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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2005.11.012 Byline: Patrik Eklund (a), Agnieszka Rusinowska (b)(c), Harrie De Swart (d) Keywords: Constraints satisfaction; Consensus; Committees Abstract: In this paper, we apply a consensus model to decision-making in committees that have to choose one or more alternatives from a set of alternatives. The model does not use a voting rule nor a set of winning coalitions. Every decision maker evaluates each alternative with respect to given criteria. The criteria may be of unequal importance to a decision maker. Decision makers may be advised by a chairman to adjust their preferences, i.e., to change their evaluation of some alternative(s) or/and the importance of the criteria, in order to obtain a better consensus. The consensus result should satisfy constraints concerning the consensus degree and the majority degree. A simple example is presented. Author Affiliation: (a) UmeA[yen] University, Department of Computing Science, SE-90187 UmeA[yen], Sweden (b) Radboud University, Faculty of Management Science, P.O. Box 9108, 6500 HK Nijmegen, The Netherlands (c) Warsaw School of Economics, Department of Mathematical Economics, Al. Niepodleglosci 162, 02-554 Warsaw, Poland (d) Tilburg University, Faculty of Philosophy, P.O. Box 90153, 5000 LE Tilburg, The Netherlands Article History: Received 29 September 2004; Accepted 23 November 2005 Article Note: (footnote) [star] The authors wish to thank Professor Hannu Nurmi for very useful discussions concerning consensus theory. They are also grateful to two anonymous referees for their suggestions.

The low-molar-mass (LMM) fraction, only, i.e., the GC-eluting compounds, which are mainly lignans, has been characterized in Norway spruce knotwood hydrophilic extracts previously. Of this fraction, many lignans and sesquilignans and all GC peaks supposedly representing dilignans remain unidentified. In this work, dilignans and the GC non-eluting compounds (the high-molar mass fractions, HMM) were characterized in a 7-hydroxymatairesinol-reduced knotwood ethanol extract of Norway spruce by using several fractionation and analytical techniques. A methyl tert -butyl ether (MTBE) insoluble fraction of the extract contained mainly HMM material, of which the main part was shown to consist of lignan oligomers. The oligolignans (with a molar mass up to approximately 3700 Da) seemed to be linked by 5 5′ bonds, some of them containing one or two guaiacylglycerol ether units linked to the lignan by β O 4 or β 5 bonds. Several oligolignans were identified or tentatively identified. The MTBE soluble fraction, which accounted for the major part (81%) of the extract, contained mainly LMM material (lignans, sesqui- and dilignans). The part of the HMM material in the MTBE soluble fraction that was easily isolable (2%) seemed to contain polymers of fatty acids and alcohols, resin acids, and sterols. [ABSTRACT FROM AUTHOR]

The structures of the naturally occurring lignan hydroxymatairesinol (HMR) and TADDOL-like α -conidendrin-based chiral 1,4-diols (LIGNOLs) have been studied at DFT/B3LYP/TZVP level of theory, for the first time applying the density functional dispersion correction (DFT-D3) [1] and employing the BJ-damping (-D3(BJ)) [2] . This study establishes the necessity of treating the dispersion interactions properly in DFT optimizations. Several of the conformers received were not found in previous studies and the 4Ph4 structure received applying D3 is now published for the first time as a quantum chemically optimized structure. [ABSTRACT FROM AUTHOR]

Abstract: In seed extracts of five oilseed species, in bran extracts of three cereal species, and in seed and/or whole berry extracts of 10 berry species, the concentrations of a large number of lignans and the enantiomeric composition of selected lignans were determined. In the case of sesame and hemp seeds, the lignan content and composition of the whole seeds was compared to that of the hulled seeds. The results showed that cloudberry seeds are the third most lignan-rich food source after linseeds and whole sesame seeds, and that most of the berry species analysed were more lignan-rich than the cereal brans. The lignans are concentrated in the hull of the oilseeds and in the seeds of the berries. In most samples, secoisolarici-, pino-, medio-, and syringaresinol were present as a mixture of two enantiomers. [Copyright &y& Elsevier]

Abstract: Norway spruce O-acetyl-galactoglucomannans (GGM) are water-soluble hemicelluloses that have potential to be produced in large scale as a side product of the mechanical pulping industry or by hot-water extraction of wood. Chemical modification is often needed to tailor such water-soluble polysaccharides into industrially valuable compounds. In this work, treatment of GGM with butyric and benzoic anhydride in pyridine/dimethylformamide rendered GGM derivatives, which were hydrophobic and partially soluble in organic solvents. The degree of substitution can be adjusted by varying the quantity of the reagent and reaction temperature. The dn/dc value for the benzoyl ester of GGM was determined in 0.05M LiBr DMSO in order to obtain accurate molar mass analysis with SEC-MALLS-RI. Novel substances with adjusted hydrophobicity can thus be prepared on one step synthesis from natural hemicelluloses, which then showed a slight increase in the molar mass upon esterification. [Copyright &y& Elsevier]

Abstract: A convenient semi-synthesis of (8R,8′R)-matairesinol 4,4′-di-O-β-d-glucopyranoside (MDG), found in the stems of Trachelospermum asiaticum var. intermedium, is described starting from the readily available starting materials d-glucose and hydroxymatairesinol. By this approach the synthesis of MDG can be accomplished in six steps with an overall yield of 28%. In addition, the first complete NMR-spectroscopic characterization of MDG was accomplished by the combination of standard NMR techniques and spectral simulations performed with the PERCH NMR simulation software. [ABSTRACT FROM AUTHOR]

Abstract: Screening of 400 Streptomyces strains for biotransformation of the natural lignan matairesinol led to the identification of Streptomyces sp. LS136, capable of producing a single metabolite in moderate yields. Isolation and purification by preparative HPLC, followed by structural analyses by LC-MS and NMR, established the structure as matairesinol-4-O-rhamnoside. This bacterial strain was also used for rhamnosylation of the abundant natural lignans, hydroxymatairesinol and secoisolariciresinol. [Copyright &y& Elsevier]

The oxidative transformation of the two isomers of the natural lignan hydroxymatairesinol from Norway Spruce (Picea abies) by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), has been studied. Significant differences in the outcome of the reactions were observed when the pure isomers of hydroxymatairesinol were reacted with DDQ under the same conditions. The different stereoelectronic effects in the two isomers as well as their conformational structures seem to determine the site of reaction, which results in different reaction products. Several products were identified by GC–MS and NMR spectroscopy. Oxomatairesinol was obtained in a yield of 25%. [Copyright &y& Elsevier]

Highlights: [•] The covalent bonding of Cat-GGM was demonstrated with MALDI-TOF-MS. [•] Polyelectrolyte titration is a rapid method to measure the DS. [•] The DS of cationic GGM can be tailored. [•] Cationised GGM was acetylated, which made the product hydrophobic. [•] Cat-GGM can potentially be utilised as polyelectrolyte layers in packaging [ABSTRACT FROM AUTHOR]

Abstract: Phytoestrogens are plant-derived food ingredients assumed to contribute to the prevention of hormone-dependent cancers, osteoporosis, cardiovascular disease, and menopausal symptoms. Lignans occur in numerous food plants and various structures; they are common constituents of human diet, and estrogen activity has been assessed for lignan metabolites formed in the mammalian intestine. We examined natural lignans and semisynthetic norlignans for estrogen and antiestrogen activity. A transformed yeast strain (Saccharomyces cerevisiae) expressing the estrogen receptor alpha and a reporter system was applied as test system. Some plant lignans showed estrogen activity while others and the semisynthetic norlignans were moderately active antiestrogens. Docking of lignans to protein models of estrogen receptor alpha in the active and inactive form sustained the results of the yeast estrogen assay and supported the concept of plant lignans as phytoestrogens. [Copyright &y& Elsevier]

Abstract: Acetylated galactoglucomannans (GGMs) are the main hemicellulose type in most softwood species and can be utilized as, for example, bioactive polymers, hydrocolloids, papermaking chemicals, or coating polymers. Acetylation of spruce GGM using acetic anhydride with pyridine as catalyst under different conditions was conducted to obtain different degrees of acetylation on a laboratory scale, whereas, as a classic method, it can be potentially transferred to the industrial scale. The effects of the amount of catalyst and acetic anhydride, reaction time, temperature and pretreatment by acetic acid were investigated. A fully acetylated product was obtained by refluxing GGM for two hours. The structures of the acetylated GGMs were determined by SEC-MALLS/RI, 1H and 13C NMR and FTIR spectroscopy. NMR studies also indicated migration of acetyl groups from O-2 or O-3 to O-6 after a heating treatment in a water bath. The thermal stability of the products was investigated by DSC-TGA. [Copyright &y& Elsevier]

Abstract: Recently it was found that cell cultures and plants of Linum species contain lignans of various chemical structures. The stereochemistry of these compounds differ among species. Cell cultures of L. album accumulate (−)-podophyllotoxin together with pure (−)-secoisolariciresinol. The presence of both enantiomers of the precursor pinoresinol indicates that in L. album cell cultures the reactions from pinoresinol to secoisolariciresinol are the first steps determining enantiospecificity in biosynthesis of podophyllotoxin. Seeds of L. usitatissimum contain almost enantiomerically pure (+)-secoisolariciresinoldiglucosid derived from (+)-secoisolariciresinol. A cell culture of this species contains a mixture of both enantiomers of pinoresinol and pure (+)-secoisolariciresinol. In order to get more insight into the mechanism of (−)- and (+)-secoisolariciresinol biosynthesis, respectively, we isolated a cDNA encoding pinoresinol–lariciresinol reductase (PLR) from L. album. The heterologously expressed PLR-La1 converts only (+)-pinoresinol into (−)-secoisolariciresinol. In contrast, the heterologously expressed PLR from L. usitatissimum converts only (−)-pinoresinol to (+)-secoisolariciresinol confirming the results from others. Comparison of all available PLR protein sequences resulted in a few amino acids which may be responsible for the action of the PLRs with respect to the different enantioselectivity. A mutagenesis approach could not confirm this hypothesis. Aspects about the evolution of PLRs are discussed. [Copyright &y& Elsevier]

• Phythochemical phenols of the lignan and stilbene families showed good stability at elevated temperatures. • Lignans and stilbenes retained their antioxidative properties even at temperatures up to 200 °C. • The studied phenols showed to protect the PUFA linoleic acid against high temperature degradation and significantly decreased the degradation rate. Thermal transformations of polyphenols from the lignan and stilbene families were investigated at temperatures ranging from 200 °C to 250 °C, in polyethylene glycol (PEG-400), dimethylformamide (DMF) and in sunflower oil (SO). The polyphenols showed varying degrees of thermal stabilities and in some cases intramolecular transformations were observed. The formed products were isolated and characterized. Oligomerization of the polyphenols at thermo-oxidative conditions was also investigated. Finally, the antioxidative activity of the polyphenols against thermo-oxidative degradation α -linoleic acid was investigated at 200 °C. The results suggested that the studied substrates retained their antioxidative properties at elevated temperatures, with stilbenes showing most efficient protection against thermo-oxidative degradation of polyunsaturated fatty acids. [ABSTRACT FROM AUTHOR]

The influence of oxygen (0–50 bar) on the molar mass and composition of hemicelluloses after hydrothermal treatment of spruce chips was studied in a batch reactor setup at 130 °C–160 °C. Purified galactoglucomannan was studied as a reference. The dissolved oxygen enhanced significantly the depolymerization of hemicelluloses from over 15,000 g/mol to 180 g/mol (monomers) as well as promoted acids formation from the monosaccharides. About 2–3 times faster depolymerization was observed already with rather low amounts of oxygen (2–8 bar), while the kinetics of depolymerization was significantly slower in inert atmosphere. The decrease in pH from neutral to as low as 2.5 lead to an autocatalytic effect on the polysaccharide hydrolysis and the consecutive reactions of monosaccharides. The results emphasize the importance of performing hydrothermal treatment under inert atmosphere if large polymeric hemicellulsoses are desired or if monosaccharides are targeted in hydrolysis of hemicelluloses. If autocatalysis begins, it is difficult to stop. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Galactose units of spruce galactoglucomannan (GGM), guar galactomannan (GM), and tamarind (galacto)xyloglucan (XG) were selectively allylated. Firstly aldehyde functionalities were formed at the C-6 position via enzymatic oxidation by galactose oxidase. The formed aldehydes were further derivatized by an indium mediated Barbier–Grignard type reaction, resulting in the formation of homoallylic alcohols. In addition to allylic halides, the same reaction procedure was also applicable for GGM, when using propargyl bromide as halide. All reaction steps were done in water, thus the polysaccharides were modified in a one-pot reaction. The formation of the allylated, or propargylated, product was identified by MALDI-TOF–MS. All polysaccharide products were isolated and further characterized by GC–MS or NMR spectroscopy. By this chemo-enzymatic process, we have demonstrated a novel method for derivatization of GGM and other galactose-containing polysaccharides. The derivatized polysaccharides are potential platforms for further functionalizations. [Copyright &y& Elsevier]

Abstract: Prostate cancer cells frequently develop resistance toward androgen-deprivation and chemotherapy. To identify new approaches to treat androgen-dependent prostate cancer, we have performed a structure–activity analysis of lignan polyphenols for cancer cell specific sensitization to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a death ligand that has ability to induce tumor-specific cell death. In this study, we report that the lignan nortrachelogenin (NTG) is the most efficient of the 27 tested lignan compounds in sensitizing prostate cancer cells to TRAIL-induced apoptosis. Importantly, pretreatment with NTG does not sensitize a non-malignant prostate cell line to TRAIL-induced cell death. The structural comparison of lignans reveals that the dibenzylbutyrolactone skeleton is required for the apoptosis-sensitizing activity, while substitutions at the aromatic rings do not seem to play a critical role in this lignan function. Our study also characterizes the cellular effects and molecular mechanisms involved in NTG anticancer activity. We previously reported that specific lignans inhibit the Akt survival-signaling pathway in concert with TRAIL sensitization. While NTG is also shown to be a effective inhibitor of Akt signaling, in this study we further demonstrate that NTG potently inhibits tyrosine kinase (RTK) activation in response to growth factors, such as insulin and insulin-like growth factor I (IGF-I). Our results identify NTG as a novel agent for prostate cancer therapy with ability to inhibit Akt membrane localization and activity as well as the activation of growth factor receptors (GFRs), thereby efficiently synergizing with TRAIL exposure. [Copyright &y& Elsevier]

Abstract: The antimicrobial effects of the wood-associated polyphenolic compounds pinosylvin, pinosylvin monomethyl ether, astringin, piceatannol, isorhapontin, isorhapontigenin, cycloXMe, dHIMP, ArX, and ArXOH were assessed against both Gram-negative (Salmonella) and Gram-positive bacteria (Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus aureus) and yeasts (Candida tropicalis, Saccharomyces cerevisiae). Particularly the stilbenes pinosylvin, its monomethyl ether and piceatannol demonstrated a clear antimicrobial activity, which in the case of pinosylvin was present also in food matrices like sauerkraut, gravlax and berry jam, but not in milk. The destabilization of the outer membrane of Gram-negative microorganisms, as well as interactions with the cell membrane, as indicated by the NPN uptake and LIVE/DEAD viability staining experiments, can be one of the specific mechanisms behind the antibacterial action. L. monocytogenes was particularly sensitive to pinosylvin, and this effect was also seen in L. monocytogenes internalized in intestinal Caco2 cells at non-cytotoxic pinosylvin concentrations. In general, the antimicrobial effects of pinosylvin were even more prominent than those of a related stilbene, resveratrol, well known for its various bioactivities. According to our results, pinosylvin could have potential as a natural disinfectant or biocide in some targeted applications. [Copyright &y& Elsevier]

Abstract: The readily available natural lignan hydroxymatairesinol was transformed into sterically hindered and optically pure diphenyl, di-2-naphthyl, and tetramethyl 1,4-diol derivatives via arylation/alkylation of the aryltetralinbutyrolactone lignan (−)-conidendrin. In addition, the diastereoselective formation of stable hemiketals from the highly substituted butyrolactone was studied in detail. The conformations of the molecules prepared were studied computationally at molecular mechanics (MM), Hartree–Fock (HF)/6-31G∗, and (DFT/B3LYP/TZVP) levels including entropy contributions and by NMR-spectroscopy. The conformations adopted showed that these novel chiral 1,4-diols may be suitable as chiral ligands for the development of new chiral transition metal and organo catalysts. [Copyright &y& Elsevier]

Abstract: The C-6 unit of methyl α-d-galactopyranoside was selectively modified by combining enzymatic oxidation with an indium-mediated allylation reaction. The Barbier–Grignard type reaction, where a carbonyl group reacts with an allyl halide, proceeds in aqueous solution, even with water as the only solvent; thus carbohydrates can be modified without the need for drying or protection–deprotection steps. The corresponding homoallyl alcohols are produced in high yields of >90% in the reactions with allyl bromide and cinnamyl chloride. The main products were isolated and characterized by GC–MS and NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: Highly oxidized lignans produced during the cytochrome P-450 metabolism in the cells show biological activities significantly different from those of their parent natural compounds. Lignans precursors of mammalian enterolignans were treated with a methyltrioxorhenium/hydrogen peroxide catalytic system to afford new compounds oxidized at benzylic as well as in arylic positions. The evaluation of the antioxidant and apoptogenic activity by in vivo protocols of these compounds showed some interesting structure–activity relationships related to the oxidation degree of the molecules. [Copyright &y& Elsevier]

Abstract: The lignans matairesinol (MAT) and secoisolariciresinol (SECO) were fed to Min mice at 0.02% (w/w) in diet to study their effects on intestinal tumor development. The mean number (67 vs. 51, P=0.052) and size (1.4 vs. 1.2mm, P=0.011) of tumors in the MAT group was elevated when compared with the control group. Tumor formation of the SECO group did not differ from the control group. Intake of MAT increased the level of both MAT and enterolactone in the plasma while SECO feeding increased SECO, enterodiol, and enterolactone (P=0.001). These results showed that MAT or SECO do not prevent intestinal carcinogenesis in Min mice and that MAT may have adverse effects. [Copyright &y& Elsevier]

In this work, ozone has been used to study the transformation of the antibiotic sulfadiazine (SDZ). SDZ and its transformation products was investigated using liquid chromatography coupled to mass spectrometry and using NMR. The results revealed that 6% of SDZ is transformed into 2-aminopyrimidine. A significant amount of SDZ undergoes a rearrangement reaction followed by ring-closing reactions. One of these products, SDZ-P15, is the main product after 240 min of ozonation. Almost 30% of SDZ transforms into SDZ-P15. SDZ was also transformed via the addition of one or more hydroxyl groups, via the oxidation of an amine group to a nitro group as well as via a bond cleavage reaction. Most of the intermediate products presented in this study have not previously been reported as SDZ transformation products formed using ozonation technology. Image 1 • The antibiotic sulfadiazine (SDZ) can be removed by ozonation. • The main transformation products were identified and quantified. • The removal of SDZ and its transformation products was compared for catalytic and non-catalytic ozonation. • A novel SDZ transformation pathway was investigated. [ABSTRACT FROM AUTHOR]

• UVA-irradiation increased the antioxidant activity of stilbene-rich bark extracts. • UVA-irradiation decreased the capacity of extracts to prevent lipid oxidation. • UVA-irradiation resulted in slightly increased or maintained antimicrobial activity. • Both untreated and modified extracts may have commercial potential as preservatives. Bark of Norway spruce (Picea abies [L.] Karst.) trees contains large amounts of polyphenolic stilbene glucosides. Stilbene-rich bark extracts could be utilized as e.g., preservatives due to their antioxidative, antifungal, and antibacterial properties. As stilbenes are photosensitive compounds, ultraviolet (UV) light induces a well-known intramolecular cyclization, leading to the formation of substituted phenanthrenes via a dihydro-phenanthrene intermediate. The possible UV-induced changes in the biological activities of the stilbene extracts remain, however, poorly known. Such information is crucial for practical application development. This study elucidated for the first time, how UVA-treatments of spruce bark extracts affect the chemical composition of the extracts, and further change their antimicrobial and antioxidative activities. Norway spruce inner bark was extracted (' Extract ') and soluble mono- and disaccharides removed using Amberlite XADHP7 (' Extract XAD'). These extracts were then treated with UVA-light (' Extract UV ', ' Extract XAD UV '), and chemical properties analyzed by GC–MS and HP-SEC. The antimicrobial activities of untreated and modified extracts against Staphylococcus aureus , Candida albicans, and Escherichia coli, were evaluated. Additionally, differences in the antioxidant activity between the untreated and UV-treated bark extracts were measured at a total stilbene concentration of 0.5 mg/mL EtOH, using the FRAP and ORAC methods. Also, antioxidant effects were evaluated in a liposome model to assess the ability of the extract to prevent lipid oxidation. Our novel results show that UVA-induced modification of the stilbene-rich inner bark extracts increased the radical scavenging activity. However, UVA-irradiation decreased the capacity of the extracts to prevent lipid oxidation in the liposome system method. The results also indicate a maintained or slightly increased antimicrobial activity after UVA-modification. This study shows that Norway spruce bark stilbenoids and the compounds formed by UVA-irradiation thereof show biological activity, and thus have commercial potential as e.g., preservatives. [ABSTRACT FROM AUTHOR]