12 documents found, page 1 of 2
New solvent-free method for isolating ellagic acid from sulphite spent liquor
Evtyugin, Dmitry D.; Prates, António; Domingues, M. Rosário; Casal, Susana; Evtyugin, Dmitry V.Ellagic acid (EA) is a plant polyphenol with wide potential in biomedical (e.g., anti-inflammatory, neuroprotective, and anti-melanogenic, among others) and technical applications such as copolymers, chelating reagents, ion-exchange resins and materials for electrochemical devices. Upon acid sulphite pulping of Eucalyptus wood, EA is partially dissolved in the spent liquor and adsorbed on the resulting pulp. In...
Effect of alkali charge on the performance of Eucalyptus globulus kraft pulps f...
Henriques, Ana; Evtyugin, Dmitry V.The present study aimed to evaluate the effect of active alkali charge, in kraft cooking of Eucalyptus globulus wood, on the properties of the laboratory-produced tissue paper. Eucalyptus wood chips were cooked under similar conditions at four different active alkali (AA) levels of 16, 19, 21, and 23 % and DEDED sequence was used for subsequent ECF bleaching. Pulps were analyzed for their intrinsic viscosity, c...
Improved bleached eucalyptus kraft pulp-based tissue papers incorporating wet-s...
Matos, Marina; Carta, Ana M.; Pinto, Paula C.; Evtyugin, Dmitry V.Common tissue paper manufacturing trends aim at partial or total replacement of softwood pulp with hardwood pulp for its production, such as bleached eucalyptus kraft pulp (BEKP), in order to optimize the process and the final product properties such as softness. However, the use of a single type of hardwood fiber results in lower strengths of both wet and dry webs. To maintain necessary strength and desired pr...
Characterization data of pulp fibres performance in tissue papers applications
Morais, Flávia P.; Bértolo, Raquel A. C.; Curto, Joana M. R.; Amaral, Maria E. C. C.; Carta, Ana M. M. S.; Evtyugin, Dmitry V.The data presented in this article are related to the original research paper entitled "Comparative characterization of eucalyptus fibres and softwood fibres for tissue papers applications" available in Materials Letter: X Journal [1]. In this article, six eucalyptus hardwood pulps and six softwood pulps were characterized in terms of morphological, chemical and water-related (by drainability and water retentio...
Tailoring the surface properties and flexibility of starch-based films using oi...
Gonçalves, Idalina; Lopes, Joana; Barra, Ana; Hernández, Diana; Nunes, Cláudia; Kapusniak, Kamila; Kapusniak, Janusz; Evtyugin, Dmitry V.Agrofood byproducts may be exploited as a source of biomolecules suitable for developing bioplastic materials. In this work, the feasibility of using starch, oil, and waxes recovered from potato chips byproducts for films production was studied. The recovered potato starch-rich fraction (RPS) contained an amylopectin/amylose ratio of 2.3, gelatinization temperatures varying from 59 to 71 °C, and a gelatinizatio...
Comparative characterization of eucalyptus fibers and softwood fibers for tissu...
Morais, Flávia P.; Bértolo, Raquel A. C.; Curto, Joana M. R.; Amaral, Maria E. C. C.; Carta, Ana M. M. S.; Evtyugin, Dmitry V.Significative growth and demanding for premium tissue products, in which softness and absorbency are key consumer requests, pointed out the need for the establishment of relations between fiber properties and tissue paper properties. For this purpose, an experimental plan was designed using a representative group of pulp fibers, six hardwood, and six softwood, for the production and characterization of low basi...
Effects of gamma irradiation and periodate oxidation on the structure of dextri...
Pereira, Isabel Sofia Melo; Simões, Joana; Evtyugin, Dmitry V.; Rouif, Sophie; Coimbra, Manuel A.; Domingues, M. Rosário M.; Gama, F. M.Sterilization of biomaterials by gamma irradiation should not change its structure, since this may affect also its bioactivity. In this work, dextrin and periodate-oxidized dextrin (ODEX), both irradiated and non-irradiated, were hydrolysed by -amylase and the obtained oligosaccharides were fractionated by ligand-exchange/size exclusion chromatography and analyzed by matrix-assisted laser desorption/ionization ...
Effects of gamma irradiation and periodate oxidation on the structure of dextri...
Pereira, Isabel; Simões, Joana; Evtyugin, Dmitry V.; Rouif, Sophie; Coimbra, Manuel A.; Domingues, M. Rosário M.; Gama, MiguelSterilization of biomaterials by gamma irradiation should not change its structure, since this may affect also its bioactivity. In this work, dextrin and periodate-oxidized dextrin (ODEX), both irradiated and non-irradiated, were hydrolysed by α-amylase and the obtained oligosaccharides were fractionated by ligand-exchange/size exclusion chromatography and analyzed by matrix-assisted laser desorption/ionization...
A novel approach for immobilization of polyhexamethylene biguanide within silic...
Sousa, Isabel; Maia, Frederico; Silva, Ana; Cunha, Angela; Almeida, Adelaide; Evtyugin, Dmitry V.; Tedim, João; Ferreira, Mário G.Antibacterial agents have been in the spotlight over the past few years either due to their extensive applications or for the increasing concern with the spreading of biocide resistance. The encapsulation of large spectrum antibacterial agents, that are human safe, has been proposed as an alternative to overcome some of these problems but also to impart a controlled release of the encapsulated material. Polyhex...
Development and application of a capillary electrophoresis method for the deter...
Costa, Elisabete V.; Lima, Diana L. D.; Evtyugin, Dmitry V.; Esteves, Valdemar I.A capillary zone electrophoresis (CZE) method for simple and rapid determination of ellagic acid (EA) in Eucalyptus globulus wood and in the filtrate from unbleached kraft pulp has been developed. This is the first application of CZE for the detection of EA in industrial streams from cellulosic pulp production. The EA determinations in wood extractives and in pulp filtrates were succeeded only after sample acid...