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Abstract: Vanillin hydrodeoxygenation was investigated using Pt/C catalyst in the temperature and total pressure ranges of 80-200 °C and 20-30 bar in several solvents, such as tetrahydrofuran, 2-propanol, water and in solventless conditions using 1:1 mass ratio of vanillin to guaiacol. The results revealed that the rate increased with increasing solvent polarity as follows: tetrahydrofuran < 2-propanol < water. The main product was p-creosol with 66% selectivity at complete vanillin conversion in HDO under 30 bar total pressure at 100 °C after 4 h using water as a solvent. In a solventless experiment with 1:1 mass ratio of vanillin-guaiacol as a feedstock only vanillin was transformed to p-creosol with 91% conversion in 4 h at 200 °C under 30 bar total pressure, while guaiacol did not produce any HDO products. Both thermodynamic analysis and kinetic modelling were performed. Vanillin hydrodeoxygenation resulted in formation of p-creosol over Pt/C catalyst using an optimum vanillin initial concentration in water solution. From the industrial point of view vanillin hydrodeoxygenation proceeded rapidly giving high yields of p-creosol in solventless hydrodeoxygenation of vanillin-guaiacol mixture, while guaiacol was not deoxygenated.Graphical Abstract: [ABSTRACT FROM AUTHOR]

A major enhancement of grease and water vapor barrier properties was accomplished with a 1-10 g/m coating of O-acetyl galactoglucomannan (GGM) ester or with GGM coatings applied as water dispersions on cartonboard. GGMs were esterified with phthalic and benzoic anhydrides, respectively. The novel phthalic esters of GGM (GGM-Ph) were characterized with HPLC, NMR, and matrix-assisted laser desorption/ionization with mass spectrometry (MALDI-TOF-MS). The degree of substitution of GGM-Ph was obtained by H NMR, C NMR, and HPLC. The GGM esters and GGM were coated onto cartonboard, and they demonstrated good moisture and very good grease resistance even with thin 1-3 g/m coatings. The time for penetration of 0.1 % rapeseed oil was 54 h with the 2.4 g/m coating thickness. The lowest water vapor transmission value was 39 g/m/24 h with 9.7 g/m coating. The GGM esters had clearly higher water resistance and slightly higher grease barrier values than native GGM. High-molar-mass-based GGM (50 kg/mol) and GGM-Ph rendered better water vapor and grease barrier properties than low-molar-mass GGM (9 kg/mol) and GGM-Ph. The GGM-based coatings can be safely used on an industrial scale as water was used as a solvent. As obtained from non-food-based side-stream wood-based resources, GGM and GGM esters project a sustainable and modern conception for barrier purposes in food packaging. [ABSTRACT FROM AUTHOR]

Pinus pinaster wood samples, obtained at different positions of three healthy trees, were subjected to two sequential extractions using an Accelerated Solvent Extraction instrument. The first extraction was carried out with hexane (to remove lipophilic extractives) and the second one with acetone/water (95:5 v/v) to recover bioactive phenolic compounds, the target compounds of this study. The extracted fractions were assayed for total yield and composition. The extracts contained a spectrum of phenolic compounds (simple phenolics, phenolic stilbenes, flavonoids and lignans) and non-phenolic components (juvabiones, resin and fatty acids, steryl esters and triglycerides). The fractionation effects achieved by consecutive extractions and the recovery of bioactive phenolics are discussed. [ABSTRACT FROM AUTHOR]

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Recent research in our group has revealed that knots, i.e. the branch bases inside tree stems, commonly contain 5–10% (w/w) of lignans. Norway spruce ( Picea abies) knots contain as much as 6–24% of lignans, with 7-hydroxymatairesinol (HMR) as the predominant (70–85%) lignan. Some other spruce species also contain HMR as the main lignan, but some spruce species have also other dominating lignans. Most fir ( Abies) species contain secoisolariciresinol and lariciresinol as the main lignans. Lignans occur also in knots of pines ( Pinus spp.), although in lower amounts than in spruces and firs. Scots pine ( Pinus silvestris) knots were found to contain 0.4–3% of lignans with nortrachelogenin as the main lignan. Lignans have been identified also in knots of some hardwoods, although flavonoids are more abundant in hardwoods. Knots are detrimental in the manufacture of pulp and paper and should preferably be removed before pulping. This is possible using a recently developed industrially applicable process called ChipSep. Recent research has also established novel synthetic routes to several lignans, such as matairesinol, secoisolariciresinol, lariciresinol and cyclolariciresinol, starting from hydroxymatairesinol by applying fairly straight-forward chemical transformations. We conclude that wood knots in certain spruce and fir species constitute the richest known source of lignans in nature. The lignans occur in knots in free form and are easily extracted by aqueous ethanol, or even by water. Not only HMR, but also other potentially valuable lignans, could be produced in a scale of hundreds of tons per year by extraction of knots separated from wood chips at pulp and paper mills. [ABSTRACT FROM AUTHOR]