Pekar, Miloslav* Dotaz Zobrazit nápovědu
The increasing numbers of kept horses create problems with processing horse manure as important local waste. This work was focused on horse manure vermicomposting in a real-field continuous-feeding system under controlled conditions, and on the complex study of the maturity and stability of the produced vermicompost. Commonly used simple indicators such as the C/N ratio, N-NH4+/N-NO3- ratio, DOC or ion exchange capacity, and also more advanced spectroscopic and thermoanalytic techniques were used and applied on the humic substances isolated from the vermicompost during its maturation (12 months in total). When compared with the original horse manure, vermicomposting decreased the aliphatic, protein-like, and polysaccharide humic components, whereas vermicomposting increased the aromaticity and contents of oxygen-containing functional groups. The typical tryptophan-like fluorophores in the manure, corresponding to the freshly produced organic matter of biological or microbial origin, were progressively transformed to humic-like fluorophores during vermicomposting. The most thermally labile humic fraction disappeared quickly during the very early vermicomposting stages. The results of spectroscopic and thermogravimetric analyses suggest that stable and mature vermicompost was produced after 6-9 months of vermicomposting, which was also supported by biologically-based maturity indicators.
Use of traditional sources of collagen such as pork, bovine, and carp has some limitations. Chicken skin can be valuable alternative. In this work collagen was isolated from chicken skin using a modified procedure. Molecular properties of chicken collagen were analyzed and compared to collagen from other animal skins. Acid-soluble collagen type I was obtained with a yield of 25% and water content around 67%. Viscosimetry and ultrasonic spectroscopy were newly used for molecular characterization. By ultrasonic attenuation measurements, a pre-aggregation phase in the interval from 20°C to 27°C was observed, which is a proof of disaggregation and liquefaction. From 40°C upward, the liquefaction process finishes and aggregation continues. In a bovine sample this phenomenon starts at 40°C, in chicken at 50°C, and continues until 70°C. By viscosimetry, the denaturation temperature was confirmed as 40°C for bovine and 50°C for chicken collagen. Chicken collagen has a two times higher lysine level than bovine, which provides molecular stability side-chain interactions. With regard to higher thermal stability and favorable amino acid composition, waste chicken skin has the potential to be an excellent alternative source of raw collagen with applications in the food industry and biomedicine.
- MeSH
- aminokyseliny analýza MeSH
- denaturace proteinů MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- kolagen chemie izolace a purifikace MeSH
- kur domácí * metabolismus MeSH
- kůže chemie MeSH
- prasata MeSH
- proteinové agregáty MeSH
- skot MeSH
- spektrální analýza MeSH
- stabilita proteinů MeSH
- ultrazvuk MeSH
- viskozita MeSH
- vysoká teplota MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
The purpose of this study was to specify critical parameters (physicochemical characteristics) of drug substance that can affect dissolution profile/dissolution rate of the final drug product manufactured by validated procedure from various batches of the same drug substance received from different suppliers. The target was to design a sufficiently robust drug substance specification allowing to obtain a satisfactory drug product. For this reason, five batches of the drug substance and five samples of the final peroral drug products were analysed with the use of solid state analysis methods on the bulk level. Besides polymorphism, particle size distribution, surface area, zeta potential, and water content were identified as important parameters, and the zeta potential and the particle size distribution of the drug substance seem to be critical quality attributes affecting the dissolution rate of the drug substance released from the final peroral drug formulation.
Self-balancing diffusion is a theoretical concept that restricts the introduction of extents of reactions. This concept is analyzed in detail for general mass- and molar-based balances of reaction-diffusion mixtures, in relation to non-self-balancing cases, and with respect to its practical consequences. Self-balancing is a mathematical restriction on the divergences of diffusion fluxes. Fulfilling this condition enables the proper introduction of the extents of (independent) reactions that reduce the number of independent variables in thermodynamic descriptions. A note on a recent generalization of the concept of reaction and diffusion extents is also included. Even in the case of self-balancing diffusion, such extents do not directly replace reaction rates. Concentration changes caused by reactions (not by diffusion) are properly described by rates of independent reactions, which are instantaneous descriptors. If an overall descriptor is needed, the traditional extents of reactions can be used, bearing in mind that they include diffusion-caused changes. On the other hand, rates of independent reactions integrated with respect to time provide another overall, but reaction-only-related descriptor.
- MeSH
- difuze * MeSH
- kinetika MeSH
- termodynamika MeSH
- Publikační typ
- časopisecké články MeSH
Molar balances of continuous and batch reacting systems with a simple reaction are analyzed from the point of view of finding relationships between the thermodynamic driving force and the chemical reaction rate. Special attention is focused on the steady state, which has been the core subject of previous similar work. It is argued that such relationships should also contain, besides the thermodynamic driving force, a kinetic factor, and are of a specific form for a specific reacting system. More general analysis is provided by means of the non-equilibrium thermodynamics of linear fluid mixtures. Then, the driving force can be expressed either in the Gibbs energy (affinity) form or on the basis of chemical potentials. The relationships can be generally interpreted in terms of force, resistance and flux.
- MeSH
- chemické modely MeSH
- fyzikální jevy MeSH
- kinetika MeSH
- techniky syntetické chemie metody MeSH
- termodynamika MeSH
- Publikační typ
- časopisecké články MeSH
CONTEXT: Adipose tissue distribution is a key factor influencing metabolic health and risk in obesity-associated comorbidities. OBJECTIVE: Here we aim to compare the proteomic profiles of mature adipocytes from different depots. METHODS: Abdominal subcutaneous (SA) and omental visceral adipocytes (VA) were isolated from paired adipose tissue biopsies obtained during bariatric surgery on 19 severely obese women (body mass index > 30 kg/m2) and analyzed using state-of-the-art mass spectrometry. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were performed to investigate proteome signature properties and to examine a possible association of the protein expression with the clinical data. RESULTS: We identified 3686 protein groups and found 1140 differentially expressed proteins (adj. P value < 0.05), of which 576 proteins were upregulated in SA and 564 in VA samples. We provide a global protein profile of abdominal SA and omental VA, present the most differentially expressed pathways and processes distinguishing SA from VA, and correlate them with clinical and body composition data. We show that SA are significantly more active in processes linked to vesicular transport and secretion, and to increased lipid metabolism activity. Conversely, the expression of proteins involved in the mitochondrial energy metabolism and translational or biosynthetic activity is higher in VA. CONCLUSION: Our analysis represents a valuable resource of protein expression profiles in abdominal SA and omental VA, highlighting key differences in their role in obesity.
- MeSH
- bariatrická chirurgie MeSH
- dospělí MeSH
- genové regulační sítě MeSH
- lidé středního věku MeSH
- lidé MeSH
- morbidní obezita metabolismus patologie chirurgie MeSH
- nitrobřišní tuk cytologie metabolismus patologie MeSH
- omentum cytologie metabolismus patologie chirurgie MeSH
- podkožní břišní tuk cytologie metabolismus patologie MeSH
- proteomika MeSH
- tukové buňky metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- pozorovací studie MeSH
- práce podpořená grantem MeSH
- Publikační typ
- abstrakt z konference MeSH
- MeSH
- finanční podpora výzkumu jako téma MeSH
- Publikační typ
- abstrakty MeSH
A freeze-drying method enabling solubilization of hydrophobic species in aqueous solutions of native hyaluronan is described. The method is based on opening the access to supposed hydrophobic patches on hyaluronan by disturbing its massive hydration shell. Hydrophobic and/or polarity-sensitive fluorescence probes were used as hydrophobic models or indicators of interactions with hydrophobic patches. Fluorescence parameters specific to individual probes confirmed the efficiency of the freeze-drying method. This work is the first step in developing biocompatible and biodegradable carriers for hydrophobic drugs with targeted distribution of the active compound from native, chemically non-modified hyaluronan.
- Publikační typ
- abstrakt z konference MeSH
