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Technical hydrolysis lignin (THL) was micronized by grinding in a rotary-jet mill to obtain a fraction of approximately 5 mm. Both initial and milled THLs were liquefied by thermal alkaline treatment at 220°C for 2 h. Upgraded THLs that were nonmilled (L1) and milled (L2) were desalted by treatment with cation-exchanged resin and were dried. Micronization affected the course of hydrothermal alkaline treatment and the structure and composition of the obtained lignin. Thus, L2 contained much less concomitant polysaccharides and extractives than L1 and was more condensed. The molecular weights of L1 and L2 were 1100 and 1000 Da, respectively, as determined by size-exclusion chromatography. Structural characterization carried out by employing tandem electrospray ionization-mass spectrometry and 1D and 2D nuclear magnetic resonance spectroscopy revealed that small amounts of β-O-4 (∼6 mol.%), β-5, and β-β structures still remained in L1 and L2. Overall, upgraded lignins are oligomers (trimers-pentamers) with highly degraded propane chains and possess polyconjugated condensed aromatic structures. Upgraded THL seems to be a promising raw material for polymeric formulations.

Arabinose from arabinogalactan side chains was hypothesized as a possible binding site for chlorogenic acids in coffee melanoidins. To investigate this hypothesis, a mixture of 5-O-caffeoylquinic acid (5-CQA), the most abundant chlorogenic acid in green coffee beans, and (alpha 1 -> 5)-L-arabinotriose, structurally related to arabinogalactan side chains, was submitted to dry thermal treatments. The compounds formed during thermal processing were identified by electrospray ionization mass spectrometry (ESI-MS) and characterized by tandem MS (ESI-MSn). Compounds composed by one or two CQAs covalently linked with pentose (Pent) residues (1-12) were identified, along with compounds bearing a sugar moiety but composed exclusively by the quinic or caffeic acid moiety of CQAs. The presence of isomers was demonstrated by liquid chromatography online coupled to ESI-MS and ESI-MSn. Pent(1-2)CQA were identified in coffee samples. These results give evidence for a diversity of chlorogenic acid arabinose hybrids formed during roasting, opening new perspectives for their identification in melanoidin structures. (C) 2015 Elsevier Ltd. All rights reserved.

The phenolic composition of Cynara cardunculus L. var. altilis (DC) from south of Portugal was determined by analyzing the methanol/water/acetic acid (49.5:49.5:1) extracts of the different morphological parts of the plant, through high temperature-ultra high pressure liquid chromatography tandem mass spectrometry. From the twenty-eight phenolic compounds identified, eriodictyol hexoside was described for the first time in C. cardunculus L., and 1,4-di-O-caffeoylquinic acid, naringenin 7-O-glucoside, naringenin rutinoside, naringenin, luteolin acetyl-hexoside and apigenin acetyl-hexoside as cardoon components. Stalks outer part and capitula florets showed the highest hydroxycinnamic acids and flavonoids contents, respectively. Capitula receptacle and bracts, and stalks inner part also presented considerably high hydroxycinnamic acids contents, while leaves were rich in flavonoids. Finally, stalks outer part and capitula receptacle and bracts extracts showed the highest antioxidant activity which was in perfect tune with the phenolic compounds, particularly to hydroxycinnamic acids. These results clearly demonstrate the potential of this crop as a source of antioxidant phenolic compounds. (C) 2014 Elsevier B.V. All rights reserved.

The chemical composition of the lipophilic extract of ripe pulp of banana fruit from several banana cultivars belonging to the Musa acuminata and Musa balbisiana species (namely 'Chinese Cavendish', 'Giant Cavendish', 'Dwarf Red', 'Grand Nain', 'Eilon', 'Gruesa', 'Silver', 'Ricasa', 'Williams' and 'Zelig') was studied by gas chromatography-mass spectrometry for the first time. The banana cultivars showed similar amounts of lipophilic extractives (ca. 0.4% of dry material weight) as well as qualitative chemical compositions. The major groups of compounds identified in these fractions were fatty acids and sterols making up 68.6-84.3% and 11.1-28.0%, respectively, of the total amount of lipophilic components. Smaller amounts of long chain aliphatic alcohols and a-tocopherol were also identified. These results are a relevant contribution for the valorisation of these banana cultivars as sources of valuable phytochemicals (omega- and omega-6 fatty acids, and sterols) with well-established beneficial nutritional and health effects. (C) 2014 Elsevier Ltd. All rights reserved.

Ultra-high performance liquid chromatography (UHPLC) was applied for the first time in the analysis of wood extracts. The potential of this technique coupled to ion trap mass spectrometry in the rapid and effective detection and identification of bioactive components in complex vegetal samples was demonstrated. Several dozens of compounds were detected in less than 30 min of analysis time, corresponding to more than 3-fold reduction in time, when compared to conventional HPLC analysis of similar extracts. The phenolic chemical composition of Eucalyptus grandis, Eucalyptus urograndis (E. grandis x E. urophylla) and Eucalyptus maidenii wood extracts was assessed for the first time, with the identification of 51 phenolic compounds in the three wood extracts. Twenty of these compounds are reported for the first time as Eucalyptus genus components. Ellagic acid and ellagic acid-pentoside are the major components in all extracts, followed by gallic and quinic acids in E. grandis and E. urograndis and ellagic acid-pentoside isomer, isorhamnetin-hexoside and gallic acid in E. maidenii. The antioxidant scavenging activity of the extracts was evaluated, with E. grandis wood extract showing the lowest IC50 value. Moreover, the antioxidant activity of these extracts was higher than that of the commercial antioxidant BHT and of those of the corresponding bark extracts. These results, together with the phenolic content values, open good perspectives for the exploitation of these renewable resources as a source of valuable phenolic compounds. (c) 2013 Elsevier B.V. All rights reserved.

Linoleic acid (LA) was converted into hydroperoxides by a cloned lipoxygenase from bacterium Pseudomonas aeruginosa (PALOX) expressed in Trichoderma reesei. Its conversion was first analyzed for different LA concentrations. Then, a face-centred experimental design was used to study the effects of different variables (pH: 4.0-10.0; temperature: 5.0-45.0 degrees C; time: 2-34 h) on the conversion into hydroperoxides (13-hydroperoxy-(9Z,11E)-octadecadienoic, 9 -hydroperoxy-(10E,12Z)-octadecadienoic, 13 -hydroperoxy-(9E,11E)-octadecadienoic and 9-hydroperoxy-(10E,12E)-octadecadienoic acids) as well as on the residual LA. Fitting equations described satisfactorily the system behaviour and showed that pH and time were the most influencing variables. Finally, hydroperoxide yields above 75%, with high selectivity for the 13-hydroperoxy-(9Z,11E)-octadecadienoic acid, were obtained and results were compared with those previously obtained with Gaeumannomyces graminis tritici lipoxygenase (GGLOX). PALOX showed a maximum hydroperoxides formation at a dose 10 times lower than GGLOX. The PALOX system was more efficient than the GGLOX system although at the expense of longer reaction times and lower selectivity regarding the 13-hydroperoxy-(9Z,11E)-octadecadienoic acid. (C) 2013 Elsevier B.V. All rights reserved.

In this study, the relevance of photodegradation processes on the persistence of the fungicide thiram in waters was investigated. The photodegradation of thiram in Milli-Q water and in aqueous solutions of humic and fulvic acids, as well as the photodegradation in spiked river water were studied. Both pure thiram and one of its commercial formulations were used to prepare the solutions which were irradiated in a solar light simulator. In general, thiram photodegradation follows pseudo-first order kinetics. The half-life time of thiram 2 mg L-1 in Milli-Q water was 28 min. However, the degradation rate of thiram was significantly increased (p = 0.02) by the inert components of the thiram commercial formulation as well as by commercial humic acids and by fulvic acids isolated from river water (p < 0.004). Thus, the half-life time of thiram decreased to 24 min in the presence of the inert formulation components, while, in the presence of both humic and fulvic acids (10 mg L-1) it decreased to 22 min. Furthermore, thiram photodegradation in natural river water showed that there is a significant enhancement of the degradation rate constant of thiram relatively to Milli-Q water, corresponding to a decrease of about 38% in its half-life time. This increase of the degradation rate in river water seems to be higher than that observed in the presence of FA, suggesting that beyond organic matter, other natural river components can increase the thiram photodegradation rate. These results allow us to conclude that photodegradation by solar radiation can be an important degradation pathway of thiram in natural waters. HPLC-MS/MS allowed to identify, for the first time, three products of the photodegradation of thiram in aqueous solution. Three compounds were identified and their structure was corroborated by the MSn spectra fragmentation profile. Pathways for the formation of the products from thiram photodegradation are proposed and discussed. (C) 2013 Elsevier Ltd. All rights reserved.

Linoleic acid was converted into hydroperoxides by a Gaeumannomyces graminis tritici lipoxygenase produced recombinantly in Trichoderma reesei. Hydroperoxide production was optimized using a face-centred experimental design in order to study the effects of pH, temperature and time on the conversion of linoleic acid into four regioisomeric hydroperoxyoctadecadienoic acids (HPODE): 13-(Z,E)-, 9-(E,Z)-, 13-(E,E)-, 9-(E,E)-HPODE. Fitting equations described satisfactorily the system behavior and showed that reaction time was the most influencing independent variable. A set of independent variables (pH = 6.7, temperature = 23.9 degrees C and time = 18 h) allowed to obtain high yields of hydroperoxides (88.0%) with a good selectivity for the 13-(Z,E)-HPODE isomer (47.4%) when the initial substrate concentration was 10 g/L. The production was further investigated using industrially relevant linoleic acid concentrations (100-300 g/L) leading to HPODE yields of similar to 40% and the volumetric productivity 3.6 g/(L h), and a selectivity for 13-(Z,E)-HPODE of around 74%. (c) 2012 Elsevier B.V. All rights reserved.

The chemical composition of the lipophilic extracts of the ripe pulp of mangoes from twelve cultivars of Mangifera indica L from Madeira Island was investigated by gas chromatography-mass spectrometry (GC-MS) for the first time. The ripe pulp of these mango cultivars showed analogous amounts of lipophilic extractives, as well as similar qualitative chemical compositions. The predominant compounds were free and glycosylated sterols and fatty acids, representing 44.8-70.7% and 22.6-41.9%, respectively, of the total amount of lipophilic components. Smaller amounts of long chain aliphatic alcohols and alpha-tocopherol were also identified. These data indicate that the investigated mango cultivars are a rich source of valuable phytochemicals, contributing to the intake of at least 9.5-38.2 mg of phytosterols ( free and glycosylated) and 0.7-3.9 mg of fatty adds (omega-3 and omega-6) per 100 g of fresh mango, with recognizable beneficial effects on human nutrition and health. (C) 2013 Elsevier Ltd. All rights reserved.

Elderberry (Sambucus nigra L.) lipophilic and polar extract dietary supplementation effects were evaluated according to diabetes management indices, using an in vivo model. A research pipeline was constructed, that ranged from extract preparation, partial chemical characterization and toxicity evaluation, to examining the elderberry extract dietary supplementation effects on biofluid and tissues. Extracts toxicity was screened using an Aliivibrio fischeri bioluminescence model. A concentration of up to 60 mg/L was selected, and rat doses for oral supplementation were computed applying the interspecies correlation between A. fischeri and rats. Wistar type 2 diabetic rats, induced by streptozotocin (STZ), were fed a high-fat diet and supplemented for 4 weeks at doses of 190 and 350 mg/kg body weight/day of lipophilic and polar extract, respectively. As far as we know, lipophilic elderberry extract supplementation was assessed for the first time, while polar extract was administrated at higher doses and for a shorter period compared to previous studies, aiming to evaluate subacute supplementation effects. The polar extract modulated glucose metabolism by correcting hyperglycemia, while the lipophilic extract lowered insulin secretion. Both extracts lowered insulin resistance, without remarkable alterations to hematological indices, sera lipids and sera and tissular trace element homeostasis. In conclusion, elderberries are a potential source of bioactive compounds for formulations to be used as co-adjuvants in diabetes management.

High-performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) and tandem mass spectrometry (MS") were used to investigate the phenolic constituents in methanol, water, and methanol/water extracts of Eucalyptus globulus Labill. bark. Twenty-nine phenolic compounds were identified, 16 of them referenced for the first time as constituents of E. globulus bark, namely, quinic, dihydroxyphenylacetic, and caffeic acids, bis(hexahydroxydiphenoyl (HHDP))-glucose, galloyl-bis(HHDP)-glucose, galloyl-HHDP-glucose, isorhamentin-hexoside, quercetin-hexoside, methylellagic acid (EA) pentose conjugate, myricetin-rhamnoside, isorhamnetin-rhamnoside, mearnsetin, phloridzin, mearnsetin-hexoside, luteolin, and a proanthocyanidin B-type dimer. Digalloylglucose was identified as the major compound in the methanol and methanol/water extracts, followed by isorhamnetin-rhamnoside in the methanol extract and by catechin in the methanol/water extract, whereas in the water extract catechin and galloyl- HHDP-glucose were identified as the predominant components. The methanol/water extract was shown be the most efficient to isolate phenolic compounds identified in E. globulus bark. FP7/2007-2013 AFORE project CP-IP 228589-2 FCT - SFRH/BD/42021/2007