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1.
Int J Phytoremediation ; 24(14): 1533-1542, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35234104

RESUMO

Phytoextraction of trace elements (TE) using woody species is an economically challenging soil remediation approach because of the long time needed. Yet, some trees contain alkaloids that can be exploited along structural components to enhance biomass value. As alkaloids are thought to be involved in plant defence mechanisms, we hypothesized that potentially hostile phytoremediation conditions could increase their level. Camptothecin in Camptotheca acuminata and 1-deoxynojirimycin in Morus alba were measured from trees grown in a field in presence of Cu, Pb and Zn all together, and from M. alba grown in a greenhouse in presence of Cd or other abiotic stressors (NaCl and bending). The trees did not extract TE in the field, but M. alba stems accumulated Cd in the greenhouse experiment, with no consequence on stomatal conductance and leaves pigments concentration. Camptothecin and 1-deoxynojirimycin concentrations were preserved under all experimental conditions, as was biomass yield, and phenolics were slightly increased in M. alba exposed to TE. This study provides evidence that valuable and persistent alkaloids and phenolics can be extracted from trees facing phytoremediation-associated stresses, without a negative impact on their quantity and on biomass yield. Such products could generate a sustainable stream of revenues during phytoremediation.


There is scarce data on tree alkaloid content and scarcer data on how it is affected by exposure to trace elements in a phytoremediation context. We provide evidence that the content of two specific alkaloids is not altered in Morus alba and Camptotheca acuminata exposed to moderate to elevated levels of contaminating trace elements. The manuscript introduces the use of M. alba for phytoremediation in the Americas and is the first to propose the use of C. acuminata on trace element contaminated sites to produce camptothecin, a valuable anticancer alkaloid.


Assuntos
Camptotheca , Metais Pesados , Morus , Poluentes do Solo , Oligoelementos , Solo/química , Oligoelementos/análise , Biodegradação Ambiental , Poluentes do Solo/análise , Metais Pesados/análise , Cádmio , 1-Desoxinojirimicina , Árvores , Camptotecina
2.
Molecules ; 27(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35208976

RESUMO

The current practices regarding the procurement chain of forest industry sidestreams, such as conifer bark, do not always lead to optimal conditions for preserving individual chemical compounds. This study investigates the standard way of storing bark in large piles in an open area. We mainly focus on the degradation of the most essential hydrophilic and hydrophobic extractives and carbohydrates. First, two large 450 m3 piles of bark from Norway spruce (Picea abies) were formed, one of which was covered with snow. The degradation of the bark extractives was monitored for 24 weeks. Samples were taken from the middle, side and top of the pile. Each sample was extracted at 120 °C with both n-hexane and water, and the extracts produced were then analysed chromatographically using gas chromatography with flame ionisation or mass selective detection and high-performance liquid chromatography. The carbohydrates were next analysed using acidic hydrolysis and acidic methanolysis, followed by chromatographic separation of the monosaccharides formed and their derivatives. The results showed that the most intensive degradation occurred during the first 4 weeks of storage. The levels of hydrophilic extractives were also found to decrease drastically (69% in normal pile and 73% in snow-covered pile) during storage, whereas the decrease in hydrophobic extractives was relatively stable (15% in normal pile and 8% in snow-covered pile). The top of the piles exhibited the most significant decrease in the total level of extractives (73% in normal and snow-covered pile), whereas the bark in the middle of the pile retained the highest amount of extractives (decreased by 51% in normal pile and 47% in snow-covered pile) after 24-week storage.


Assuntos
Picea/química , Casca de Planta/química , Extratos Vegetais/química
3.
Anal Bioanal Chem ; 414(8): 2687-2698, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35075513

RESUMO

To enhance the characterization of wood extractives at molecular level, a detailed ultrahigh-resolution mass spectrometry (UHRMS)-based analytical methodology was developed in this work. The analytical strategies, including selection of compatible solvent for extraction, evaluation of ionization solvent for effective electrospray ionization, and multi-dimensional data analysis, were established to ensure a comprehensive characterization of complex compositions in wood extractives. Extraction capability of seven solvents with varied polarities was examined by a standard reference material of hardwood biomass and evaluated based on thousands of compounds which were much more than those discovered before. With a variety of data-processing approaches, including compound type distribution, double bond equivalent versus carbon number plot, and van Krevelen diagram, the chemodiversity of the extractives was fully explored from different perspectives. This work greatly expanded the compound library of wood extractives and could also provide guidance for the integrated composition analysis of other biomass materials.


Assuntos
Madeira , Biomassa , Espectrometria de Massas , Solventes/química , Madeira/química
4.
Molecules ; 26(23)2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34885752

RESUMO

Considering the toxicity of the impurities of synthesized anthraquinone, this study clarified new catalytic compounds for kraft cooking with improved carbohydrate yield and delignification and less mutagenicity, which are important for ensuring the safety of paper products in contact with food. The 2-methylanthraquinone contents of teak (Tectona grandis) woods were 0.18-0.21%. Acetone extracts containing 2-methylanthraquinone from Myanmar and Indonesia teak woods as additives improved lignin removal during kraft cooking of eucalyptus wood, which resulted in kappa numbers that were 2.2-6.0 points lower than the absence of additive. Myanmar extracts and 2-methylanthraquinone improved carbohydrate yield in pulps with 1.7-2.2% yield gains. Indonesia extracts contained more deoxylapachol and its isomer than 2-methylanthraquinone. The residual content of 2-methylanthraquinone in the kraft pulp was trace. Although Ames tests showed that the Indonesia and Myanmar extracts were mutagenic to Salmonella typhimurium, 2-methylanthraquinone was not. The kraft pulp obtained with the additives should be safe for food-packaging applications, and the addition of 0.03% 2-methylanthraquinone to kraft cooking saves forest resources and fossil energy in industries requiring increased pulp yield.


Assuntos
Carboidratos/biossíntese , Lamiaceae/química , Extratos Vegetais/química , Madeira/química , Acetona/química , Antraquinonas/química , Antraquinonas/toxicidade , Carboidratos/química , Catálise , Eucalyptus/química , Extratos Vegetais/farmacologia
5.
Materials (Basel) ; 14(7)2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33810257

RESUMO

Wood extractives have an influence on different material properties. This study deals with the changes in wood extractives of larch sapwood due to two different low doses of energy irradiations. Electron beam irradiation (EBI) and γ-ray irradiation treatments were done by using two industrial processes. After the different modifications the extractions were performed with an accelerated solvent extractor (ASE) using hexane and acetone/water. The qualitative and quantitative chemical differences of irradiated larch sapwood samples were analysed using gas chromatography-mass spectrometry (GC-MS) and Fourier-transform infrared spectroscopy (FT-IR) vibrational spectroscopy methods. The yields of the quantitative extractions decreased due to the two different irradiation processes. While the compounds extracted with nonpolar solvent from wood were reduced, the number of compounds with polar functionalities increased based on the oxidation process. Quantitatively, resin acids and polyphenols were highly affected when exposed to the two irradiation sources, leading to significant changes (up, down) in their relative amount. Furthermore, two new substances were found in the extracts of larch sapwood samples after EBI or γ-ray treatments. New insight into the different effects of larch sapwood and wood extractives by EBI and γ-ray was gained in this study.

6.
Food Chem ; 295: 156-164, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174744

RESUMO

During ageing, wood adsorbs volatile compounds from beverages. However, chemical interactions involved in sorption still remain unclear, as well as wood capacity to transfer such compounds to subsequent matrices when reused. Therefore, extractions were conducted from used wood manipulating variables such as ethanol concentration, contact temperature and pH, in order to determine their effect in the interaction and consequent recovery of wine volatiles from wood. Mathematical models were outlined, which demonstrated an exclusive effect of ethanol concentration on the extraction of wine volatiles adsorbed in wood, more prominent for compounds of higher hydrophobicity. Thus adsorption of wine volatiles was shown to be based on hydrophobic interactions. Recovery of wood extractives was also modeled, confirming the known positive effect of ethanol and temperature on the overall extraction of characteristic wood compounds. When reused, wood transferred wine compounds to hydroalcoholic matrices, demonstrating its impact and potential as a vector for aroma transference.


Assuntos
Quercus/química , Compostos Orgânicos Voláteis/química , Vinho/análise , Madeira/química , Adsorção , Etanol/química , Concentração de Íons de Hidrogênio , Temperatura , Fatores de Tempo
7.
Environ Toxicol Chem ; 38(5): 936-946, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30702183

RESUMO

Sediment from a log pond located in south Finland contained 15 000 to 50 000 mg/kg dry weight of C10 -C40 hydrocarbons. It was unclear whether they originated from the hydraulic fluid of the log hoist or the wood extractives. In the present study, methods of effect-directed analysis were used for the identification of toxicants. A combination of fractionation, biotesting, and chemical analyses revealed that the key toxicant of log pond sediment was retene, a dialkyl-substituted phenanthrene derived from wood resin acids. In addition, the most toxic fraction included 3 other wood-originated diterpenic compounds. Typical wood extractives such as sesquiterpenes and odd-carbon number alkanes in the range C21 -C33 were identified in the fraction, which showed minor genotoxic potency. The most polar fraction contained triterpenes and showed estrogenic activity. No evidence for the presence of hydraulic fluid in sediment was found. The study also indicated that in cases where the organic matter content of sediment or soil is high, using the results of standard mineral oil analysis in risk management can lead to incorrect actions because standard methods do not differentiate petroleum hydrocarbons from biogenic hydrocarbons. Environ Toxicol Chem 2019;9999:1-11. © 2019 SETAC.


Assuntos
Poluentes Ambientais/toxicidade , Sedimentos Geológicos/química , Hidrocarbonetos/toxicidade , Indústrias , Compostos Orgânicos/toxicidade , Petróleo/toxicidade , Madeira/química , Aliivibrio/efeitos dos fármacos , Cromatografia Gasosa , Finlândia , Luminescência , Fenantrenos/toxicidade
8.
Int J Biol Macromol ; 119: 582-587, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30071222

RESUMO

In this study, diethyl ether extractives were isolated from Phoebe zhennan wood and then added into PLA matrix for the preparation of UV protective films (UV-PF). The results revealed that the diethyl ether extractives had good compatibility with PLA. The prepared UV-PF with the addition of 24 wt% extractives showed complete absorption of UV-C (200-280 nm) and UV-B (280-315 nm) and more than 90% absorption of UV-A (315-400 nm), indicating the addition of extractives into PLA contributed to the super UV resistant ability of the PLA based films. The UV-PF still exhibited excellent UV absorbability after strong UV light irradiation. The differential Scanning Calorimetry (DSC) analysis of the films showed that the UV-PF had relatively low thermal degradation temperature compared to the neat PLA films (PF), while the UV-PF showed stronger tensile strength with comparison to that of the PF. The results on the chemical composition analysis of the diethyl ether extractives revealed that the UV absorbability of the UV-PF may own to the benzene structure, CO bonds, CC bonds in the constituents of the extractives, which all have strong absorption in the near UV-region (200-400 nm).


Assuntos
Lauraceae/química , Extratos Vegetais/química , Poliésteres/química , Protetores contra Radiação/química , Protetores contra Radiação/farmacologia , Raios Ultravioleta/efeitos adversos , Estabilidade de Medicamentos , Embalagem de Alimentos , Temperatura , Resistência à Tração
9.
Saudi J Biol Sci ; 24(2): 399-404, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28149179

RESUMO

As one of the dominant plantations in north and central China, poplar was considered as the uppermost wood raw materials, however, the chemical constituents of poplar wood weren't effectively used by high added value. Therefore, the molecules of wood extractives in Populus lasiocarpa and Populus tomentosa were extracted and studied to further utilize the bio-resources. The results showed that the LD-010, LD-021, LD-150, LD-174 wood extractives were identified as having 3, 24, 3 27 components, respectively. P. lasiocarpa wood was fit to extract 2,4-hexadiyne, 1,3,3-trimethyl-2-hydroxymethyl-3,3-dimethyl-4-(3-methylbut-2-enyl)-cyclohexene, and P. tomentosa wood was fit to extract 1,5-hexadien-3-yne, (all-E)-2,6,10,15,19,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene. So the extractives of poplar wood contained rich and rare drug and biomedical activities.

10.
Appl Microbiol Biotechnol ; 100(4): 1589-1596, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26685670

RESUMO

Wood contains primary extractives, which are present in all woods, and secondary extractives, which are confined in certain wood species. Extractives in wood play a major role in wood-bonding processes, as they can contribute to or determine the bonding relevant properties of wood such as acidity and wettability. Therefore, extractives play an immanent role in bonding of wood chips and wood fibres with common synthetic adhesives such as urea-formaldehyde-resins (UF-resins) and phenol-formaldehyde-resins (PF-resins). Extractives of high acidity accelerate the curing of acid curing UF-resins and decelerate bonding with alkaline hardening PF-resins. Water-soluble extractives like free sugars are detrimental for bonding of wood with cement. Polyphenolic extractives (tannins) can be used as a binder in the wood-based industry. Additionally, extractives in wood can react with formaldehyde and reduce the formaldehyde emission of wood-based panels. Moreover, some wood extractives are volatile organic compounds (VOC) and insofar also relevant to the emission of VOC from wood and wood-based panels.


Assuntos
Adesivos/metabolismo , Misturas Complexas/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Madeira/química
11.
Bioresour Technol ; 146: 294-300, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23948266

RESUMO

In order to remove wood extractive compounds from pulp mill sludge and thereby enhancing anaerobic digestibility, samples were subjected to either oxidative hydrothermal treatment (wet oxidation) or non-oxidative hydrothermal treatment (thermal hydrolysis). Treatments were carried out at 220 °C with initial pressure of 20 bar. More than 90% destruction of extractive compounds was observed after 20 min of wet oxidation. Wet oxidation eliminated 95.7% of phenolics, 98.6% fatty acids, 99.8% resin acids and 100% of phytosterols in 120 min. Acetic acid concentration increased by approximately 2 g/l after 120 min of wet oxidation. This has potential for rendering sludge more amenable to anaerobic digestion. In contrast thermal hydrolysis was found to be ineffective in degrading extractive compounds. Wet oxidation is considered to be an effective process for removal of recalcitrant and inhibitive compounds through hydrothermal pre-treatment of pulp mill sludge.


Assuntos
Resíduos Industriais , Esgotos , Eliminação de Resíduos Líquidos/métodos , Madeira/química , Ácido Acético/química , Biodegradação Ambiental , Carbono/química , Desenho de Equipamento , Ácidos Graxos/química , Concentração de Íons de Hidrogênio , Hidrólise , Oxirredução , Oxigênio/química , Papel , Fitosteróis/química , Pinus , Pressão , Temperatura , Fatores de Tempo
12.
Acta amaz ; 37(2): 213-218, jun. 2007. ilus, tab
Artigo em Português | LILACS | ID: lil-462049

RESUMO

No ramo da preservação de madeira, a eficiência de compostos naturais há muito tem sido avaliada, visando encontrar substâncias que não só aumentem a vida útil de madeiras de baixa durabilidade, mas também causem menor dano ao meio ambiente. Nesse contexto, o potencial de extrativos do lenho e da casca das espécies madeireiras Pouteria guianensis,Buchenavia parviflora e Dinizia excelsa em repelir o ataque de cupins Nasutitermes sp. foi avaliado, utilizando-se como substrato a espécie Simarouba amara, de baixa durabilidade. Os extrativos foram obtidos em etanol 95 por cento, diluídos em solução hidroalcoólica (1 e 0,1 por cento), e impregnados em blocos de S. amara, segundo ASTM D1413-76. Os blocos foram montados em quadrado latino em uma plataforma e submetidos ao ataque dos cupins. O efeito das soluções foi classificado pela perda de peso dos blocos de S. amara. Os resultados mostraram que a maioria dos tratamentos conferiu ótima resistência à madeira de S. amara. O melhor tratamento foi aquele efetuado com extrativos da casca de P. guianensis, onde a perda foi somente de 10 por cento do peso inicial dos blocos, enquanto que o menos efetivo foi aquele com extrativos da casca de D. excelsa, com perda de 70 por cento de peso do bloco. Assim, pode-se concluir que os extrativos do lenho e da casca de P. guianensis e B. parviflora e do lenho de D. excelsa apresentam, a princípio, compostos com propriedades de repelência a Nasutitermes sp., e os extrativos da casca de D. excelsa não apresentam estes componentes.


In wood preservation, efficiency evaluation of some natural compounds has been going on for some time, looking for substances that can be used to increase the useful life of wood species, and that are less damaging to the environment. In this context, we evaluted the potential of wood and bark extractives of the species Pouteria guianensis,Buchenavia parviflora and Dinizia excelsa in repelling Nasutitermes sp. As substrate, blocks of Simarouba amara species, of low durability, was used. The extractives were obtained in ethanol 95 percent, diluted in hydro-alcoholic solution (1 percent and 0.1 percent), and impregnated in a block of S. amara, according to ASTM D1413-76. The blocks were arranged on a platform in Latin square and submitted to termite attack. The effect of the solutions on termites was classified according to weight loss of the S. amara blocks. The results showed that a big majority of extractive treatments provided high resistance to S. amara wood. The best treatment was that made with the P. guianensis bark extractives, where loss was only 10 percent of the initial block weight. The less effective treatment was that of the D. excelsa bark extractives, with 70 percent loss of block weight. Thus, we concluded that the wood and bark extractives of P. guianensis and B. parviflora and wood extractives of D. excelsa present chemical compounds with repellent properties against Nasutitermes sp., while the bark extractives of D. excelsa do not.


Assuntos
Madeira , Ecossistema Amazônico , Inseticidas
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