A composite of bacterial cellulose and lignin for a healing of incurable wounds

Biofilm-forming multi-drug resistant pathogens may account for 10% of all hospital acquired infections and can occur in burns, post-surgical wounds, pressure injuries and diabetic foot wounds. Hydrogels – natural polymers or composite materials – represent both a bandage and a matrix for therapeutics in a wound healing. Novel composite based on bacterial cellulose and synthetic analog of lignin - DHP (dehydrogenate polymer) has been designed with the aim to suppress pathogenic agents in incurable wounds. The FT-IR spectra of the BC/DHP membrane established an appearance of characteristic for DHP absorption bands in the composite in the 1600–1510 cm−1 spectral range. A clear position of these bands in BC/DHP showed that DHP had been incorporated into the BC polymeric matrix. In addition, disappearance of the bands at the 3630–3650 cm−1 spectral range assigned to the cellulose free OH vibration, strengthening the bands assigned to intermolecular interactions and an appearance of a new band at 3293 cm−1 could serve as a proof of the interaction of BC molecules and DHP. Micrographs obtained from a scanning electron microscopy proved the dose-dependent interaction of DHP with BC, which resulted in a decrease of the pore number in the cellulose membrane. The antimicrobial activity of composites BC/DHP were tested the in vitro experiments, using Pseudomonas aeruginosa (УМВ-100) (MTT-test) and showed that BC/DHP inhibited P. aeruginosa. BC/DHP composite will be promising hydrogel for a healing of infected incurable wounds.Integrative Biology and Medicine : October 2-7, 2017, Kyiv, Ukraine

Isotopic shifts of the low-energy excitations of interstitial oxygen in germanium

Abstract The rotational states of O in natural Ge as determined by phonon spectroscopy are found to be shifted in isotopically enriched Ge : O crystals. These shifts are larger than compatible with the line width in natural Ge if only the motion of the quasi-free Ge-O-Ge molecule is considered. Because of the reduced isotope scattering of the phonons in the enriched Ge the position of higher excited states could be determined. This allows to estimate the height of the axial potential barrier by extending to Ge : O the Yamada-Kaneta model for Si : O

Kombucha multimicrobial community under simulated spaceflight and martian conditions

Kombucha microbial community (KMC) produces a cellulose-based biopolymer of industrial importance and a probiotic beverage. KMC-derived cellulose-based pellicle film is known as a highly adaptive microbial macrocolony - a stratified community of prokaryotes and eukaryotes. In the framework of the multipurpose international astrobiological project "BIOlogy and Mars Experiment (BIOMEX)," which aims to study the vitality of prokaryotic and eukaryotic organisms and the stability of selected biomarkers in low Earth orbit and in a Mars-like environment, a cellulose polymer structural integrity will be assessed as a biomarker and biotechnological nanomaterial. In a preflight assessment program for BIOMEX, the mineralized bacterial cellulose did not exhibit significant changes in the structure under all types of tests. KMC members that inhabit the cellulose-based pellicle exhibited a high survival rate; however, the survival capacity depended on a variety of stressors such as the vacuum of space, a Mars-like atmosphere, UVC radiation, and temperature fluctuations. The critical limiting factor for microbial survival was high-dose UV irradiation. In the tests that simulated a 1-year mission of exposure outside the International Space Station, the core populations of bacteria and yeasts survived and provided protection against UV; however, the microbial density of the populations overall was reduced, which was revealed by implementation of culture-dependent and culture-independent methods. Reduction of microbial richness was also associated with a lower accumulation of chemical elements in the cellulose-based pellicle film, produced by microbiota that survived in the post-test experiments, as compared to untreated cultures that populated the film.This study was supported by National Academy of Sciences of Ukraine (grant 47/2012-15). The pre-flight programs EVTs and SVTs for the EXPOSE-R2 mission were supported by the European Space Agency.http://www.liebertpub.com/overview/astrobiology/992018-05-30hj2017Biochemistr

The first space-related study of a kombucha multimicrobial cellulose-forming community : preparatory laboratory experiments

Biofilm-forming microbial communities are known as the most robust assemblages that can survive in harsh environments. Biofilm-associated microorganisms display greatly increased resistance to physical and chemical adverse conditions, and they are expected to be the first form of life on Earth or anywhere else. Biological molecules synthesized by biofilm -protected microbiomes may serve as markers of the nucleoprotein life. We offer a new experimental model, a kombucha multimicrobial culture (KMC), to assess a structural integrity of a widespread microbial polymer - cellulose - as a biosignature of bacteria-producers for the multipurpose international project "BIOlogical and Mars Experiment (BIOMEX)", which aims to study the vitality of pro- and eukaryotic organisms and the stability of organic biomolecules in contact with minerals to analyze the detectability of life markers in the context of a planetary background. In this study, we aimed to substantiate the detectability of mineralized cellulose with spectroscopy and to study the KMC macrocolony phenotype stability under adverse conditions (UV, excess of inorganics etc.). Cellulose matrix of the KMC macrocolony has been mineralized in the mineral-water interface under assistance of KMC-members. Effect of bioleached ions on the cellulose matrix has been visible, and the FT-IR spectrum proved changes in cellulose structure. However, the specific cellulose band vibration, confirming the presence of beta(1,4)-linkages between monomers, has not been quenched by secondary minerals formed on the surface of pellicle. The cellulose-based KMC macrocolony phenotype was in a dependence on extracellular matrix components (ionome, viriome, extracellular membrane vesicles), which provided its integrity and rigidness in a certain extent under impact of stressful factors.https://link.springer.com/journal/110842018-06-30hj2017Business Managemen