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Domingues R.M.A.,University of Aveiro | Sousa G.D.A.,RAIZ Forest and Paper Research Institute | Silva C.M.,University of Aveiro | Freire C.S.R.,University of Aveiro | And 2 more authors.
Industrial Crops and Products | Year: 2011

The chemical composition of the lipophilic extracts of the inner and outer bark fractions of Eucalyptus grandis and Eucalyptus urograndis (E. grandis× Eucalyptus urophylla) cultivated in Brazil and Eucalyptus maidenii, cultivated in Portugal was studied by gas chromatography-mass spectrometry. The extracts were shown to be mainly composed of triterpenic compounds (along with mono and sesquiterpenes in E. maidenii) followed smaller amounts of fatty acids, fatty alcohols, and aromatic compounds. Triterpenic acids (mainly ursolic, betulinic and oleanolic acids), are particularly abundant in outer barks representing 5.2 g/kg, 5.7 g/kg and 9.3 g/kg in E. urograndis, E. grandis and E. maidenii outer barks, respectively. Although these compounds were found in considerably smaller amounts than those previously reported for Eucalyptus globulus, the total amounts of bark generated every year in South American pulp mills using E. urograndis and E. grandis, as well as the growth potential of E. maidenii plantations, the bark residues from these species are obvious candidates for the extraction of valuable triterpenic compounds. © 2010 Elsevier B.V. Source


Martins P.F.,University of Aveiro | De Melo M.M.R.,University of Aveiro | Sarmento P.,RAIZ Forest and Paper Research Institute | Silva C.M.,University of Aveiro
Journal of Supercritical Fluids | Year: 2016

The supercritical extraction of stalks and leaves of Eichhornia crassipes was carried out using pure and modified carbon dioxide. Preliminary results evidenced that the influence of temperature is weaker than pressure and ethanol content, and thus a design of experiments was performed in the ranges of 200-300 bar and 0.0-5.0 wt.% ethanol. The optima conditions for total extraction yield (ηTotal) were 250-300 bar and 5.0 wt.% of cosolvent, while for sterols yield (ηTotalSterol) they were 300 bar and 2.5 wt.%. The latter conditions were also the most favorable to maximize the concentration of total sterols in the extracts (CTotalSterol), particularly stigmasterol (CStigm), the most abundant one. For the referred optima, ηTotal = 1.25 wt.%, ηTotalSterol = 0.35 wt.%, CTotalSterol = 38.26 wt.%, and CStigm = 26.35 wt. %. This study showed also that the individual trends of stigmasterol and cholesterol were closer to the total sterols fraction behavior than β-sitosterol did, and also that the sterols concentration were higher in the first 2 h of extraction. In the whole, this article provides a pertinent contribution for the valorization of E. crassipes biomass through the production of natural extracts with high contents of sterols, especially stigmasterol, mainly if one takes into account it is classified as the most problematic invasive plant worldwide. © 2015 Elsevier B.V. All rights reserved. Source


Domingues R.M.A.,University of Aveiro | Sousa G.D.A.,RAIZ Forest and Paper Research Institute | Freire C.S.R.,University of Aveiro | Silvestre A.J.D.,University of Aveiro | Neto C.P.,University of Aveiro
Industrial Crops and Products | Year: 2010

The chemical composition of the lipophilic extracts of Eucalyptus globulus harvesting residues and bark generated by the pulp industry was studied by gas chromatography-mass spectrometry. Triterpenoids, mainly triterpenic acids with lupane, ursane and oleanane skeletons (namely, betulonic, betulinic, ursolic, oleanolic, 3-acetylursolic and 3-acetyloleanolic acids) were the major components detected. Triterpenoids contents range from 1.2 g/kg to 121.1 g/kg in fruits and surface layers of branches bark residues, respectively, being the triterpenic acids highly concentrated in surface layers of E. globulus biomass. The results demonstrate that these biomass residues can be considered as promising sources of valuable bioactive chemicals, opening new strategies to up-grade the pulp industry residues, within an integrated biorefinery context. The exploitation viability of the bark from an industrial pulp mill debarking process was evaluated. The recovery of triterpenoids from bark samples collected along the industrial debarking line decreases substantially, showing that a successful exploitation process of these valuable compounds in an integrated way will require the development of modifications on the debarking systems. © 2009 Elsevier B.V. All rights reserved. Source


Domingues R.M.A.,University of Aveiro | Patinha D.J.S.,University of Aveiro | Sousa G.D.A.,University of Aveiro | Sousa G.D.A.,RAIZ Forest and Paper Research Institute | And 5 more authors.
Cellulose Chemistry and Technology | Year: 2011

A comparative study on the triterpenic acids composition of the outer barks of several Eucalyptus species (E. globulus, E. grandis, E. urograndis, E. maidenii and E. nitens) is reported. The contents of the main triterpenic acids identified in the five species varied between 4.5 g/kg in E. urograndis and 21.6 g/kg in E. nitens. It has been observed that, out of these Eucalyptus species outer barks, those from temperate and Mediterranean zones, namely E. nitens and E. globulus, are richer in triterpenic acids than the species from sub-tropical and tropical regions. Furthermore, E. globulus outer bark is clearly the richest in ursane acids, while E. nitens outer bark is the richest in oleanane and lupane acids. biorefinery, Eucalyptus nitens, Eucalyptus grandis, Eucalyptus urograndis (Eucalyptus grandis x Eucalyptus urophylla),. Source


Araujo J.A.,RAIZ Forest and Paper Research Institute | Borralho N.M.G.,BorralhoIdea Consulting | Borralho N.M.G.,University of Lisbon | Borralho N.M.G.,Instituto Investigacao Cientifica Tropical | Dehon G.,RAIZ Forest and Paper Research Institute
Tree Genetics and Genomes | Year: 2012

The paper investigates the importance of additive and non-additive genetic variances for growth in Eucalyptus globulus (Tasmanian Blue Gum), based on a large collection of diameter growth data covering 40 sites and more than 4,200 genotypes, most of them cloned, and spanning three generations of breeding. The variance estimates were based on a model accounting for additive, full-sib family and clone within full-sib family terms. The results indicated a small amount of additive genetic variance for diameter(ĥ 2=0.10) and although non-additive genetic variance was also small, it accounted for a significant proportion of the total genetic variance present, corresponding to 80% of the additive variance. The interpretation of these non-additive effects is difficult. The results suggest, however, a possible role of epistasis. The evidence for this came from a strong observed bias in additive variance when clone effects were removed from the model and a larger than expected variance due to full-sib families relative to the variance due to clones within family. The relatively large proportion of genetic variance for growth that seems to be due to non-additive genetic effects has obvious implications in the breeding and deployment options in eucalypts, and these are briefly discussed. © 2011 Springer-Verlag. Source

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