RESUMEN
Enzymatic oxidation of ferulic acid catalyzed by oxidases (laccase and peroxidase) was carried out. Ferulic acid was shown to be subjected to oxidative processes leading to the formation of oligomeric and polymeric structures. The polymer formation takes place due to the formation of CAr-CAr-, and CAr-O-CAr-bonds, as well as due to reactions of opening of the propane chain double bond. Different dynamic conditions of the enzymatic reactions were used to study the effects of conditions on the biosynthesis in vitro of some dehydropolymers: the method of dropwise mixing (endwise polymers) and a single addition (bulk polymers). The chemical structures of the resulting compounds were examined by the methods of IR, 1H NMR, and 13N NMR spectroscopy. Differences in the quantitative ratio of structural fragments in a polymer cause changes in its thermal characteristics.
Asunto(s)
Ácidos Cumáricos/química , Lacasa/química , Peroxidasa/química , Polímeros/síntesis química , Catálisis , Peróxido de Hidrógeno/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Oxidación-Reducción , Oxidorreductasas/química , Polímeros/química , Espectrofotometría InfrarrojaRESUMEN
The investigation of microbiological succession and changes in the enzymatic activity, temperature, pH, and phytotoxicity of lignin during its composting showed that the addition of a starter culture (a specially developed association of microorganisms) affects degradational succession in the compost pile. The process of composting can be monitored either microbiologically or biochemically, by measuring the activity of some enzymes. The compost is ready for use when the activity of oxidoreductases (particularly polyphenol oxidases) falls and the activity of invertase stabilizes at a certain level.
Asunto(s)
Conservación de los Recursos Naturales , Lignina/análisis , Eliminación de Residuos/métodos , Glicósido Hidrolasas/metabolismo , beta-FructofuranosidasaRESUMEN
Composting of hydrolytic lignin by a microbial association changed its molecular-weight composition, acid-based properties, and supramolecular structure. Specifically, by the end of the third month of composting, an increase was observed in its exchange capacity and the amount of negative charges, as well as in the content of phenyl, hydroxyl, and carboxyl groups. The use of this compost as a fertilizer for barley growth demonstrated that the changes increased the biological activity of hydrolytic lignin.
Asunto(s)
Lignina/química , Lignina/metabolismo , Biodegradación Ambiental , Hordeum/efectos de los fármacos , Hordeum/crecimiento & desarrollo , Concentración de Iones de Hidrógeno , Hidrólisis , Lignina/farmacología , Sustancias Macromoleculares , Peso MolecularRESUMEN
To correct defects of the body's phagocytic system, the authors used experimental agents, such as vital activity products of plant cells, which were obtained by biotechnology. These included arabinogalactan, syringin, K-212, and DFEGP. The study agents activate the oxidative metabolism of macrophages, the production of active forms of oxygen, and thus enhance its bactericidal effect against Yersinia pseudotuberculosis. Syringin and arabinogalactan produce a more pronounced stimulating macrophageal effect in Yersinia pseudotuberculosis phagocytosis than do K-212 and DFEGP. The findings indicate that further studies of the effects of these tested and other agents on humoral and cellular immunity are required.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Fagocitosis/efectos de los fármacos , Yersinia pseudotuberculosis/fisiología , Animales , Galactanos/farmacología , Glucósidos/farmacología , Cobayas , Técnicas In Vitro , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/microbiología , Fenilpropionatos/farmacología , Polisacáridos/farmacologíaRESUMEN
The possibility of the use of xylanase preparations for hydrolysing hemicelluloses in a non-bleached kraft pulp in order to facilitate its bleaching was studied. The effects of enzymatic preparations of the fungal and bacterial origins were examined, and the optimal conditions for xylanase activity were determined. UV spectroscopy demonstrated that the treatment of kraft pulp with the enzymatic preparations containing xylanase facilitated the subsequent removal of lignin and increased the brightness by 5%. The effect of enzymatic treatment was retained in the case of peroxide bleaching. The enzymatic preparations studied are promising for the development of chlorine-free pulp bleaching technologies.
Asunto(s)
Celulosa/metabolismo , Hojas de la Planta/metabolismo , Madera , Xilosidasas/metabolismo , Celulosa/química , Fermentación , Espectrofotometría Ultravioleta , Xilano Endo-1,3-beta-XilosidasaRESUMEN
Microbial assemblages were composed for composting hydrolysed lignin. Data on bioconversion of aromatic compounds with various types of substitution in the ring were used for this purpose. Composting of hydrolysed lignin reduced the contents of lignin, low-hydrolyzable polysaccharides, resins, and low-molecular-weight phenols and resulted in accumulation of humic acids. The resulting compost showed no phytotoxicity.