Search results for " FTIR spectroscopy"
showing 10 items of 14 documents
Crypthecodinium cohnii Growth and Omega Fatty Acid Production in Mediums Supplemented with Extract from Recycled Biomass
2022
Crypthecodinium cohnii is a marine heterotrophic dinoflagellate that can accumulate high amounts of omega-3 polyunsaturated fatty acids (PUFAs), and thus has the potential to replace conventional PUFAs production with eco-friendlier technology. So far, C. cohnii cultivation has been mainly carried out with the use of yeast extract (YE) as a nitrogen source. In the present study, alternative carbon and nitrogen sources were studied: the extraction ethanol (EE), remaining after lipid extraction, as a carbon source, and dinoflagellate extract (DE) from recycled algae biomass C. cohnii as a source of carbon, nitrogen, and vitamins. In mediums with glucose and DE, the highest specific biomass gr…
Structure−Dynamics Coupling between Protein and External Matrix in Sucrose-Coated and in Trehalose-Coated MbCO: An FTIR Study
2004
We performed FTIR measurements on carboxy-myoglobin (MbCO) embedded in a sucrose−water matrix to study the degrees of freedom coupling between protein and external matrix in such a system. The work was undertaken on the light of recent results by Giuffrida et al. (J. Phys. Chem. B 2003, 107, 13211−13217), who evidenced, in trehalose-coated MbCO, a structured water−sugar environment of the protein, tightly coupled to the heme pocket structure. Such information was obtained through a suitable analysis of the temperature dependence of the CO stretching and of the water association bands in samples of different content of residual water. We applied here the same analysis to sucrose-coated MbCO.…
Role of residual water hydrogen bonding in sugar/water/biomolecule systems: a possible explanation fortrehalose peculiarity
2007
We report on the set of experimental and simulative evidences which enabled us to suggest how biological structures embedded in a non-liquid water–saccharide solvent are anchored to the surrounding matrix via a hydrogen bond network. Such a network, whose rigidity increases by decreasing the sample water content, couples the degrees of freedom of the biostructure to those of the matrix and gives place to protein–saccharide–water structures (protein–solvent conformational substates). In particular, the whole set of data evidences that, while the protein–sugar interaction is well described in terms of a water entrapment hypothesis, the water replacement hypothesis better describes the sugar–m…
Tolerance, Adaptation, and Cell Response Elicited by Micromonospora sp. Facing Tellurite Toxicity: A Biological and Physical-Chemical Characterization
2022
The intense use of tellurium (Te) in industrial applications, along with the improper disposal of Te-derivatives, is causing their accumulation in the environment, where oxyanion tellurite (TeO32−) is the most soluble, bioavailable, and toxic Te-species. On the other hand, tellurium is a rare metalloid element whose natural supply will end shortly with possible economic and technological effects. Thus, Te-containing waste represents the source from which Te should be recycled and recovered. Among the explored strategies, the microbial TeO32− biotransformation into less toxic Te-species is the most appropriate concerning the circular economy. Actinomycetes are ideal candidates in…
FDA dimension reduction techniques and components separation in Fourier-transform infrared spectroscopy
2020
FTIR spectroscopy is a measurement technique used to obtain an infrared spectrum of absorption of a solid (or a liquid or a gas), for the characterization of specific chemical components of materials. When repeated measures are taken on samples of materials, the result is a collection of spectra representing a set of samples from continous functions (signals) defined in the domain of the frequencies. An unifying approach to the study of a collection of FTIR spectra is proposed to deal with the presence of random shifts in the peaks, the identification of representative spectra and finally the characterization of the observed differences: in the functional data framework, the performance of …
Infrared Spectroscopy of Ruthenium Tetroxide and High-resolution analysis of the v3 band
2015
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Evaluation of mucoadhesive properties of α,β-poly(N-hydroxyethyl)-dl-aspartamide and α,β-poly(aspartylhydrazide) using ATR–FTIR spectroscopy
2002
Abstract The mucoadhesive properties of α,β poly( N -hydroxyethyl)- dl -aspartamide (PHEA) and α,β-polyaspartylhydrazide (PAHy) have been investigated using attenuated total reflection infrared (ATR–FTIR) spectroscopy. In particular, films based on these polymers have been contacted with a mucin solution at pH 7 and, the interfacial interaction and interpenetration between the glycoprotein and PHEA or PAHy have been studied by analysing the ATR–FTIR spectra. A diffusion model using a solution of Ficks' second law has been employed to determine the diffusion coefficient of water into polymeric films as a consequence of interdiffusion which occurs at the polymer film/mucin solution interface.
Infrared Spectroscopy In Urolithiasis In Children
2014
Chromophore-Protein Interplay During the Phytochrome Photocycle Revealed by Step-Scan FTIR Spectroscopy
2018
Phytochrome proteins regulate many photoresponses of plants and microorganisms. Light absorption causes isomerization of the biliverdin chromophore, which triggers a series of structural changes to activate the signaling domains of the protein. However, the structural changes are elusive, and therefore the molecular mechanism of signal transduction remains poorly understood. Here, we apply two-color step-scan infrared spectroscopy to the bacteriophytochrome from Deinococcus radiodurans. We show by recordings in H2O and D2O that the hydrogen bonds to the biliverdin D-ring carbonyl become disordered in the first intermediate (Lumi-R) forming a dynamic microenvironment, then completely detach …