffuse Reflectance Infrared Fourier Transform (DRIFT) Spectroscopic StudyMicrobial Ecology, 2008
- Infrared and Raman spectroscopy and quantum chemistry calculation studies of C–H⋯O hydrogen bondings and thermal behavior of biodegradable polyhydroxyalkanoateJournal of Molecular Structure, 2005
- Melting behavior of poly(3-hydroxybutyrate) investigated by two-dimensional infrared correlation spectroscopySpectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2005
- Infrared Spectroscopy in MicrobiologyPublished by Wiley ,2000
- Effects of Azospirillum inoculation on root infection and nitrogen incorporation in wheatCanadian Journal of Microbiology, 1983
- A taxonomic study of the Spirillum lipoferum group, with descriptions of a new genus, Azospirillum gen. nov. and two species, Azospirillum lipoferum (Beijerinck) comb. nov. and Azospirillum brasilense sp. nov.Canadian Journal of Microbiology, 1978