Chitin and Cellulose Processing in Low-Temperature Electron Beam Plasma

Abstract

Polysaccharide processing by means of low-temperature Electron Beam Plasma (EBP) is a promising alternative to the time-consuming and environmentally hazardous chemical hydrolysis in oligosaccharide production. The present paper considers mechanisms of the EBP-stimulated destruction of crab shell chitin, cellulose sulfate, and microcrystalline cellulose, as well as characterization of the produced oligosaccharides. The polysaccharide powders were treated in oxygen EBP for 1–20 min at 40 °C in a mixing reactor placed in the zone of the EBP generation. The chemical structure and molecular mass of the oligosaccharides were analyzed by size exclusion and the reversed phase chromatography, FTIR-spectroscopy, XRD-, and NMR-techniques. The EBP action on original polysaccharides reduces their crystallinity index and polymerization degree. Water-soluble products with lower molecular weight chitooligosaccharides (weight-average molecular mass, Mw = 1000–2000 Da and polydispersity index 2.2) and cellulose oligosaccharides with polymerization degrees 3–10 were obtained. The 1H-NMR analysis revealed 25–40% deacetylation of the EBP-treated chitin and FTIR-spectroscopy detected an increase of carbonyl- and carboxyl-groups in the oligosaccharides produced. Possible reactions of β-1,4-glycosidic bonds’ destruction due to active oxygen species and high-energy electrons are given.

The efficacy and safety of cold atmospheric plasma as a novel therapy for diabetic wound in vitro and in vivo

“…There were several kinds of reactive ions, molecules, and free radicals, such as atomic oxygen (O), hydroxyl (OH), nitrogen molecule (N2), super oxide anion (O2−), and NO, in the plasma . It was reported that these reactive agents played an important role in the interaction between the plasma and cells .…”

Chitosan Plasma Chemical Processing in Beam-Plasma Reactors as a Way of Environmentally Friendly Phytostimulants Production

“…Mass-spectrometer HALO 201-RC (Hiden Analytical, Warrington, UK) continuously monitored plasma generating medium composition. In particular, it could detect possible gaseous pollutants emitted by chitosan under the plasma treatment [42]: the total gas flow G1 + G2 must be sufficient to neglect these pollution exhausts. To prevent the plasma generating medium from pollution by residual air the working chamber was preliminary evacuated to a pressure of ~1 Pa after every reactor reloading and only then the chamber was filled with oxygen of spectroscopic grade (Scientific Industrial Center of National Research Center "Kurchatov Institute", Moscow, Russia), which was used in the most exper- Algorithms of the EB controller operation were preliminary optimized by numerical simulation of the EB propagation and absorption in aerosols.…”

“…IR spectral measurements in a wavenumber range 500-5000 cm −1 with a resolution of 4 cm −1 were carried out by a FT-IR spectrometer Perkin-Elmer Spectrum 100 (Perkin-Elmer, Waltham, MA, USA) as described in [37,42].…”

Influence of Dielectric Barrier Discharge Treatment on Surface Structure of Polyoxymethylene Fiber and Interfacial Interaction with Cement

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