Fourier transform infrared spectroscopy of dental unit water line biofilm bacteria

Abstract

Abstract. Fourier transform-infrared (FT-IR) spectroscopy has become an important tool for rapid analysis of complex biological samples. The infrared absorbance spectrum could be regarded as a "fingerprint" which is a feature of biochemical substances. The FT-IR spectra of fresh and stored dried samples of six bacterial isolates (Klebsiella sp., Bacillus cereus, Bacillus subtilis, Pseudomonas aeruginosa, Achromobacter xylosoxidans and Achromobacter sp.) were observed by variation in sample preparation. The results indicated that variation in sample preparation did not affect the spectra of isolates. However, less promiment/absence of a small shoulder peak at 1738 cm −1 was evident in fresh dried samples of Achromobacter sp. andA. xylosoxidans compared to prominent and broad shoulder band at 1724 cm −1 in stored dried samples of these two isolates. In addition to the established KBr pellet technique, attenuated total reflectance (ATR) spectroscopy was used to analyse the spectra of planktonic growth (−80 • C liquid cultures) and biofilm growth of six isolates. ATR spectroscopy of −80• C planktonic and biofilm growth showed variation in absorption spectra in fingerprint (1200-900 cm −1 ) region. Two clear absorption bands were prominent in biofilm at 1175 and 1143 cm −1 whereas, one prominent broad band at 1075 cm −1 resulting from the overlapping of two band was noted in planktonic cultures. Biofilm forming capability of the six isolates was also determined by acridine orange staining method. The microscopic analysis of biofilms formed on glass slides revealed the presence of a matrix of exopolysaccharides and microcolonies typical of biofilm architecture. Maximum biofilm formation was observed after 175 h in P. aeruginosa and Klebsiella sp.

Biogenic Synthesis, Characterization and Antibacterial Properties of Silver Nanoparticles against Human Pathogens

“…FTIR of P. aeruginosa AgNPs was performed to check the involvement of biological molecules. The bands present at 3261, 3061, 2947, 2358, 1338 and 1394 cm −1 corresponded to the stretching vibrations of alcohol (O-H) , primary amines (N-H) , alkane (C-H) , amine (C-N) and alcohol (C-O) groups respectively, as reported previously by Liaqat 35) and Kalyanasundaram et al 36) . The SEM data showed that silver nanoparticles are in spherical shape with average size of 40 nm.…”

Effects of Low Frequency-Low Voltage Alternating Electric Current on Apoptosis Progression in Bioelectrical Reactor Biofilm

“…The bands at 3,695, 1,622, 1,520, 1,124, 1,032, 914, 600, and 475 cm −1 can be used to distinguish hematite from biological structures. A small organic component is indicated by the bands for the -CH 3 and -CH groups (2,960, 2,869, 2,930, and 2,849 cm −1 ), which are evident in our FTIR analysis results of the fatty-acid region (Bosch et al, 2006;Liaqat, 2009). As Figure 4 shows the attached biofilm on the electrodes are irreversible.…”

“…Additionally, variations in the fatty acid-region peak could indicate a biological change. Proteins (amide I, II, and III bands), nucleic acids (regions around 1,240 and 1,080 cm −1 ), polysaccharides (from 1,150 to 900 cm −1 ), and lipids (around 2,900 cm −1 ) are the main groups of biomolecules (Bosch et al, 2006; Liaqat, 2009;You et al, 2015) that can be associated with the observed bands. The strong band at 1,646 cm −1 observed in the biofilms may partially be the result of the H-O-H bending (ν2 mode) band of water.…”

Effect of Exo/Endogenous Prophylaxis Dentifrice/Drug and Cariogenic Conditions of Patient on Molecular Property of Dental Biofilm: Synchrotron FTIR Spectroscopic Study

“…A band of IR spectra from 1850 to 1350 cm −1 includes a band in the region of 1730 cm −1 that can be attributed to (>C=O) phospholipids, esters, fatty acids [ 28 , 29 , 43 , 48 ], and the characteristic region of proteins. Protein bands include Amide I (C=O stretch) vibrations in the region from 1675–1615 cm −1 , Amide II (60% N–H bend and 40% C–N stretch) vibrations in the region from 1575–1520 cm −1 , and Amide III (40% C–N stretch, 30% N–H bend) vibrations in the region from 1315–1270 cm −1 [ 28 , 29 , 41 , 42 , 43 , 45 ].…”